ENVIRONMENTAL

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					ENVIRONMENTAL

~dEnvironmental
~tInvestigation of selenium levels in environment and human body in
Gaomi City and Zichuan District of Shandong Province in 2005.
~w2010-07-29
Lijiaying Township in Gaomi City of Weifang City, Zhaili Township and
Longquan Township in Zichuan District of Zibo City were selected. Two
farming soil samples at different spot, local wheat and corn,
residents nail samples from 3 to 4 families were collected in each
natural village in the investigated towns. The contents of selenium
were detected by 2,3-diamino naphthalene fluorescence method. In
Lijiaying, selenium was deficient in soil, wheat, corn, above
selenium deficiency diagnosis and below selenium-adequate level in
the nail, while in Zhaili and Longquan, the selenium level in the
soil, wheat, corn, nails was adequate. The external environment is
selenium deficient in Lijiaying, selenium adequate in Longquan and
Zhaili.
Authors: Bian, Jianchao; Yun, Zhongjie; Liu, Yuan; Song, Shuliang;
Qin, Qiliang; Liu, Chuanjiao; Zhai, Naiyao; Ge, Xiangjin; Jiang,
Yuting
Full Source: Zhongguo Difangbingxue Zazhi 2009, 28(4), 446-448
(China).

~dEnvironmental
~tPredicting Changes in PM Exposure Over Time at U.S. Trucking
Terminals Using Structural Equation Modelling Techniques
~w2010-07-29
This study analyses the temporal variability of occupational and
environmental exposures to fine particulate matter in the U.S.
trucking industry and tests the predictive ability of a novel
multilayer statistical approach to occupational exposure modelling
using structural equation modelling (SEM) techniques. For these
purposes, elemental carbon mass in six U.S. trucking terminals were
measured twice during the same season up to 2 years apart, observing
concentrations in the indoor loading and outdoor background location
as well as in the truck cabs of local drivers while on the road.
There was a general trend toward higher exposures during the second
sampling trips; however, these differences were statistically
significant in only a few cases and were largely attributable to
changes in weather patterns. Once accounting for systematic
prediction errors in background concentrations, the SEM approach
provided a strong fit for work-related exposures in this occupational
setting.
Authors: Davis, Mary E.; Laden, Francine; Hart, Jaime E.; Garshick,
Eric; Blicharz, Andrew; Smith, Thomas J.
Full Source: Journal of Occupational and Environmental Hygiene 2009,
6(7), 396-403 (USA).

~dEnvironmental
~tAirborne enteric coliphages and bacteria in sewage treatment plants
~w2010-07-29
The concentrations of airborne culturable microorganisms were
determined in wastewater and sludge treatment processes of seven
sewage treatment plants. Two types of coliphages, Salmonella and
total viable bacteria were sampled by the BioSampler and the numbers
of faecal coliforms and enterococci were obtained from the Andersen
6-stage impactor. The BioSampler recovered higher numbers of airborne
coliphage viruses than has been measured with other liquid samplers
in previous studies, suggesting that this sampler has improved
efficiency for sampling airborne coliphages. Airborne coliphages were
detected in many stages of the wastewater or sludge treatment
process. The highest microbiological air contaminations were found in
pre-treatment and aerated grit separation stages of the operation.
This was attributed to aerosolisation of microorganisms by mechanical
handling or forced aeration. Aeration and settling processes located
outdoors caused low microbial concentrations, but the brush aerator
released more microorganisms into the air. Our results emphasise the
necessity for controlling the exposure of sewage workers to airborne
microorganisms, especially in process areas that involve mechanical
agitation or forced aeration of wastewater.
Authors: Heinonen-Tanski, Helvi; Reponen, Tiina; Koivunen, Jari.
Full Source: Water Research 2009, 43(9), 2558-2566 (Finland).

MEDICAL

~dMedical
~tZinc protects human peripheral blood lymphocytes from
Cr(III)(phenanthroline)3-induced apoptosis.
~w2010-07-29
The authors have studied the effect of Cr(III)(phen)3 [(tris(1,10-
phenanthroline) chromium(III) chloride)] on lymphocytes in order to
find out if metallothioneins (MTs) are produced in the process. The
authors also investigated whether zinc pre-treatment is able to
protect cells from apoptosis reported to occur for this compound. MT
synthesis is induced by Cr(III)-(phen)3, and it has been identified
as the MT-3 isoform through RTPCR which has not been reported
earlier. By zinc pre-treatment, this apoptosis is reversed as
inferred from cytotoxicity studies, Annexin-V/PI staining, ethidium
bromide/acridine orange staining, and DNA fragmentation pattern and
ultrastructural investigations using TEM and SEM. The zinc pre-
treatment reduces the amount of ROS produced by Cr(III)(phen)3. The
MT-1a and 1b synthesised by zinc is possibly able to scavenge, which
is one of the early signalling molecules that lead to apoptosis. Zinc
pre-treatment also reverses the changes in downstream signalling
events such as mitochondrial membrane potential, ATP levels, and the
activation of caspase-3. This is the first report on the induction of
MT-3 in lymphocytes due to a metal stress or any other stimuli. Even
though MT-3 is synthesised here, apoptosis still occurs due to ROS
production on Cr(III)(phen)3 exposure when the cells have not been
primed with zinc.
Authors: Sankaramanivel, Sundararaj; Rajaram, Anantanarayanan;
Rajaram, Rama.
Full Source: Toxicology and Applied Pharmacology 2010, 243(3), 405-
419 (India).

~dMedical
~tEvaluation of salidroside in vitro and in vivo genotoxicity
~w2010-07-29
It is reported that salidroside, the main component of a traditional
Chinese medicine, Rhodiola rosea, has the efficacy of protecting
Coxsackie virus impairment. As part of a safety evaluation on
salidroside for use in the treatment of viral myocarditis, the
present study evaluated potential genotoxicity of salidroside by
using the standard battery of tests recommended by the State Food and
Drug Administration of China. The results showed that salidroside was
not genotoxic under the conditions of the reverse mutation assay,
chromosomal aberrations assay, and mouse micronucleus assay
conditions. The anticipated clinical dose seems to be smaller than
the doses administered in the genotoxicity assays. With confirmation
from further toxicity studies, salidroside would hopefully prove to
be a safe anti-Coxsackie virus agent.
Authors: Zhu, Jiangbo; Wan, Xuying; Zhu, Yuping; Ma, Xili; Zheng,
Yiwen; Zhang, Tianbao
Full Source: Drug and Chemical Toxicology (1977) 2010, 33(2), 220-226
(China).

~dMedical
~tEffects of industrial lead exposure on coagulation system
~w2010-07-29
Lead is environmental and/or occupational toxicant. It has not well
known whether it has effects on coagulation system or not. Therefore,
we aimed to investigate how coagulation system is affected by the
level of elevated blood lead. Fifty-two occupational lead exposure
patients applied with lead intoxication symptoms. Blood examples of
patients were obtained for lead level, platelet count, in-vitro
bleeding time, prothrombine time, partial thromboplastin time (aPTT),
fibrinogen, thrombin time, protein C, protein S and antithrombin III.
The patients are evaluated according to three groups as mild,
moderate and severe. Mean blood lead levels were 71,15. Mean values
results of primary and secondary hemostasis and physiology
coagulation inhibitors tests were in normal ranges, except fibrinogen
degree. Despite mean fibrinogen degree being under normal ranges,
statistically significant difference between the groups was not
detected. Mean aPTT and protein degrees were in normal ranges,
however, compared with the mild toxicated group statistically
important prolongment in aPTT and reducement in protein S degrees
detected in moderate-toxicated group. As a result, although our
results need suggestion by in vivo and in vitro studies, it is
concluded that hemostatic parameters excluding fibrinogen were not
affected by mild and moderate degree elevation of blood lead.
Authors: Mazicioglu, M. Mumtaz; Kaynar, Leylagul; Cetin, Aysun;
Mumcuoglu, Haluk; Saraymen, Recep; Karadag, Ozkan Kaan.
Full Source: Erciyes Tip Dergisi 2008, 30(3), 150-156 (Turkey).

~dMedical
~tEffect of silver nanoparticles on functioning of the human body
~w2010-07-29
Nanotechnology is the most promising field of science for generating
new application in medicine, textiles and also in the other branch of
industry. Most prominent nanoproducts are nanosilver particles.
Usually nanosilver particles are smaller than 100 nm and contain 20-
15.000 silver atoms. Researches proved than silver in nanoscale
exhibit extraordinary physical, chemical and biological properties.
Due to this fact, use of nanosilver particles is becoming more and
more prevalent in many fields of industry. With the widespread and
usage of new technologies there is, however, connected the risk of
scant insights into interaction of nanoparticles with both
microorganisms and human body. Biodistribution, organ accumulation or
cytotoxicity of nanosilver is only a few of many problems appears in
the last research. Currently is investigated impact of nanosilver
particles on respiratory system, skin and gastrointestinal tract.
These are only preliminary results, but we can be certain that
silver-based products should be used carefulness.
Authors: Bacciarelli, Anna; Kolodziejczyk, Marek; Rybicki, Edward.
Full Source: Barwniki, Srodki Pomocnicze 2008, 52(4), 99-113
(Poland).

OCCUPATIONAL

~dOccupational
~t30 years follow up study: the dose-response relationship of
asbestos exposure and asbestosis
~w2010-07-27
In this study, the authors investigated the dose-response
relationship of asbestosis incidence in the asbestos workers. A fixed
prospective cohort was established in which 338 Male exposed workers
employed for at least one year in asbestos plant in 1 Jan 1972, were
chosen as study cohort, and the asbestos dust concentration records
of all the workplaces and the incidences of asbestosis during the
past 30 years (1972-2002) were collected. The accumulative exposure
amount added up to the product of the concentration and the exposure
time, and the dose-response relationship between asbestos and
asbestosis incidence was established by the method of life table. The
maximum allowable concentration of asbestos dust was predicted as
3.9mg/m3 according to the presumption that the workers would work for
40 years and the incidence of asbestosis would be controlled under
1%. The authors concluded that the results suggest that the present
hygienic standard of asbestos dust(MAC) in our country is reasonable.
Authors: Deng, Qian; Lan, Ya-jia; Wang, Mian-zhen
Full Source: Xiandai Yufang Yixue 2009, 36(11), 2027- 2028, 2032 (Ch)

~dOccupational
~tBase excision repair gene polymorphisms and susceptibility of
chromosomal damage of vinyl chloride monomer exposed workers in China
~w2010-07-27
In the present study, the authors investigated the relationship
between base excision repair gene polymorphisms and susceptibility of
chromosomal damage in Chinese workers exposed to vinyl chloride
monomer (VCM). Cytokinesis-block micronucleus (CB-MN) test was used
to detect chromosome damage in peripheral lymphocytes for 185 VCM-
exposed workers. Genotypes of ADPRT Val762Ala and TDG Gly199Ser were
identified by creating restriction site combined with restriction
fragment length polymorphism (CRSRFLP). Genotypes of APE1 Ile64Val
were identified by PCR-RFLP technique. The results demonstrated an
increased risk of chromosome damage for individuals carrying TDG
199Gly/Ser + Ser/Ser genotypes compared with those carrying Gly/Gly
genotype (FR ) 1.198, 95% CI: 1.026-1.397). Female workers had an
increased risk of chromosome damage compared with male workers (FR )
1.172, 95% CI: 1.004-1.366). The risk of chromosomal damage for VCM-
exposed workers equal to or older than 36 years of age was 1.316 (95%
CI: 1.130-1.531) times of those younger than 36 years old. The
genetic polymorphisms of APE1 Ile64Val and ADPRT Val762Ala were not
related to the risk of chromosomal damage. The authors concluded that
VCM-exposed workers carrying TDG 199Gly/Ser + Ser/Ser genotypes
tended to be more susceptible to chromosomal damage induced by VCM.
Authors: Miao, Wenbin; Wang, Wei; Qiu, Yulan; Wu, Canjun; Ji, Fang;
Xia, Zhaolin
Full Source: Fudan Xuebao, Yixueban 2008, 35(2), 161-166 (Ch)

~dOccupational
~tDNA damage and methylation of DNA repair gene in vinyl chloride-
exposed workers
~w2010-07-27
This study examined the relationship between DNA damage induced by
vinyl chloride monomer (VCM) exposure and the promoter methylation of
O6-methylguanine-DNA methyltransferase gene MGMT as well as mismatch
repair gene hMLH1. VCM exposed workers were divided into DNA damage
group (72 individuals) and control group (43 individuals) according
to the frequency of cytokinesis-block micronucleus. Methylation-
specific PCR (MSP) was used to analyse the repair gene promoter
methylation status of peripheral blood lymphocytes from VCM exposed
workers. The MSP results revealed that there was no detectable
promoter methylation of hMLH1 in both DNA damaged group and non-
damaged group. The frequency of MGMT promoter methylation was 6.9%
(5/72) in DNA damaged group and 0% in non-damaged group. The authors
concluded that the results suggest that aberrant methylation of MGMT
gene might occur during DNA damage, reflecting the early adverse
effect induced by VCM exposure.
Authors: Liu, Jing; Wang, Wei; Qiu, Yulan; Sun, Pin; Miao, Wenbin;
Wu, Fen; Xia, Zhaolin
Full Source: Fudan Xuebao, Yixueban 2008, 35(2), 190-193 (Ch)

~dOccupational
~tA newly recognised occupational hazard for US electronic recycling
facility workers: polybrominated diphenyl ethers
~w2010-07-27
In this study, the authors reviewed the industrial uses, biological
effects, and evidence for health risks of polybrominated di-Ph ethers
(PBDEs), including the current use of common marketed PBDE mixtures.
In addition, previous data on PBDE exposure in occupational and
environmental settings, including past studies in electronic
recycling facilities was analysed. The study also summarises new
estimates of PBDE exposure among electronic recycling facility
workers, along with the recommendations for monitoring and protection
of exposed workers. To describe a newly recognised US occupational
health hazard, polybrominated di-Ph ether (PBDE) flame retardant
exposure, to US workers at electronics recycling facilities to
communicate this information to occupational medicine physicians and
related health workers. Using PBDE air values reported from a
California electronic recycling facility and estimates of US food,
air and dust intake, electronic recycling facility workers' PBDE
exposure at this facility was estimated using multiple possible
scenarios. The authors then compared these estimates to intake
estimates for the US general population. Occupational PBDE study
findings from China, Sweden, and Norway where elevated environmental
or blood PBDE levels were detected in similar workers were reviewed.
An approximately 6-fold to 33-fold increase in the electronic
recycling facility workers' PBDE exposure was estimated compared with
the US general population. PBDE exposure in US electronic recycling
facilities is a largely unrecognised occupational health hazard. The
authors concluded that based on the results, the extent of worker
exposure in the US should be better characterised and steps taken to
lower levels of PBDEs in the workplace where exposure exists. Health
care providers, plant safety professionals, and government agencies
can play a role in recognising the problem and in decreasing worker
exposure.
Authors: Schecter, Arnold; Colacino, Justin A.; Harris, T. Robert;
Shah, Nirav; Brummitt, Sharon I.
Full Source: Journal of Occupational and Environmental Medicine 2009,
51(4), 435-440 (Eng)

~dOccupational
~tStudy on the relation between level of serum aluminium and chronic
cognition impairment in aluminium electrolytic worker
~w2010-07-27
This study explored the status of chronic cognition impairment and
its influencing factors in people with occupational exposure to
aluminium. The paper adopts MMSE questionnaire to investigate general
health state and status of chronic cognition impairment in 204
persons with occupational exposure to aluminium. The level of serum
aluminium were measured by the graphite furnace atomic absorption
spectrometry-(GF-AAS). By statistics analysis we found there were 24
occupational persons suffered chronic cognition impairment, and there
was significant difference in the score of MMSE between the two
groups (t)12.717, P<0.05). There was significant difference in the
items of MMSE such as time orientation, place orientation, language
immediate memory, attention and computation, delay recall, language
repeat and verbalisation between the two groups(P<0.05, t')3.332,
4.131, 2.387, 6.785, 3.938, 2.874 and 2.395). There was no relation
between chronic cognition impairment and age, working age, education,
dementia family history, head trauma history, thyropathy history and
psychosis history in those people(P>0.05). There was no significant
difference between the chronic cognition impairment and the level of
serum aluminium(MWU)111.5, P)0.646), but there was significant
difference between the level of serum aluminumg60íg / L group and
<60íg / L group(ø2 ) 7.190, P<0.05). The authors concluded that
occupational exposure to aluminium affects the status of chronic
cognition impairment, effective measure should be taken to control
the concentration of aluminium in the work place, and strengthen the
health examination among those workers.
Authors: Zhai, Jin-xia; Feng, A-juan; Zhang, Junqing; Fang, Si-xin
Full Source: Xiandai Yufang Yixue 2009, 36(11), 2018-2020 (Ch)

PUBLIC HEALTH

~dPublic Health
~tPredictors of Serum Dioxin, Furan, and PCB Concentrations among
Women from Chapaevsk, Russia
~w2010-07-27
Dioxins, furans, and polychlorinated biphenyls (PCBs) are persistent
and bioaccumulative toxic chemicals, which are ubiquitous in the
environment. In this study, the authors assessed predictors of their
serum concentrations among women living in a Russian town
contaminated by past industrial activity. Blood samples from 446
mothers aged 23-52 years were collected between 2003-2005 as part of
the Russian Children's Study. Serum dioxin, furan, and PCB
concentrations were quantified using high-resolution gas
chromatography-mass spectrometry. Potential determinants of exposure
were collected through interviews. Multivariate linear regression
models were used to identify predictors of serum concentrations and
toxic equivalencies (TEQs). Results indicated a median total PCB
concentration and total TEQs of 260 ng/g lipid and 25 pg TEQ/g lipid,
respectively. In multivariate analyses, both total PCB concentrations
and total TEQs increased significantly with age, residential
proximity to a local chemical plant, duration of local farming, and
consumption of local beef. Both decreased with longer breastfeeding,
recent increases in body mass index, and later blood draw date. The
authors concluded that these demography and lifestyle predictors
showed generally similar associations with the various measures of
serum dioxins, furans, and PCBs.
Authors: Humblet, Olivier; Williams, Paige L.; Korrick, Susan A.;
Sergeyev, Oleg; Emond, Claude; Birnbaum, Linda S.; Burns, Jane S.;
Altshul, Larisa; Patterson, Donald G.; Turner, Wayman E.; Lee, Mary
M.; Revich, Boris; Hauser, Russ
Full Source: Environmental Science & Technology 2010, ACS ASAP
(English)

~dPublic Health
~tGeneration and characterisation of diesel exhaust in a facility for
controlled human exposures
~w2010-07-27
An idling medium-duty diesel truck operated on ultralow sulphur
diesel fuel was used as an emission source to generate diesel exhaust
for controlled human exposure. Repeat tests were conducted on the
Federal Test Procedure using a chassis dynamometer to demonstrate the
reproducibility of this vehicle as a source of diesel emissions.
Exhaust was supplied to a specially constructed exposure chamber at a
target concentration of 100 íg á m-3 diesel particulate matter (DPM).
Spatial variability within the chamber was negligible, whereas
emission concentrations were stable, reproducible, and similar to
concentrations observed on the dynamometer. Measurements of nitric
oxide, nitrogen dioxide, carbon monoxide, particulate matter (PM),
elemental and organic carbon, carbonyls, trace elements, and
polycyclic aromatic hydrocarbons were made during exposures of both
healthy and asthmatic volunteers to DPM and control conditions. The
effect of the so-called "personal cloud" on total PM mass
concentrations was also observed and accounted for. Conventional lung
function tests in 11 volunteer subjects (7 stable asthmatic) did not
demonstrate a significant change after 2-h exposures to diesel
exhaust. The authors concluded that the findings from this study
demonstrate that this facility can be effectively and safely used to
evaluate acute responses to diesel exhaust exposure in human
volunteers.
Authors: Sawant AA, Cocker DR 3rd, Miller JW, Taliaferro T, Diaz-
Sanchez D, Linn WS, Clark KW, Gong H Jr.
Full Source: Journal of Air & Waste Management, 58 (6), 829-837, Eng

~dPublic Health
~tPersonal child and mother carbon monoxide exposures and kitchen
levels: Methods and results from a randomised trial of wood fired
chimney cookstoves in Guatemala (RESPIRE)
~w2010-07-27
During the first randomised intervention trial (RESPIRE: Randomised
Exposure Study of Pollution Indoors and Respiratory Effects) in air
pollution epidemiology, the authors pioneered application of passive
carbon monoxide (CO) diffusion tubes to measure long-term personal
exposures to wood smoke. This literature reports the protocols and
validations of the method, trends in personal exposure for mothers
and their young children, and the efficacy of the introduced improved
chimney stove in reducing personal exposures and kitchen
concentrations. Passive diffusion tubes originally developed for
industrial hygiene applications were deployed on a quarterly basis to
measure 48-h integrated personal carbon monoxide exposures among 515
children 0-18 months of age and 532 mothers aged 15-55 years and area
samples in a subsample of 77 kitchens, in households randomised into
control and intervention groups. Instrument comparisons among types
of passive diffusion tubes and against a continuous electrochemical
CO monitor indicated that tubes responded nonlinearly to CO, and
regression calibration was used to reduce this bias. Before stove
introduction, the baseline arithmetic (geometric) mean 48-h child
(n)270), mother (n)529) and kitchen (n)65) levels were, respectively,
3.4 (2.8), 3.4 (2.8) and 10.2 (8.4) p.p.m. The between-group analysis
of the 3355 post-baseline measurements found CO levels to be
significantly lower among the intervention group during the trial
period: kitchen levels: -90%; mothers: -61%; and children: -52% in
geometric means. No significant deterioration in stove effect was
observed over the 18 months of surveillance. The reliability of these
findings is strengthened by the large sample size made feasible by
these unobtrusive and inexpensive tubes, measurement error reduction
through instrument calibration, and a randomised, longitudinal study
design. The authors concluded that the findings from the first
randomised trial of improved household energy technology in a
developing country demonstrated that a simple chimney stove can
substantially reduce chronic exposures to harmful indoor air
pollutants among women and infants.
Authors: Smith, Kirk   R.; Mccracken, John P.; Thompson, Lisa; Edwards,
Rufus; Shields, Kyra   N.; Canuz, Eduardo; Bruce, Nigel
Full Source: Journal   of Exposure Science & Environmental Epidemiology
2010, 20(5), 406-416   (English)

~dPublic Health
~tMineral analysis of human hair in the assessment of bioavailability
of nutritive and toxic elements of industrial origin from food
~w2010-07-27
In this study, inductively coupled plasma optical emission
spectrometry was used for the detection of 25 major and trace element
concentrations in scalp hair samples from a population of 159
students and employees of Wroclaw University of Technology. The
effect of frequency of egg consumption and drinking milk, type of
consumed eggs and bread buttering, the consumption of cottage and
mould cheese, the source of fruits and vegetables, degree of food
processing and the consumption of meals at the academic cafeteria on
the mineral content of hair was analysed. The results were elaborated
statistically.
Authors: Chojnacka, Katarzyna; Zielinska, Agnieszka; Michalak,
Izabela; Gorecka, Helena; Mikulewicz, Marcin; Gorecki, Henryk Full
Source: Przemysl Chemiczny 2010, 89(4), 342-347 (Polish)

~dPublic health
~tReview on the effects of exposure to spilled oils on human health
~w2010-07-27
Harmful effects of oil spills on diverse flora and fauna species have
been extensively studied. Nevertheless, only a few studies have been
compiled in the literature dealing with the repercussions of oil
exposure on human health; most of them have focused on acute effects
and psychological symptoms. In this study, the authors gathered
all these studies and analysed the possible consequences of this kind
of complex exposure in the different aspects of human health. Studies
found on this topic were related to the disasters of the Exxon
Valdez, Braer, Sea Empress, Nakhodka, Erika, Prestige, and Tasman
Spirit oil tankers. The majority of them were cross-sectional; many
did not include control groups. Acute effects were evaluated taking
into account vegetative-nervous symptoms, skin and mucous
irritations, and also psychological effects. Genotoxic damage and
endocrine alterations were assessed only in individuals exposed to
oil from Prestige. The authors concluded that the results of the
reviewed articles clearly support the need for biomonitoring human
populations exposed to spilled oils, especially those individuals
involved in the cleanup, in order to evaluate not only the possible
immediate consequences for their health but also the medium- and
long-term effects, and the effectiveness of the protective devices
used.
Authors: Aguilera, Francisco; Mendez, Josefina; Pasaro, Eduardo;
Laffon, Blanca
Full Source: Journal of Applied Toxicology 2010, 30(4), 291-301 (Eng)

SAFETY

~dSafety
~tKinetic simulation of gas explosion and inhibition mechanism in
enclosed space
~w2010-07-29
Through amending the SENKIN code of CHEMKIN III chemical kinetics
package, the computational model of gas explosion in a constant
volume bomb was built, and the detailed reaction mechanisms
(including 53 species, 325 reactions) were adopted. The trends of
variation of the mole fractions of reactants, activation centres in
the explosion process, and the mole fractions of catastrophic gases
after explosion were analysed by using this model. Furthermore,
through the sensitivity analysis of the reaction mechanisms of gas
explosion, the key reactions that affected gas explosion and
formation of catastrophic gases were identified. At the same time,
the inhibition mechanism of water on gas explosion and formation of
catastrophic gases were analysed. The results showed that the
temperature and pressure were 2700 K° and 0.22 MPa respectively,
after gas explosion when the mixed gas had no water. When the mole
fraction of water in the mixed gas was 10%, the temperature and
pressure were 2580 K° and 0.21 MPa respectively. When the mole
fraction of water in the mixed gas was 15%, the temperature and
pressure decreased by 180 K° and 0.025 MPa respectively, against the
case that the mixed gas had no water. Furthermore, the water in the
mixed gas would inhibit gas explosion and the formations of CO, CO2
and NO2.
Authors: Liang, Yuntao; Zeng, Wen.
Full Source: Huagong Xuebao (Chinese Edition) 2009, 60(7), 1700-1706
(China).

~dSafety
~tSafety management of nanoparticle materials in university labs
~w2010-07-29
The development of nanotechnology leads to substantive changes in
various fields, which dramatically improves the effectiveness of new
materials. However, as the products are used in human life,
unexpected behaviour of toxicology is reported successively.
Nanoparticle materials have a lot of special physicochemical
properties compared with conventional materials, which can result in
some special biological effects for their small size. This paper
discussed how to dispose and manage nanoparticles in labs before
their physicochemical properties and their toxicology and bioactive
mechanisms were completely comprehended.
Authors: Zhou, Gu; Li, Song.
Full Source: Shiyanshi Yanjiu Yu Tansuo 2009, 28(4), 160-162, 171
(China).

~dSafety
~tNanoparticles can be safely handled
~w2010-07-29
The Nanocare project of the chemical industry is carried out together
with academic institutions including the aggregation and
agglomeration behaviour of nanoparticles and the stability of these
structures. In addition the project is compared, available methods
for the detection of airborne particles and aerosols by intentionally
modified materials, which serve as a reference. Moreover, the
industry is involved in projects with similar objectives (Nanosafe
II, Nanoderm, tracer).
The International Standardization Organization (ISO) and the German
Institute for Standardization (DIN) initializes parallel occupational
measurement techniques, including sampling and treatment, monitoring,
reference materials, progressing.
Author: Jopp, Klaus
Full Source: LaborPraxis 2009, 33(12), 20-21 (Germany).

				
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