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Pyrethroid pesticides are commonly used in tropical regions such as the Caribbean as household insecticides, pet sprays, and where malaria is endemic, impregnated into mosquito-repellent nets. Of particular concern is exposure during pregnancy, as these compounds have the potential to cross the placental barrier and interfere with fetal development, as was shown in limited animal studies. The objective of this study was to evaluate exposure to pyrethroids to pregnant women residing in 10 English-speaking Caribbean countries. Pyrethroid exposures were determined by analyzing five pyrethroid metabolites in urine samples from 295 pregnant women: cis-DBCA, cis-DCCA, trans-DCCA, 3-PBA, and 4-F-3-PBA. Pyrethroid metabolite concentrations in Caribbean pregnant women were generally higher in the 10 Caribbean countries than levels reported for Canadian and U.S. women. In Antigua & Barbuda and Jamaica participants the geometric mean concentrations of cis-DBCA was significantly higher than in the other nine countries together (p<0.0001 and <0.0012 respectively). For cis- and trans-DCCA, only Antigua & Barbuda women differed significantly from participants of the other nine Caribbean countries (p<0.0001). Urinary 4-F-3-PBA and 3-PBA levels were significantly higher in Antigua & Barbuda (p<0.0028 and p<0.0001 respectively) as well as in Grenada (p<0.0001 and p<0.007 respectively). These results indicate extensive use of pyrethroid compounds such as permethrin and cypermethrin in Caribbean households. In Antigua & Barbuda, the data reveals a greater use of deltamethrin. This study underscores the need for Caribbean public health authorities to encourage their populations, and in particular pregnant women, to utilize this class of pesticides more judiciously given the potentially adverse effects of exposure on fetuses and infants., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The Inuit population of Nunavik (Canada) is exposed to immunotoxic organochlorines (OCs) mainly through the consumption of fish and marine mammal fat. We investigated the effect of perinatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) on the incidence of acute infections in Inuit infants. We reviewed the medical charts of a cohort of 199 Inuit infants during the first 12 months of life and evaluated the incidence rates of upper and lower respiratory tract infections (URTI and LRTIs, respectively), otitis media, and gastrointestinal (GI) infections. Maternal plasma during delivery and infant plasma at 7 months of age were sampled and assayed for PCBs and DDE. Compared to rates for infants in the first quartile of exposure to PCBs (least exposed), adjusted rate ratios for infants in higher quartiles ranged between 1.09 and 1.32 for URTIs, 0.99 and 1.39 for otitis, 1.52 and 1.89 for GI infections, and 1.16 and 1.68 for LRTIs during the first 6 months of follow-up. For all infections combined, the rate ratios ranged from 1.17 to 1.27. The effect size was similar for DDE exposure but was lower for the full 12-month follow-up. Globally, most rate ratios were > 1.0, but few were statistically significant (p < 0.05). No association was found when postnatal exposure was considered. These results show a possible association between prenatal exposure to OCs and acute infections early in life in this Inuit population.

During the past 20 years a number of studies have found neurological and immunological effects in the developing fetus and infants exposed to background or only slightly elevated levels of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs). To address concerns arising from possible increased human exposure in the Arctic and possible effects of POPs, all circumpolar countries agreed in 1994 to monitoring of specific human tissues for contaminants in the Arctic under the Arctic Monitoring and Assessment Program (AMAP). Mothers in eight circumpolar countries contributed blood samples that were analysed at a single laboratory for 14 PCB congeners (IUPAC No. 28, 52, 99, 105, 118, 128, 138, 153, 156, 170, 180, 183, 187) and 13 organochlorine pesticides (aldrin, beta-hexachlorocyclohexane (beta-HCH), dichlordiphenyltrichloroethane (p,p'-DDT), diphenyldichloroethylene (p,p'-DDE), dieldrin, heptachlorepoxide, hexachlorobenzene (HCB), mirex, and the chlordane derivatives alpha-chlordane, gamma-chlordane, cis-nonachlor, oxychlordane and trans-nonachlor). Inuit mothers from Greenland and Canada have significantly higher levels of oxychlordane, transnonachlor and mirex than mothers from Norway, Sweden, Iceland and Russia. Inuit mothers from Greenland also have significantly higher levels of these contaminants than Inuit mothers from Canada and Alaska. These differences among Inuit groups may represent regional dietary preferences or different contaminant deposition patterns across the Arctic. Levels of PCBs are also elevated among some arctic populations due to their consumption of marine mammals and are in the range where subtle effects on learning and the immune system have been reported. The Russian mothers who consume mainly food imported from southern Russia have elevated levels of DDT, DDE, beta-HCH and a higher proportion of lower chlorinated PCB congeners. This study has allowed an assessment of the variation of contaminants such as PCBs and various organochlorine pesticides (DDT, chlordane, etc.) in human populations around the circumpolar north.

A cross-sectional study was conducted to evaluate nonoccupational biological exposure to 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) compounds and to identify the main factors associated with such exposure in a malaria endemic region in Mexico. Capillary gas column chromatography was used to determine levels of p,p'-DDT and its metabolites in plasma. The mean age of the 144 male participants was 28 yr. Mean p,p'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene) and p,p'-DDT levels were 203.5 microg/l and 67.4 microg/l, respectively. Those whose houses had been sprayed for malaria control had much higher p,p'-DDE levels (p < 0.001). High levels of chlorinated pesticides were found despite being banned in Mexico for agricultural and public health use. Findings demonstrate the role of antimalarial campaigns as a major contributing factor for high DDT plasma levels.

Remote coastal populations that rely on seafood for subsistence often receive unusually high doses of organochlorines and methyl mercury. Immunosuppression resulting from prenatal exposure to organochlorines has been reported in wildlife species and humans. In this study, we assessed lymphocyte activation and associated cytokine secretion in 47 newborns from a remote maritime population living on the Mid and Lower North Shore regions of the St. Lawrence River (Québec, Canada; subsistence fishing group) and 65 newborns from nearby urban settings (reference group). Cord blood samples were collected for organochlorine and mercury analyses and also to isolate cord blood mononuclear cells (CBMCs) for the in vitro assessment of cytokine production and expression of surface markers after mitogenic stimulation (CD4(+)CD45RO(+), CD8(+)CD45RO(+), CD3(+)CD25(+), and CD8(+)HLA-DR(+)). Blood mercury and plasma concentrations of polychlorinated biphenyls (PCBs), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p'-DDE), and hexachlorobenzene (HCB) were significantly higher in the subsistence fishing group than in the reference group (p < 0.001). No difference was observed between the two groups regarding subsets of lymphocytes showing markers of activation. In vitro secretion of cytokines by CBMCs after mitogenic stimulation was lower in the subsistence fishing group than in the reference group (p < 0.05). Moreover, we found an inverse correlation between tumor necrosis factor-alpha (TNF-alpha) secretion and plasma PCB, p,p'-DDE, and HCB concentrations (p < 0.05). Our data support a negative association between TNF-alpha secretion by CBMCs and prenatal organochlorine exposure. If the relationship between organochlorine and TNF-alpha secretion is causal, it would suggest a role for this important proinflammatory cytokine in mediating organochlorine-induced immunotoxicity in infants developmentally exposed to these compounds.

Inuit inhabitants of Nunavik (northern Québec, Canada) consume great quantities of marine food and are therefore exposed to high doses of food chain contaminants. In this study, we report the time trends of persistent organic pollutants, mercury, and lead in umbilical cord blood of infants from three communities of the east coast of Hudson Bay in Nunavik. We analyzed 251 cord blood samples collected from 1994 through 2001 for polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (DDT), dichlorodiphenyl dichloroethylene (DDE), hexachlorobenzene (HCB), chlordanes, lead, and mercury. Using an exponential model, we found strongly significant decreasing trends for PCBs (7.9% per year, p < 0.001), DDE (9.1% per year, p < 0.001), DDT (8.2% per year, p < 0.001), and HCB (6.6% per year, p < 0.01). No significant trends were detected for chlordanes. A significant reduction of lead and mercury concentrations was found, but there was no clear linear or exponential trend. The decreases observed could be explained by a decrease in food contamination, by changes in dietary habits, or, most likely, by a combination of both.

This study describes the time trends of organochlorines [OCs; 14 polychlorinated biphenyls (PCBs) and 11 chlorinated pesticides] in umbilical cord plasma of newborns in a remote Canadian coastal population. We analyzed 408 cord blood samples collected between 1993 and 2000 for PCBs, chlordanes, dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyltrichloroethylene (DDE), hexachlorobenzene (HCB), and n-3 fatty acids. We also gathered information on the mothers (age, past and present residence, ethnic group, use of tobacco during pregnancy, and breast-feeding during previous pregnancies). From 1993 to 2000, mean concentrations of PCBs, chlordanes, DDT/DDE, and HCB in cord blood decreased by 63%, 25%, 66%, and 69%, respectively (p < 0.0001). Multiple regression analysis with the year of birth as the main independent variable yielded a strong significant exponential decrease for all contaminants (in all age and ethnic groups). We detected no monthly or seasonal pattern. We used n-3 fatty acids concentration as a surrogate of maternal fish consumption. Fish consumption declined only slightly between 1993 and 2000, but this decrease did not contribute significantly to the reduction of OCs. These results show that prenatal exposure to persistent OCs has declined significantly between 1993 and 2000 in this population.

Environmental pollutants can act as endocrine modulators. In this study, we examined whether weight loss-induced changes in plasma organochlorine compounds (OC) were associated with those in plasma insulin levels. Fasting insulin and the area under the curve (AUC) of insulin after a 75-g oral glucose load, plasma levels of 1 commercial polychlorinated biphenyl (PCB) mixture (Aroclor 1260), 1 PCB congener (PCB 153), and 3 pesticides (2,2'-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), beta-hexachlorocyclohexane (beta-HCH), and hexachlorobenzene (HCB)) were measured before and after a 15-week weight loss program induced by a caloric restriction in a sample of obese men and women. Both genders showed a similar reduction in body weight (approximately 11 kg) in response to treatment, although men lost significantly more fat mass than women (mean +/- SD 9.4 +/- 4.1 v 5.9 +/- 5 kg, respectively, P <.05). Fasting insulin and AUC of insulin significantly decreased in men and women after the treatment. In response to weight loss, a significant increase in OC was observed in both genders, and this effect was more pronounced in men. The greater the increase in plasma OC levels, the greater the reduction in fasting insulin was in response to weight loss in men (-.49 < r < -.59, P <.05), but not in women (-.22 < r <.01, not significant [NS]). In both genders, no relationship was observed between changes in plasma OC levels and changes in AUC of insulin (-.41 < r < -.08, NS). In men, relationships between changes in plasma HCB, Aroclor 1260, and PCB-153 concentrations and those in fasting insulin levels in response to weight loss remained significantly correlated after correction for fat mass loss (-.46 < partial r < -.51, P values ranging from.05 to.07). These results suggest that weight loss-induced increase in plasma pollutant levels tends to be independently associated with the reduction of fasting insulin levels in men, but not in women. Further studies are needed to verify whether these findings are causally related., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

The Inuit population residing in Nunavik (northern Québec, Canada) relies on species from the marine food web for subsistence and is therefore exposed to high doses of environmental contaminants such as polychlorinated biphenyls and methylmercury and to a lesser extent lead. In view of the neurotoxic properties of these substances following developmental exposure, we initiated a study on infant development in this remote coastal population. Here we report the magnitude of prenatal exposure to these contaminants and to selective nutrients in Inuit mothers and their newborns who were recruited on the Hudson Bay coast. We conducted interviews during the women's pregnancies and at 1 and 11 months postpartum and collected biological samples for mercury, lead, polychlorinated biphenyls (PCBs), and chlorinated pesticides analyses as well as selenium and N-3 polyunsaturated fatty acids (n3-PUFA). Cord blood, maternal blood, and maternal hair mercury concentrations averaged 18.5 microg/L, 10.4 microg/L, and 3.7 microg/g, respectively, and are similar to those found in the Faroe Islands but lower than those documented in the Seychelles Islands and New Zealand cohorts. Concentrations of PCB congener 153 averaged 86.9, 105.3, and 131.6 microg/kg (lipids) in cord plasma, maternal plasma, and maternal milk, respectively; prenatal exposure to PCBs in the Nunavik cohort is similar to that reported in the Dutch but much lower than those in other Arctic cohorts. Levels of n3-PUFA in plasma phospholipids and selenium in blood are relatively high. The relatively low correlations observed between organochlorine and methylmercury concentrations may make it easier to identify the specific developmental deficits attributable to each toxicant. Similarly, the weak correlations noted between environmental contaminants and nutrients will facilitate the documentation of possible protective effects afforded by either n3-PUFA or selenium against neurotoxic contaminants.

High organochlorine concentrations have been found among the Inuit in eastern Canada and in Greenland. The present study was undertaken to assess the exposure to organochlorines in relation to age, sex, and diet in a general population sample of Inuit from Greenland. Survey data and plasma concentrations of 14 polychlorinated biphenyl (PCB) congeners and 16 pesticides, including 5 toxaphene congeners, were recorded in a random population survey of 408 adult indigenous Greenlanders. In a two-stage design, the survey response rate was 66%, and 90% of those randomly selected for blood testing participated. This was equivalent to an overall response rate of 59%. The median plasma concentration of the sum of PCB congeners was 13.3 microg/L; the lipid-adjusted value was 2109 microg/kg. The PCB concentration was twice as high as among the Inuit of Nunavik, Canada, 25 times higher than in a control group from southern Canada, and several times higher than the values found in European studies. Concentrations were similarly elevated for all PCB congeners and pesticides. The PCB congener pattern was similar to previous observations from the eastern Canadian Arctic and Greenland. Concentrations showed statistically significant positive associations with age, marine diet, and male sex in multiple linear regression analyses. The exceptionally high plasma concentrations of several organochlorines among the Inuit of Greenland are attributed to a lifelong high intake of seafood, in particular marine mammals. Concentrations of PCB adjusted for the consumption of marine food increased until approximately 40 yr of age, which is equivalent to the birth cohorts of the early 1950s. The age pattern indicates that bioaccumulation of PCB started in the 1950s, which is a likely date for the introduction of the compounds into the Arctic environment.

The authors analyzed the relation between lactation history, organochlorine serum levels-in particular, 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE)-and the risk of breast cancer within a subsampe from a larger breast cancer case-control study conducted among women living in Mexico City, Mexico, between 1990 and 1995. From the original study, they selected a random sample of 260 subjects (1:1 case/control ratio). Analysis was restricted to 120 cases and 126 controls who had given birth to at least one child and had complete information on all key variables. Serum DDE levels were higher among cases (mean = 3.84 microg/g lipids, standard deviation = 5.98) than among controls (mean = 2.51 microg/g lipids, standard deviation = 1.97). After adjustment for age, age at menarche, duration of lactation, Quetelet index, and serum DDT levels, serum DDE levels were positively related to the risk of breast cancer (adjusted odds ratio (OR)Q1-Q2 = 1.24, 95% confidence interval (CI): 0.50, 3.06; ORQ1-Q3 = 2.31, 95% CI: 0.92, 5.86; ORQ1-Q4 = 3.81, 95% CI: 1.14, 12.80; test of trend, p = 0.02). The increased risk associated with higher serum DDE levels was more apparent among postmenopausal women (ORQ1-Q4 = 5.26, 95% CI: 0.80, 34.30; test of trend p = 0.03). A longer period of lactation was associated with a slightly decreased risk of breast cancer independently of serum DDE levels (OR = 0.91, 95% CI: 0.85, 0.99 change in risk per 10 months of lactation). Serum DDT level was not related to the risk of breast cancer. The data suggest that high levels of exposure to DDE may increase women's risk of breast cancer, particularly among postmenopausal women.

We investigated whether organochlorine exposure is associated with the incidence of infectious diseases in Inuit infants from Nunavik (Arctic Quebec, Canada). We compiled the number of infectious disease episodes during the first year of life for 98 breast-fed and 73 bottle-fed infants. Concentrations of organochlorines were measured in early breast milk samples and used as surrogates to prenatal exposure levels. Immune system parameters were determined in venous blood samples collected from infants at 3, 7, and 12 months of age. Otitis media was the most frequent disease, with 80. 0% of breast-fed and 81.3% of bottle-fed infants experiencing at least one episode during the first year of life. During the second follow-up period, the risk of otitis media increased with prenatal exposure to p,p'-DDE, hexachlorobenzene, and dieldrin. The relative risk (RR) for 4- to 7-month-old infants in the highest tertile of p, p'-DDE exposure as compared to infants in the lowest tertile was 1. 87 [95% confidence interval (CI), 1.07-3.26]. The RR of otitis media over the entire first year of life also increased with prenatal exposure to p,p'-DDE (RR, 1.52; CI, 1.05-2.22) and hexachlorobenzene (RR, 1.49; CI, 1.10-2.03). Furthermore, the RR of recurrent otitis media ( [Greater/equal to] 3 episodes) increased with prenatal exposure to these compounds. No clinically relevant differences were noted between breast-fed and bottle-fed infants with regard to immunologic parameters, and prenatal organochlorine exposure was not associated with immunologic parameters. We conclude that prenatal organochlorine exposure could be a risk factor for acute otitis media in Inuit infants.

Several organochlorines identified as "hormone mimics" were proposed as possible risk factors for breast cancer. We conducted a case-control study to assess breast cancer risk and disease aggressiveness in relation to plasma concentrations of several organochlorine compounds. Plasma lipid concentrations of 11 chlorinated pesticides and 14 polychlorinated biphenyl congeners were measured in 315 women newly diagnosed with breast cancer, 219 hospital-based controls, and 307 population controls from the Quebec City area (Canada). Concentrations of hormonally active organochlorines or their surrogates were compared between cases and controls as well as between groups of cases defined according to tumor size and axillary-lymph-node involvement. We found similar levels of organochlorines in cases and controls and no relationship between the relative risk of breast cancer and organochlorine exposure. However, the probability of lymph-node invasion among cases increased with exposure to 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene [p,p'-DDE; odds ratio, 2.54; 95% confidence interval (CI), 1.20-5.35; between the highest and the lowest tertiles]. Furthermore, p,p'-DDE exposure was associated with a dose-related increased relative risk of exhibiting both lymph-node involvement and a large tumor. Indeed odds ratio raised to 2.33 (95% CI, 0.94-5.77) for the second tertile relative to the first tertile and reached 3.51 (95% CI, 1.41-8.73) for the third tertile relative to the first tertile. Similar associations were noted with beta-hexachlorocyclohexane, oxychlordane, and transnonachlor. We conclude that exposure to persistent, hormonally active organochlorines during adulthood is not associated with breast cancer risk. The possibility that some organochlorines and especially p,p'-DDE may increase breast cancer aggressiveness deserves further attention.

Organochlorines are persistent lipophilic compounds that accumulate in Inuit people living in circumpolar countries. Organochlorines accumulate as a result of the Inuits' large consumption of sea mammal fat; however, available data are limited to blood lipids, milk fat, and adipose tissue. We report results of organochlorine determination in liver, brain, omental fat, and subcutaneous abdominal fat samples collected from deceased Greenlanders between 1992 and 1994. Eleven chlorinated pesticides and 14 polychlorinated biphenyl congeners were measured in tissue lipid extracts by high-resolution gas chromatography with electron capture detection. Mean concentrations of polychlorinated biphenyls, 2, 2'-bis(4-chlorophenyl)-1,1-dichloroethylene, ss-hexachlorocyclohexane, hexachlorobenzene, mirex, trans-nonachlor, and oxychlordane in adipose tissue samples from Greenlanders were 3-34-fold higher than those measured using the same analytical method in samples from Canadians in Quebec City, Quebec. Brain lipids contained lower concentrations of all organochlorines than lipids extracted from other tissues. Organochlorine residue levels in lipid extracts from liver, omental fat, and subcutaneous abdominal fat samples were similar, with the exception of ss-hexachlorocyclohexane, which reached a greater concentration in liver lipids than in lipids from both adipose tissues (4-fold; p < 0. 05). Comparisons with available international data on adipose tissue levels reveal that the organochlorine body burden in the Inuit population of Greenland is presently among the highest resulting from environmental exposure.

Organochlorine compounds bioaccumulate in fishing and hunting products included in the daily diet of many coastal populations. Prenatal and perinatal exposure to large doses of PCBs and PCDFs was shown to be deleterious on fetal and neonatal development, but information is scarce regarding possible effects of chronic low-dose exposure. This study investigates biomarkers of early effects in newborns from women exposed to organochlorines through the consumption of species from marine food chains, in two remote coastal regions of the province of Quebec (Canada). A CYP1A1-dependent enzyme activity (EROD) and DNA adducts were measured in placenta samples obtained from 30 women living on the Lower-North-Shore of the St. Lawrence River and 22 Inuit women from Nunavik (Arctic Quebec). These biomarkers were also assessed in 30 women from a Quebec urban center (Sept-Iles) as a reference group. Prenatal organochlorine exposure was determined by measuring these compounds in umbilical cord plasma. The amount of bulky polycyclic aromatic hydrocarbon (PAH)-related DNA adducts was significantly greater in the Lower-North-Shore group than in the reference group. Placental EROD activity and the amount of less bulky (OC-related) DNA adducts were significantly higher in the Nunavik group than in the reference group. For both biomarkers, smoking was found to be an important confounding factor. Organochlorine exposure was significantly associated with EROD activity and DNA adduct levels when stratifying for smoking. This study confirms that CYP1A1 enzyme induction and DNA adducts in placental tissue constitute useful biomarkers of early effects induced by environmental exposure to organochlorines., (Copyright 1999 Academic Press.)

We conducted this study to evaluate blood levels of lead, mercury, and organochlorine compounds in newborns in the Province of Quebec. During 1993 to 1995, we carried out a survey in 10 hospitals located in southern Quebec. During that time, umbilical cord blood samples were obtained from 1109 newborns, and we analyzed each for lead, mercury, 14 polychlorinated biphenyl congeners, and 11 chlorinated pesticides. We used the geometric mean and 95% confidence interval (CI) to describe the results. Mean concentrations of lead and mercury in cord blood were 0.076 micromol/l (95% CI = 0.074, 0.079) and 4.82 nmol/l (95% CI = 4.56, 5.08), respectively. The mean concentrations of total polychlorinated biphenyls (Aroclor 1260) and dichlorodiphenyl dichloroethylene were 0.514 microg/I (95% CI = .493, 0.536) and 0.412 microg/l (95% CI = 0.390, 0.435), respectively. We observed a statistically significant relationship between maternal age and cord blood concentrations of (a) lead, (b) mercury, (c) polychlorinated biphenyls, and (d) dichlorodiphenyl dichloroethylene. In addition, maternal smoking during pregnancy was associated with cord blood lead levels. The cord blood concentrations of lead, mercury, polychlorinated biphenyls, and dichlorodiphenyl dichloroethylene we measured in our study were the lowest levels recently reported in industrialized countries. The results of this study underline the role of public health authorities in the evaluation of biological levels of environmental contaminants among children for the assessment of risk of adverse health effects.

Objective: To compare mean concentrations of organochlorine in women with a new diagnosis of endometriosis and in controls., Design: Case-control study., Setting: Women attending an institutional clinic of reproductive endocrinology., Patient(s): Cases and controls were selected among women who underwent laparoscopy for chronic pelvic pain, infertility, or tubal fulguration between January 1994 and December 1994. Eighty-six women with endometriosis and 70 controls, matched for the indication for laparoscopy, were recruited., Main Outcome Measure(s): Mean organochlorine plasma concentrations of 14 polychlorinated biphenyl congeners and 11 chlorinated pesticides were compared between the cases and controls. Analysis of covariance was used to adjust means for confounding variables, and odds ratios were estimated by logistic regression., Result(s): Crude geometric mean concentrations did not differ significantly between cases and controls for any of the organochlorine compounds. Similarly, crude or adjusted means of the sum of polychlorinated biphenyl congeners, the sum of chlordanes, or the sum of dichlorodiphenyltrichloroethanes did not differ between the groups. There was no significant linear trend in the adjusted odds ratios for endometriosis as organochlorine concentrations increased., Conclusion(s): These results suggest that exposure to polychlorinated biphenyls and chlorinated pesticides during adulthood is not associated with endometriosis in the general population.

Inuit people (Eskimos) are likely exposed to persistent organochlorine compounds because their traditional diet includes fatty tissues of the arctic marine biota. Here we present the results of organochlorine compound analysis in milk fat samples from arctic Québec Inuit women and in fat tissues from various animal species inhabiting that region. The total concentration of polychlorinated biphenyl congeners in Inuit milk fat was similar to that of the beluga, while the profile of the 10 congeners resembled that of the polar bear. Mean concentrations of various organochlorines in milk-fat samples from Inuit women were between 2 and 10 times greater than those found in samples previously collected from southern Québec women. The Inuit mothers exhibit the greatest body burden known to occur from exposure to organochlorine residues present in the environment by virtue of their location at the highest trophic level of the arctic food web.