The potential exists for human exposure to polychlorinated biphenyls (PCBs) and other contaminants originating from abandoned Mid-Canada Radar Line (MCRL) sites in sub-arctic Canada. We examined patterns of differences with respect to body burden of organochlorines (lipid-adjusted) between residents of the Ontario First Nations of Fort Albany (the site of MCRL Site 050) and Kashechewan (no radar base) and Hamilton (an industrial, southern Ontario community) to assess whether the presence of Site 050 influenced organochlorine body burden with respect to the people of Fort Albany. PCBs (Aroclor 1260 and summation operator14 PCBs congeners [CBs]) and DDE in the plasma of Fort Albany and Kashechewan subjects were elevated relative to Hamilton participants. PCB and DDE-plasma levels in First Nation women were of comparable magnitude to those reported for Inuit women living in the west/central Northwest Territories. Significantly lower DDE/DDT ratios observed for Fort Albany indicates exposure to higher levels of DDT compared to Kashechewan. The probable source of DDT exposure for Fort Albany people is the DDT-contaminated soil surrounding buildings of Site 050. The results of the correspondence analysis (CA) indicated that people from Hamilton had relatively higher pesticides and lower CB body burdens, while people from Fort Albany and Kashechewan exhibited relatively higher CBs and lower pesticide levels (CA-1). The separation of Fort Albany and Kashechewan from Hamilton was also clear using questionnaire data (i.e., plotting dietary principal component [PC]-1 scores against PC-2); PC-1 was correlated with the consumption of a traditional diet. Separation of Kashechewan and Albany residents occurred because the people of Kashechewan ate more traditional meats and consumed shorebirds. Only one significant relationship was found between PC analysis and contaminant loadings; PC-1 versus CA-3 for Kashechewan. The presence of Site 050 on Anderson Island appears to have influenced organochlorine body burden of the people of Fort Albany. ANCOVA results revealed that it was not activity on Anderson Island that was important, but activity on Site 050 was the influential variable. When these results are considered with the DDE/DDT ratio data and the CB 187 results (Fort Albany and Kashechewan residents differed significantly), the findings are suggestive that Site 050 did influence organochlorine body burden of people from Fort Albany.
Department of Environmental Medicine, Institute of Public Health (C.A.G.T., L.I.R., C.D., P.G., F.N., T.K.J.), and Institute of Sports Science and Clinical Biomechanics (A.G., M.R.-L., L.B.A.), University of Southern Denmark, 5000 Odense C, Denmark; and Department of Biostatistics (K.D.S., T.S.), University of Copenhagen, 1353 Copenhagen, Denmark.
Our objective was to explore whether childhood exposure to perfluorinated and polyfluorinated compounds (PFCs), widely used stain- and grease-repellent chemicals, is associated with adiposity and markers of glycemic control.
Body mass index, skinfold thickness, waist circumference, leptin, adiponectin, insulin, glucose, and triglyceride concentrations were assessed in 8- to 10-year-old children in 1997 in a subset of the European Youth Heart Study, Danish component. Plasma PFC concentrations were available from 499 children. Linear regression models were performed to determine the association between PFC exposure and indicators of adiposity and markers of glycemic control.
There was no association between PFC exposures and adiposity or markers of glycemic control in normal-weight children. Among overweight children, an increase of 10 ng perfluorooctane sulfonic acid/mL plasma was associated with 16.2% (95% confidence interval [CI], 5.2%-28.3%) higher insulin concentration, 12.0% (95% CI, 2.4%-22.4%) higher ß-cell activity, 17.6% (95% CI, 5.8%-30.8%) higher insulin resistance, and 8.6% (95% CI, 1.2%-16.5%) higher triglyceride concentrations, and an increase of 10 ng perfluorooctanoic acid/mL plasma was associated with 71.6% (95% CI, 2.4%-187.5%) higher insulin concentration, 67.5% (95% CI, 5.5%-166.0%) higher ß-cell function, 73.9% (95% CI, 0.2%-202.0%) higher insulin resistance, and 76.2% (95% CI, 22.8%-153.0%) higher triglyceride concentrations.
Increased PFC exposure in overweight 8- to 10-year-old children was associated with higher insulin and triglyceride concentrations. Chance findings may explain some of our results, and due to the cross-sectional design, reverse causation cannot be excluded. The findings therefore need to be confirmed in longitudinal studies.
A trace analytical method is presented for the analysis of hydroxylated polychlorinated biphenyl metabolites (HO-PCBs) and pentachlorophenol (PCP) in human plasma. The described methodology is a modification of a previously validated method used for PCB and organochlorine pesticide analysis. The modified method enables the combined analysis of phenolic and neutral halogenated compounds. A tandem Florisil column is used for separating the HO-PCBs and PCP from the neutral fraction, instead of the more common chemical partitioning. In the same step the neutral fraction is purified for GC analysis. The extraction of the HO-PCBs and PCP was found to be highly dependent on sufficient acidification of the sample and the polarity of the extracting solvent. Analysis of plasma samples gave recovery rates for (13)C(6)-PCP and (13)C(12)-4-HO-CB 187 of 64 and 72%, respectively. The limit of detection ranged between 2-20 pg g(-1) plasma for the HO-PCBs and 5 pg g(-1) plasma for PCP. No matrix interferences were observed in the chromatograms. In plasma samples (n = 15) from the native Chukchi people in Uelen (Russian Arctic), a population with high PCB exposure, the median ratio of sum HO-PCBs to sum PCBs was as high as 0.4 and the sum HO-PCBs and PCBs were significantly correlated (r(2) > 0.7, p
In this study, we identified the main hydroxylated polychlorinated biphenyls (OH-PCBs) and other chlorinated phenolic compounds and we determined their relative concentrations in whole blood from 13 male and 17 female Inuit from northern Quebec, Canada, and from a pooled whole blood sample from southern Quebec. We also determined concentrations of polychlorinated biphenyls (PCBs). Total OH-PCB concentrations were variable among the Inuit samples, ranging over 2 orders of magnitude (0.117-11.6 ng/g whole blood wet weight). These concentrations were equal to and up to 70 times those found for the southern Quebec pooled whole blood sample. Geometric mean concentrations of total OH-PCBs were 1.73 and 1.01 ng/g whole blood for Inuit men and women, respectively, and 0.161 ng/g whole blood for the southern population pool. There are limited data available for comparison, but the levels of OH-PCBs in Inuit are higher than those previously reported in the literature for other populations. There was a significant correlation (p
OBJECTIVES: Exposure to persistent organohalogen pollutants was suggested to impair male reproductive function. A gene-environment interaction has been proposed. No genes modifying the effect of persistent organohalogen pollutants on reproductive organs have yet been identified. We aimed to investigate whether the CAG and GGN polymorphisms in the androgen receptor gene modify the effect of persistent organohalogen pollutant exposure on human sperm characteristics. METHODS: Semen and blood from 680 men [mean (SD) age 34 (10) years] from Greenland, Sweden, Warsaw (Poland) and Kharkiv (Ukraine) were collected. Persistent organohalogen pollutant exposure was assessed by measuring serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and dichlorodiphenyl dichloroethene (p,p'-DDE). Semen characteristics (volume, sperm concentration, total count, proportion of progressively motile and morphology) and DNA fragmentation index (DFI) were determined. CAG and GGN repeat lengths were determined by direct sequencing of leukocyte DNA. RESULTS: A statistically significant interaction was found between the CB-153 group and CAG repeat category in relation to sperm concentration and total sperm count (P=0.03 and 0.01, respectively). For p,p'-DDE, in the European cohorts a significant interaction was found in relation to DFI (P=0.01). For CAG
Cadmium (Cd), a nonessential toxic metal present in the environment, accumulates in the organs of herbivorous mammals which typically are consumed by Aboriginal populations. The relative contribution of this potential exposure source to concentrations of blood Cd was investigated in 1429 participants (age >7 years) residing in the nine Cree First Nations communities of Eeyou Istchee, northern Quebec, Canada. Analysis of variance identified significant Cd concentration differences between communities, sex, and age groups, although these were complicated by significant 2-way interactions. The percentage of participants with Cd concentrations within the adopted health-based guideline categories of 'acceptable', 'concern' and 'action' pertaining to kidney damage was 56.2%, 38.3%, and 5.5%, respectively. Partial correlations (controlling for age as a continuous variable) did not show a significant association between consumption of traditional foods and Cd concentrations (r = 0.014, df = 105, p = 0.883). A significant and positive partial correlation (r = 0.390, df = 105, p
We are daily exposed to many different environmental contaminants. Mixtures of these contaminants could act together to induce more pronounced effects than the sum of the individual contaminants. To evaluate the effects of such mixtures, it is of importance to assess the co-variance amongst the contaminants. Thirty-seven environmental contaminants representing different classes were measured in blood samples from 1016 individuals aged 70 years. Hierarchical cluster analysis and principal component analysis were used to assess the co-variation among the contaminants. Within each identified cluster, possible marker contaminants were sought for. We validated our findings using data from the National Health and Nutrition Examination Survey (NHANES) 2003-2004 study. Two large clusters could be identified, one representing low/medium chlorinated polychlorinated biphenyls (PCBs) (=6 chlorine atoms), as well as two pesticides and one representing medium/high chlorinated PCBs (=6 chlorine atoms). PCBs 118 and 153 could be used as markers for the low/medium chlorinated cluster and PCBs 170 and 209 could be used as markers for the medium/high chlorinated cluster. This pattern was similar to data from the NHANES study. Apart from the PCBs, little co-variation was seen among the contaminants. Thus, a large number of chemicals have to be measured to adequately identify mixtures of environmental contaminants.
Recent studies have shown that the detrimental effects of anthropogenic pollutants may be worse if organisms are exposed to natural stress. In this study, we examined whether negative effects of organochlorines (OCs) could be influenced by parasites. In two breeding seasons, we administered an anti-helminthic drug to groups of breeding glaucous gulls (Larus hyperboreus), whereas control groups were placebo treated. In all birds, blood residues of the most important OCs in the study population (hexachlorobenzene, oxychlordane, p,p'-dichlorodiphenyldichloroethylene and polychlorinated biphenyl), were measured. The relationships between OCs and fitness components (i.e. nesting success and return rate between breeding seasons) were then compared between the birds receiving anti-parasite treatment and the controls. Among untreated males, higher blood residues of OCs were associated with lowered nesting success, while in males receiving anti-parasite treatment, there was no detrimental effect of OCs on fitness. Return rate was not affected by treatment or OCs. Our findings suggest that parasites may be an important factor in triggering reproductive effects of such pollutants, and that relatively low levels of OCs may have serious reproductive consequences in natural populations when stress from other sources is high.
The mechanisms involved in thyroid homeostasis are complex, and perfluoroalkyl substances (PFASs) have been indicated to interfere at several levels in this endocrine system. Disruption of the maternal thyroid homeostasis during early pregnancy is of particular concern, where subclinical changes in maternal thyroid hormones (THs) may affect embryonic and foetal development. The present study investigated associations between THs, thyroid binding proteins (TH-BPs) and PFAS concentrations in pregnant women from Northern Norway. Women participating in The Northern Norway Mother-and-Child contaminant Cohort Study (MISA) donated a blood sample at three visits related to their pregnancy and postpartum period (during the second trimester, 3 days and 6 weeks after delivery) in the period 2007-2009. Participants were assigned to quartiles according to PFAS concentrations during the second trimester and mixed effects linear models were used to investigate potential associations between PFASs and repeated measurements of THs, TH-BPs, thyroxin binding capacity and thyroid peroxidase antibodies (anti-TPOs). Women within the highest perfluorooctane sulfonate (PFOS) quartile had 24% higher mean concentrations of thyroid stimulating hormone (TSH) compared to the first quartile at all sampling points. Women within the highest quartiles of perfluorodecanoate (PFDA) had 4% lower mean concentrations of triiodothyronine (T3) and women within the highest quartile of perfluoroundecanoate (PFUnDA) had 3% lower mean concentrations of free triiodothyronine (FT3). Further, the difference in concentrations and the changes between three time points were the same for the PFAS quartiles. Thyroxin binding capacity was associated with all the THs and TH-BPs, and was selected as a holistic adjustment for individual changes in TH homeostasis during pregnancy. Finally, adjusting for maternal iodine status did not influence the model predictions. Findings in the present study suggest modifications of TH homeostasis by PFASs in a background exposed maternal population. The variation in levels of THs between PFAS quartiles was within normal reference ranges and may not be of clinical significance in the pregnant woman. However, subtle individual changes in maternal THs may have significant consequences for foetal health.
The aim of this study was to evaluate hexachlorocyclohexane (HCH) exposure in children living in nine hot spots in four Mexican states. We analyzed HCH (a, ß, and ?-isomers) in blood using gas chromatography/mass spectrometry. HCH exposure level in 261 children was assessed and approximately 75 % of the children studied had detectable levels of HCH. These levels ranged from 188 to 40,096.7 ng/g lipid. The highest mean levels were found in Lacanja (5,446.9 ng/g lipid), an indigenous community in Chiapas, Mexico. Our data indicate high exposure to HCH in children living in these communities.