Abstract  OBJECTIVE: We investigated the association between body mass index (BMI) standard deviation score (SDS) and prenatal exposure to hexachlorobenzene, dichlorodiphenyldichloroethylene (DDE), dioxin-like compounds, and polychlorinated biphenyls (PCBs). METHODS: In this prospective birth cohort study, we assessed a random sample of mother-infant pairs (n = 138) living in Flanders, Belgium, with follow-up until the children were 3 years of age. We measured body mass index as standard deviation scores (BMI SDS) of children 1-3 years of age as well as pollutants measured in cord blood. RESULTS: DDE correlated with BMI SDS, with effect modification by maternal smoking and the child's age. At 1 year, children of smoking mothers had higher BMI SDS than did children of nonsmoking mothers. At 3 years, this difference was reduced because of the faster rate of decline in BMI SDS in the former group. This relationship held except for children with high levels of DDE. DDE had a small effect on BMI SDS at 3 years of age in children of nonsmoking mothers (difference in BMI SDS for DDE concentrations between the 90th and 10th percentiles = 0.13). On the other hand, smoking enhanced the relation between DDE and BMI SDS at 3 years (difference in BMI SDS for DDE concentrations between the 90th and 10th percentiles = 0.76). Increasing concentrations of PCBs were associated with higher BMI SDS values at all ages (parameter estimate = 0.003 +/- 0.001; p = 0.03). CONCLUSION: In this study we demonstrated that intrauterine exposure to DDE and PCBs is associated with BMI during early childhood. Future studies are warranted to confirm our findings and to assess possible mechanisms by which these pollutants could alter energy metabolism.

Abstract  Polychlorinated biphenyls (PCBs), chlorinated pesticides, and mercury are global environmental contaminants that can disrupt the endocrine system in animals and humans. However, there is little evidence that they can interfere with endocrine status in pregnant women and neonates at low levels of exposure. The aim of this study was to examine thyroid hormone levels during pregnancy and in cord blood in relation to blood concentrations of organochlorine compounds (OCs) and Hg in healthy women recruited during pregnancy. We found a significant negative correlation between maternal total triiodothyronine levels and three non-coplanar congeners (PCB-138, PCB-153, and PCB-180), three pesticides (p,p′-DDE, cis-nanochlor, and hexachlorobenzene), and inorganic Hg independently, without any other changes in thyroid status. No significant relationships were observed between OCs and cord serum thyroid hormones. Cord serum free thyroxin was negatively correlated with inorganic Hg. These results suggest that at even low levels of exposure, persistent environmental contaminants can interfere with thyroid status during pregnancy.

Abstract  BACKGROUND: Several epidemiologic studies have demonstrated relationships between prenatal exposure to polychlorinated biphenyls (PCBs) and modest cognitive impairments in infancy and early childhood. However, few studies have followed cohorts of exposed children long enough to examine the possible impact of prenatal PCB exposure on psychometric intelligence in later childhood. Of the few studies that have done so, one in the Great Lakes region of the United States reported impaired IQ in children prenatally exposed to PCBs, whereas another found no association. OBJECTIVES: This study was designed to determine whether environmental exposure to PCBs predicts lower IQ in school-age children in the Great Lakes region of the northeastern United States. METHODS: We measured prenatal exposure to PCBs and IQ at 9 years of age in 156 subjects from Oswego, New York. We also measured > 50 potential predictors of intelligence in children, including repeated measures of the home environment [Home Observation for Measurement of the Environment (HOME)], socioeconomic status (SES), parental IQ, alcohol/cigarette use, neonatal risk factors, and nutrition. RESULTS: For each 1-ng/g (wet weight) increase in PCBs in placental tissue, Full Scale IQ dropped by three points (p = 0.02), and Verbal IQ dropped by four points (p = 0.003). The median PCB level was 1.50 ng/g, with a lower quartile of 1.00 ng/g and an upper quartile of 2.06 ng/g. Moreover, this association was significant after controlling for many potential confounders, including prenatal exposure to methylmercury, dichlorodiphenyldichloroethylene, hexachlorobenzene, and lead. CONCLUSIONS: These results, in combination with similar results obtained from a similar study in the Great Lakes conducted 10 years earlier, indicate that prenatal PCB exposure in the Great Lakes region is associated with lower IQ in children.

Abstract  BACKGROUND: Several prospective studies have revealed that prenatal exposure to polychlorinated biphenyls (PCBs) and other organochlorine compounds (OCs) affect neurodevelopment during infancy. One of the mechanisms by which PCBs might interfere with neurodevelopment is a deficit in thyroid hormone (TH) concentrations. OBJECTIVES: We investigated the potential impact of transplacental exposure to PCBs and hexachlorobenzene (HCB) on TH concentrations in neonates from two remote coastal populations exposed to OCs through the consumption of seafood products. METHODS: Blood samples were collected at birth from the umbilical cord of neonates from Nunavik (n=410) and the Lower North Shore of the St. Lawrence River (n=260) (Québec, Canada) for thyroid parameters [thyroid-stimulating hormone (TSH), free T4 (fT4), total T3 (tT3), and thyroxine-binding globuline (TBG)] and contaminants analyses. RESULTS: In multivariate models, umbilical cord plasma concentrations of PCB 153, the predominant PCB congener, were not associated with TH and TSH levels in both populations. Prenatal exposure to HCB was positively associated with fT4 levels at birth in both populations (Nunavik, beta=0.12, p=0.04; St. Lawrence, beta=0.19, p<0.01), whereas TBG concentrations were negatively associated with PCB 153 concentrations (beta=-0.13, p=0.05) in the St. Lawrence cohort. CONCLUSION: OCs levels were not associated to a reduction in THs in neonates from our two populations. Essential nutrients derived from seafood such as iodine may have prevented the negative effects of OCs on the thyroid economy during fetal development.

Abstract  INTRODUCTION: Several epidemiological studies have reported that some organochlorine compounds (OCs), such as polychlorobiphenyls (PCBs) and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4'-DDE), may alter thyroid function. OBJECTIVE: The aim of the present study was to investigate the association of maternal serum OC concentrations of 4,4'-DDE and the sum of seven PCB congeners (PCB 28, 52, 101, 118, 138, 153, and 180) with thyroid hormone (TH) status. METHODS: We measured OC concentrations in 157 maternal serum samples at 12 weeks of pregnancy in a cohort from Valencia (Spain). Thyroid-stimulating hormone (TSH), total triiodothyronine (TT3), and free thyroxine (FT4) were measured as biomarkers of thyroid function in the same samples. Linear and logistic regression analyses were performed between OCs and TH levels, and variables were log transformed. RESULTS: Mothers with higher levels of 4,4'-DDE had higher odds of having TSH levels >2.5 mIU/L (OR=2.53; 95% CI=1.36; 4.73; p=0.004), and we found a significant negative association between serum 4,4'-DDE concentrations and FT4 levels (beta=-0.03; 95% CI=-0.05; 0.00; p=0.050) after adjustment for covariates and total lipids. No association was found between sum of PCBs and TH levels. CONCLUSION: Serum concentrations of 4,4'-DDE were associated with increased TSH and reduced FT4 but not TT3 levels. Our results suggest that some environmental chemicals may interfere with the thyroid system of pregnant women. The major role that maternal THs may play in fetal neurodevelopment makes these findings especially relevant.

Abstract  Wildlife studies suggest that consumption of contaminated fish from the Great Lakes may expose humans to polychlorinated biphenyls and persistent chlorinated pesticides. To assess whether time to pregnancy or fecundability is affected, we conducted a telephone survey in 1993 with female members of the New York State Angler Cohort Study who were considering pregnancy between 1991 and 1994 (N = 2,445). Among the 1,234 (50%) women who became pregnant, 895 (73%) had a known time to pregnancy. Upon enrollment into the cohort in 1991, both partners reported duration and frequency of Lake Ontario sport fish consumption. We estimated lifetime exposure to polychlorinated biphenyls from recent consumption and used a discrete-time analog of Cox proportional hazards analysis to estimate conditional fecundability ratios and 95% confidence intervals (CIs) for fish consumption among couples with complete exposure data who discontinued birth control to become pregnant (N = 575). Maternal consumption of fish for 3-6 years was associated with reduced fecundability (fecundability ratio = 0.75; 95% CI = 0.59-0.91), as was more than a monthly fish meal in 1991 (fecundability ratio = 0.73; 95% CI = 0.54-0.98). Our findings suggest that maternal but not paternal consumption of contaminated fish may reduce fecundability among couples attempting pregnancy.

Abstract  The aim of this study was to examine the effects of prenatal and postnatal chronic exposure to mercury (Hg), polychlorinated biphenyls (PCBs) and lead (Pb) on the neuromotor development of preschool children. The study population consisted of 110 preschool Inuit children from Nunavik (Canada). Blood Hg, PCBs and Pb concentrations were measured at birth (cord blood) and at the time of testing. Gross motor functions were evaluated and a neurological examination was performed. Fine neuromotor performance was assessed using quantitative measures of postural hand tremor, reaction time, sway oscillations, as well as alternating and pointing movements. Potential covariates were documented including demographic and familial characteristics, other prenatal neurotoxicants (alcohol, tobacco) and nutrients (selenium (Se), Omega-3 polyunsaturated fatty acids (n-3 PUFA)). Hierarchical multivariate regression analyses were performed, controlling for significant covariates. Gross motor development was not linked to prenatal exposures. However, significant associations were observed between blood Pb concentration at testing time and changes in reaction time, sway oscillations, alternating arm movements and action tremor. For some of these outcomes, neuromotor effects of Pb exposure are observed at blood concentrations below 10 μg/dl. Negative effects of PCBs on neuromotor development were not clearly observed, neither were the potential beneficial effects of n-3 PUFA and selenium. Tremor amplitude was related to blood Hg concentrations at testing time, which corroborate an effect already reported among adults.

Abstract  Background: Production of polychlorinated biphenyls (PCBs) ended in the United States in the 1970s, but PCBs persist in the environment and are detectable in the blood of approximately 80% of Americans over age 50. PCBs decrease dopamine levels in rats and monkeys. Loss of dopamine is the hallmark of Parkinson disease, a neurodegenerative disease. There are no epidemiologic studies of PCBs and neurodegenerative disease. Methods: We conducted a retrospective mortality study of 17,321 PCB-exposed workers to determine whether mortality from Parkinson disease, dementia, and amyotrophic lateral sclerosis was elevated compared with the U.S. population. All workers had a least 90 days employment in 1 of 3 electrical capacitor plants using PCBs from the 1940s to the 1970s. PCB serum levels from a sample of these workers in the 1970s were approximately 10 times the level of community controls. Results: We found no overall excess of Parkinson disease, amyotrophic lateral sclerosis, or dementia in the PCB-exposed cohort (standardized mortality ratios [SMRs]-1.40, 1.11, and 1.26, respectively, and number of deaths-14, 10, and 28 respectively). However, sex-specific analyses revealed that women had an excess of amyotrophic lateral sclerosis (SMR-2.26; 95% confidence interval [CI] = 1.08-4.15; 10 deaths). Furthermore, among highly exposed women (defined by a job-exposure matrix), we found an excess of Parkinson disease (SMR-2.95; 95% CI = 1.08-6.42; 6 deaths) and dementia (SMR-2.04; 95% CI = 1.12-3.43; 14 deaths). Conclusions: Our data are limited due to small numbers and reliance on mortality rather than incidence data, but are suggestive of an effect of PCBs on neurodegenerative disease for women. The literature does not offer an explanation for why women would be more affected than men by PCB exposure for these outcomes.

Abstract  Objective: To determine whether exposure to polychlorinated biphenyls (PCBs) or dichlorodiphenyl dichloroethene (DDE), either transplacentally or through breast feeding, affected scores on the Bayley Scales of Infant Development at 6 or 12 months of age. Design: Cohort followed from birth to 1 year of age. Setting: General community. Participants: Volunteer sample of 858 infants, of whom 802 had Bayley scores available at either 6 months or 12 months or both. Interventions: None. Measurements and main results: Bayley scales and chemical measurements were done independently. Higher transplacental exposure to PCBs was associated with lower psychomotor scores at both 6 and 12 months of age; the difference between the mean scores in the lowest and highest PCB groups was 7 points at 6 months and 8 points at 12 months. Higher transplacental exposure to DDE was associated with higher mental scores at 6 months of age (the difference between the mean scores in the lowest and highest DDE groups was 6 points), but no relationship was seen at 12 months. Exposure to either chemical through breast feeding was apparently unrelated to Bayley scores. Conclusions: Transplacental exposure to PCBs was associated with lower psychomotor scores. No deleterious effects were associated with breast feeding.

Abstract  Objective: Determining whether early developmental effects of perinatal exposure to polychlorinated biphenyls (PCBs) or dichlorodiphenyl dichloroethene (DDE) persist. Design: Cohort followed from birth; ages now 5 1/2 to 10 1/2 years. Setting: General community. Participants: Volunteer sample of 859 children, of whom 712 had been examinedwith the McCarthy Scales of Children's Abilities at 3, 4, or 5 years; 506 sent report cards. Interventions: None. Measurements and results: Neither transplacental nor breast-feeding exposure to PCBs or DDE affected McCarthy scores at 3, 4, or 5 years. There was no statistically significant relationship between poorer grades and PCB or DDE exposure by either route. Conclusions: The deficits seen in these children on the Bayley Scales of infantDevelopment through 2 years of age are no longer apparent.

Abstract  OBJECTIVE: This work was aimed to evaluate the fundamental relations between the blood levels of testosterone (TEST) and persistent organochlorinated pollutants (POPs) related to body mass index (BMI) and blood lipids in a cohort of heavily exposed males from Eastern Slovakia.

METHODS: In 429 middle aged (41-55 years) males heavily exposed to POPs the levels of 15 polychlorinated biphenyl congeners (Σ15PCBs), hexachlorobenzene (HCB), and dichlorodiethyl-dichloroethylene (p,p'-DDE) were measured by gas chromatography/mass spectrometry and the total testosterone (TEST) by electrochemiluminiscent immunoassay.

RESULTS: After classifying the values of BMI, TEST, HCB, p,p'-DDE, and Σ15PCBs in quintiles and evaluating mutual interrelations of individual quintile counts in pairs of variables with chi-square, statistically significant interrelation was found for BMI/TEST (<0.0001) and HCB/TEST (p<0.001), but not for p,p'-DDE/TEST (p<0.6036) and Σ15PCBs/TEST (p<0.3246). Moreover, highly significant negative correlation was found between HCB and TEST by means of both Pearson (p<0.01) and Spearman rank correlations (p<0.0001). However, similar correlations performed between p,p'-DDE and Σ15PCBs did not reveal statistical significance. Finally, highly significant positive correlations were found between HCB and BMI, age, total lipids, and triglycerides. However, these correlations were less significant for p,p'-DDE and not significant or even negligibly negative for Σ15PCBs. In contrast, correlations of TEST with BMI and lipid fractions were significantly negative.

CONCLUSION: It appears that HCB might play a role in a decrease of TEST in males with relatively narrow age range of males highly exposed to POPs. Highly significant positive correlation of HCB with BMI and blood lipids points out the role of BMI as an imaginary compartment closely related to the total body fat mass and representing a depot of POPs which is closely related to the level of POPs and lipids in blood. However, the differences in the affinity of individual POPs to BMI and blood lipids as well as the mechanism of their different relation to blood TEST levels remain to be still explained.

Abstract  BACKGROUND: Dichlorodiphenyldichloroethylene (DDE) and other organochlorines suppress immunity biomarkers in animals and humans. Our aim was to study the association between prenatal levels of DDE and lower respiratory tract infection in infants independently from polychlorinated biphenyls (PCBs) and other organochlorines. METHODS: Maternal levels of p'p'-DDE, dichlorodiphenyltrichloroethane (p'p-DDT), PCB congeners 28, 118, 138, 153, and 180, hexachlorobenzene, and beta-hexachlorocyclohexane were measured in first trimester serum of 584 pregnant women from a general population-based cohort in Sabadell (Catalonia, Spain). Mothers reported lower respiratory tract infection in interviewer-led questionnaires administered at infant age 6 and 14 months. RESULTS: Thirteen percent of babies had recurrent lower respiratory tract infection during the first 14 months of life. Among the organochlorines, DDE showed the highest levels (median = 112 ng/g lipid); dichlorodiphenyltrichloroethane was not detectable. The median total PCB level was 85 ng/g. DDE was the only organochlorine that showed an association with recurrent lower respiratory tract infection (at levels >83 ng/g, the first tertile, relative risk = 2.40 [95% confidence interval = 1.19-4.83]), lower respiratory tract infection at 6 months (1.68 [1.06-2.66]), and lower respiratory tract infection at 14 months (1.52 [1.05-2.21]). Adjusting for PCBs, hexachlorobenzene or beta-hexachlorocyclohexane did not confound the association. CONCLUSIONS: Immunologic suppression by DDE as observed in experimental studies could explain the relation between DDE and lower respiratory tract infection, independently of PCBs. Exposure to DDE during prenatal life could be critical for the development of the immune and respiratory systems.

Abstract  BACKGROUND: The incidence of non-Hodgkin lymphoma (NHL) has risen over the past several decades. Reasons for this increase are largely unexplained.

METHODS: In this population-based case-control study, we examined NHL risk and exposure to organochlorine compounds using concentrations in carpet dust as an exposure indicator. We identified NHL cases, uninfected with HIV, diagnosed between 1998 and 2000 among women and men ages 20-74 years in Iowa, Los Angeles County, and the Detroit and Seattle metropolitan areas. Controls were selected using random-digit-dialing or Medicare files. Organochlorine concentrations were measured in vacuum bag dust from 603 white cases and 443 white controls who had owned most of their carpets for at least 5 years.

RESULTS: NHL risk was elevated if any of the polychlorinated biphenyl (PCB) congeners (PCBs 105, 138, 153, 170, or 180) was detected (odds ratio = 1.5; 95% confidence interval = 1.2-2.0). Risk was elevated in the top tertile of PCB 180 (1.7; 1.1-2.6) and in the top 2 tertiles of total PCBs (middle tertile, 1.6 [1.1-2.4]; top tertile 1.5 [1.0-2.2]). There was a positive trend in risk with increasing PCB 180 levels (P trend = 0.03). NHL risk was elevated if dichlorodiphenyldichloroethylene (DDE) was detected (1.3; 1.0-1.7), but only among men. A positive, but not monotonic, dose-response relationship was observed for DDE (P trend = 0.02).

CONCLUSIONS: Our findings suggest an increased risk of NHL associated with exposure to PCBs, with evidence of greater effects for PCB 180. There is also some evidence of an association with DDE.

Abstract  BACKGROUND: Both genetic and environmental factors contribute to triglyceride, low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) levels. Although genome-wide association studies are currently testing the genetic factors systematically, testing and reporting one or a few factors at a time can lead to fragmented literature for environmental chemical factors. We screened for correlation between environmental factors and lipid levels, utilizing four independent surveys with information on 188 environmental factors from the Centers of Disease Control, National Health and Nutrition Examination Survey, collected between 1999 and 2006. METHODS: We used linear regression to correlate each environmental chemical factor to triglycerides, LDL-C and HDL-C adjusting for age, age(2), sex, ethnicity, socio-economic status and body mass index. Final estimates were adjusted for waist circumference, diabetes status, blood pressure and survey. Multiple comparisons were controlled for by estimating the false discovery rate and significant findings were tentatively validated in an independent survey. RESULTS: We identified and validated 29, 9 and 17 environmental factors correlated with triglycerides, LDL-C and HDL-C levels, respectively. Findings include hydrocarbons and nicotine associated with lower HDL-C and vitamin E (γ-tocopherol) associated with unfavourable lipid levels. Higher triglycerides and lower HDL-C were correlated with higher levels of fat-soluble contaminants (e.g. polychlorinated biphenyls and dibenzofurans). Nutrients and vitamin markers (e.g. vitamins B, D and carotenes), were associated with favourable triglyceride and HDL-C levels. CONCLUSIONS: Our systematic association study has enabled us to postulate about broad environmental correlation to lipid levels. Although subject to confounding and reverse causality bias, these findings merit evaluation in additional cohorts.

Abstract  To determine whether prenatal exposure to polychlorinated biphenyls (PCBs) with possible hormone-disrupting effects is capable of affecting sexual differentiation in boys at the age of puberty.

Following analysis for PCB in their umbilical cords, 196 boys from a Faroese birth cohort were examined for the development of puberty at 14 years of age.

Physical examination included determination of Tanner stages and testicular size. A morning urine sample was centrifuged and examined for the presence of sperm. Serum was analyzed for sex hormones.

twenty boys (10.2%) had abnormalities in testicular development, mainly cryptorchidism. only three of them had a positive spermaturia test, but the level of exposure to pcbs in this group had not been increased. occurrence of spermaturia in 58 of the remaining 176 boys was also not associated with pcb exposure but showed highly significant associations with tanner stages and testicular size. serum concentrations of testosterone, fsh and lh were higher in boys with spermaturia, while sex hormone-binding globulin was lower and no difference occurred in inhibin b. serum hormone parameters showed only weak associations with the level of prenatal pcb exposure.

These findings support the validity of spermaturia as a useful indicator of puberty, although a substantial rate of false negatives must be taken into account. Despite the wide range of exposure to PCB, the findings did not reveal any definite associations with the development of puberty. However, because of the limited size of the cohort, small effects cannot be excluded.

Abstract  Prenatal and postnatal polychlorinated biphenyl (PCBs) exposure has been associated with decrements in fetal and infant growth and development, although exposures during the preconception window have not been examined despite recent evidence suggesting that this window may correspond with the highest serum concentrations.

We assessed maternal serum PCB concentrations at two sensitive developmental windows in relation to birth weight.

Serum samples were collected from 99 women as they began trying to become pregnant (preconception) and after a positive pregnancy test (prenatal); 52 (53%) women gave birth and represent the study cohort. Using daily diaries, women recorded sexual intercourse, menstruation, and home pregnancy test results until pregnant or up to 12 menstrual cycles with intercourse during the estimated fertile window. With gas chromatography with electron capture, 76 PCB congeners were quantified (nanograms per gram serum) and subsequently categorized by purported biologic activity. Serum PCBs were log-transformed and entered both as continuous and categorized exposures along with birth weight (grams) and covariates [smoking (yes/no), height (inches), and infant sex (male/female)] into linear regression.

A substantial reduction in birth weight (grams) was observed for women in the highest versus the lowest tertile of preconception antiestrogenic PCB concentration (beta; = 429.3 g, p = 0.038) even after adjusting for covariates (beta; = 470.8, p = 0.04).

These data reflect the potential developmental toxicity of antiestrogenic PCBs, particularly during the sensitive preconception critical window among women with environmentally relevant chemical exposures, and underscore the importance of PCB congener-specific investigation.

Abstract  Background: Human exposure to polychlorinated biphenyls (PCBs) remains widespread. PCBs have been associated with adverse reproductive health outcomes including reduced fecundability and increased risk of pregnancy loss, although the human data remain largely inconclusive.Objective: Our goal was to explore the relationship between serum PCB concentrations and early pregnancy loss among a large cohort of women undergoing in vitro fertilization (IVF) between 1994 and 2003.Methods: Concentrations of 57 PCB congeners were measured in serum samples collected during 827 IVF/intracytoplasmic sperm injection cycles from 765 women. Joint statistical models that accommodate multiple outcomes and multiple cycles per woman were used to assess the relationship between serum PCB quartiles and implantation failure, chemical pregnancies (human chorionic gonadotropin level > 5.0 mIU/mL) that did not result in clinical pregnancy, or spontaneous abortion, while also adjusting for confounders.Results: PCB-153 was the congener present in the highest concentration (median, 46.2 ng/g lipid). Increasing quartiles of PCB-153 and the sum of all measured PCB congeners (ΣPCBs) were associated with significantly elevated dose-dependent odds of failed implantation. Adjusted odds ratios (95% confidence interval) for highest versus lowest quartile were 2.0 (1.2-3.4) for PCB-153 and 1.7 (1.0-2.9) for ΣPCBs. There were suggestive trends for increased odds of implantation failure for PCB-118 and cytochrome P450-inducing congeners (p-values for trend = 0.06). No statistically significant associations between PCBs and chemical pregnancy or spontaneous abortion were found.Conclusions: Serum PCB concentrations at levels similar to the U.S. general population were associated with failed implantation among women undergoing IVF. These findings may help explain previous reports of reduced fecundability among women exposed to PCBs.

Abstract  Polychlorinated biphenyls (PCB)/polychlorinated dibenzofurans (PCDF) are known to affect central nervous functioning. In recent studies, elderly patients who have been exposed to these have been noted to have psychological deficits. There is little known about which test is sensitive to neurotoxins in cognitive evaluation. The objective of the present study was to compare the significance between selective psychological tests in cognitive assessment in PCB-laden elderly.

A retrospective PCB/PCDF exposed cohort was observed. Exposed elderly aged ≥ 60 years and registered in Central Health Administration were enrolled, and similar age- and sex-matched subjects served as non-exposed controls. The Mini-Mental State Examination (MMSE) and Attention and Digit Span (ADS) were tested in both groups. Student's t-test, χ(2) -test and linear regression models were used for statistical analysis.

 A total of 165 exposed patients and 151 controls were analyzed. The exposed group included 49% men, a mean age of 69.3 ± 6.4 years and an education level of 4.0 ± 3.9 years. The controls included 52% men, a mean age of 69.9 ± 5.5 years and an education level of 4.5 ± 3.2 years. There was no statistical difference in MMSE before and after adjusting for the confounding variables of age, sex and education (P= 0.16 vs P= 0.12). However, ADS-forward and ADS-total scores showed a significant decline in the exposed subjects (P= 0.0001 vs P= 0.001). Using a linear regression among stratified PCB and cognitive functioning (≤30 ppb; 31-89; ≥90), a dose effect was found at the medium (31-89 ppb) and high exposure (≧90 ppb) levels.

Our observations showed attention and short-term memory were impaired in PCB-laden elderly patients. Higher exposure level showed lower cognitive functioning in ADS. The MMSE was insensitive to neurotoxins. The present study shows that the selective test has a decisive role in toxic-related cognitive assessments.

Abstract  Though commercial production of polychlorinated biphenyls was banned in the United States in 1977, exposure continues due to their environmental persistence. Several studies have examined the association between environmental polychlorinated biphenyl exposure and modulations of the secondary sex ratio, with conflicting results.

Our objective was to evaluate the association between maternal preconceptional occupational polychlorinated biphenyl exposure and the secondary sex ratio.

We examined primipara singleton births of 2595 women, who worked in three capacitor plants at least one year during the period polychlorinated biphenyls were used. Cumulative estimated maternal occupational polychlorinated biphenyl exposure at the time of the infant's conception was calculated from plant-specific job-exposure matrices. A logistic regression analysis was used to evaluate the association between maternal polychlorinated biphenyl exposure and male sex at birth (yes/no).

Maternal body mass index at age 20, smoking status, and race did not vary between those occupationally exposed and those unexposed before the child's conception. Polychlorinated biphenyl-exposed mothers were, however, more likely to have used oral contraceptives and to have been older at the birth of their first child than non-occupationally exposed women. Among 1506 infants liveborn to polychlorinated biphenyl-exposed primiparous women, 49.8% were male; compared to 49.9% among those not exposed (n = 1089). Multivariate analyses controlling for mother's age and year of birth found no significant association between the odds of a male birth and mother's cumulative estimated polychlorinated biphenyl exposure to time of conception.

Based on these data, we find no evidence of altered sex ratio among children born to primiparous polychlorinated biphenyl-exposed female workers.

Abstract  There is emerging evidence that background exposure to persistent organic pollutants (POPs) are important in the development of conditions predisposing to diabetes as well as of type 2 diabetes itself. We recently reported that low dose POPs predicted incident type 2 diabetes in a nested case-control study. The current study examined if low dose POPs predicted future adiposity, dyslipidemia, and insulin resistance among controls without diabetes in that study.

The 90 controls were diabetes-free during 20 years follow-up. They were a stratified random sample, enriched with overweight and obese persons. POPs measured in 1987-88 (year 2) sera included 8 organochlorine (OC) pesticides, 22 polychlorinated biphenyls (PCBs), and 1 polybrominated biphenyl (PBB). Body mass index (BMI), triglycerides, HDL-cholesterol, LDL-cholesterol, and homeostasis model assessment value for insulin resistance (HOMA-IR) were study outcomes at 2005-06 (year 20). The evolution of study outcomes during 18 years by categories of serum concentrations of POPs at year 2 was evaluated by adjusting for the baseline values of outcomes plus potential confounders. Parallel to prediction of type 2 diabetes, many statistically significant associations of POPs with dysmetabolic conditions appeared at low dose, forming inverted U-shaped dose-response relations. Among OC pesticides, p,p'-DDE most consistently predicted higher BMI, triglycerides, and HOMA-IR and lower HDL-cholesterol at year 20 after adjusting for baseline values. Oxychlordane, trans-nonachlor, and hexachlorobenzene also significantly predicted higher triglycerides. Persistent PCBs with ≥7 chlorides predicted higher BMI, triglycerides, and HOMA-IR and lower HDL-cholesterol at year 20 with similar dose-response curves.

Simultaneous exposure to various POPs in the general population may contribute to development of obesity, dyslipidemia, and insulin resistance, common precursors of type 2 diabetes and cardiovascular diseases. Although obesity is a primary cause of these metabolic abnormalities, POPs exposure may contribute to excess adiposity and other features of dysmetabolism.

Abstract  Most epidemiological studies of the association between breast cancer risk and exposure to organochlorine pesticides or polychlorinated biphenyls (PCBs), which are suspected endocrine disrupters and potential risk factors for human breast cancer, have been conducted in western countries, and the majority of results have been null and the rest inconsistent. Here, we examined these associations in Japanese women in the largest study in Asian women to date.

The study was a matched case-control study of breast cancer with 403 eligible matched pairs from May 2001 to September 2005 at four hospitals in Nagano Prefecture, Japan.

Serum samples were measured for PCBs and nine pesticide-related organochlorines, including dichlorodiphenyltrichloroethane (DDT). Odds ratios of breast cancer or its hormone-receptor-defined subtypes according to serum organochlorines were calculated.

No increase in the risk of breast cancer was seen among women with higher serum concentrations of any organochlorine: o,p'-DDT, p,p'-DDT, p,p'-dichlorodiphenyldichloroethylene, hexachlorobenzene, beta-hexachlorocyclohexane, trans-nonachlor, cis-nonachlor, oxychlordane, mirex, or PCBs. Rather, higher serum levels of cis-nonachlor, mirex, or total PCBs were associated with a decreased risk of breast cancer

Overall, these results suggest that breast cancer risk in Japan, a low-incidence country, is similar to that in western countries in terms of organochlorine exposure.

Abstract  The present study reports the association between prenatal exposure to polychlorinated biphenyls (PCBs), the corpus callosum, and response inhibition in children who are 4.5 years old. Children (n = 189) enrolled in the Oswego study were tested using a continuous performance test. We measured (square millimeters) the splenium of the corpus callosum, a pathway implicated in the regulation of response inhibition, using magnetic resonance imaging. Results indicated a dose-dependent association between cord blood PCBs and errors of commission. Splenium size but not other brain areas predicted errors of commission (r(2) = 0.20), with smaller size associated with more errors of commission. There was an interaction between splenium size and PCB exposure. The smaller the splenium, the larger the association between PCBs and errors of commission. If the association between PCBs and response inhibition is indeed causal, then children with suboptimal development of the splenium are particularly vulnerable to these effects. These data await replication.

Abstract  BACKGROUND: Developmental exposure to polychlorinated biphenyls (PCBs) has been implicated as a possible cause of deficient immune function in children. This study was designed to assess whether prenatal and postnatal exposure to PCBs impacts on antibody response to childhood immunizations.

METHODS AND FINDINGS: Two birth cohorts were formed in the Faroe Islands, where exposures vary widely, because traditional diets may include whale blubber contaminated with PCBs. Prenatal exposure was determined from maternal concentrations of PCBs in pregnancy serum and milk. Following routine childhood vaccinations against tetanus and diphtheria, 119 children were examined at 18 mo and 129 children at 7 y of age, and their serum samples were analyzed for tetanus and diphtheria toxoid antibodies and for PCBs. The antibody response to diphtheria toxoid decreased at age 18 mo by 24.4% (95% confidence interval [CI], 1.63-41.9; p = 0.04) for each doubling of the cumulative PCB exposure at the time of examination. The diphtheria response was lower at age 7 y and was not associated with the exposure. However, the tetanus toxoid antibody response was affected mainly at age 7 y, decreasing by 16.5% (95% CI, 1.51-29.3; p = 0.03) for each doubling of the prenatal exposure. Structural equation analysis showed that the early postnatal exposure was the most important predictor of a decreased vaccination response.

CONCLUSIONS: Increased perinatal exposure to PCBs may adversely impact on immune responses to childhood vaccinations. The clinical implications of insufficient antibody production emphasize the need for prevention of immunotoxicant exposures.

Abstract  Environmental chemicals are thought to adversely affect human reproductive function, however there are no studies that have explored the association between failed fertilization and exposure of both partners to environmental contaminants. Therefore, we collected blood and follicular fluid from the female partner and seminal plasma from the male partner of 21 couples attending an in vitro fertilization (IVF) program, in order to determine the extent of the existence of environmental chemicals in these fluids. Any relationship to the outcome of IVF was also considered. Sera and fluids were analysed for a variety of contaminants, including polychlorinated biphenyls, pesticides, cotinine, and the steroids progesterone and estradiol. Of the couples examined, 18 had fertilizations, three of whom became pregnant. There were no fertilizations in three other couples. The contaminants most frequently found in follicular fluid, more than 50% of the samples tested, were p,p'-DDE, mirex, hexachloroethane, 1,2,4-trichlorobenzene, PCB 49, PCB 153, and PCB 180. Cadmium was detected in eight of 21 (38.1%) samples of follicular fluid whereas cotinine was detected in 18 (85.7%). Residue levels of p,p'-DDE, endosulfan I, PCB 99, PCB 138, PCB 153, PCB 180 were quantified in more than 50% of the sera samples examined. Seminal plasma was relatively free of pollutants with mirex being the most frequently detected contaminant found in seven of 21 (33.3%) samples. Mirex could not be detected in the seminal plasma of the husbands whose partner's oocytes failed to fertilize whereas significant levels of mirex were found in the seminal plasma of all couples who had a pregnancy. Cadmium was also found in the follicular fluid of these pregnant subjects. No relationship was found between follicular fluid cotinine in pregnant and non-pregnant subjects. Where identical contaminants were found in both sera and follicular fluids, the levels were about twofold higher in serum and were positively correlated in both fluids. Fertilization was negatively correlated with serum and follicular fluid p,p'-DDE whereas pregnancy was positively correlated with follicular fluid PCB 49. These data reveal that more than 50% of the population of women attending a fertility program have had exposure to environmental chemicals sufficient to produce detectable concentrations in their serum and ovarian follicular fluid. Of the chemical contaminants detected in the serum and follicular fluid of these women, p,p'-DDE was the most frequently detected, had the highest residue levels, and was associated with failed fertilization.

Abstract  Spirometric findings (forced vital capacity [FVC], forced expiratory volume at one second [FEV1], FEV1/FVC) in a population of capacitor workers with occupational exposure to polychlorinated biphenyls (PCBs) are described during active PCB use (1976) and following the PCB ban (1979 and 1983). The initial finding of restrictive impairment (16%) in 1976 was not supported by chest roentgenogram findings, nor confirmed in 1979 and 1983, and was interpreted as artifactual due to test operator inexperience and inadequate expiratory efforts. Obstructive impairment was consistently found in 15% of the total population in 1976 and 1979. A history of respiratory illness and/or symptomatology and reduced FEV1/FVC was correlated with PCB exposure and serum PCB levels (lower homologs) in females in 1976, but not in males. Smoking was correlated with reduced FEV1 values. No correlation of spirometric variables with past exposure or serum PCB levels was found for either sex in 1979.