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~tFormation of polychlorinated dibenzo-dioxins (PCDD), dibenzofurans
(PCDF) and naphthalenes (PCN) in a laboratory-scale waste combustion
The research presented in this chapter contributes to knowledge about
the combustion-based formation of dioxins and dioxin-like compounds.
Dioxins are among the most toxic substances known to man, and are
formed as by products of industrial processes, including waste
incineration. Although the emissions of dioxins from waste
incineration facilities have been greatly reduced by the improved
efficiency of pollution abatement technologies, the materials that
remain (ashes and filters) are highly contaminated and are thus
classified as hazardous waste. The principal objective of this
research was to elucidate the pathways by which dioxins and dioxin-
like compounds are formed in flue gas in the post-combustion zone of
a laboratory- scale reactor during well-controlled combustion of
waste. The potential benefits of this improved understanding include
detoxification of waste incineration residues and further reduction
of harmful emissions to air, which could reduce or even eliminate the
need for costly and potentially hazardous treatment. Polychlorinated
dibenzo-p-dioxins(PCDD) and dibenzofurans (PCDF) were formed rapidly
in the post combustion zone of the lab.-scale reactor, mainly as the
temperature declined from 650°C to 400°C, with a high dependency on
sufficient residence time within a specific temperature interval.
Prolonged residence at temperatures above 450°C led to a reduction in
the concentration of PCDDs formed. The isomer distribution patterns
of the PCDDs, PCDFs and polychlorinated naphthalenes (PCNs) in the
flue gas indicated that the formation of PCDDs was largely influenced
by condensation of chlorophenols and, to a lower extent, by
chlorination reactions. The abundance of 1,9-substituted PCDFs was
low, suggesting that chlorine substitution reactions were not
favoured at positions adjacent to the oxygen bridges. The effects of
injection of aromatics compounds into the flue gas were compound-
dependent. Injection of naphthalene caused an increase in the
formation of monochlorinated naphthalene but not in other
chloronaphthalene homologues, probably because of insufficient
residence time at temperatures conducive to further chlorination.
Injection of dibenzo-p-dioxin appeared to result in its
decomposition, chlorination and re-condensation to form PCDDs and
PCDFs, whereas the introduction of dibenzofuran and fluorene led to a
reduction in the concentrations of PCDDs in the flue gas.
Author: Jansson, Stina
Full Source: Heterogeneous Combustion, 77-109 (English)

~tDetection of illicit drugs on surfaces using direct analysis in
real time (DART) time-of-flight mass spectrometry
Methamphetamine (meth) from meth syntheses or habitual meth smoking
deposited on household surfaces poses human health hazards. The U.S.
State Departments of Health require decontamination of sites where
meth was synthesised (meth labs) before they are sold. National
Institute for Occupational Safety and Health (NIOSH) methods for meth
analysis require wipe sampling, extension, clean-up, solvent
exchange, derivation, and/or mass spectral analysis using selected
ion monitoring. Rapid and inexpensive analyses could screen for drug-
contamination within structures with greater spatial resolution,
provide real-time analyses during decontamination, and provide
thorough documentation of successful clean ups. Here in an auto
sampler/open-air ion source time-of-flight mass spectrometric
technique is described that required only direct sampling using
cotton-swab wipes. Each wipe sample collection required 2 minute and
data acquisition required only 13 drugs per sample. Optimum collision
induced dissociation, voltages, desorption gas temperatures and wipe
sample solvents were detected for 11 drugs. Peaks were observed in
analyte-ion traces for 0.025 íg/100 cm2 of meth and seven other
drugs. This level is half the detection limit of NIOSH methods and
one-fourth of the lowest U.S state decontamination limit for meth.
Dynamic ranges of 100 in concentration were demonstrated for eight
drugs, which is sufficient for a screening technique. The
volatilities of 11 drugs deposited on glass were detected. The pick-
up of the drugs by solvent-soaked cotton-swab wipes from glass
relative to acrylic latex paint was also compared.
Authors: Grange, Andrew H.; Sovocool, G. Wayne
Full Source: Rapid Communications in Mass Spectrometry 2011, 25(9),
1271-1281 (English)


~tAnalysis of the changes of the serum concentration of TNF-r, IL-6
and paraquat in the patients with paraquat poisoning
This paper aims to investigate the changes of serum concentration of
tumour necrosis factor-R (TNF-R), interleukin-6 (IL-6)and paraquat
(PQ) in the patients with PQ poisoning and to explore the mechanisms
of multiple organ failure (MOF) caused by PQ poisoning. Fifteen
patients with PQ poisoning were selected for this study. The enzyme
linked immunosorbent assay (ELISA) was used for detecting the serum
concentration of TNF-R and IL-6, and the high performance liquid
chromatography (HPLC) was used for detecting the serum concentration
of PQ at 4, 24 and 96 h after admission. Twenty Normal individuals
served as controls. The serum concentration of TNF-R and IL-6 in the
patients with PQ poisoning had abnormal increase at 4 h after
admission, and were progressively increased with the extension of
time (all P<0.01), and TNF-R and IL-6 were significantly associated
in the patients with PQ poisoning. The serum concentration of PQ was
maintained in high level, and there was no difference at the
different points (P>0.05). Both TNF-R and IL-6 were not significantly
associated with the serum concentration of PQ. The high serum
concentration of PQ induces progressive increase of serum
concentration of TNF-R and IL-6, and leads to systemic inflammatory
response syndrome (SIRS), then to MOF.
Authors: Li, Chuang; Hao, Tong-qin; Liu, Jian-ping; Liang, Dong-liang
Full Source: Zhongguo Jijiu Yixue 2010, 30(8), 739-741 (Ch)

~tAlternative expression and sequence of human elongation factor-1ä
during malignant transformation of human bronchial epithelial cells
induced by cadmium chloride
Objective: To study the alternative expression and sequence of human
elongation factor-1ä (human EF-1ä p31) during malignant
transformation of human bronchial epithelial cells induced by cadmium
chloride (CdCl2) and its possible mechanism. Methods: Total RNA was
isolated at different stages of transformed human bronchial
epithelial cells (16HBE) induced by CdCl2 at a concentration of 5.0
IM. Special primers and probe for human EF-1ä p31 were designed and
expression of human EF-1ä mRNA from different cell lines was detected
with fluorescent quantity. PCR technique EF-1ä cDNA from different
cell lines was purified and cloned into pMD 18-T vector followed by
confirming and sequencing analysis. Results: The expressions of human
EF-1ä p31 at different stages of 16HBE cells transformed by CdCl2 was
elevated (P<0.01 or P<0.05). Compared with their corresponding non-
transformed cells, the over expression level of EF-1ä p31 was
averagely increased 2.9 folds in Cd-pre-transformed cells, 4.3 folds
in Cd-transformed cells and 7.2 folds in Cd-tumorigenic cells. No
change was found in the sequence of over-expressed EF-1ä p31 at
different stages of 16HBE cells transformed by CdCl2. Conclusion:
Over-expression of human EF-1ä p31 is positively correlated with
malignant transformation of 16HBE cells induced by CdCl2, but is not
correlated with DNA mutations.
Authors: Lei, Yi-Xiong; Wang, Min; Wei, Lian; Lu, Xi; Lin, Hua-Zhao
Full Source: Biomedical and Environmental Sciences 2010, 23(2), 151-
157 (Eng)

~tBio-effects of CdTe quantum dots on human umbilical vein
endothelial cells
Quantum dots (QDs) hold great potential for applications in nano
medicine, however, their health effects are largely unknown. In the
present study, the cytotoxicity and genotoxicity of CdTe QDs were
examined in human umbilical vein endothelial cells (HUVECs). The QDs
exhibited a dose-dependent inhibitory effect on cell growth. It was
shown that after a 12 h treatment QDs at 1, 10, and 50 ígáml-1
induced formation of çH2AX foci, indicative of DNA damage, in a dose-
dependent manner. Moreover, QD treatment clearly induced the
generation of reactive oxygen species (ROS). Pretreatment with N-
acetyl-cysteine (NAC), a ROS scavenger, could inhibit the induction
of ROS by QDs, as well as the formation of çH2AX foci. Taken
together, our data indicate that CdTe QDs have cytotoxic and
genotoxic effects on HUVECs, and that ROS generation may be involved
in QD induced DNA damage.
Authors: Wang, Liping; Zhang, Jun; Zheng, Yifan; Yang, Jun; Zhang,
Qunwei; Zhu, Xinqiang
Full Source: Journal of Nanoscience and Nanotechnology 2010, 10(12),
8591-8596 (Eng)

~tSingle and concerted effects of benzo[a]pyrene and flavonoids on
the AhR & Nrf2-pathway in the human colon carcinoma cell line Caco-2
As phytochemicals have the potential to counteract adverse effects of
carcinogens, the authors investigated the influence of the flavonoids
quercetin and kaempferol on benzo[a]pyrene (BaP) mediated effects on
human colon cancer cells, Caco-2. The authors focused on concerted
effects on the expression of AhR and Nrf2 pathway components. In
contrast to kaempferol, BaP and quercetin efficiently induced CYP1A1,
CYP1A2 and CYP1B1-mRNA in Caco-2 cells. BaP not only acted via AhR
activation but sustainably also by increasing AhR and by down-
regulating AhRR mRNA. The flavonoids did not affect AhR expression
but counteracted the BaP mediated AhRR repression. Only quercetin was
found to induce AhRR mRNA. ARNT mRNA appeared to be slightly but
significantly down-regulated by BaP as well as by flavonoids while
expression of AIP was not or only slightly modulated. The Nrf2
pathway was activated by BaP and by the flavonoids shown by induction
of Nrf2 and several of its target genes such as NQO1, GSTP1, GSTA1
and GCLC. Induction effects of 10 ím BaP on Nrf2, GSTP1 and NQO1 were
abolished by the flavonoids. In summary, the authors showed that
quercetin supports AhR mediated effects. Both flavonoids, however,
may counteract the effects of BaP on expression of AhR, AhRR, Nrf2,
GSTP1 and NQO1. In conclusion, quercetin appears to have two faces, a
flavonoid-like one and a PAH-like one which supports Ahr-mediated
effects while kaempferol acts "just like a flavonoid". Thus,
flavonoids have to be treated individually with respect to their
anti-adverse activity.
Authors: Niestroy, Jeanette; Barbara, Alfonso; Herbst, Kathrin; Rode,
Sandra; van Liempt, Manuela; Roos, Peter H.
Full Source: Toxicology in Vitro 2011, 25(3), 671-683 (Eng)

~tCytotoxic and genotoxic effects of multi-wall carbon nanotubes on
human umbilical vein endothelial cells in vitro
Carbon nano-materials have multiple applications in various areas.
However, it has been suggested that exposure to nano-particles may be
a risk for the development of vascular diseases due to injury and
dysfunction of the vascular endothelium. Therefore, in the present
study, the cytotoxic and genotoxic effects of multi-wall carbon
nanotubes (MWCNTs) on human umbilical vein endothelial cells (HUVECs)
were evaluated. Optical and transmission electronic microscopy (TEM)
study showed that MWCNTs were able to enter cells rapidly, distribute
in the cytoplasm and intracellular vesicles and induce morphological
changes. Exposure to MWCNTs reduced the viability of HUVECs, and
induced apoptosis in HUVECs. Furthermore, MWCNTs could cause DNA
damage as indicated by the formation of çH2AX foci. MWCNTs also
affected cellular redox status, e.g., increasing intracellular
reactive oxygen species (ROS) and malondialdehyde (MDA) levels, as
well as altering superoxide dismutase (SOD) activity and glutathione
peroxidase (GSH-Px) levels. On the other hand, the free radical
scavenger N-acetyl-L-cysteine (NAC) pre-incubation can inhibit the
cytotoxic and genotoxic effects of MWCNTs. Taken together, these
results demonstrated that MWCNTs could induce cytotoxic and genotoxic
effects in HUVECs, probably through oxidative damage pathways.
Authors: Guo, Yuan-Yuan; Zhang, Jun; Zheng, Yi-Fan; Yang, Jun; Zhu,
Full Source: Mutation Research, Genetic Toxicology and Environmental
Mutagenesis 2011, 721(2), 184-191 (Eng)


~tRelationship between urinary 1-hydroxypyrene level and peripheral
blood lymphocyte chromosomal damage among coke oven workers
This study investigated the relationship between the urinary l-
hydroxypyrene level and cytokinesis block micronucleus (CBMN) in
peripheral blood lymphocyte in coke oven workers. One hundred and
fifty-eight workers from a coke plant and 158 referents without
occupational PAHs exposure were recruited in this study. Urinary
level of l-hydroxypyrene was measured by alkaline hydrolysis combined
with high performance liquid chromatography as an internal exposure
dose, and the chromosomal damage of peripheral blood lymphocyte was
evaluated with CBMN method. Personal information including
occupational history, age, gender, smoking and alcohol consumption,
was collected by questionnaire. The lymphocyte chromosomal damage
level expressed as frequency of CBMN in coke oven workers was
significantly higher than that of controls (3.32‰(2.90‰ versus
0.57‰(0.88‰, P<0.01) after adjusting for gender, age, smoking and
alcohol consumption, and correlation between urinary l-hydroxypyrene
concentrations and frequency of CBMN was found (Spearman partial
correlation coefficient)0.28, P<0.05) in coke oven workers. Three
hundreds and sixteen subjects were divided into three groups by their
urine 1-hydroxypyrene level (expressed as 0.11-0.70, 0.71-4.09 and
4.10-24.74 ímol/mol Cr). After adjusting for age, gender, smoking and
alcohol consumption by multiple nonparametric analysis of covariance,
the frequency of CBMN in the groups of 0.71-4.09 and 4.10-24.74
ímol/mol Cr were l.89‰(2.37‰ and 3.29‰(2.36‰, significantly higher
than that in the group of 0-0.70ímol/mol Cr (0.56‰(0.89‰) (P<0.05).
The authors concluded that based on the findings, under present PAHs
exposure levels, CBMN test could detect PAHs-induced genotoxicity in
coke oven workers.
Authors: Guan, Weijun; Liu, Nan; Pang, Shulan; Qi, Xiao; Xu, Guohui;
Liu, Yingli; Wang, Qian
Full Source: Zhonghua Laodong Weisheng Zhiyebing Zazhi 2010, 28(8),
561-564 (Ch)

~tSimulation Tests to Assess Occupational Exposure to Airborne
Asbestos from Artificially Weathered Asphalt-Based Roofing Products
Historically, asbestos-containing roof cements and coatings were
widely used for patching and repairing leaks. Although fibre releases
from these materials when newly applied have been studied, there is
almost no useful data on airborne asbestos fibre concentrations
associated with the repair or removal of weathered roof coatings and
cements, as most studies involve complete tear-out of old roofs,
rather than only limited removal of the roof coating or cement during
a repair job. The current study was undertaken to estimate potential
chrysotile asbestos fibre exposures specific to these types of
roofing products following artificially enhanced weathering. Roof
panels coated with plastic roof cement and fibred roof coating were
subjected to intense solar radiation and daily simulated
precipitation events for 1 yr and then scraped to remove the
weathered materials to assess chrysotile fibre release and potential
worker exposures. Analysis of measured fibre concentrations for hand
scraping of the weathered products showed 8-h time-weighted average
concentrations that were well below the current Occupational Safety
and Health Administration permissible exposure limit for asbestos.
However, there was visibly more dust and a few more fibres collected
during the hand scraping of weathered products compared to the cured
products previously tested. There was a notable difference between
fibres released from weathered and cured roofing products. In
weathered samples, a large fraction of chrysotile fibres contained
low concentrations of or essentially no magnesium and did not meet
the spectral, mineralogical, or morphological definitions of
chrysotile asbestos. The extent of magnesium leaching from chrysotile
fibres is of interest because several researchers have reported that
magnesium-depleted chrysotile fibres are less toxic and produce fewer
mesothelial tumours in animal studies than normal chrysotile fibres.
Authors: Sheehan, Patrick; Mowat, Fionna; Weidling, Ryan; Floyd, Mark
Full Source: Annals of Occupational Hygiene 2010, 54(8), 880-892

~tExposure to benzene induces oxidative stress, alters the immune
response and expression of p53 in gasoline filling workers
Chronic exposure to benzene can lead to deleterious effects on many
biological systems including blood and blood forming organs. During
the present study, the authors investigated the adverse effects of
benzene among workers occupationally exposed to benzene in India.
Four hundred twenty-eight gasoline filling workers occupationally
exposed to benzene and 78 unexposed individuals were recruited for
this study. Benzene concentration was detected by gas chromatography,
reactive oxygen species (ROS) by dichlorofluorescin diacetate (DCFH-
DA) method, malondialdehyde (MDA) by thiobarbituric acid reactive
substances assay (TBARS), total superoxide dismutase (T-SOD) by
RANSOD kit and glutathione (GSH) by 5,5'-dithiobis-(2-nitrobenzoic
acid) (DTNB) reaction, respectively. CD4, CD8, IgG were carried out
by using fluorescence activated cell sorter (FACS Calibur) and mRNA
expression of p53 by reverse transcriptase PCR (RT-PCR). A
significant increase in the concentration of benzene and its by-
products in both blood and urine were found in the workers compared
with the controls. The levels of ROS and MDA were significantly
elevated, and GSH and total T-SOD were decreased in the workers
compared with the controls. A statistically significant decrease in
the Ig levels, CD4T cells, CD4/CD8 ratio was observed in workers
(versus controls), whereas no significant difference was observed in
CD8T cells. P53 gene expression was markedly higher in workers than
in controls. The authors concluded that occupational exposure to
benzene causes oxidative stress, immune suppression and increases the
expression of tumour-suppressing gene p53 in gasoline filling
workers. These bio-functional markers might be useful in screening
and surveillance for occupational hazard.
Authors: Uzma, Nazia; Kumar, B. Santhosh; Hazari, Mohammed Abdul
Full Source: American Journal of Industrial Medicine 2010, 53(12),
1264-1270 (Eng)

~tBiomarkers of chlorpyrifos exposure and effect in Egyptian cotton
field workers
Chlorpyrifos (CPF), a widely used organophosphorus pesticide (OP), is
metabolised to CPF-oxon, a potent cholinesterase (ChE) inhibitor, and
trichloro-2-pyridinol (TCPy). Urinary TCPy is often used as a
biomarker for CPF exposure, whereas blood ChE activity is considered
an indicator of CPF toxicity. However, whether these biomarkers are
dose related has not been studied extensively in populations with
repeated daily OP exposures. In this study, the authors determined
the relationship between blood ChE and urinary TCPy during repeated
occupational exposures to CPF. Daily urine samples and weekly blood
samples were collected from pesticide workers (n ) 38) in Menoufia
Governorate, Egypt, before, during, and after 9-17 consecutive days
of CPF application to cotton fields. Blood butyrylcholinesterase
(BuChE) and acetyl-cholinesterase (AChE) activities were compared
with the respective urinary TCPy concentrations in each worker.
Avereage TCPy levels during the middle of a 1- to 2-wk CPF
application period were significantly higher in pesticide applicators
(6,437 íg/g creatinine) than in technicians (184 íg/g) and engineers
(157 íg/g), both of whom are involved in supervising the application
process. The authors observed a statistically significant inverse
correlation between urinary TCPy and blood BuChE and AChE activities.
The no-effect level (or inflection point) of the exposure-effect
relationships has an average urinary TCPy level of 114 íg/g
creatinine for BuChE and 3,161 íg/g creatinine for AChE. The authors
concluded that these findings demonstrate a dose-effect relationship
between urinary TCPy and both plasma BuChE and red blood cell AChE in
humans exposed occupationally to CPF. The results will contribute to
future risk assessment efforts for CPF exposure.
Authors: Farahat, Fayssal M.; Ellison, Corie A.; Bonner, Matthew R.;
McGarrigle, Barbara P.; Crane, Alice L.; Fenske, Richard A.; Lasarev,
Michael R.; Rohlman, Diane S.; Anger, W. Kent; Lein, Pamela J.;
Olson, James R.
Full Source: Environmental Health Perspectives 2011, 119(6), 801-806

~tClinical outcomes of occupational exposure to N, N-
dimethylformamide: perspectives from experimental toxicology
N,N-Dimethylformamide (DMF) is globally used as an organic solvent in
the production of synthetic leather and resins because of its low
volatility, making it an attractive industrial material. Despite its
excellent property as a chemical solvent, utilisation of DMF is
somewhat controversial nowadays due to its hazardous effects on
exposed workers in work places. Many toxification cases are being
reported globally and the number of cases of liver damage is still
increasing in developing countries. On account of this, a series of
epidemiological surveys are being conducted to understand the degrees
of liver damage caused by DMF exposure. Furthermore, many
investigations have been performed to clarify the mechanism of DMF-
induced liver toxicity using both human and experimental animal
models. In this review, the authors summarise the current
occupational cases reported on liver damage from workers exposed to
DMF in industrial work places and the research results that account
for DMF-induced liver failure and possible carcinogenesis. The
findings reviewed here show the synergistic toxicity of DMF exposure
with other toxicants, which might occur through complicated but
distinct mechanisms, which may extend our knowledge for establishing
risk assessments of DMF exposure in industrial work places.
Authors: Kim, Tae Hyun; Kim, Sang Geon
Full Source: SH & W 2011, 2(2), 97-104 (English)


~dPublic Health
~tA study on the correlation and concentration in Volatile Organic
Compounds(Benzene, Toluene, Xylene) levels according to
indoor/outdoor and type of residents' house in industrial area
This study characterised residents in industrial areas and the
factors affecting exposure to the volatile organic compounds(VOCs)
including benzene, toluene and xylene). In addition, the authors
assessed exposure levels according to house-type, and whether
residents were indoors or outdoors. This research was designed to
assess the differences in exposure levels to indoor, outdoor and
personal VOCs in a case group and a control group across all areas,
as well as in each different area, from May to October 2007, in 110
residents of the G, Y and H industrial areas of the Jun-nam province.
The geometric mean-levels of airborne benzene for the case group 1.31
part per billion(ppb) indoor, 1.29 ppb outdoor, and 1.32 ppb for
personal exposure were significantly higher than for the control
group 0.99, 0.87 and 0.57 ppb, respectively. The geometric mean level
for toluene personal exposure across the G, Y and H areas was 5.70
ppb for the case group and 6.31 ppb for the control group. While the
outdoor level was 4.27 ppb for the case group and 5.06 ppb for the
control group, The indoor level for the case group was 4.78 ppb,
similar to that of the control group 4.69 ppb. The geometric mean
levels for airborne xylene across the G, Y and H areas were 0.16
ppb(outdoor), 0.12 ppb(personal exposure) and 0.10 ppb(indoor) for
the case group, and for the control group were 0.17(personal
exposure) and 0.09 ppb(indoor and outdoor). The indoor/outdoor(I/O)
ratio for case group is 1.19, while that of the control group is
1.15, indicating that the indoor level was higher than the outdoor
level. The interrelationship differences among the three different
types of levels in the air in the G, Y and H areas are statistically
significant, except for the difference between the indoor and outdoor
figures for xylene. In terms of the different types of houses and
energy type used, the geometric mean level for airborne benzene,
toluene and xylene for houses were 1.61, 5.39 and 0.12 ppb,
respectively while the figures for flats were 0.67, 3.32 and 0.05
ppb, respectively. Outdoors, the levels of benzene and toluene in
flats were 0.71 and 2.62 ppb, respectively and 1.58 and 5.35 ppb in
houses. For personal exposure, the house levels of benzene, toluene
and xylene were all higher than for flats. Houses using oil for
heating have significantly higher levels than flats, which use gas
for heating.
Authors: Lee, Che-Won; Jeon, Hye-Li; Hong, Eun-Ju; Yu, Seung-Do; Kim,
Dae-Sun; Son, Bu-Soon
Full Source: Hangug Hwangyeong Bogeon Haghoeji 2010, 36(5), 351-359

~dPublic Health
~tTemporal trends in serum concentrations of polychlorinated dioxins,
furans, and PCBs among adult women living in Chapaevsk, Russia: a
longitudinal study from 2000 to 2009
The present study assessed the temporal trend in serum concentrations
of polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls
(PCBs) among residents of a Russian town where levels of these
chemicals are elevated due to prior industrial activity. Two serum
samples were collected from eight adult women (in 2000 and 2009), and
analysed with gas chromatography-high-resolution mass spectrometry.
The results demonstrated that the average total toxic equivalency
(TEQ) decreased by 30% (from 36 to 25 pg/g lipid), and the average
sum of PCB congeners decreased by 19% (from 291 to 211 ng/g lipid).
Total TEQs decreased for seven of the eight women, and the sum of
PCBs decreased for six of eight women. During this nine year period,
larger decreases in serum TEQs and PCBs were found in women with
greater increases in body mass index. The authors concluded that the
findings from this study provide suggestive evidence that average
serum concentrations of dioxins, furans, and PCBs are decreasing over
time among residents of this town.
Authors: Humblet, Olivier; Sergeyev, Oleg; Altshul, Larisa; Korrick,
Susan A.; Williams, Paige L.; Emond, Claude; Birnbaum, Linda S.;
Burns, Jane S.; Lee, Mary M.; Revich, Boris; Shelepchikov, Andrey;
Feshin, Denis; Hauser, Russ
Full Source: Environmental Health (London, United Kingdom) 2011, 10,
62 (English)

~dPublic Health
~tPhysical chemical characteristics of power plant emissions and
their impact on human health
This study examined the workplace dusts generated in power plants,
with particular reference to thermal power of Mintia - Deva. In order
to determine the chemical composition of powder, structural analysis
was used by corroborating data obtained by elemental analysis
performed by two methods: atomic absorption spectrometry and SEM-
EDAX. Dust collected from various locations in power plant contained
more than 25% SiO2, 4% Al2O3 10% Fe2O3. The impact of these particles
on health workers in these different workplaces was assessed by
specific biochemical and haematological tests. The authors concluded
that the level of cytokines was proposed as an indicator for the
inflammatory processes associated with exposure to occupational
Authors: Raducanu, Alice; Codorean, Eleonora; Grigoriu, Constantin;
Meghea, Aurelia
Full Source: Scientific Bulletin - University "Politehnica" of
Bucharest, Series B: Chemistry and Materials Science 2011, 73(2),
115-122 (English)

~dPublic Health
~tOral bioaccessibility of trace metals in household dust: a review
Because household dust is a heterogeneous assortment of particles
derived from a multitude of diverse sources, concentrations of
toxicants, like trace metals, vary widely among sample populations.
For risk assessment purposes, the bioaccessibility of a trace metal,
or its degree of solubilisation in the human lung or digestive
environment, provides a better metric of its potential health impact
than its total concentration. In this study, the author reviews the
relatively little direct information that exists on the in vitro oral
bioaccessibilities of metals in household dust. Data and mechanisms
from studies involving better characterised geosolids, like soil and
street dust, or metal-rich components thereof, such as paints, are
also extrapolated to the household setting, although use of these
solids as surrogates of household dust is not recommended. The
bioaccessibility of a given metal is highly variable in the household
setting; for instance, reported accessibilities of Pb in fluids that
mimic the human stomach range from 25 to 80%, and accessibility is
usually, but not always, reduced when conditions are altered to mimic
the intestine. While part of this variation reflects the inherent
heterogeneity of samples arising from local to regional differences
in geological, industrial emissions, and domestic (and cultural)
practices, considerable variation results from the precise means by
which bioaccessibility is detected in vitro. The author recommended
that the effects of physicochemical variables, and in particular, the
solid to fluid ratio and the pH of the stomach phase, are studied
systematically such that appropriate algorithms or corrections may be
factored into measures of bioaccessibility obtained under
operationally defined default conditions.
Author: Turner, Andrew
Full Source: Environmental Geochemistry and Health 2011, 33(4), 331-
341 (English)

~dPublic Health
~tEnvironmental pollutants and male reproductive disorders:
phthalates at the heart of the debate
Two major functions are assumed by the testis: the production of male
gametes (i.e. spermatozoa) and the production of steroid hormones.
Those 2 functions are established during foetal life and are
essentials for the adult fertility and the masculinisation of the
internal tract and genitalia. For many years, the laboratory has been
interested in the ontogeny of those 2 functions in rodents and since
2003, in collaboration with Gynecological and Obstetrics service of
Professor R. Frydman in A. Beclere hospital, the authors have studied
them in the human. This study aimed to improve the global knowledge
of the human foetal testis development by using both experimental
data and the literature. The authors then focused on the different
defects that can occur during the foetal testis development. Indeed,
male reproductive abnormalities have been steadily increasing since
the last decades and are thought to be related to the concomitant
increase of the concentration of contaminants and particularly of
endocrine disruptors in the environment. Thus, the authors decided to
study the effect of endocrine disruptors on human foetal testis, and
more particularly the effect of phthalates, by using an organ culture
system developed for human. In contrast to the data obtained in rat,
mono (ethylhexyl) phthalate (MEHP), an active metabolite of the most
widespread phthalate in the environment, does not disturb the
steroidogenic function. On the other hand, it has a negative effect
on the male germ cell number. The authors concluded that this study
is the first experimental demonstration of a negative effect of
phthalates directly on human reproductive functions. Using a
molecular approach, the aim is now to understand the mechanisms of
phthalate's action.
Authors: Rouiller-Fabre, Virginie; Muczynski, Vincent; Lecureuil,
Charlotte; Livera, Gabriel; Moison, Delphine; Frydman, Rene; Habert,
Full Source: Cahiers de Nutrition et de Dietetique 2011, 46(2), 75-81


~tPreventing loss of containment through a systematic assessment of
hazards, consequences, and risks
A review of Loss of containment (LOC) of toxic chemicals, flammable
chemicals, and/or energy from vessels, pipes, or other equipment can
potentially lead to consequences that can range from minor to
catastrophic. A fundamental understanding and detailed assessment of
the hazards is an important first step, which may be much more
involved than just reviewing or communicating material safety data
sheets. Next, a complete range of failure scenarios should be
analysed in a systematic manner, including quality and quantity
methods, to develop information on potential consequences. With an
understanding of hazards and the consequences of LOC events, and
ideally some good process data, a process hazards analysis team,
using a semi-quantitative risk analysis can evaluate the adequacy of
systems and the layers of protection necessary for preventing and
mitigating loss of containment events. This paper will share some of
the typical approaches that have worked well within the industry in
general and DuPont in particular.
Authors: Dharmavaram, S.; Klein, James A.
Full Source: AIChE Spring Meeting & 6th Global Congress on Process
Safety, Conference Proceedings, San Antonio, TX, United States, Mar.
21-25, 2010 [computer optical disk] 2010, dharma2/1-dharma2/18 (Eng)

~tChallenges in developing and implementing safety risk tolerance
A review of risk quantification can help in understanding and
managing risk. Establishing quantitative risk criteria can be a key
component to risk decision-making and many companies use such
criteria, either formally or informally. The Centre for Chemical
Process Safety issued its guidance on developing quantitative safety
risk criteria in 2009 – (CCPS Guidelines for Developing Quantitative
Safety Risk Tolerance Criteria). This paper addresses some of the
more common challenges that users may face in developing and
implementing safety risk tolerance criteria as they apply the
Author: Frank, Walt
Full Source: AIChE Spring Meeting & 6th Global Congress on Process
Safety, Conference Proceedings, San Antonio, TX, United States, Mar.
21-25, 2010 [computer optical disk] 2010, frank1/1-frank1/16 (Eng)

~tProcess safety and chemical security-the need for company specific
risk criteria
A review of risk criteria are an essential component in both quality
and quantity risk analysis methods, and are used to identify where
additional investment in people, time, and capital are warranted to
manage risk to an acceptable level. Most global
chemical/petrochemical companies have defined risk criteria for
safety and security that align with international regulations and
guidelines, and /or the risk appetite (or "acceptance criteria") of
the company as a whole. The benefit of defined risk criteria is that
these companies can evaluate operations consistently and invest
resources where truly justified. If companies have not taken a
holistic approach to risk management by developing such criteria,
they lack a consistent basis for making risk decisions. This often
results in safety and security assessments and management decisions
that are made with ad-hoc risk criteria, ultimately leading to poor
risk management decisions. This may include overly conservative tests
of risk leading to unjustified spending on safety or security
upgrades; or acceptance of risks leading to non-uniform company
exposures. This paper provides an overview of how a company can
develop safety and security risk criteria. It includes a review of
accepted international guidelines, differences in safety and security
analyses, and a process for ensuring risk criteria are in alignment
with that of the organisation.
Author: Fuller, Brad A.
Full Source: AIChE Spring Meeting & 6th Global Congress on Process
Safety, Conference Proceedings, San Antonio, TX, United States, Mar.
21-25, 2010 [computer optical disk]2010, fuller1/1-fuller1/13 (Eng)

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