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									Bulletin Board
April 22, 2011

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New statutory conditions that apply to existing and new label approvals
The Australian Pesticide and Veterinary Medicine Authority (APVMA) recently made
amendments to the Agricultural and Veterinary Chemicals Code Regulations 1995 (the
Regulations) developed by the Department of Agriculture, Fisheries and Forestry, which
now impose several new conditions on all label approvals. The new requirements came
into force on 18 March 2011 and apply to all existing approved labels, not just to those
approved after this date. These changes complement amendments made to the
Agricultural and Veterinary Chemicals Code Act 1994 in 2010 that took effect on 15 July
2010 and changed the way APVMA approves labels. Details of the requirements imposed
by these conditions have been summarised below:
When preparing labels for use in the marketplace (Marketed Product Labels - MPLs),
registrants of agvet chemical products are legally required to ensure that the label:
is attached to the container before the supply of the product (18C);
and states the relevant particulars for the label, the batch number, and (as applicable) the
manufacture date of the product and/or the expiry date (18D); and
complies with the relevant APVMA labelling code depending on whether the product is a
veterinary or agricultural chemical product (18E).
The APVMA will soon make a Labelling Standard under regulation 18A, which in
conjunction with a new Best Practice Guide will replace the existing labelling Codes
Registrants must also ensure that the label does not:
contain information contrary to that required for the label (18D(2)), and this information
must not be altered, defaced, obliterated, obscured or destroyed (18D(3)); or
contain misleading or deceptive information about a particular on the label or about the
use, safety, environmental impact, or efficacy of the chemical product (18F).
Consistent with these requirements:
information must not accompany or be placed on the container if the information negates
or varies, or qualifies or minimises the substance, purport or effect of information required
to be stated on the label (18F); and
registrants must not make any claim about registered chemical products that are
inconsistent with an instruction on the label for a container for the chemical product (18G).
The Regulations also impose record keeping obligations, including that registrants must:
retain a copy of each form of a label and record information about the use of the label,
including the batch number to which the label relates and the day the container on which
the label is attached is first released for supply (18H); and
provide the copy of a form of the label and the information about its use, as required to be
recorded by above, to the APVMA on written request. The label and information must be
provided to the APVMA within 10 days, or earlier if the APVMA believes it is necessary to
receive the label or information to prevent imminent risk to public health or occupational
health or safety (18I).
Registrants must observe all relevant conditions when preparing Marketed Product Labels
(MPLs) as the label approval is granted subject to those conditions. As the APVMA no
longer assesses or approves MPLs it is beyond its scope of operation to advise registrants
on whether their MPLs comply with the conditions of label approval in its pre-market
assessment. This is the registrant‘s responsibility. However the APVMA will check MPLs at
retail outlets and through targeted audits. Non-compliance with these statutory conditions
of approval may result in the approval being suspended or cancelled. The APVMA has
advised that all registrants refer to the Regulations, particularly Regulations 18B to 18I, to
ensure that the MPLs for which they are responsible are compliant. Full details on these
regulations can be found in 18B to 18I of the Regulations (external site).
APVMA, 5 April 2011 http://www.apvma.gov.au

Secondary Notification of Notified Chemical Glycine, N-coco acyl derivatives,
sodium salts (Sodium cocoyl glycinate) LTD/1490
Under subsection 65(1) of the Industrial Chemical (Notification and Assessment) Act 1989
(the Act), the NICNAS Director requires the secondary notification of Glycine, N-coco acyl
derivatives, sodium salts (INCI name: Sodium Cocoyl Glycinate) by Clariant (Australia) Pty
Ltd. The data required are as follows:
Any changes in the following data items from that submitted in the original notification:
Identity, Properties and Uses
a) proposed uses of the chemical;
b) concentration of the chemical in end-use products;
c) import quantity (and changes to occupational exposure for workers)
d) physico-chemical properties.
Human health:
a) the chemical‘s toxic effects following single dermal and inhalation exposure;
b) the chemical‘s toxic effects following repeated exposure;
c) the chemical‘s genotoxic effects;
d) the toxicity of the chemical to aquatic invertebrates;
e) the effects of the chemical on algae.
Any additional available data on the toxicological and/or environmental effects of the
chemical should also be provided. The requested data may be provided through the
submission of studies (tests conducted on the notified chemical or suitable analogue) or
other sources of information. The required information or alternatively, a timetable for the
provision of the requested information, should be provided to the Director within 28 days of
the publication of this notice.
NICNAS Chemical Gazette, 5 April 2011 http://www.nicnas.gov.au

Safety of food from Japan
Food Standards Australia New Zealand (FSANZ) recently assessed the situation in Japan
and has noted that the Japanese Government had moved to place new restrictions on
certain foods sourced from areas of Japan where radiation contamination has occurred. As
a precautionary measure, and consistent with approaches internationally, FSANZ have
requested on 23 March 2011 that the Australian Quarantine and Inspection Service (AQIS)
implement testing of some foods originating from four Japanese prefectures — Fukushima,
Gunma, Ibaraki and Tochigi. The foods being tested are fresh or frozen seafood, seaweed,
milk and fresh fruit and vegetables. FSANZ remains of the view that the risk of Australian
consumers being exposed to radionuclides in food imported from Japan is negligible. Milk
and fresh produce are not imported into Australia, while imports of seaweed and seafood
represent a very small proportion (5.5% and 0.46% respectively) of Australia‘s total
imports of these products. On 24 March AQIS issued a notice to industry that importers of
certain fresh or frozen foods from Japan from the four affected prefectures should be
aware that their goods will be referred for testing to check that the foods do not contain
unacceptable levels of radionuclides. Further information is available on FSANZ‘s website.
FSANZ, 6 April 2011 http://www.foodstandards.gov.au

Taiwanese standards agency finds half of children’s shoes fail phthalate standard
Taiwan‘s Bureau of Standards, Metrology and Inspection (BSMI) has published the results
of a survey of children‘s shoes available on the market, which indicated that 10 out of 21
shoes tested failed its national standard limiting the content of phthalates.
Chemical Watch, 1 April 2011 http://chemicalwatch.com/news

EPA to Open Public Comment on Proposed Standards to Protect Aquatic
Recently the U.S Environmental Protection Agency (EPA), as required by the Clean Water
Act and pursuant to a settlement agreement, is proposing for public comment standards to
protect billions of fish and other aquatic organisms each year, drawn into cooling water
systems at large power plants and factories. The proposal, based on Section 316(b) of the
Clean Water Act, would establish a common sense framework, putting a premium on
public input and flexibility. ―This proposal establishes a strong baseline level of protection
and then allows additional safeguards for aquatic life to be developed through a rigorous
site-specific analysis, an approach that ensures the most up to date technology available
is being used. It puts implementation analysis in the hands of the permit writers, where
requirements can be tailored to the particular facility,‖ said Nancy Stoner, acting assistant
administrator for EPA‘s Office of Water. ―The public‘s comments will be instrumental in
shaping safeguards for aquatic life and to build a commonsense path forward. The input
we receive will make certain that we end up with a flexible and effective rule to protect the
health of our waters and ecosystems.‖ Safeguards against impingement will be required
for all facilities above a minimum size; closed-cycle cooling systems may also be required
on a case by case basis when, based on thorough site-specific analysis by permitting
authorities, such requirements are determined to be appropriate. EPA is proposing this
regulation as a result of a settlement agreement with Riverkeeper, Inc. and other
environmental groups.
Flexible Technology Standards:
Fish Impingement (Being pinned against screens or other parts of a cooling water intake
structure): Existing facilities that withdraw at least 25 percent of their water exclusively for
cooling purposes and have a design intake flow of greater than 2 million gallons per day
(MGD) would be required to reduce fish impingement under the proposed regulations. To
ensure flexibility, the owner or operator of the facility will be able to choose one of two
options for meeting best technology available requirements for reducing impingement.
They may conduct monitoring to show the specified performance standards for
impingement mortality of fish and shellfish have been met, or they may demonstrate to the
permitting authority that the intake velocity meets the specified design criteria. EPA
estimates that more than half of the facilities that could be impacted by this proposed rule
already employ readily available technologies that are likely to put them into compliance
with the proposed standard.
Fish Entrainment (Being drawn into cooling water systems and affected by heat, chemicals
or physical stress): EPA is proposing a site-specific determination to be made based on
local concerns and on the unique circumstances of each facility.
This proposed rule establishes requirements for the facility owner to conduct
comprehensive studies and develop other information as part of the permit application,
and then establishes a public process, with opportunity for public input, by which the
appropriate technology to reduce entrainment mortality would be implemented at each
facility after considering site-specific factors. Because new units can incorporate the most
efficient, best-performing technology directly into the design stage of the project, thus
lowering costs and avoiding constraints associated with technology that has already been
locked in, the proposed rule would require closed-cycle cooling (cooling towers) for new
units at existing facilities, as is already required for new facilities. The proposal will be
open for public comment for 90 days upon its publication in the Federal Register. The
administrator must take final action by July 27, 2012. Further information is available at:
Environmental Protection Agency, 28 March 2011 http://www.epa.gov

Congress reviews U.S. nuclear plant practices
Recently, the U.S Congress discussed the Japanese disaster and its impact on the U.S.
nuclear power industry. The safety of spent fuel pools was the focus of a subcommittee
hearing of the Senate Appropriations Committee. Subcommittee Chair Senator Dianne
Feinstein (D-Calif.) urged NRC to require U.S. reactor owners to more quickly move spent
fuel from pools to above-ground storage canisters. NRC maintains that pool storage is
safe but acknowledges that the practice will be included in its review of lessons learned
from the Japan disaster. Peter B. Lyons, a nuclear energy administrator at the Department
of Energy, noted for the subcommittee that the fate of radioactive waste is under
examination by DOE and NRC, as well as by the presidential Blue Ribbon Commission on
America‘s Nuclear Future. That panel was set up to examine the fate of nuclear waste in
light of an Obama Administration decision to halt consideration of the Yucca Mountain
nuclear waste repository in Nevada. The commission‘s draft report is expected in late July,
Lyons noted.
Chemical & Engineering News, 4 April 2011 http://pubs.acs.org/cen/news

CSB Chairperson Calls on Industry to Invest in Preventive Maintenance
Marking the one year anniversary of the tragic accident at the Tesoro Refinery in
Anacortes, Washington, the U.S. Chemical Safety Board (CSB) have released a video
safety message in which Chairperson Rafael Moure-Eraso urges refinery companies to
―make the investments necessary to ensure safe operations,‖ concluding, ―Companies that
continue to invest in safety and recognise its importance will reap benefits far into the
future.‖ The video, which can be found at http://www.csb.gov/, highlights the CSB‘s
ongoing investigation into the 2 April 2010, accident that killed seven workers. At the time
of the incident, a heat exchanger was being brought online when the nearly forty-year-old
piece of equipment catastrophically failed, spewing highly flammable hydrogen and
naphtha, which ignited and exploded. In the safety message CSB Chairman Moure-Eraso
notes, ―The Tesoro accident is only one of several fatal incidents that occurred in the oil
and gas production and refining sector in 2010 alone. Serious incidents at refineries
continue to occur with alarming frequency.‖ Such incidents can be avoided, said
Moure-Eraso, if employers:
Implement a robust mechanical integrity programs with an emphasis on thorough
inspections of critical equipment.
Monitor process safety performance using appropriate leading and lagging indicators to
measure process safety before major accidents occur.
Maintain an open and trusting safety culture where near-misses and loss of containment
incidents are reported and investigated.
CSB‘s safety message notes leading insurance industry statistics indicating that the U.S.
refining sector has more than three times the rate of property losses of refineries overseas.
The CSB is an independent federal agency charged with investigating serious chemical
accidents. The agency‘s board members are appointed by the president and confirmed by
the Senate. CSB investigations investigate all aspects of chemical accidents, including
physical causes such as equipment failure as well as inadequacies in regulations, industry
standards, and safety management systems. The board does not issue citations or fines
but does make safety recommendations to plants, industry organisations, labour groups,
and regulatory agencies such as OSHA and EPA. CSB‘s final report including can be
viewed at http://www.csb.gov.
EHS Today, 4 April 2011 http://www.ehstoday.com

Canada proposes significant new activity controls for three Batch 3 substances
Recently, the Canadian government published a notice of intent to amend the Domestic
Substances List to apply significant new activity provisions of the Environmental Protection
Act to three substances included in batch 3 of its Challenge Program. The substances are:
Ethanol, 2-methoxy-, acetate (2-MEA)
Ethanol, 2-(2-methoxyethoxy)- (DEGME)
2-Naphthalenol, 1-[4-methyl-2-nitrophenyl)azo]- (Pigment Red 3)
The proposal is now open for public comment until 1 June 2011. A copy of the proposal is
available at:
Chemical Watch, 4 April 2011 http://chemicalwatch.com/news

Commission’s nano policy lost in definition
It has recently emerged that the European Commission‘s hesitance to define
nanotechnology underscores diverging opinions among stakeholders and is causing
uncertainty in the sector. Nanotechnologies use materials on an incredibly small scale.
The unique properties and behaviour of nanoscale matter, and its enabling characteristics,
mean new technologies could profoundly transform industry and everyday life. However,
concerns have been raised over the ethical, legal and health issues associated with
nanotechnologies. The European Parliament, in a resolution of 24 April 2009, called on the
Commission to strive for an internationally harmonised definition of the term nanomaterial.
Last October, the Commission released a draft definition for consultation. The consultation
ended in November last year, but the Commission has yet to publish a final definition.
Such a definition will play a vital role in any future policy development relating to
nanotechnology. The Commission is currently considering a new Action Plan for
Nanotechnology, addressing the technological and societal challenges of the next five
years. A separate consultation on the Action Plan ended in February this year. Participants
in a Brussels-based international conference, the Safety for Success Dialogue, discussed
the Commission‘s ongoing search to revise a draft definition of nano that went out to public
consultation last year, but made clear that no answer has yet been found. Henrik Laursen,
coordinator of the nano team in the Commission‘s environment department, said the EU
executive had received around 200 replies to the consultation. He said: ―It is clear that at a
certain level many stakeholders are saying different things, and there is no absolute
scientific definition.‖ He said the Commission would not be rushed into making a decision
because, once made, it would not be a working model but would immediately have a
significant binding effect. However, Chiara Giovanini, a spokeswoman for ANEC, the
European Consumer Voice in Standardisation, noted that the ―lack of an agreed definition
is creating legal uncertainties for regulatory purposes, and hindering the development of
adequate safety test and measurement methods‖. She called on the Commission to adopt
the draft definition of nanomaterials contained in the consultation at the end of last year
―without further delay‖. Laursen said that although the Commission would consider the
public consultation and the advice of key scientific bodies such as the EU‘s scientific
committee on emerging and newly identified health risks (SCENIHR), ultimately the
definition would be ―a policy decision‖. The Commission is believed to be attempting to
frame a definition before the end of the summer. However, the finer detail of how to define
nanomaterials is the subject of fervent disagreement between stakeholders behind the

Wim de Jong, vice-chair of the SCENIHR, said that his organisation had recommended to
the Commission that the number of particles, rather than the weight of the particles, be
used as a guide for determining the definition. ―This is important because the potential
hazards of using these particles relates to the number of them within a particular product,‖
he said. But other stakeholders are opposed to using numbers as a guide to defining
nanomaterials. For example, the European Chemical Industry Council (Cefic) has
recommended to the Commission that weight be used instead. Cefic‘s reply to the
Commission consultation reads: ―Weight is generally used in all chemical legislation and
test procedures and should therefore be used instead of particle number concentration.‖
Carlos Peña, director of emerging technology programmes in the office of the chief
scientist at the US Food and Drug Administration, the US consumer regulator, said that the
US had not defined nanotechnologies and was instead trying to keep watch over how they
are introduced into several different sectors – such as food, drugs and cosmetics – to
ensure that regulation within those sectors takes account of their use. Henrik Laursen,
coordinator of nano team at the European Commission‘s environment department, said:
―We still have some decisions to take but what we will come up with eventually will not be
a working definition, it will be a definition that will be applicable [...] There is no room for us
to introduce a definition by trial and error, we are expected to make sure we act and we
need to come up with something.‖ Laursen said that within the draft definition provided by
the Commission there was a review clause ―so there is a possibility to return to the issue to
see if we got it right‖. He added: ―The definition will not and cannot solve all the issues, but
it will be the beginning of the process.‖ Qasim Chaudry, the principal research scientist at
the UK Food and Environment Research Agency, said his agency was currently
considering the first case of nano ingredients that would become available for consumer
use in the cosmetics industry. The outcome of this case would, he said, ―set a precedent
for future assessment‖. He added: ―The challenges include the fact that there is no
definition of nanotechnology, and the fact that we are setting new systematic standards for
dealing with nano.‖ Chiara Giovanini, a spokeswoman for ANEC, said: ―We support the
proposed science-based approach according to which the size distribution of a material
should be presented as size distribution based on the number concentration (i.e. the
particle number), and not on the mass concentration of a nanomaterial product. This is
because a small mass concentration may contain the largest number fraction.‖ She added:
―Materials on this scale present different properties compared with ‗bigger‘ particles (e.g.
greater reactivity and mobility in the body) and are increasingly being used to create new
products. Products claiming to contain nanomaterials are already widely available on the
European market and it is imperative to ensure that they are safe for consumers to buy.
We believe that the starting point of any sound regulatory approach is agreement on a
definition of what exactly nanomaterials and nanotechnologies are.‖
Euractiv, 1 April 2011 http://www.euractiv.com

In vitro screening method “shows promise” for DNT testing
The European Commission‘s Joint Research Centre (JRC) has drawn attention to
research which, it says, shows that ―primary cortical neurons could be a promising in vitro
model for developmental neurotoxicity (DNT) testing‖. According to the JRC, the authors
examined ―one of the most promising tools for neurotoxicity assessment, which is the
measurement of neuronal electrical activity using micro-electrode arrays‖. The JRC
statement is available at:
Chemical Watch, 5 April 2011 http://chemicalwatch.com/news

EU publishes Regulation on construction products
The recently agreed regulation laying down harmonised conditions for the marketing of
construction products has been published in the Official Journal. Companies placing
products on the market will have to provide information required by articles 31 or 33 of the
REACH Regulation in the products‘ declarations of performance. These had to be
provided under the previous directive, and will be a continuing requirement of the new
Regulation. This provision would apply from 1 July 2013. Full details can be found in the
Official Journal:
Chemical Watch, 4 April 2011 http://chemicalwatch.com/news

REACH Update
ECHA publishes an update of the Guidance on Substances in Articles
On 1 April the European Chemicals Agency (ECHA) issued an update to the Guidance on
Requirements for Substances in Articles. The update replaces the previous guidance
document. From 1 June 2011, companies may have to notify to ECHA Substances of Very
High Concern (SVHC) on the Candidate List that are present in articles they produce or
import. The guidance describes the registration, notification and communication
requirements related to substances in articles and helps producers, importers and
suppliers of articles to identify and fulfil their legal obligations. It further clarifies the
decision-making process as to whether an object is an article. The new guidance explains
how to check if a substance is already registered for a use and therefore whether a
registration or notification is needed. Examples of borderline cases such as blasting grits
and wax crayons are given in the guidance. It also explains how companies can predict
the inclusion of substances in the Candidate List for authorisation. Further information is
available at: http://guidance.echa.europa.eu/
ECHA, 4 April 2011 http://echa.europa.eu

REACH and CLP terminology in 22 EU languages available now online
A test version of a multilingual terminology database provides the main REACH and CLP
terms in 22 EU languages, including the CLP pictograms, hazard and precautionary
statements. On 5 April 2011, the European Chemicals Agency (ECHA) announced the
database is now online, free of charge. ECHA launched a terminology project in 2009 to
improve the quality of the translations of its documents and to provide companies with a
multilingual terminology tool to facilitate communication in the supply chain. The database
is now available for final testing. Users can provide feedback by carrying out simple
exercises and reporting their experiences between 5 to 13 April. Two User Groups,
consisting of the representatives from the Member States Competent Authorities, industry,
ECHA, EU bodies and translators, have already tested previous versions last year and
found it very useful in their work. The database can be used by companies to help in the
preparation of safety data sheets in multiple languages.
The database offers:
Around 900 REACH and CLP terms, phrases and definitions
Pictograms for 9 CLP hazard classes
6 substances of very high concern (as a test)
Alphabetical index containing all entries
Search preferences with the possibility to customise the interface
Help section
Possibilities for registered users to download the terminology, comment on entries and
receive news on the database updates
ECHA‘s terminology database can be used free of charge. The registration is required only
for the users who would like to download or comment the data. The database is managed
for ECHA by the Translation Centre for the Bodies of the EU (CdT) in Luxembourg. To
access the multilingual database go to: http://echa.cdt.europa.eu
ECHA, 5 April 2011 http://echa.europa.eu

ECHA revises its Guidance Consultation Procedure
The revised Guidance Consultation Procedure is largely based on ECHA‘s original
procedure and takes due account of the lessons learnt from the first years of experience
regarding updating guidance documents. Key elements of the revision are:
a physical meeting of the Partner Expert Groups as a standard element of the consultation
the involvement of the Committees and/or Forum on a more ad-hoc basis allowing for an
accelerated procedure;
a simplified process for nominating experts for the Partner Expert Groups and further
clarification of their role;
a further clarification of ECHA‘s practice regarding translation of guidance documents;
the removal of the potential final step of seeking the advice of the Management Board in
case of dissenting views expressed through the oral or written consultation of Member
States or the Commission;
the removal of the option of including footnotes referring to Member States‘ dissenting
positions on certain passages in the guidance;
introduction of a note to the reader signed by the Executive Director when publishing
guidance documents which did not receive support from all EU/EEA Member States,
simultaneously warning that companies may face diverging enforcement practices.
Guidance updates or new guidance documents that have not yet been initiated will be
established according to this new procedure. The new procedure will be gradually
implemented for those updates that have already been started. ECHA says that the main
advantage of the new procedure is that it will be able to accelerate the process of
guidance development or updating so as to be able to process the updates linked to
registration in good time ahead of the next registration deadline. Further details on the
Revised Consultation procedure on Guidance are available at:
ECHA, 5 April 2011 http://echa.europa.eu

ECHA publishes new tools for preparation and submission of Authorisation
Recently ECHA updated its web section on applications for authorisation. The web section
now includes web forms for dossier submission and templates for dossier preparation.
Application dossiers for authorisation need to be created using the newest version of
IUCLID5. ECHA has updated its web section on applications for authorisation to provide
companies with further tools to prepare and submit an application. In particular, templates
to document an analysis of alternatives, a socio-economic analysis and a substitution plan
have been made available. Potential applicants can also find a Fee Calculator to estimate
the fee related to their applications. In addition, ECHA has published new specific web
forms for applicants to prepare and submit their applications for authorisation. A new Data
Submission Manual explains in detail how to prepare an Application for Authorisation using
IUCLID 5.3, and how to use the web forms for dossier submission. For further information
go to ECHA‘s website.
ECHA, 5 April 2011 http://echa.europa.eu

Janet’s Corner – Not too seriously!
The patient
A man is in a hospital bed completely wrapped up in a body cast. One of the nurses gave
him a rectal thermometer and said, ―Don‘t move, I‘ll be right back.‖
When she returned the thermometer was in his mouth. She asked in amazement, ―How
did you get that in your mouth, you can‘t even move?‖
Then the man said, ―I hiccupped.‖
Please note: articles for Janet‘s Corner are not original, and come from various sources.
Author‘s credits are supplied when available.

This soft grey metal resembles tin but discolours when it is exposed to air. [1]
Approximately 60–70% of thallium production is used in the electronics industry, and the
rest is used in the pharmaceutical industry and also glass manufacturing. Thallium is also
used in infrared detectors. It is highly toxic and was previously used in rat poisons and
insecticides. Its use has been cut back or eliminated in many countries because of its
non-selective toxicity. Because of its use for murder, thallium has gained the nicknames
―The Poisoner‘s Poison‖ and ―Inheritance Powder‖. [1]
Thallium is extremely soft and malleable and can be cut with a knife at room temperature.
It has a metallic lustre, but when exposed to air, it quickly tarnishes with a bluish-grey tinge
that resembles lead. It may be preserved by keeping it under oil. A heavy layer of oxide
builds up on thallium if left in air. In the presence of water, thallium hydroxide is formed.
Sulphuric and nitric acid dissolve thallium rapidly to make the sulphate and nitrate salts,
while hydrochloric acid forms an insoluble thallium chloride layer. [1]


Thallium bromide and thallium iodide crystals have been used as infrared optical materials,
because they are harder than other common infrared optics, and because they have
transmission at significantly longer wavelengths. Thallium oxide has been used to
manufacture glasses that have a high index of refraction. Combined with sulphur or
selenium and arsenic, thallium has been used in the production of high-density glasses
that have low melting points in the range of 125 and 150°C. These glasses have room
temperature properties that are similar to ordinary glasses and are durable, insoluble in
water and have unique refractive indices. [1]

Sulphide‘s electrical conductivity changes with exposure to infrared light therefore making
this compound useful in photoresistors. Thallium selenide has been used in a bolometer
for infrared detection. Doping selenium semiconductors with thallium improves their
performance, and therefore it is used in trace amounts in selenium rectifiers. Another
application of thallium doping is the sodium iodide crystals in gamma radiation detection
devices. In these, the sodium iodide crystals are doped with a small amount of thallium to
improve their efficiency as scintillation generators. Some of the electrodes in dissolved
oxygen analysers contain thallium. [1]

Research activity with thallium is ongoing to develop high-temperature superconducting
materials for such applications as magnetic resonance imaging, storage of magnetic
energy, magnetic propulsion, and electric power generation and transmission. [1]

Some people who drink water containing thallium well in excess of the maximum
contaminant level (MCL) for many years could experience hair loss, changes in their blood,
or problems with their kidneys, intestines, or liver.

Thallium and its compounds are extremely toxic, and should be handled with great care.
There are numerous recorded cases of fatal thallium poisoning. Contact with skin is
dangerous, and adequate ventilation should be provided when melting this metal. Thallium
compounds have a high aqueous solubility and are readily absorbed through the skin.
Exposure to them should not exceed 0.1 mg per m2 of skin in an 8-hour time-weighted
average (40-hour work week). Thallium is a suspected human carcinogen. For a long time
thallium compounds were easily available as rat poison. This fact and that it is water
soluble and nearly tasteless led to frequent intoxications caused by accident or criminal
Treatment and internal decontamination
One of the main methods of removing thallium (both radioactive and normal) from humans
is to use Prussian blue, which is a material which absorbs thallium. Up to 20g per day of
Prussian blue is fed by mouth to the person, and it passes through their digestive system
and comes out in the stool. Haemodialysis and haemoperfusion are also used to remove
thallium from the blood serum. At later stage of the treatment additional potassium is used
to mobilise thallium from the tissue.


Exposure to Chemicals in Environment Associated With Onset of Early Menopause
A recent study accepted for publication in The Endocrine Society‘s Journal of Clinical
Endocrinology & Metabolism (JCEM) found that higher levels of perfluorocarbons (PFCs)
in the body are associated with increased odds of having experienced menopause in
women between 42 and 64 years old. Women in this age group with high levels of PFCs
also had significantly lower concentrations of oestrogen when compared to women who
had low levels of PFCs. PFCs are human-made chemicals used in a variety of household
products including food containers, clothing, furniture, carpets and paints. Their broad use
has resulted in widespread dissemination in water, air, soil, plant life, animals and humans,
even in remote parts of the world. A probability sample of U.S. adults, found measurable
concentrations of PFCs in 98 percent of the participants tested. ―The current study is the
largest ever to be done on the endocrine-disrupting effects of perfluorocarbons in human
women,‖ said Sarah Knox, PhD, of the West Virginia University School of Medicine in
Morgantown and lead author of the study. ―Our data shows that after controlling for age,
women of perimenopausal and menopausal age in this large population are more likely to
have experienced menopause if they have higher serum concentrations of PFCs than their
counterparts with lower levels.‖ During the current study of 25,957 women aged 18 to 65
years, researchers ascertained menopausal status of participants and then measured their
serum concentration levels of PFCs and oestradiol. They found that there was an
association between PFC exposure, decreased oestradiol and early menopause in women
over age 42. There was also an inverse association between PFC levels and oestradiol in
women of child bearing age but this association was not statistically significant. ―There is
no doubt that there is an association between exposure to PFCs and onset of menopause,
but the causality is unclear,‖ said Knox. ―Part of the explanation could be that women in
these age groups have higher PFC levels because they are no longer losing PFCs with
menstrual blood anymore, but, it is still clinically disturbing because it would imply that
increased PFC exposure is the natural result of menopause.‖ PFCs are known to have
multiple adverse health outcomes including increased cardiovascular risk and impairment
of the immune system. ―Our findings suggest that PFCs are associated with endocrine
disruption in women and that further research on mechanisms is warranted,‖ said Knox.
Science Daily, 29 March 2011 http://www.sciencedaily.com

Spreading Resistance During Wastewater Treatment
When people pop antibiotics to treat infections, the drugs often end up excreted into
sewage. As scientists continue to find these antibiotics in the wastewater coming from
homes and hospitals, they are concerned that the drugs‘ presence is fuelling the spread of
antibiotic resistance. At the American Chemical Society meeting in Anaheim, California,
researchers reported that wastewater contains other chemicals that might also promote
antibiotic resistance: heavy metals. Previously, environmental scientists have observed a
connection between metals and antibiotic resistance in metal-contaminated soils and
freshwater sediments. The bacteria living in these environments had significantly higher
levels of resistance than bacteria from noncontaminated soils. Edward F. Peltier of the
University of Kansas, Lawrence; David Graham of Newcastle University, in England; and
their colleagues wondered if the phenomenon also occurred in wastewater treatment
plants. These plants are a unique environment where, along with antibiotics, metals such
as zinc and copper are common. Furthermore, bacteria play a major role in the treatment
process. After removing solids from wastewater, treatment plants mix it with a sludge
containing an array of bacteria that chew up dissolved organic compounds. During the new
study, Peltier and his team simulated that process, called activated sludge treatment, to
determine whether metals could spread antibiotic resistance. They constructed lab-scale
versions of the sludge reactors from inverted 4-L glass bottles with their bottoms cut off.
Each reactor started with water containing a mix of organic molecules and other nutrients
commonly found in wastewater, along with bacteria from wastewater samples collected
from a nearby treatment plant. After allowing the bacteria to grow, the researchers put their
collection of minireactors through three experimental phases. In the first phase, they
monitored baseline levels of antibiotic resistance in the sludge bacteria. The scientists next
added metals, either copper or zinc, to some of their reactors and monitored any changes
in resistance. For the third phase, they added one of three antibiotics to each reactor.
Throughout the experiment, the researchers monitored the levels of dissolved organic
material to ensure that the reactors were running efficiently. The results showed that
copper alone, in the absence of antibiotics, could promote resistance to the antibiotic
ciprofloxacin, with resistance levels jumping from a baseline level of 7% of the reactor
population after the first phase to 11% after the second phase. Zinc alone didn‘t have an
effect, but in the presence of certain antibiotics it did enhance resistance levels. In reactors
receiving zinc and tetracycline, 63% of the bacteria were resistant to the antibiotic.
Meanwhile, resistance levels in reactors that received tetracycline and no metal were only
44%. If metals do help spread antibiotic resistance in wastewater treatment plants, then
they could be a more long-lasting source of resistance than are antibiotics themselves,
Peltier says. ―Antibiotics can degrade, metals can‘t,‖ he says. Rolf U. Halden of Arizona
State University, Tempe, calls the study ―a great example of how environmental
engineering and environmental chemistry intersect with a major issue in human health.‖
He thinks that the results raise questions about how we deal with industrial wastewater,
which contains significant levels of metals. Treatment plants often mix this water with
domestic sewage, bringing antibiotics and metals together. Removing metals from
industrial wastewater before it reaches these plants could minimize the problem, he says.
Chemical & Engineering News, 28 March 2011 http://pubs.acs.org/cen/news

Diabetes tied to higher Parkinson’s disease risk
According to the findings of a new study, people with diabetes may have a slightly
increased risk of developing Parkinson‘s disease, though the reasons for the link,
researchers say, are far from clear. The new study, of nearly 289,000 older U.S. adults,
found that those with diabetes at the outset were more likely to be diagnosed with
Parkinson‘s over the next 15 years. Out of 21,600 participants with diabetes, 172 (0.8
percent) were eventually diagnosed with Parkinson‘s. That compared with 1,393 cases
(0.5 percent) among the 267,000 men and women who were diabetes-free at the
beginning of the study. When the researchers adjusted for the confounding factors -- like
age, weight and smoking habits -- diabetes itself was linked to a 41 percent increase in the
risk of future Parkinson‘s. That, however, does not prove that diabetes is a cause of
Parkinson‘s, and the reasons for the connection remain unknown, said senior researcher
Dr. Honglei Chen, of the U.S. National Institute of Environmental Health Sciences. ―Really,
the evidence at this time is very preliminary,‖ Chen said. People with diabetes, he said,
should simply continue to do the things already recommended for their overall health --
eating a well-balanced diet and getting regular exercise. Chen and his colleagues reported
the findings in the journal Diabetes Care. Diabetes and Parkinson‘s disease would seem,
at first, to be unrelated. Diabetes arises when the body can no longer properly use the
blood-sugar-regulating hormone insulin. Parkinson‘s is a brain disease in which
movement-regulating cells in the brain die off or become disabled, leading to symptoms
like tremors, rigidity in the joints, slowed movement and balance problems. But Chen said
the connection between diabetes and Parkinson‘s risk could mean that the two diseases
share some underlying mechanisms. One possibility, he speculated, is chronic, low-level
inflammation throughout the body, which is suspected of contributing to a number of
chronic diseases by damaging cells. Oxidation - the process fought by anti-oxidants - is
another. On the other hand, Chen and his colleagues say, there might be something about
diabetes - like a problem regulating insulin -- that contributes to Parkinson‘s. But that
remains to be proven. A few large studies have investigated the diabetes-Parkinson‘s link
before, with conflicting results. The current study, Chen said, included a larger number of
people with Parkinson‘s. And unlike most past studies, it looked at the duration of people‘s
diabetes. In general, Chen‘s team found, the higher Parkinson‘s risk was largely seen
among people who‘d had diabetes for more than 10 years before the start of the study.
According to Chen, this supports the idea that diabetes came first, before Parkinson‘s,
rather than the other way around. However, the researchers says that further research is
required in order to understand why the connection exists, and what, if anything, can be
done about it
Reuters Health, 30 March 2011 http://www.reuters.com/news/health

Sulphur-Eating Bacteria Sense Water Pollutants
When factories accidentally release dangerous chemicals into waterways, scientists need
an early warning system so that they can mitigate environmental damage. Now in a new
study, researchers have demonstrated that a bacterium commonly found in wastewater
sludge can sound the alarm when toxic water pollutant levels rise. Oxidised contaminants
such as nitrates, perchlorate, and chromate enter waterways from fertilisers, explosives,
and manufacturing processes. At high concentrations, these chemicals harm fish, animals,
and people. To detect such chemicals, scientists usually monitor changes in the
physiology or bioluminescence of certain microorganisms, but such assays often require
specialised equipment and are labour intensive and slow. What‘s more, explains Steven
Van Ginkel, a research scientist at the Swette Centre for Environmental Biotechnology at
Arizona State University, Tempe, ―Most sensors are specific to just one chemical, but the
toxicity of individual chemicals is additive.‖ So Van Ginkel, Sang-Eun Oh, an
environmental biologist at Kangwon National University, in South Korea, and their
colleagues wanted to develop a bacterial biosensor that detects the overall toxicity of
oxidised pollutants. The researchers speculated if Acidithiobacillus, a genus of bacteria
found in wastewater sludge, could provide a simple, comprehensive readout. This
bacterium eats elemental sulphur and, in the presence of oxygen and water, catalyses its
conversion to sulphate and protons. The researchers reasoned that oxidised contaminants
would inhibit this reaction by crippling bacterial enzymes. The bacteria then would
generate less SO42- and H+. So the researchers could detect the contaminants by the
resulting drop in the electrical conductivity or rise in pH of the solution surrounding the
bacteria. In order to test their theory, the team added sulphur particles and simulated
stream water to sludge from a Korean wastewater treatment plant and bubbled oxygen
through the mixture. Under these conditions, Acidithiobacillus bacteria thrived, whereas
most other bacteria in the sludge died. When the researchers introduced water containing
oxidised contaminants to the biosensor, the pH and conductivity of the liquid changed
substantially within minutes to hours, depending on the type and concentration of
contaminant. Measurable change occurred with as little as 5 parts per billion of chromate.
The new method is faster and more sensitive than existing biosensors, the researchers
say. Moreover, detection requires only a simple conductivity or pH meter, which is
standard equipment for most environmental labs. According to Van Ginkel, scientists at
riverside detection stations could use the bacteria to monitor contaminants in real time: All
they would need is a pump to introduce river water into the bacterial reactor. ―Any change
in pH or electrical conductivity would let us know that some type of toxic event occurred,
which could help us protect fish and people downstream,‖ he says. Kim Rogers, a
research chemist at the U.S. Environmental Protection Agency‘s National Exposure
Research Laboratory, calls Van Ginkel and Oh‘s technique ―novel‖ and ―potentially useful.‖
However, Rogers says that ―commercial successes for environmental bioanalytical
methods are not particularly common.‖ Yet this track record hasn‘t stopped Oh from
patenting the technology, which he hopes to commercialise soon.
Chemical & Engineering News, 25 March 2011 http://pubs.acs.org/cen/news

Diet high in fish linked to stronger bones
A new study has discovered that older adults who eat greater amounts of fish end up
preserving their bone density better than people who don‘t eat as much fish. The study
doesn‘t prove that such habits strengthen bones, but researchers believe that the
combination of different oils in the fish protects bones from losing mass over time. ―We
think omega 3 fatty acids from fish help to prevent bone loss‖, said lead researcher Dr.
Katherine Tucker, a professor at Northeastern University. However, her study finds that
preventing bone loss is not as simple as upping the levels of omega 3 fats in people‘s diet.
During the new research, her team examined surveys, collected in the 1980s and 90s, of
the eating habits of more than 600 seniors who lived in Framingham, Massachusetts.
Measurements of the bone density in their hips were taken 4 years apart. Women who ate
three or more weekly servings of dark fish, such as salmon or mackerel, had smaller
amounts of bone loss 4 years later, compared to women who ate less fish. In addition, the
researchers observed that men who ate dark fish or tuna at least three times per week
also had less bone loss than other men. The study was unable to show that fish was the
cause of the differences in bone loss, but merely that the two are associated. Fish are rich
in the omega 3 fatty acids, EPA and DHA. Further investigating what people ate, the
researchers broke down how much of both omega 3 and omega 6 fatty acids people were
getting in their diet. They found that it‘s not just the omega 3s that are involved in bone
density. High levels of an omega 6 fatty acid, called arachidonic acid, was linked to less
bone loss in women - but only when women also consumed higher levels of omega 3 fats.
―It looks like you need to have those in a good balance,‖ Tucker said. ―If you have very low
levels of arachidonic acid, then you didn‘t see the benefits of the omega 3s.‖ ―You can‘t
just take a supplement of one and have a good effect,‖ Tucker added. Too much of one fat
could actually be harmful. In men, high arachidonic acid and low omega 3s was tied to
greater loss of bone. Tucker said there‘s no exact formula yet of omega 3 and omega 6
fats that would be good for bone health. Fish appears to provide a good balance, Tucker
said, because it has the omega 3 fats that tend to be lacking in Western diets. Omega 6
fatty acids are typically abundant in the food Americans eat. The American Heart
Association recommends that people eat two servings of fish each week. Tucker‘s study
was published in the American Journal of Clinical Nutrition. Bone loss is a normal part of
aging, and less dense bones are at a greater risk of breaking. This study did not examine
whether the differences in bone loss between frequent fish-eaters and others make any
difference in the risk of breaking bones.
Reuters Health, 30 March 2011 http://www.reuters.com/news/health

Dark chocolate’s good and good for you, a study finds
Eating a dark chocolate bar may improve visual and cognitive functions – at least
temporarily. Visual sensitivity – the ability to see in difficult conditions – was enhanced up
to two hours later in people who ate the chocolate as part of a study. The results highlight
the potential health benefits derived from dark chocolate and suggest new avenues of
research. Flavanoids are a class of naturally occurring plant compounds being studied as
dietary aids for healthy ageing. Several types are found in the human diet, including the
flavanols. Grapes, red wine, green tea and cocoa all contain flavanols. There is increasing
interest in the health effects – including heart and brain benefits – associated with
flavanols. Exactly how they benefit health is not known. They may act as antioxidants, and
they may increase the production of nitric oxide gas (Fraga et al. 2011). Nitric oxide has
many actions in the body. It controls blood vessel expansion – called vasodilation – which
increases blood flow and decreases blood pressure. Cocoa beans – the building block of
many chocolate treats – are naturally rich in flavanols. In general, darker chocolates
contain the highest levels of these compounds. Milk chocolate and other overly processed
chocolates have less because the sweetening can strip away up to 90 percent of the
flavanols from the bean. Previous research suggests that eating dark chocolate provides
positive benefits for the heart and might lower blood pressure (Mehrinfar and Frishman
2008). For instance, some studies find nitric oxide levels increase and blood pressure
declines in people after they eat cocoa flavanols. Few studies have tested cocoa flavanols
for cognitive benefits. Those that have find specific short-term effects. In one study, blood
flow to the brain increased after drinking a cocoa drink with 150 milligrams of flavanols for
five days (Francis et al. 2006). Cocoa did not induce changes in reaction time nor error
rate on a behavioural flexibility task in this study. A separate study did find a short-term
improvement in the participants‘ performance of a working memory task and in their
reported mental fatigue after a series of tests after they drank a cocoa drink with 520
milligrams of cocoa flavanols (Scholey et al. 2010).

The potential role for cocoa flavanols on vision has not been studied. Supporting evidence
from other studies with glaucoma and ginko biloba – which is high in flavanoids – hint that
the compound may affect sight by increasing blood flow to the eye. During the new study,
the researchers from the University of Reading examined the visual and cognitive effects
of cocoa flavanols. In the study, 30 18- to 25-year-olds ate a dark chocolate bar (CHOXI+)
containing 773 milligrams cocoa flavanols during one test session and a white chocolate
bar containing none at a second test session a week later. Two hours after eating the bar
at each session, they were tested on visual, memory and reaction time tasks. One visual
task assessed the ability to read as light conditions change – called contrast sensitivity.
After participants correctly read a set of numbers on a screen the light contrast was
lowered to make the numbers more difficult to read. The contrast was again lowered after
each correct response until neither of the digits was read correctly. Other sets of visual
tests used moving dots. Participants identified their direction and their pattern – either
horizontal or random. Cognitive skills were assessed through memory and reaction time
tests. For memory, the participants were asked to identify which objects had changed
locations from one screen to another. The reaction time task required participants to
quickly press one of three keys associated with a number or two letters that flashed on the
computer screen. Two hours after eating the dark chocolate bar, the participants‘ visual
and cognitive abilities improved when compared to those who ate the white chocolate
without flavanols. Dark chocolate eaters were about 17 percent better able to discern
objects in contrasting light conditions. They were able to read numbers at lower contrast
levels than those eating white chocolate. They also more quickly identified whether a
series of dots was moving horizontally or in a random pattern. For working memory, those
who ate a dark chocolate bar correctly identified more of the objects that had switched
places than those eating white chocolate. Their times to correctly press a key in response
to letters or numbers were also shorter. Performance on visual and cognitive tasks
improve after eating a single serving of a commercially available dark chocolate that
contains a moderate amount of cocoa flavanols. This is the first study to show that eating
dark chocolate can result in improved performance on visual function tests. In addition, the
study supports previous research that documents positive effects on the performance of
memory tasks after ingesting cocoa flavanols. These findings also extend these positive
effects to a reaction time task. The effects on vision – as measured through contrast
sensitivity – suggest cocoa flavanols have positive effects in some challenging visual
conditions, such as working in a low light environment. Older adults often report a decline
in contrast sensitivity. The results open up the possibility that flavanols could have a
similar effect in older adults.

A short-term enhancement in working memory and reaction time also was reported. These
– along with the visual improvements – suggest a general underlying mechanism.
Although not measured in this study, the authors suggest the effects may be the result of
increased blood flow to the eye and the brain. Cerebral blood flow is increased two hours
after consuming cocoa flavanols, but effects on blood flow to the eye are not known. Can
chocolate now be considered a health food? Chocolate is still high in fat and calories. Yet
a growing body of research suggests possible positive health effects of eating cocoa and
chocolate products. Importantly, one to two ounces of dark chocolate can contain a
significant amount of cocoa flavanols – anywhere from 100 to 200 milligrams, but these
levels do vary from product to product (Miller et al. 2009). While the study did not directly
look at supplements, the results offer the possibility that cocoa flavanol supplements may
be beneficial. Animal studies suggest this as well. Until appropriate research is conducted,
the potential health benefits and risks of flavanol supplements remain unknown. It is
important to note that the dark chocolate bars eaten in this study also contained other
ingredients – including caffeine – which were not in the white chocolate bars. A previous
study showed working memory improved after drinking cocoa with the flavanols when
compared to drinks with equal nutritional components – including caffeine – but without the
cocoa flavanols (Scholey et al. 2010). Although the current study is only a preliminary one,
the potential influence of caffeine on the outcomes of this research cannot be ruled out
and need further investigation. Based on the findings, consuming products containing
cocoa flavanols may provide some visual and cognitive benefits. More work is needed to
understand the extent of these improvements. To date, the evidence for health benefits of
eating cocoa products is only from short-term and observational studies. Accumulating
evidence does show that dark chocolate and other cocoa products may have health
benefits, but the question of how little or how much is good for you remains unanswered.
Environmental Health News, 29 March 2011 http://www.environmentalhealthnews.org/

Japan nuclear crisis may have a silver lining for radiation health research
No one is happy that the Fukushima Daiichi power plant is still releasing dangerous levels
of radioactive particles more than two weeks after a magnitude 9 earthquake and the
resulting tsunami knocked out the crucial cooling systems that maintain the nuclear fuel at
safe temperatures. However, all clouds have a silver lining, as the saying goes. And in this
case, that silver lining might be a renewed focus on the long-term health effects of the
1986 Chernobyl disaster. The explosion of Chernobyl‘s No. 4 reactor spread 6.7 tons of
radioactive material across more than 77,000 square miles of Europe. It has been well
documented that three workers died from the explosion, 28 succumbed to acute radiation
poisoning over the next four months, and 19 others died of other causes in the quarter
century since the accident. In addition, thousands of children who drank radioactive milk
were subsequently diagnosed with thyroid cancer, including 15 who died of the disease.
But the extent of other long-term health problems suffered by those exposed to radiation
from the accident – including roughly 3,500 people who still work at the site – are largely
unknown. That‘s because money isn‘t available to study these people the way Japanese
A-bomb survivors have been tracked since 1945 by the Radiation Effects Research
Foundation, according to an article published online this week by Nature. For instance, the
National Cancer Institute – part of the U.S. National Institutes of Health – has been
following a cohort of 25,000 people who were children in the Ukraine and Belarus at the
time of the Chernobyl accident. That effort has revealed that those who got more radiation
and those who were deficient in iodine had a higher risk of thyroid cancer, but the ongoing
monitoring ended in 2008 due to a lack of funds, Nature reports. The European
Commission has been funding a group of scientists to develop a wish list of
Chernobyl-related studies. Suggestions include studying the 500,000 or so ―liquidators‖
who did clean-up and monitoring work around the nuclear plant soon after the accident.
The radiation exposure among this group varies widely, so a study would have the
potential to map out how health risks like cataracts and leukaemia are linked with specific
doses of radiation. In addition, it would be useful to track the children of these liquidators.
But that these and other studies would cost upwards of $4 million, and it‘s not at all clear
where those funds would come from. Without hard data on health risks, many exposed
people have simply assumed the worst, according to Nature. ―Some think they are
doomed because of their radiation exposure,‖ a Spanish radiation epidemiologist is quoted
as saying. One consequence is high rates of smoking and alcohol abuse that have actually
caused more health problems than the radiation itself. Some researchers are optimistic
that the problems in Fukushima will prompt governments to pony up the funds needed to
carry out these and other studies.
LA Times, 29 March 2011 http://www.latimes.com

Nanoparticles Shorten Roundworms’ Lives
Even though nanoparticles are increasingly entering the environment, scientists still have a
lot to learn about their biological effects. Now a new study by Chinese researchers has
discovered that exposure to cerium dioxide nanoparticles shortens the lifespan of the
roundworm Caenorhabditis elegans. Zhiyong Zhang and colleagues from the Chinese
Academy of Sciences‘ Institute of High Energy Physics exposed larvae of the widely used
model organism C. elegans to 8.5-nanometer particles of CeO2. Nanoparticles of CeO2
have many high-tech uses, such as in catalytic converters and as polish for silicon wafers.
They are also under consideration for use in eye drops and sunscreen. Research on other
nanoparticles has suggested that they can trigger oxidative stress in C. elegans. But
studies on CeO2 nanoparticles have hinted that they may actually protect against
cardiovascular, neurological, and radiological damage in rats, mice, and human cells in
vitro, respectively. However, those studies used high concentrations of the nanoparticles.
Zhang wanted to see how environmentally relevant concentrations of CeO2 nanoparticles
might affect an organism‘s health. The researchers raised C. elegans larvae on mats of
bacteria doped with CeO2 nanoparticles at concentrations ranging from 1 to 100 nM. They
then counted the surviving worms each day. At the lowest concentration of 1 nM, the mean
lifespan of the worms was 15 days. At the highest concentration of 100 nM, the worms
lived 14 days. Compared to control worms‘ lifespan of nearly 18 days, the lifespan of
worms exposed to nanoparticles decreased by 12% when averaged over all
concentrations. The researchers think the shortened lifespan is related to oxidative stress.
―We never expected to find any negative effects at such a low concentration,‖ Zhang says.
This is the first study, he says, indicating adverse effects of nanoparticles in the 1- to
100-nM range.
Chemical & Engineering News, 31 March 2011 http://pubs.acs.org/cen/news

Lawyers say plant leaked toxic chemical for years
Cancer-causing chemicals leaked from a Central California manufacturing plant owned by
a former subsidiary of drugmaker Merck & Co. and contaminated the surrounding
groundwater, air and soil for decades, lawyers for nearby residents told jurors in closing
arguments of their lawsuit against several companies. Attorney Mick Marderosian, who
represents 2,000 plaintiffs, said plant operators failed to alert a Merced housing community
directly across the street about contamination from hexavalent chromium, the chemical
made famous in the film ―Erin Brockovich.‖ The now-shuttered Baltimore Aircoil plant,
which manufactured cooling towers, used the chemicals to pressure-treat wood from 1969
to 1991. The plant was shut down in 1994. ―There was massive release of chemicals.
They migrated, entered the air and water in areas where people would have been
exposed,‖ Marderosian told jurors in U.S. District Court in Fresno. ―People were subject to
contamination without their knowledge.‖ The first phase of the trial focuses on whether
contamination did leak from the plant. If jurors find that to be true, the trial‘s second phase
would address whether residents were harmed by the chemical exposure. Merck, which
used to own Baltimore Aircoil, is leading remediation efforts at the plant. Company officials
acknowledged that hexavalent chromium contamination occurred but denied that any of it
left the confines of the plant at levels that could have harmed the health of residents. ―Did
contamination migrate to a location where it could impact residents? The answer is no,‖
said Merck attorney John Barg. State regulators testified during the trial that they see no
current evidence of contamination outside the plant site or evidence of contaminated
drinking water. Marderosian said a contamination plume in the groundwater polluted the
primary well supplying domestic water to Merced‘s Beachwood subdivision, located about
1,600 feet from the site. Merck sold Baltimore Aircoil in 1985 to Amsted Industries Inc.,
which is also a named defendant. Because plant records no longer exist, it‘s not known
how much hexavalent chromium could have leaked into the environment. Marderosian told
jurors the plant continued pressure-treating wood with dangerous chemicals even when
officials became aware of contamination. Merck first found hexavalent chromium in 1984
and was issued a violation in 1987. But according to documents, the company did not start
remediation until 1991, when a Merck consultant excavated contaminated soil from the
pond and disposed of it at a landfill in Kettleman City. Furthermore, hexavalent chromium
was released off-site through storm water discharges, Marderosian said. A year later, court
documents show, Merck became aware that the contamination plume in the groundwater
had migrated off the plant site. A groundwater sample taken at a mini-market about 300
feet from the site showed levels of hexavalent chromium at eight times the drinking water
standard, the documents state. In response, a Merck consultant installed a pump-and-treat
groundwater system in 1994 to control migration of contaminants and to remove
hexavalent chromium and arsenic from groundwater. Consultants also excavated the soil
from the area, covered it with an asphalt cap and installed a network of groundwater
monitoring wells. Marderosian argued that was not sufficient, noting that monitoring wells
were too shallow and there weren‘t enough of them. In 2006, court documents show,
Merck‘s own remediator concluded the company did not aggressively manage the site.
Since then, Barg said, Merck has continued the clean-up.
The Press Enterprise, 31 March 2011 http://www.pe.com/ap_news

Musseling Out Algae
Anglers are pulling up fewer and smaller fish from the Great Lakes than they did a decade
ago. A new study has now found that algal growth has dropped dramatically in the open
water of Lakes Michigan and Huron. The research suggests that invasive mussels are
depleting the base of the lakes‘ food chain by consuming most of the algae. The
researchers say that as a result, strategies for maintaining the lakes urgently need revision.
Scientists estimate that since the mid-1990s the lakes‘ biomass of fish has dropped by
about 95%, says Mary Anne Evans, an ecosystem ecologist at the University of Michigan,
Ann Arbor. Scientists have linked that decline to a 99% loss of the tiny shrimp-like
invertebrates that fish thrive on. These invertebrates in turn feed on algae, she explains. In
a previous study, it was found that invasive mussels reduced algal growth in the southern
basin of Lake Michigan, Evans says. ―We used the relationship between changes in silica
concentration and algal productivity to show that the same thing was happening across all
of the offshore waters of Lakes Michigan and Huron,‖ she says. Algal productivity in the
Great Lakes, the fixation of atmospheric carbon by algae, is largely a result of the size of
the springtime bloom of diatoms. Diatoms are algae that pull silica out of the water column
to encase themselves in intricate glass coatings, Evans explains. ―The amount of silica
removed by the bloom has long been used as an indicator of algal production in the Great
Lakes,‖ she says. Mining data on silica concentrations collected over the past 30 years,
Evans and her colleagues determined that algal production was about 80% lower in 2008
than in the 1980s and 1990s. The decline began in the mid-1990s after zebra and quagga
mussels invaded the lakes. The study estimates that mussels consume up to 74% of new
spring algae. When the foundation of a food web is depleted, Evans says, populations of
the fish at the top of the web can suffer. However, Bill Taylor, a limnologist at the
University of Waterloo thinks that ―the mussels are altering lake productivity not only by
filtering algae, but also by changing the way nutrients are distributed in the lake.‖ While the
offshore parts of the lakes are losing their algae, the nearshore areas are plagued with
nuisance algal blooms fed by high levels of phosphorus. Some studies suggest the
mussels may have concentrated phosphorus in the nearshore, thereby depriving the
offshore of an element critical to algal growth, he says. Nevertheless, Taylor and Evans
agree that the binational agreements capping phosphorus inputs to the lakes, which
haven‘t been changed since 1978, now ought to be reviewed more frequently. In addition,
Evans says, managers must boost monitoring of nearshore areas and manipulate nutrient
inputs for individual bays and basins in the lakes instead of applying a single target to an
entire lake. The study‘s publication is timely: Renegotiation of the U.S. and Canadian
Great Lakes Water Quality Agreement got under way last year.
Chemical & Engineering News, 30 March 2011 http://pubs.acs.org/cen/news

Antioxidant Formula Prior to Radiation Exposure May Prevent DNA Injury, Trial
A unique formulation of antioxidants taken orally before imaging with ionising radiation
minimises cell damage, researchers revealed at the Society of Interventional Radiology‘s
36th Annual Scientific Meeting in Chicago, Ill. In what the researchers say is the first
clinical trial of its kind, as much as a 50 percent reduction in DNA injury was observed after
administering the formula prior to CT scans. ―In our initial small study, we found that
pre-administering to patients a proprietary antioxidant formulation resulted in a notable
dose-dependent reduction in DNA injury,‖ said Kieran J. Murphy, M.D., FSIR, professor
and vice chair, director of research and deputy chief of radiology at the University of
Toronto and University Health Network, Toronto, Ontario, Canada. ―This could play an
important role in protecting adults and children who require imaging or a screening study,‖
he added. ―Pre-administering this formula before a medical imaging exam may be one of
the most important tools to provide radioprotection and especially important for patients in
the getting CT scans,‖ said Murphy. The findings from the study support the theory about a
protective effect during these kinds of exposure, he explained. ―There is currently a great
deal of controversy in determining the cancer risks associated with medical imaging exams.
Although imaging techniques, such as CT scans and mammograms, provide crucial and
often life-saving information to doctors and patients, they work by irradiating people with
X-rays, and there is some evidence that these can, in the long run, cause cancer,‖
explained Murphy. The interventional radiologist researchers responded to this patient
need by exploring a way to protect individuals from these potentially harmful effects. This
may be of importance to interventional and diagnostic radiologists and X-ray technologists
who have occupational exposure also. The small study demonstrated that even though
many antioxidants are poorly absorbed by the body, one particular mixture was effective in
protecting against the specific type of injury caused by medical imaging exams. People are
70 percent water, and X-rays collide with water molecules to produce free radicals (groups
of atoms with an unpaired number of electrons that are dangerous when they react with
cellular components, causing damage and even cell death) that can go on to do damage
by direct ionisation of DNA and other cellular targets, noted Murphy. The research team
evaluated whether a special combination of antioxidants have an ability to neutralize these
free radicals before they can do damage. ―Our intent was to develop an effective
proprietary formula of antioxidants to be taken orally prior to exposure that can protect a
patient‘s DNA against free radical mediated radiastion injury, and we have applied to
patent this formulation and a specific dose strategy,‖ said Murphy. During the study, the
researchers measured DNA damage as a surrogate marker for DNA injury. Blood was
drawn from two study volunteers in duplicate, creating four individual tests per data point.
DNA strand breaks are repaired by a big protein complex that binds to the site of the
damage. The researchers labelled one of the proteins with a fluorescent tag. Then, under
a powerful 3-D microscope, the DNA is examined for signs of repair. The more repair that
is seen, the more DNA damage must have been done by the CT scan to initiate that repair.
The experiments clearly showed a reduction of DNA repair in the treatment group, which
means that there was less DNA injury as a result of pre-administering the antioxidant
mixture, said Murphy. The researchers concede that this is a small study and that a lot
more research needs to be done; however, these initial results point toward a positive
future for this kind of treatment. The group says the next step is a clinical trial in Toronto.
Science Daily, 29 March 2011 http://www.sciencedaily.com

Evidence ties smoking to throat, stomach cancer
Smokers face an increased risk of certain types of throat and stomach cancers, even
years after they quit, a new study has discovered. Combining the results of 33 past studies,
Italian researchers found that current smokers were more than twice as likely as
nonsmokers to develop cancer, either in their oesophagus or in a part of the stomach
called the gastric cardia. In some of the studies, the risk of oesophagus cancer remained
high even when people had quit smoking three decades earlier. The two cancers, both
known as adenocarcinomas, are relatively uncommon in Western countries. Rates
elsewhere are much higher, especially in less developed countries. However, in recent
decades, rates of the cancers have been rising in the U.S. and Europe -- possibly related
to growing rates of obesity. Smoking has long been considered a risk factor for the two
cancers. But these latest findings offer a ―better quantification‖ of the risks, said senior
researcher Dr. Eva Negri, of the ―Mario Negri‖ Institute of Pharmacological Research in
Milan. What‘s more, they suggest that the risks remain higher than average for some time
after smokers quit. ―Stopping smoking is highly beneficial at any age, but it appears that for
these cancers the risk decreases only slowly,‖ Negri said. During the new study, published
recently in the journal Epidemiology, Negri and her colleagues pooled the results of 33
previous studies. In most of them, researchers had compared a relatively small group of
patients with either oesophagus or gastric cardia tumours against a cancer-free group. In
three studies, researchers had followed large groups of adults over time, charting any new
cases of oesophageal or gastric cardia cancers.
Overall, Negri‘s team found, current smokers had more than double the odds of
developing either of the cancers, compared to people who had never smoked. In addition,
while that risk declined after people stopped smoking; it was still 62 percent higher in
former smokers than in lifelong non-smokers. In some studies, the extra risk of
oesophagus cancer persisted up to 30 years after people had quit. Since both
oesophageal and gastric cardia adenocarcinomas are fairly uncommon in the West, the
absolute risks to any one smoker may be low. According to the American Cancer Society,
the average American has a one in 200 chance of developing any type of oesophageal
cancer over a lifetime, and a one in 114 risk of developing some form of stomach cancer.
By comparison, the odds of developing lung cancer are about one in 13 for men, and one
in 16 for women -- counting both smokers and non-smokers. Smokers would be at much
greater risk than lifelong non-smokers. Lung cancer, heart disease and other ills are
―numerically more important‖ than oesophageal and gastric cardia cancers when it comes
to the health consequences of smoking, Negri noted. The types of studies that were
available for her team to analyse can‘t prove that smoking causes adenocarcinoma of the
oesophagus or gastric cardia. To do that, researchers would have to purposely expose
some people to years of tobacco smoke and see what happens to them over time - and
ethical reasons make a study like that impossible. Still, Negri and her colleagues say, the
risks seen in the current study offer smokers one more reason to quit -- and non-smokers
one more reason to never start.
Reuters Health, 29 March 2011 http://www.reuters.com/news/health

Common Yellow Lab Dye Profoundly Extends Lifespan in Healthy Nematodes, and
Slows Alzheimer’s Disease-Like Pathology in Worms
Basic Yellow 1, a dye used in neuroscience laboratories around the world to detect
damaged protein in Alzheimer‘s disease, is a wonder drug for nematode worms. In a new
study, published in the journal Nature, the dye, also known as Thioflavin T (ThT), extended
lifespan in healthy nematode worms by more than 50 percent and slowed the disease
process in worms bred to mimic aspects of Alzheimer‘s. The research, conducted at the
Buck Institute for Research on Aging, could open new ways to intervene in aging and
age-related disease. The study highlights a process called protein homeostasis -- the
ability of an organism to maintain the proper structure and balance of its proteins, which
are the building blocks of life. Genetic studies have long indicated that protein homeostasis
is a major contributor to longevity in complex animals. Many degenerative diseases have
been linked to a breakdown in the process. Buck faculty member Gordon Lithgow, PhD,
who led the research, said this study points to the use of compounds to support protein
homeostasis, something that ThT, did as the worms aged. ThT works as a marker of
neurodegenerative diseases because it binds amyloid plaques -- the toxic aggregated
protein fragments associated with Alzheimer‘s. In the nematodes ThT‘s ability to not only
bind, but also slow the clumping of toxic protein fragments, may be key to the compound‘s
ability to extend lifespan, according to Lithgow. ―We have been looking for compounds that
slow aging for more than ten years and ThT is the best we have seen so far,‖ said Lithgow.
―But more exciting is the discovery that ThT so dramatically improves nematode models of
disease-related pathology as well,‖ said Lithgow, who said the discovery brings together
three crucial concepts in the search for compounds that could extend healthspan, the
healthy years of life. ―ThT allows us to manipulate the aging process, it has the potential to
be active in multiple disease states and it enhances the animal‘s innate ability to deal with
changes in its proteins.‖ The research was the brainchild of Silvestre Alavez, PhD, a staff
scientist in the Lithgow lab. Alavez was trained in neuroscience and knew about the use of
these compounds to detect disease-related proteins. With the idea that small molecules
could impact protein aggregation, he looked at 10 compounds and found five that were
effective in increasing lifespan in the worms. Alavez said curcumin, the active ingredient in
the popular Indian spice turmeric, also had a significant positive impact on both healthy
worms and those bred to express a gene associated with Alzheimer‘s. ―People have been
making claims about the health benefits of curcumin for many years. Maybe slowing aging
is part of its mechanism of action,‖ said Alavez. Curcumin is currently being tested in
several human clinical trials for conditions ranging from colon cancer to rheumatoid
arthritis to depression. Alavez says the study supports the concept that protein
homeostasis should be the focus of future research. ―We now have an exciting new
avenue in the search for compounds that both extend lifespan and slow disease
processes,‖ said Alavez. ―Any small molecule that maintains protein homeostasis during
aging could be active against multiple disease states.‖ Follow up research on ThT is now
underway in mice bred to have Alzheimer‘s.
Science Daily, 30 March 2011 http://www.sciencedaily.com

Walnuts Are Top Nut for Heart-Healthy Antioxidants
A new study has found that walnuts are number one among a family of foods that lay claim
to being among Mother Nature‘s most nearly perfect packaged foods: Tree and ground
nuts. In a report given in Anaheim, California at the 241st National Meeting & Exposition of
the American Chemical Society on 27 March, scientists presented an analysis showing
that walnuts have a combination of more healthful antioxidants and higher quality
antioxidants than any other nut. ―Walnuts rank above peanuts, almonds, pecans,
pistachios and other nuts,‖ said Joe Vinson, Ph.D., who did the analysis. ―A handful of
walnuts contain almost twice as much antioxidants as an equivalent amount of any other
commonly consumed nut. But unfortunately, people don‘t eat a lot of them. This study
suggests that consumers should eat more walnuts as part of a healthy diet.‖ Vinson noted
that nuts in general have an unusual combination of nutritional benefits -- in addition those
antioxidants -- wrapped into a convenient and inexpensive package. Nuts, for instance,
contain plenty of high-quality protein that can substitute for meat; vitamins and minerals;
dietary fibre; and are dairy- and gluten-free. Years of research by scientists around the
world link regular consumption of small amounts of nuts or peanut butter with decreased
risk of heart disease, certain kinds of cancer, gallstones, Type 2 diabetes, and other health
problems. Despite all the previous research, until now scientists had not compared both
the amount and quality of antioxidants found in different nuts, Vinson said. He filled that
knowledge gap by analysing antioxidants in nine different types of nuts: walnuts, almonds,
peanuts, pistachios, hazelnuts, Brazil nuts, cashews, macadamias, and pecans. Walnuts
had the highest levels of antioxidants. In addition, Vinson discovered that the quality, or
potency, of antioxidants present in walnuts was highest among the nuts. Antioxidants in
walnuts were 2-15 times as potent as vitamin E, renowned for its powerful antioxidant
effects that protect the body against damaging natural chemicals involved in causing
disease. ―There‘s another advantage in choosing walnuts as a source of antioxidants,‖
said Vinson, who is with the University of Scranton in Pennsylvania. ―The heat from
roasting nuts generally reduces the quality of the antioxidants. People usually eat walnuts
raw or unroasted, and get the full effectiveness of those antioxidants.‖ If nuts are so
healthful and nutritious, why don‘t people eat more? Vinson‘s research shows, for instance,
that nuts account for barely 8 percent of the daily antioxidants in the average person‘s diet.
Many people, he said, may not be aware that nuts are such a healthful food. Others may
be concerned about gaining weight from a food so high in fat and calories. But he points
out that nuts contain healthful polyunsaturated and monosaturated fats rather than
artery-clogging saturated fat. As for the calories, eating nuts does not appear to cause
weight gain and even makes people feel full and less likely to overeat. In a 2009 U. S.
study, nut consumption was associated with a significantly lower risk of weight gain and
obesity. Still, consumers should keep the portion size small. Vinson said it takes only
about 7 walnuts a day, for instance, to get the potential health benefits uncovered in
previous studies.
Science Daily, 28 March 2011 http://www.sciencedaily.com

Japan radiation in U.S., not health concern: EPA
U.S. government sensors are detecting traces of radiation believed to be from Japan‘s
stricken nuclear plant, but they remain far below levels considered dangerous to people,
the Environmental Protection Agency said recently. The EPA said 12 air monitoring
locations across the country have identified trace amounts of radioactive isotopes believed
to have come from Japan‘s crippled Fukushima nuclear plant hit by an earthquake and
tsunami on 11 March. Some of the readings were slightly higher than similar ones picked
up last week, but were still tiny compared with radiation coming from natural sources, the
EPA said. ―These types of findings are to be expected in the coming days and are still far
below levels of public health concern,‖ the EPA said in a release. Radiation at the
Fukushima plant poses a threat to workers, but Japanese officials and international
experts have said radiation levels away from the plant are not dangerous to people, who in
any case face higher doses from sources like X-rays and flying. The EPA has more than
100 fixed monitors that measure air radiation levels in 48 states. It deployed additional air
monitors to Hawaii, Alaska, Guam, and the Northern Mariana Islands after the disaster in
Japan. Recently, the EPA said ―minuscule‖ amounts of radiation consistent with a release
from the damaged Fukushima plant were detected in Sacramento, California. But those
were lower than levels that people get from various sources including natural radiation
from certain rocks. Low levels of radioactive iodine-131 believed to be from the Fukushima
plant have also been detected by nuclear power stations in North Carolina and Florida.
Monitors at Progress Energy‘s nuclear plants in South Carolina and Florida picked up low
levels of radioactive iodine-131. So did Duke Energy‘s monitors at its two nuclear facilities
in South Carolina and in North Carolina.
Reuters Health, 29 March 2011 http://www.reuters.com/news/health

Nanoscale determination of ecotoxicological hallmark in animal hair
After Stockholm Convention Bio-monitoring studies for estimation population health
surveillance and exposure risk assessment of different chemical contaminants, such as
chlorinated compounds or polycyclic aromatic hydrocarbon (PAH) had become an
important task. Earlier the toxicological evaluation of humans was done using invasive
methods such as surgery or pricking. Today many scientists tried to elaborate
non-invasive analytical methods without disparage the final results. Last year studies have
shown that a relative higher pollution with organochlorine and polycyclic aromatic
hydrocarbon compounds in surrounding regions of Dej, Transylvania. The pollution with
chlorinated compounds as chlorinated solvents was attributed to the industrial activities
from this region. The levels in soil and river water of these compounds were ~20 - 60
µg•kg-1 and ~15 - 45 µg•L-1, respectively where as for PAHs soil and river water levels
were; for two ring species was between ~26 - 35 µg•kg-1 and ~21 - 30 µg•L-1,
respectively; for three ring species was 15 - 35 µg•kg-1 and ~10 - 24 µg•L-1
respectively; and in case of four ring species was between 10 - 20 µg•kg-1 and ~ 3 - 15
µg•L-1 respectively. These results carried on concern regarding the bioaccumulation of
these pollutants by humans through food web chain. In order to establish the uptake level
of these compounds by humans, home grown animal‘s such as pig and cow hair were
analysed through SIM-GC-MS mode and ECD-FID-GC. The presence of chlorinated
solvents detected in pig and cows hair. Difference between accumulation levels of PAH
metabolites were also observed between cow and pig hair samples.
Authors: Kovacs, Melinda Haydee; Ristoiu, Dumitru;Ristoiu, Tania
Full Source: Proceedings of SPIE 2010, 7821, 782121-782121-6 (English)

Accumulation and elimination characteristics of heavy metal cadmium in Bullacta
exarata from intertidal zone of Tianjin, China
Cadmium accumulation and elimination have important influence on bioremediation,
pollutant eco-toxicity and environmental risk assessment. The characteristics of cadmium
accumulation and elimination in Bullacta exarata‘s body and liver, which were from the
intertidal zone of Tianjin, were studied. The entire experiment included two parts,
accumulation and elimination. The samples were frozen, dried, ground, blended and
weighed, followed by measuring using Atomic Absorption Spectrometry (AAS). The
accumulation period was 14 days. The mass fractions of cadmium in body and liver were
from high to low, and the maximum was at 7 days. The accumulation in liver was greater
than that in the body, and, the depuration period was 12 days while the stable point was at
9 days. The accumulation of cadmium in Bullacta exarata related not only with their life
behaviour but also with their habitats. In the natural environment, the human input of
cadmium should be strictly controlled, particularly the discharge of the cadmium industrial
waste water.
Authors: Chen, Nan; Liu, Xianbin; Tian, Shengyan; Liu, Zhanguang; Sun, Lianna; Li,
Full Source: Nongye Huanjing Kexue Xuebao 2010, 29(9), 1687-1692 (Chinese)

Analysis of the CYP1A1 mRNA Dose-Response in Human Keratinocytes Indicates
that Relative Potencies of Dioxins, Furans, and PCBs Are Species and Congener
Toxic equivalency factors (TEFs) primarily based on rodent data do not accurately predict
in vitro human responsiveness to certain dioxin-like chemicals (DLCs). To investigate this
in cells responsive to dioxins and relevant to chloracne, normal human epidermal
keratinocytes were treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and several
DLCs, each with a TEF value of 0.1, representing 3 classes of congeners. The authors
estimated half maximal effective concentration(EC50)-based donor-specific relative
potency (REP) values for cytochrome P 450 1A1 (CYP1A1) mRNA induction for TCDD,
1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (HxCDD), 2,3,7,8-tetrachlorodibenzofuran
(TCDF),1,2,3,6,7,8-hexachlorodibenzofuran (HxCDF), and 3,3‘,4,4‘,5-pentachlorobiphenyl
(PCB 126). They also detected EC50-based population-level REP values (n=4) for
CYP1A1 mRNA induction for TCDD, HxCDF, and PCB 126. Moreover an alternative factor,
the relative threshold factor (RTF) based on the low end (threshold) of the dose-response
curve, was calculated. The results demonstrated that HxCDF had a population-based REP
value of 0.98, 9.8-fold higher than its assigned TEF value of 0.1. Conversely, PCB 126 had
an REP value of 0.0027 and an RTF of 0.0022, 37-fold and 45-fold less than its assigned
TEF of 0.1, respectively. The REP values for HxCDD and TCDF were 0.24 and 0.10,
respectively, similar to their assigned value of 0.1. Therefore, although the DLCs tested in
the current study all possessed the same assigned TEF value of 0.1, congener-specific
differences in REPs and RTFs were observed for human keratinocytes. These
congener-specific discrepancies are likely because of differences in interspecies factors
that have yet to be defined.
Authors: Sutter, Carrie H.; Bodreddigari, Sridevi; Sutter, Thomas R.; Carlson, Erik A.;
Silkworth, Jay B.
Full Source: Toxicological Sciences 2010, 118(2), 704-715 (English)

PCB-47, PBDE-47, and 6-OH-PBDE-47 Differentially Modulate Human GABAA and
α4β2 Nicotinic Acetylcholine Receptors
Polychlorinated biphenyls (PCBs) and the structurally related polybrominated diPhenyl
ethers (PBDEs) are abundant persistent organic pollutants that exert several comparable
neurotoxic effects. Also hydroxylated metabolites of PCBs and PBDEs have an increased
neurotoxic potency. The authors demonstrated that PCBs can act as (partial) agonist on
GABAA neurotransmitter receptors, with PCB-47 being the most potent congener.
However, it is unknown whether PBDE-47 and its metabolite 6-OH-PBDE-47 exert similar
effects and if these effects are limited to GABAA receptors only. Therefore in this study
authors investigated the effects of PCB-47, PBDE-47, and 6-OH-PBDE-47 on the
inhibitory GABAA and excitatory α4β2 nicotinic acetylcholine (nACh) receptor expressed in
Xenopus oocytes using the two-electrode voltage-clamp technique. Since human
exposure is generally not limited to individual compounds, experiments with binary
mixtures were also performed. PCB-47 and 6-OH-PBDE-47 act as full and partial agonist
on the GABAA receptor. However, both congeners act as antagonist on the nACh receptor.
PBDE-47 did not affect either type of receptor. Binary mixtures of PCB-47 and
6-OH-PBDE-47 induced an additive activation as well as potentiation of GABAA receptors
whereas this mixture resulted in an additive inhibition of nACh receptors. Binary mixtures
of PBDE-47 and 6-OH-PBDE-47 yielded similar effects as 6-OH-PBDE-47 alone. The
results demonstrated that GABAA and nACh receptors are affected differently by PCB-47
and 6-OH PBDE-47, with inhibitory GABAA-mediated signalling potentiated and excitatory
α4β2 nACh-mediated signalling inhibited. The authors concluded that considering these
opposite actions and the additive interaction of the congeners, these effects are likely to be
augmented in vivo.
Authors: Hendriks, Hester S.; Fernandes, Elsa C. Antunes; Bergman, Aake; van den Berg,
Martin; Westerink, Remco H.S.
Full Source: Toxicological Sciences 2010, 118(2), 635-642(English)

The use of In Vitro Toxicity Data and Physiologically Based Kinetic Modelling to
Predict Dose-Response Curves for In Vivo Developmental Toxicity of Glycol Ethers
in Rat and Man
Regulatory assessment of systemic toxicity is almost solely carried out using animal
models. The European Commission‘s REACH legislation stimulates the use of animal-free
approaches to obtain information on the toxicity of chemicals. In vitro toxicity tests provide
in vitro concentration-response curves for specific target cells, whereas in vivo
dose-response curves are regularly used for human risk assessment. This study showed
an approach to predict in vivo dose-response curves for developmental toxicity by
combining in vitro toxicity data and in silico kinetic modelling. A physiologically based
kinetic (PBK) model was developed, describing the kinetics of 4 glycol ethers and their
embryotoxic alkoxyacetic acid metabolites in rat and man. In vitro toxicity data of these
metabolites derived in the embryonic stem cell test were used as input in the PBK model
to extrapolate in vitro concentration-response curves to predicted in vivo dose-response
curves for developmental toxicity of the parent glycol ethers in rat and man. The predicted
dose-response curves for rat were found to be in order with the embryotoxic dose levels
measured in reported in vivo rat studies and therefore, predicted dose-response curves for
rat could be used to set a point of departure for deriving safe exposure limits in human risk
assessment. In vitro toxicity data and human PBK model data combination allowed the
prediction of dose-response curves for human developmental toxicity. The authors
concluded that the approach could therefore provide a means to reduce the need for
animal testing in human risk assessment practices.
Authors: Louisse, Jochem; de Jong, Esther; van de Sandt, Johannes J. M.; Blaauboer,
Bas J.; Woutersen, Ruud A.; Piersma, Aldert H.; Rietjens, Ivonne M. C. M.; Verwei, Miriam
Full Source: Toxicological Sciences 2010, 118(2), 470-484 (English)
Metal ions in human cancer development
The use of metals is key to human civilisation, and has been in the environment during the
entire evolution of man. None-the-less, several very toxic species are included in the
metallic elements and compounds either widely used by man and/or found in the human
environment which includes arsenic and arsenic compounds, beryllium and beryllium
compounds, cadmium and cadmium compounds, chromium (VI) compounds, and nickel
compounds. These five metallic agents considered human carcinogens and all of which
are proven carcinogens in laboratory animals as well. There is significant human exposure
to these carcinogenic inorganic, either occupationally, through the environment, or both. In
the workplace, inhalation is typical while inhalation or ingestion occurs from environmental
sources. These metallic carcinogens frequently cause tumours at the portal of entry. Also,
agent-specific tumours like urinary bladder tumours after arsenic exposure, is due to
bio-kinetics or mechanisms that are specific to arsenic could occur. Even in their simplest
elemental form, metals are not inert, and have biological activity. However, these inorganic
carcinogens, when in the atomic form, cannot be broken down into less toxic subunits, and
is why they are so important as environmental human carcinogens.
Authors: Tokar, Erik J; Benbrahim-Tallaa, Lamia; Waalkes, Michael P.
Full Source: Metal Ions in Life Sciences 2011, 8(Metal Ions in Toxicology), 375-401

Metal ions affecting the pulmonary and cardiovascular systems
Metals, such as copper and manganese, are essential to life and play irreplaceable roles
in functioning of important enzyme systems however, other metals are xenobiotics, which
they have no useful role in human physiology and, even worse, as in the case of lead, may
be toxic even at trace levels of exposure. Even with the essential metals there is a
potential to turn harmful at very high levels of exposure. Toxic metal exposure may lead to
serious risks to human health. Due to extensive use of toxic metals and their compounds
in industry and consumer products, these agents have been widely disseminated in the
environment. Metals are not biodegradable, therefore they can persist in the environment
and produce a variety of adverse effects such as exposure to metals can lead to damage
in a variety of organ systems and, in some cases, metals also have the potential to be
carcinogenic. Even though the importance of metals as environmental health hazards is
now widely appreciated, the specific mechanisms by which metals produce their adverse
effects have not yet been fully elucidated. The unifying factor in determining toxicity and
carcinogenicity for most metals is the generation of reactive oxygen and nitrogen species.
Metal-mediated formation of free radicals causes various modifications to nucleic acids,
enhanced lipid peroxidation, and altered calcium and sulfhydryl homeostasis. While copper,
chromium, and cobalt undergo redox-cycling reactions, for metals cadmium and nickel the
primary route for their toxicity is depletion of glutathione and bonding to sulfhydryl groups
of proteins. The authors concluded that the toxic effects of different metallic compounds
may be manifested in the pulmonary and cardiovascular systems. The knowledge of
health effects due to metal exposure is necessary for practising physicians, and should be
assessed by inquiring about present and past occupational history and environmental
Authors: Corradi, Massimo; Mutti, Antonio
Full Source: Metal Ions in Life Sciences 2011,8(Metal Ions in Toxicology), 81-105 (English)

Analysis of serum lipid peroxidation of coke oven workers
This study investigated the serum levels of malondialdehyde and hydrogen peroxide and
activities of superoxide dismutase and glutathione peroxidase in workers exposed to coke
oven emission. The authors detected the serum levels of malondialdehyde and hydrogen
peroxide and activities of superoxide dismutase and glutathione peroxidase of 152 coke
oven workers and 125 controls with the test kits. The serum levels of malondialdehyde and
hydrogen peroxide in the exposure group were higher than those in the control group. The
serum activities of superoxide dismutase and glutathione peroxidase in the exposure
group were lower than those in the control group. Exposed group was stratified according
to job categories. The serum levels of malondialdehyde and hydrogen peroxide in the oven
top workers were higher than those of the oven side workers. While the serum activities of
superoxide dismutase and glutathione peroxidase in the oven top workers were lower than
those of the oven side workers. All the differences were statistically significant (P<0.05).
Coke oven emission could result in lipid peroxidation damage of the exposed workers. The
authors concluded that serum malondialdehyde, hydrogen peroxide, superoxide dismutase
and glutathione peroxidase might be used as the indicators in health surveillance of the
occupational hazard of the coke oven workers.
Authors: Zhu, Han-song; Zhao, Yong; Wang, Li-Xia; Feng, Fei-Fei; Wang, Shi-Bin; Li,
Zhi-Tao; Wu, Yi-Ming
Full Source: Gongye Weisheng Yu Zhiyebing 2010, 36(2), 65-69 (Ch)

Occupational and environmental mercury exposure among small-scale gold miners
in the Talensi-Nabdam District of Ghana’s Upper East region
Mercury (Hg) use in small-scale gold (Au) mining is ubiquitous across Ghana, but little is
known about the extent to which such activities have contaminated community residents
and miners. Occupational exposure to elemental Hg (detected by urine sampling) and
dietary exposure to methylmercury (detected by hair sampling) were assessed among 120
participants from a mining community in the Talensi-Nabdam District, Upper East Region
of Ghana in summer 2009. More than one-fifth of the participants had moderately high
urinary Hg concentrations (>10 íg/L); 5% had urine Hg concentrations, which exceeded
the World Health Organisation guideline value (50 íg/L).
When participants were stratified according to occupation, those active in the mining
industry had the highest Hg concentrations. Individuals who burned amalgam had urine Hg
concentrations (median: 43.8 íg/L; mean (standard deviation: 171.1 ( 296.5 íg/L; n ) 5)
significantly higher than median concentrations measured in mechanical operators (11.6
íg/L, n ) 4), concession managers/owners (5.6 íg/L, n ) 11), excavators who blast and
chisel ore (4.9 íg/L, n ) 33), individuals who sift and grind crushed ore (2.2 íg/L, n ) 47),
support workers (0.5 íg/L, n ) 14), and those with no role in the mining sector (2.5 íg/L, n )
6). There was a significant positive Spearman correlation between fish consumption and
hair Hg concentrations (r ) 0.30), but not with urine Hg (r ) 0.18); further studies are
needed to document which types of fish are consumed as well as portion sizes. The
authors concluded that as 200,000 people in Ghana are involved in the small-scale Au
mining industry and since the numbers are expected to grow in Ghana and many other
regions of the world, elucidating Hg exposure pathways in such communities is important
to help shape policies and behaviour which may minimise health risks.
Authors: Paruchuri, Yasaswi; Siuniak, Amanda; Johnson, Nicole; Levin, Elena; Mitchell,
Katherine; Goodrich, Jaclyn M.; Renne, Elisha P.; Basu, Niladri
Full Source: Science of the Total Environment 2010, 408(24), 6079-6085 (Eng)

Urinary Paranitrophenol, a Metabolite of Methyl Parathion, in Thai Farmer and Child
Human exposure to methyl parathion can be assessed by measuring the concentration of
its metabolite paranitrophenol (PNP) in urine. The authors conducted a biological
monitoring study in Chiang Mai, Thailand, which measured PNP and dialkylphosphate
metabolites (i.e., dimethylphosphate [DMP] and dimethylthiophosphate [DMTP]) of methyl
parathion in urine samples collected from 136 farmers (age 20 to 65 years) and 306 school
children (age 10 to 15 years) in 2006. Participants came from 2 topographically different
areas: One was colder and mountainous, whereas the other was alluvial with climate
fluctuations depending on the monsoon season. Both children and farmers were recruited
from each area. Despite methyl parathion‘s prohibited use in agriculture in 2004, the
authors detected PNP in >90% of all samples analysed. A nonparametric correlation test
(PNP vs. DMP and DMTP)was applied to determine whether the PNP found in most of the
samples tested resulted from exposures to methyl parathion. DMP (Spearman‘s rho )
0.601 [p ) 0.001] for farmers and Spearman‘s rho ) 0.263 [p < 0.001] for children) and
DMTP (Spearman‘s rho ) 0.296 [p ) 0.003] for farmers and Spearman‘s rho) 0.304 [p <
0.001] for children) were positively correlated with PNP, suggesting a common source for
the 3 analytes, presumably methyl parathion or related environmental degradates.
Although a modest correlation was detected between the metabolites, these findings
suggest that despite the prohibition, at least a portion (approximately 25% to 60%) of the
PNP detected among farmers and children in Thailand may be attributed to exposure from
continued methyl parathion use.
Authors: Panuwet, Parinya; Prapamontol, Tippawan; Chantara, Somporn;
Thavornyuthikarn, Prasak; Bravo, Roberto; Restrepo, Paula; Walker, Robert D.; Williams,
Bryan L.; Needham, Larry L.; Barr, Dana B.
Full Source: Archives of Environmental Contamination and Toxicology 2009, 57(3),
623-629 (Eng)

Determination of pseudocholinesterase serum activity among Agrinion pesticide
applicators pre- and post-exposed to organophosphates (fenthion and dimethoate)
Organophosphate (OP) pesticides are used in agriculture in order to raise crop production.
This study investigated the biological effects of two OPs, fenthion, and dimethoate, among
270 farm workers in the area of Agrinion (Western Greece) by measuring the serum
butyrylcholinesterase (BChE) activity during the years 2004-2006. The BChE activity was
photometrically analysed before and after exposing to OP. The results demonstrated that
the median BChE activity was reduced in the spraying period in comparison with the
non-spraying period (7604 versus 9557 units L-1). In addition, a significant difference was
detected in median pseudocholinesterase (PChE) activity between the two OPs (fenthion
applicators -26.87%, dimethoate applicators -15.95%). The authors also found that the
duration of OP spraying influenced the mean BChE activity, which was -9.83% after 1 day,
-23.81% after 2-3 days, and -25.26% after 4-7 days of spraying and there was also
reduced levels of the mean value of PChE activity observed in occupational applicators in
exposure periods (5446 units L-1), and in non-exposure periods (6950 units L-1), as well.
The extent of using protective equipment influenced the mean levels of BChE activity:
-23.9% without any protection, -15% with partial protection, and -7.4% in those applicators
with full protective equipment. The authors concluded that the mean value of serum BChE
activity was reduced after exposure to two Ops and this reduction depends on the
particular OP, the duration of the exposure, and use or not of personal protective
equipment by pesticide applicators.
Authors: Vrioni, Georgia; Souki, Helen; Katramadou, Myrto; Kasiotis, Konstantinos M.;
Carageorgiou, Haris
Full Source: Toxicological and Environmental Chemistry 2011, 93(1), 177-187 (Eng)
Exposure to textile chemicals leads to microcytic anaemia and hypersensitivity in
textile workers
This study investigated the toxic effects of dyeing chemicals on various haematological
parameters of textile workers. A total of 62 workers involved in dyeing processes were
compared with 95 control subjects. The findings revealed significant decrease in Hb
content, hematocrit, haematological indexes and neutrophil whereas leukocytes,
eosinophils and lymphocytes counts were observed to increase in the exposed workers.
The authors concluded that the haematological parameters are as useful as physiological
indexes for hazards caused by toxic chemicals used in the textile industry.
Authors: Liaqat, Iram; Arshad, Mohammad; Arshad, Raheela; Arshad, Najma
Full Source: Pakistan Journal of Zoology 2009, 41(5), 381-387 (Eng)

Analysis of acrylonitrile, 1,3-butadiene, and related compounds in
acrylonitrile-butadiene-styrene copolymers for kitchen utensils and children’s toys
by headspace gas chromatography/mass spectrometry
In this study, a headspace gas chromatography/mass spectrometry method was
developed for the simultaneous detection of the residual levels of acrylonitrile (AN),
1,3-butadiene (1,3-BD), and their related compounds containing propionitrile (PN) and
4-vinyl-1-cyclohexene (4-VC) in acrylonitrile- butadiene-styrene (ABS) copolymers for
kitchen utensils and children‘s toys. A sample was cut into small pieces, then
N,N-dimethylacetamide and an internal standard were added in a sealed headspace vial.
The vial was incubated for 1 h at 90° and the headspace gas was analysed by GC-MS.
The recovery rates of the analytes were 93.3-101.8% and the coefficients of variation were
0.3-6.5%. In ABS copolymers, the levels were 0.3-50.4 íg/g for AN, ND-4.5 íg/g for PN,
0.06-1.58 íg/g for 1,3-BD, and 1.1-295 íg/g for 4-VC. The highest level was found for 4-VC,
which is a dimer of 1,3-BD, and the next highest was for AN, which is one of the
monomers of the ABS copolymer. Furthermore, the method was also applied to
acrylonitrile-styrene (AS) copolymers and polystyrenes (PS) for kitchen utensils, and
nitrile-butadiene rubber (NBR) gloves. In AS copolymers, AN and PN were detected at
16.8-54.5 and 0.8-6.9 íg/g, respectively. On the other hand, the levels in PS and NBR
samples were all low.
Authors: Ohno, Hiroyuki; Kawamura, Yoko
Full Source: Journal of AOAC International 2010, 93(6), 1965-1971 (Eng)

Effects of road traffic scenarios on human exposure to air pollution
Human exposure to air pollution has been identified as a major problem due to its known
impact on human health. Particulate matter is a pollutant which raises special concern due
to the adverse health effects on sensitive groups of the population, such as asthmatic
children. This study is part of the SaudAr research project, which assessed the air quality
effects on the health of a population group risk (asthmatic school children) living in an
urban area (Viseu). The study investigated the influence of road traffic emissions on air
quality and consequently, on human exposure. For this purpose, the CFD model VADIS
integrating an exposure module has been applied over the town of Viseu, for the periods of
one week in winter and one week in summer, to four different situations: the reference
year (2006) and three future scenarios for the year 2030, BAU, Green and Gray scenario.
The differences among the scenarios include changes on the existing land use, the vehicle
fleet composition, the mobility, the vehicle technologies and the fuel types. Field
campaigns were performed in order to obtain information about vehicle fleet in the town of
Viseu and mobility patterns. The quantification of road traffic emissions and the hourly
traffic emissions patterns for all scenarios was carried out by the application of the TREM
model. The results revealed an increase in PM10 emissions, concentrations and exposure
in all future scenarios, particularly in winter with an increase around 80% in the BAU and
Gray scenarios and only 34% in the Green scenario.
Authors: Borrego, C.; Costa, A. M.; Tavares, R.; Lopes, M.; Valente, J.; Amorim, J. H.;
Miranda, A. I.; Ribeiro, I.; Sa, E.
Full Source: WIT Transactions on Ecology and the Environment 2009, 123(Air Pollution
XVII), 89-100 (Eng)

Airborne particulate matter and mechanisms of production of free radicals in the
human body
Fine- and coarse-grained airborne particulate matter (PM) has been linked to increases in
respiratory diseases and lung cancer. Due to their aerodynamic diameter (10 ím), these
particles are carried into the alveoli, where they remain for a long time and may cause
inflammatory response and lung epithelial injury. PM contains a variety of compounds,
such as heavy metals, polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs, quinones
and stable free radicals absorbed in a carbonaceous polymeric matrix. The results showed
that PM produce reactive oxygen species (ROS) especially the production of superoxide
anion (O2 ¥-2) and the damaging hydroxyl radical (OH¥), generated by particulate matter
(PM) in aqueous solutions, which at physical conditions may cause oxidative damage to
membrane lipids, enzymes and mitochondrial and nuclear DNA.
Authors: Fiotakis, K.; Vlahogianni, T.; Valavanidis, A.
Full Source: Chemika Chronika, Genike Ekdose 2009, 71(10), 14-19 (Greek)

Pollutant Concentrations within Households in Lao PDR and Association with
Housing Characteristics and Occupants’ Activities
In this study, the authors report the results of a 5-month (December 2005 to April 2006)
indoor air quality assessment measuring PM10, CO, and NO2 concentrations inside 167
residential dwellings in the Lao Peoples Democratic Republic (Lao PDR) as a function of
household characteristics and occupant activities. Extremely high PM10 and NO2
concentrations (12 h mean PM10 concentrations ) 1275 ( 98 and 1183 ( 99 íg/m3 in
Vientiane and Bolikhamxay provinces, respectively; 12 h mean NO2 concentrations) 1210
( 94 and 561 ( 45 íg/m3 in Vientiane and Bolikhamxay, respectively) were measured in the
dwellings. Correlations, univariate and multivariate analysis of variation, and linear
regression results suggested a substantial contribution from cooking and smoking. PM10
concentrations were significantly higher in houses without a chimney versus houses in
which cooking occurred on a chimney-equipped stove; however, no significant pollutant
concentration differences were observed as a function of cooking location. PM10 and NO2
concentrations were higher in houses in which smoking occurred, suggesting a
relationship between increased indoor pollutant concentrations and smoking (0.05 < p <
0.10). Soil floor dust resuspension was another significant PM10 source inside houses
(634 íg/m3, p <0.05).
Authors: Morawska, L.; Mengersen, K.; Wang, H.; Tayphasavanh, F.; Darasavong, K.;
Holmes, N. S.
Full Source: Environmental Science & Technology [online computer file] 2011, 45(3),
882-889 (Eng)
Is exposure to silica associated with lung cancer in the absence of silicosis? A
meta-analytical approach to an important public health question
This report investigated whether exposure to silica is associated with lung cancer risks in
individuals without silicosis. The authors searched the PubMed referece data base from
1966 through 1/2007 for reports of lung cancer in silica-exposed persons without and with
silicosis. To explore heterogeneity between studies, a multi-stage strategy was employed.
First, fixed-effect summaries (FES) and corresponding 95% confidence intervals (CI) for
various combinations of studies were calculated, weighting individual results by their
precision. The homogeneity of the contributing results was examined using ø2 statistics.
Where there was evidence of substantial heterogeneity, the CI around the FES was
increased to take account of the between-study variability. Random-effect summaries and
their CI for identical combinations of studies were also computed. Meta regression was
used to explore interactions with covariates. To draw comparisons, parallel analyses were
performed for non-silicotics and for silicotics. The results showed the persistence of a
significant link between silicosis and lung cancer since the characterisation in 1997 of
silica as a human carcinogen [the estimates of lung cancer relative risks (RR) exceeded
unity in each of 38 eligible studies of silicotics published until 1/2007, averaging 2.1 in
analyses based on both fixed and random effect models (95% CI ) (2.0-2.3) and (1.9-2.3),
respectively)] does not resolve our study question, namely whether exposure to silica
levels below those required to induce silicosis are carcinogenic. Importantly, the author‘s
detailed examination of 11 studies of lung cancer in silica-exposed individuals without
silicosis included only three with data allowing adjustment for smoking habits. They yielded
a pooled RR est. of 1.0 [95% CI ) (0.8-1.3)]. The other eight studies, with no adjustment for
smoking habits, suggested a marginally elevated risk of lung cancer [RR ) 1.2; 95% CI
(1.1-1.4)], but with significant heterogeneity between studies. The authors concluded that
further research should concentrate on silica exposures both above and below those that
induce silicosis, so that the shape of the exposure-response relationship may be identified,
with adjustments for likely confounding factors including silicosis. Time-dependent
information on silicosis and on silica dust is required as well as the application of methods
like G-estimation to answer the important public health question: Is silicosis a necessary
condition for the elevation of silica-associated lung cancer risks.
Authors: Erren, Thomas C.; Glende, Christine B.; Morfeld, Peter; Piekarski, Claus
Full Source: International Archives of Occupational and Environmental Health 2009, 82(8),
997-1004 (Eng)

Security booth with particle collector for the detection of warfare and explosives
A security booth collects particles from a person being investigated and standing in the
booth based on air flow technology and the interplay of fan nozzles and round spray
nozzles. In this study a funnel made of aluminium sheet metal conveyed the collected
particles into a collector supported by the round spray nozzles installed at the bottom of
the security booth. The air flow was controlled by a Siemens logic circuit which includes
relays and pressure reducers such that the particles are transferred into the funnel. The
security booth allowed the analysis of all body parts of the person and the clothes
simultaneously. Signal lights were to indicate whether or not a person being investigated
carries explosives or military warfare or toxic gases.
Authors: Gerling, Andrea; Gerling, Hans-Dieter
Full Source: DE Application 202,009,003,163, 5 Mar 2009; 7pp. (German)

Apparatuses for personal air filter
One type of personal air filtering system includes nasal plugs to be inserted into the
nostrils and a main body worn between the nose and mouth. In another type it has a
housing that prevents exhaled air from entering the air filter disposed in the housing. More
recent type, this personal air filtering system has separate vents for inhalation and
Author: Macy, Brad, Jr.
Full Source: PCT International Application 2009/609,014, 30 Oct 2009; 44pp. (English)

Nano-safety science for assuring the safety of nanomaterials
Nanotechnology developments have fostered the widespread use of a diverse array of
nanomaterials such as nanosilicas and carbon nanotubes. Because of its unique
physiochemical properties, such as conductivity, strength, durability, and chemical
reactivity nanomaterials are already being used in electronics, sunscreens, cosmetics, and
medicines. The advent of nanomaterials has also provided extraordinary opportunities for
biomedical applications, however, public concern about their potential risks to human
health has been raised due to the increasing use of nanomaterials. In particular, recent
reports have indicated that carbon nanotubes induce severe inflammation and
mesothelioma-like lesions in mice. Therefore the authors attempted to elucidate the
pharmacodynamics and safety of nanomaterials in order to develop novel, safe
nanomaterials and to establish scientifically based regulations. They concluded that this
study helps to improve the quality of human life by establishing standards for the safe use
of nanomaterials.
Authors: Yoshioka, Yasuo; Yoshikawa, Tomoaki; Tsutsumi, Yasuo
Full Source: Nippon Eiseigaku Zasshi 2010, 65(4), 487-492 (Japan)

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