Search

Background: Several our previous studies showed associations of increasing blood level of persistent organochlorinated pollutants (POPs) with individual thyroid and metabolic adverse health signs in subjects from heavily polluted area (POLL) compared to these from the area of background pollution (BCGR). In this study we present increasing number of subjects with multiple adverse signs positively associated with blood level of polychlorinated biphenyls (PCBs) which is used as a marker of other POPs cocktail. Methods: In a total of 2046 adults (834 males and 1212 females; age range 21-75) from POLL and BCGR the serum level of major POPs such as of 15 most abundant PCBs congeners, dichlorodiphenyl-dichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB) was estimated by high resolution gas chromatography. In addition, the data on thyroid volume by ultrasound and body mass index were obtained and serum level of thyroperoxidase and thyrotropin receptor antibodies as well as that of free thyroxine, total triiodothyronine, thyrotropin, thyroglobulin, fasting glucose and insulin, cholesterol and triglycerides was measured. Thus, a total of 13 adverse signs were defined and the interrelations between PCBs level and increasing number of subjects with increasing number of adverse signs were evaluated. Results: Because of high correlation between major POPs (PCB, DDE and HCB), for this purpose the level of PCBs was considered as a marker also for the presence of DDE and HCB. Thus, if all data obtained from 2046 subjects were stratified according to quintiles of PCBs level, highly significant increase was found (p < 0.02 to 0.0000 by chi-sqauare) for the frequency of 8 among 13 signs, while the increase of one additional sign was slightly above significance limit and that in 4 other was not significant. Also the number of subjects with multiple adverse signs was significantly higher in POLL than in BCGR. For instance, in BCGR area (1038 subjects; median PCB level of 744 ng/g and 5%-95% range of 423 - 1329 ng/g serum lipids) there were 84 (8.1%) cases with 6 or 7 adverse health signs, while in POLL area (1008 subjects; median PCB level of 1892 ng/g; 5%-95% range of 685 - 9016 ng/g) the prevalence of respective cases was twice as high (195 cases = 19.3%; p < 0.001 by chi-square). For the subjects with the same PCB levels, but with 8 or 9 adverse signs the respective values were 22/1038 (2.1%) vs. 54/1008 (5.3%; p < 0.001). Conclusion: Significantly higher accumulation of adverse signs in subjects with high POPs level was found in POLL thus supporting the conclusion that POPs appear to increase the prevalence of several subclinical and overt thyroid and metabolic disorders. [ABSTRACT FROM AUTHOR]

Abstract: Polychlorinated biphenyls (PCBs) were commercially produced between 1959 and 1984 in eastern Slovakia. Improper handling led to a highly contaminated local environment and high levels of PCBs in humans and wildlife in the Michalovce area. The aim of this study was to analyse serum for methylsulfonyl metabolites of PCB (MeSO2-PCBs) and DDE (3-MeSO2-DDE) in serum samples from pregnant women and in a selected number of paired cord blood samples to assess maternal sulfone levels and patterns, and transplacental transfer of these metabolites. The donating women were from two districts in eastern Slovakia. A liquid–liquid extraction method together with separation of substance groups and further clean-up on silica gel columns were applied prior to analysis by gas chromatography/mass spectrometry. 3-MeSO2-DDE was the major methyl sulfone in most of the samples followed by a yet not identified MeSO2-hexaCB, 4′-MeSO2-CB101, 4′-MeSO2-CB87 and 4-MeSO2-CB149. The women from the contaminated area had three times higher concentrations of the MeSO2-PCBs than women from the reference area. This is the first report on methyl sulfone metabolites of PCB and DDE in human cord serum. It is shown that these metabolites are transported through the placenta. The levels of MeSO2-PCBs in the maternal serum were about 1.5 times higher than in the corresponding cord serum on a lipid weight basis. For 3-MeSO2-DDE, the levels were about the same in maternal and cord serum. The difference in the maternal:cord ratio, comparing MeSO2-PCBs with 3-MeSO2-DDE might be due to differences in transport through the placenta caused by their different affinities for lipoproteins and plasma proteins. [Copyright &y& Elsevier]

As part of a large human biomonitoring study, we conducted occupational monitoring in a glass fibre factory in Slovakia. Shopfloor workers (n = 80), with a matched group of administrators in the same factory (n = 36), were monitored for exposure to glass fibres and to polycyclic aromatic hydrocarbons (PAHs). The impact of occupational exposure on chromosomal aberrations, DNA damage and DNA repair, immunomodulatory markers, and the role of nutritional and lifestyle factors, as well as the effect of polymorphisms in metabolic and DNA repair genes on genetic stability, were investigated. The (enzyme-modified) comet assay was employed to measure DNA strand breaks (SBs) and apurinic sites, oxidised and alkylated bases. Antioxidant status was estimated by resistance to H 2 O 2 -induced DNA damage. Base excision repair capacity was measured with an in vitro assay (based on the comet assay). Exposure of workers to fibres was low, but still was associated with higher levels of SBs, and SBs plus oxidised bases, and higher sensitivity to H 2 O 2. Multivariate analysis showed that exposure increased the risk of high levels of SBs by 20%. DNA damage was influenced by antioxidant enzymes catalase and glutathione S-transferase (measured in blood). DNA repair capacity was inversely correlated with DNA damage and positively with antioxidant status. An inverse correlation was found between DNA base oxidation and the percentage of eosinophils (involved in the inflammatory response) in peripheral blood of both exposed and reference groups. Genotypes of XRCC1 variants rs3213245 and rs25487 significantly decreased the risk of high levels of base oxidation, to 0.50 (p = 0.001) and 0.59 (p = 0.001), respectively. Increases in DNA damage owing to glass fibre exposure were significant but modest, and no increases were seen in chromosome aberrations or micronuclei. However, it is of concern that even low levels of exposure to these fibres can cause significant genetic damage. • Exposure of workers to glass fibres was associated with increased levels of DNA damage and higher sensitivity to H 2 O 2. • DNA damage was influenced by catalase activity and glutathione S-transferase levels measured in peripheral blood. • XRCC1 variants rs3213245 and rs25487 were associated with a decrease in the risk of high DNA oxidation damage. • Glass fibre exposure did not affect the levels of chromosome aberrations or micronuclei in exposed workers. [ABSTRACT FROM AUTHOR]

Background: Despite experimental evidence that lactational exposure to persistent organic pollutants (POPs) can impact health, results from epidemiologic studies are inconclusive. Inconsistency across studies may reflect the inability of current methods to estimate children's blood levels during specific periods of susceptibility. Objectives: We developed a toxicokinetic model to simulate blood POP levels in children from two longitudinal birth cohorts and aimed to validate it against blood levels measured at 6, 16, and 45 months of age. Methods: The model consisted of a maternal and a child lipid compartment connected through placental diffusion and breastfeeding. Simulations were carried out based on individual physiologic parameters; duration of breastfeeding; and levels of POPs measured in maternal blood at delivery, cord blood, or breast milk. Model validity was assessed through regression analyses of simulated against measured blood levels. Results: Simulated levels explained between 10% and 83% of measured blood levels depending on the cohort, the compound, the sample used to simulate children's blood levels, and child's age when blood levels were measured. Model accuracy was highest for estimated blood POP levels at 6 months based on maternal or cord blood levels. However, loss in model precision between the 6th and the 45th month was small for most compounds. Conclusions: Our validated toxicokinetic model can be used to estimate children's blood POP levels in early to mid-childhood. Estimates can be used in epidemiologic studies to evaluate the impact of exposure during hypothesized postnatal periods of susceptibility on health. [ABSTRACT FROM AUTHOR]

Background: Previously, we reported an association between higher maternal polychlorinated biphenyl (PCB) concentrations and smaller thymus volume in newborns in a birth cohort residing in eastern Slovakia. Objective: In the present report we address whether thymus volume at later ages is influenced by prenatal and early postnatal PCB exposure. Methods: At the time of delivery, 1,134 mother-infant pairs were enrolled. Maternal and 6- and 16-month infant blood samples were collected and analyzed for 15 PCB congeners. Thymus volume was measured in infants shortly after birth and at ages 6 and 16 months using ultrasonography. Results: Higher maternal PCB concentration was associated with reduced thymus volume at birth [a 0.21 SD reduction in thymus volume for an increase in total maternal PCB concentration from the 10th to the 90th percentile; 95% confidence interval (CI): -0.37, -0.05], whereas maternal PCB concentration was not predictive of 6- and 16-month thymus volume. Six-month infant PCB concentration was associated with a 0.40 SD decrease in 6-month thymus volume (95% CI: -0.76, -0.04). There was also some suggestion that thymus volume at 16 months was positively associated with concurrent infant PCB concentration. Conclusions: The potential adverse effects of in utero PCB exposure on thymic development may extend beyond the neonatal period. Results from this highly exposed cohort provide suggestive evidence that postnatal PCB concentrations may be influential, but a smaller set of 6-month PCB measurements limited statistical power at that time point. Implications regarding impaired immunologic maturation or long-term clinical implications remain to be determined. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyl (PCB) and polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) intake via nutrition (nursing, infant milk formula) by infants was evaluated. A cohort of mother-child pairs from an area contaminated with PCB by the Chemko chemical plant formerly producing PCB in eastern Slovakia was examined. Breast milk and blood serum were analysed for PCB and PCDD/F by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). The median daily intake of total toxic equivalent (TEQ) of dioxin-like PCB (dl-PCB) and PCDD/F from breast milk for fully breast-fed children was 72.8 pg·kg-1 body weight per day, assuming 7.6 kg as average body weight of the child. However, daily total intake of TEQ of non-breastfed children during the first 10 month of life was only 0.21 pg·kg-1 body weight per day on average. Dl-PCB-TEQ contributed to the total TEQ in breast milk with a higher proportion (68%) than PCDD/F-TEQ (32%) because of a much higher contamination of breast milk with PCB in general. The median of the sum of non-dioxin-like PCB (ndl-PCB) daily intake assuming 7.6 kg body weight was evaluated as 2 342 ng·kg-1 body weight per day and ranged from 8 ng·kg-1 to 13 124 ng·kg-1 body weight per day. [ABSTRACT FROM AUTHOR]

Animal data indicate that developmental tetrachlorodibenzo- p-dioxin exposure alters immune function; however, the potential immunotoxicity of dioxin-like and non-dioxin-like polychlorinated biphenyls (PCBs) in the developing infant is an understudied area. The aim of the current study is to examine the association between maternal and early postnatal PCB concentrations in relation to total infant serum immunoglobulin concentrations determined at 6-months-of-age. We selected 384 mother-infant pairs participating in a birth cohort study in Eastern Slovakia. PCB concentrations of several congeners were determined in maternal and cord serum samples and in infant serum samples collected at 6-months-of-age using gas chromatography with electron capture detection. Total immunoglobulin (Ig) G, A, and M concentrations were determined by nephelometry, and IgE concentrations were determined by enzyme-linked immunoassay. Linear regression models with adjustment for potential confounding factors were used to estimate the associations between maternal, cord, and 6-month infant PCB concentrations and total serum immunoglobulins. The median maternal serum concentration of PCB-153 was 140 ng/g lipid, ≈≈10-fold higher than concentrations in childbearing-age women in the United States during the same period. Maternal, cord, or 6-month infant PCB concentrations were not associated with total serum immunoglobulin levels at 6 months, regardless of the timing of PCB exposure, PCB congener, or specific immunoglobulin. In this population, which has high PCB concentrations relative to most populations in the world today, we did not observe any association between maternal and early postnatal PCB concentrations and total immunoglobulin measures of IgG, IgA, IgM, or IgE. [ABSTRACT FROM AUTHOR]

Abstract: Background: Extensive experimental data in animals indicate that exposure to polychlorinated biphenyls (PCBs) during pregnancy leads to changes in offspring immune function during the postnatal period. Whether developmental PCB exposure influences immunologic development in humans has received little study. Methods: The study population was 384 mother–infant pairs recruited from two districts of eastern Slovakia for whom prospectively collected maternal, cord, and 6-month infant blood specimens were available. Several PCB congeners were measured in maternal, cord, and 6-month infant sera by high-resolution gas chromatography with electron capture detection. Concentrations of IgG-specific anti-haemophilus influenzae type b, tetanus toxoid, and diphtheria toxoid were assayed in 6-month infant sera using ELISA methods. Multiple linear regression was used to estimate the relation between maternal, cord, and 6-month infant PCB concentrations and the antibody concentrations evaluated at 6-months of age. Results: Overall, there was little evidence of an association between infant antibody concentrations and PCB measures during the pre- and early postnatal period. In addition, our results did not show specificity in terms of associations limited to a particular developmental period (e.g. pre- vs. postnatal), a particular antibody, or a particular PCB congener. Conclusions: At the PCB concentrations measured in this cohort, which are high relative to most human populations today, we did not detect an association between maternal or early postnatal PCB exposure and specific antibody responses at 6-months of age. [Copyright &y& Elsevier]

Background: Polychlorinated biphenyls (PCBs) are ubiquitous environmental toxins. Although there is growing evidence to support an association between PCBs and deficits of neurodevelopment, the specific mechanisms are not well understood. The potentially different roles of specific PCB groups defined by chemical structures or hormonal activities e.g., dioxin-like, non-dioxin like, or anti-estrogenic PCBs, remain unclear. Our objective was to examine the association between prenatal exposure to defined subsets of PCBs and neurodevelopment in a cohort of infants in eastern Slovakia enrolled at birth in 2002-2004. Methods: Maternal and cord serum samples were collected at delivery, and analyzed for PCBs using highresolution gas chromatography. The Bayley Scales of Infant Development -II (BSID) were administered at 16 months of age to over 750 children who also had prenatal PCB measurements. Results: Based on final multivariate-adjusted linear regression model, maternal mono-ortho-substituted PCBs were significantly associated with lower scores on both the psychomotor (PDI) and mental development indices (MDI). Also a significant association between cord mono-ortho-substituted PCBs and reduced PDI was observed, but the association with MDI was marginal (p = 0.05). Anti-estrogenic and di-ortho-substituted PCBs did not show any statistically significant association with cognitive scores, but a suggestive association between di-ortho-substituted PCBs measured in cord serum and poorer PDI was observed. Conclusion: Children with higher prenatal mono-ortho-substituted PCB exposures performed more poorly on the Bayley Scales. Evidence from this and other studies suggests that prenatal dioxin-like PCB exposure, including mono-ortho congeners, may interfere with brain development in utero. Non-dioxin-like di-ortho-substituted PCBs require further investigation. [ABSTRACT FROM AUTHOR]

Background: Hydroxylated polychlorinated biphenyls (OH-PCBs), unlike PCBs, are in general readily excreted yet are still detected in humans and animals. Active transport of OH-PCBs across the placenta and hydroxylation of PCBs by the fetus suggest the potential for greater impact on the fetus compared with the parent PCB compounds, but little is known about their health effects, particularly in humans. Objectives: The objective of this study was to evaluate the associations between prenatal OH-PCB exposure and neurodevelopment in children at 16 months of age in eastern Slovakia. Methods: A birth cohort (n = 1,134) was enrolled during 2002-2004. We analyzed six OH-PCB metabolites (4-OH-CB-107, 3-OH-CB-153, 4-OH-CB-146, 3'-OH-CB-138, 4-OH-CB-187, and 4'-OH-CB-172) in a subset of the cohort. The Bayley Scales of Infant Development were administered to the children at the 16-month follow-up visit. We developed multiple linear regression models predicting standardized scores for the Mental Development Index (MDI) and Psychomotor Development Index (PDI) from maternal (n = 147) and cord (n = 80) serum OH-PCB concentrations, adjusting for sex of child, district, HOME (Home Observation for Measurement of the Environment) score, and maternal score on Raven's Progressive Matrices. Results: Cord 4-OH-CB-107 was significantly associated with lower MDI (β = -2.27; p = 0.01) and PDI (β = -4.50; p = 0.004). Also, maternal 4-OH-CB-107 was significantly associated with lower MDI (β = -1.76; p = 0.03) but not PDI. No other OH-PCB metabolites were associated with decreased PDI or MDI. Conclusions: Our findings showed a significant association of 4-OH-CB-107 with decreased MDI, which can possibly be mediated by endocrine disruption, altered neurotransmitter functions, or reduced thyroid hormone concentrations in brain. [ABSTRACT FROM AUTHOR]

Ingestion has been a primary route of PCB exposure for people, especially those not working directly in industrial settings. During 2002–2004, women were recruited at delivery from two districts in eastern Slovakia: Michalovce with high PCB contamination from a chemical manufacturing plant, and Svidnik located 70 km to the northwest, having lower environmental levels of PCBs. Concentrations of 15 PCB congeners were measured in maternal serum using high-resolution gas chromatography with electron capture detection. A food frequency questionnaire was developed and validated at the Research Institute of Nutrition and School of Medicine in Bratislava, Slovakia. The questionnaire was comprised of 88 food items representative of the national dietary habits and designed to ascertain (1) the source of food items as reported by the women (locally produced or purchased from a retail outlet) and (2) quantities consumed of high-fat food categories representative of the national dietary habits. Our primary goal was to identify specific food sources, either locally produced or purchased from retail stores, that might predict serum concentrations of PCBs. We used multiple linear regression to examine the relationship of dietary fats to lipid-adjusted serum PCB levels in 948 adult women (Michalovce N=662, Svidnik N=284) who had recently given birth. We adjusted for residential district, age, body mass index, education and duration of previous lactation. Consumption of fat from locally produced foods was significantly associated with higher levels of lipid-adjusted serum PCB (β=0.06, P=0.007). Fat from foods purchased in retail outlets showed no significant association (β=−0.02, P=0.36). There was no interaction between district and diet in predicting serum PCB levels. Comparing women in Michalovce consuming 20 g of fat per day from local sources with those consuming 1 g of fat per day from local sources, lipid-adjusted serum concentrations were predicted to be higher by 81 ng/g lipid or 14.8% 630 ng/g lipid versus 549 ng/g lipid.Journal of Exposure Science and Environmental Epidemiology (2008) 18, 581–587; doi:10.1038/jes.2008.1; published online 20 February 2008 [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCB) were widely used for industrial purposes and consumer products, but because of their toxicity, production was banned by most industrialised countries in the late 1970s. In eastern Slovakia, they were produced until 1985. During 2002–04, a birth cohort of mothers ( n = 1057) residing in two Slovak districts was enrolled at delivery, and their specimens and information were collected after birth. Congeners of PCBs were measured in maternal serum by high-resolution gas chromatography with electron capture detection. In this study, we used multiple linear regression to examine the effects of prenatal PCB exposure on birthweight adjusted for gestational age, controlling for inter-pregnancy interval, and maternal smoking, age, education, ethnicity, pre-pregnancy body mass index and height. The association between total maternal serum PCB levels and birthweight was not statistically significant. However, an interaction model indicated that maternal PCB concentrations were associated with lower birthweight in Romani boys. Based on the fitted regression model, the predicted birthweight of Romani boys at the 90th percentile of maternal PCBs (12.8 ng/mL) was 133 g lower than the predicted birthweight at the 10th percentile of maternal PCBs (1.6 ng/mL). This is a similar magnitude of effect to that observed for maternal smoking and birthweight. These results suggest that higher levels of PCBs in maternal blood sera may inhibit growth in boys, particularly in those already affected by social factors related to ethnicity. This study is consistent with previous findings that boys are more susceptible than girls to growth restriction induced by in utero organochlorine exposures, and further indicates that high PCBs may magnify the influence of social disadvantage in this vulnerable group of boys. [ABSTRACT FROM AUTHOR]

The aim of the present study was to understand the placental transfer of polychlorinated biphenyls (PCBs), specific hydroxylated PCB metabolites (OH-PCBs), and pentachlorophenol (PCP) in blood serum, in a birth cohort from eastern Slovakia. During the period 2002–2004, cord blood specimens were collected in parallel with maternal specimens from women delivering in the two eastern Slovak districts of Michalovce and Svidnik/Stropkov. A total of 92 pairs of mother-cord specimens at delivery were selected for this study. 4-OH-CB107, 3-OH-CB153, 4-OH-CB146, 3′-OH-CB138, 4-OH-CB187, and 4′-OH-CB172 were quantified. The median concentrations of Σ17PCBs, Σ6OH-PCBs, and PCP in cord serum were 0.92, 0.33, and 0.69ng/g wet wt., respectively and highly correlated with the corresponding maternal serum levels (correlations were R 2 =0.61, 0.78, and 0.82, respectively). The median cord to mother ratios of the Σ17PCBs, Σ6OH-PCBs, and PCP were 0.18, 0.75, and 1.10, respectively. The median ratio of the Σ6OH-PCBs to the Σ17 PCBs in the cord serum was 0.38 from wet weight based concentrations, which was about four times higher than the ratio of these compounds in maternal serum (0.09). PCP was more abundant than any PCB or OH-PCB congener measured in cord serum. The higher cord to maternal ratios of OH-PCB metabolites as compared with the parent compounds suggests either a higher placental transfer rate or greater metabolism in the fetus as compared with the maternal compartment. These findings are consistent with their preferential binding to TTR that can cross the placenta. The cord to maternal ratio varies by congener (e.g., 4-OH-CB107=0.58, 4-OH-CB146=0.74, 3′-OH-CB138=1.01). [Copyright &y& Elsevier]

Immune system development, particularly in the prenatal period, has far-reaching consequences for health during early childhood, as well as throughout life. Environmental disturbance of the complex balances of Th1 and Th2 response mechanisms can alter that normal development. Dysregulation of this process or an aberrant trajectory or timing of events can result in atopy, asthma, a compromised ability to ward off infection, or other auto-immune disease. A wide range of chemical, physical and biological agents appear to be capable of disrupting immune development. This MiniReview briefly reviews developmental milestones of the immune system in the prenatal period and early life, and then presents examples of environmentally induced alterations in immune markers. The first example involves a birth cohort study linked to an extensive programme of air pollution monitoring; the analysis shows prenatal ambient polycyclic aromatic hydrocarbons (PAH) and fine particle (PM2.5) exposures to be associated with altered lymphocyte immunophenotypic distributions in cord blood and possible changes in cord serum immunoglobulin E levels. The second example is a study of prenatal-polychlorinated biphenyl (PCB) exposures and the foetal development of the thymus, the organ responsible for lymphocyte maturation. Mothers with higher serum concentrations of PCBs gave birth to neonates having smaller indices of thymus size. Finally, this report underscores the tight connection between development of the immune system and that of the central nervous system, and the plausibility that disruption of critical events in immune development may play a role in neurobehavioural disorders. [ABSTRACT FROM AUTHOR]

BACKGROUND: Polychlorinated biphenyls (PCBs) are ubiquitous environmental toxicants, for which animal studies demonstrate immunotoxic effects, including thymic atrophy and suppressed immune responses; human investigations of similar end points are sparse. The thymus is essential for the differentiation and maturation of T-cell lymphocytes. OBJECTIVES: The objective of this study was to examine the association between prenatal PCB exposures and estimated thymus volume in infants from eastern Slovakia, a region where PCBs were produced until 1984. METHODS: Mothers were enrolled at delivery, and maternal blood samples were collected for analysis of 15 PCB congeners, p,p'-DDT [1,1,1-trichloro-2,2'-bis(p-chlorophenyl)ethane], and p,p'-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene]. Each mother was interviewed to obtain information on sociodemographic characteristics, past pregnancies, occupational history, medication history, and living environment. Neonatal thymus volume was estimated using ultrasound measurements on the third or fourth day after birth. Thymic index was calculated on 982 newborns from mothers with PCB measurements. We developed a predictive model of the natural log of the thymic index using multiple linear regression with covariates selected from the bivariate analyses. RESULTS: Prenatal PCB exposure was associated with a smaller thymic index at birth [β = -36 (natural log-transformed; nanograms per gram lipids); p = 0.047]. District of residence and delivery also predicted thymic index. Male sex, later gestational age, larger birth weight z-score, and Roma ethnicity were associated with a larger thymic index, whereas respiratory illness was associated with a lower thymic index. CONCLUSIONS: This study provides the first evidence to date that PCB exposure in neonates is associated with a smaller thymic volume, suggesting possible impaired immunologic development. [ABSTRACT FROM AUTHOR]

Abstract: Human breast milk represents the best choice for the nutrition of infants. It is often used for monitoring human exposures to environmental chemicals. Uniquely suited to meet human biological needs, breast milk composition, especially fat content, changes significantly with time from delivery. With the aim to compare the concentration of organochlorine compounds (OCs) in colostrum versus mature milk, we obtained samples of fourth–fifth day postpartum milk (colostrum) and day-14 postpartum milk (mature milk) from 12 women enrolled in the project “Early Childhood Development and PCB Exposure in Slovakia”. The concentrations of selected organochlorine pesticides and congeners of polychlorinated biphenyls (PCBs) were measured using gas chromatography with electron capture detection and reported on lipid adjusted basis. No significant differences were found between organochlorine levels in colostrum and those in mature milk samples. A very close correlation was found between the concentrations of organochlorine compounds in colostrum and mature milk (Spearman correlation coefficient r =0.94–0.98 for PCBs, and r =0.85–0.99 for organochlorine pesticides, p <0.001 for all compounds). The present study concludes that the use of colostrum samples provides a close estimate of the child’s exposure to OCs in the early neonatal period and demonstrates that, despite the lower fat content, colostrum specimens are adequate to conduct OC analyses. [Copyright &y& Elsevier]

OBJECTIVE: Our aim in the present study was to characterize and quantify the levels of polychlorinated biphenyls (PCBs) and specific polychlorobiphenylol (OH-PCB) metabolites in maternal sera from women delivering in eastern Slovakia. DESIGN: During 2002-2004, blood samples were collected from women delivering in two Slovak locations: Michalovce district, where PCBs were formerly manufactured, and Svidnik and Stropkov districts, about 70 km north. PARTICIPANTS: A total of 762 and 341 pregnant women were sampled from Michalovce and Svidnik/Stropkov, respectively, and OH-PCBs were measured in 131 and 31. EVALUATION/MEASUREMENTS: We analyzed PCBs using gas chromatography (GC)/electron capture detection. OH-PCBs and pentachlorophenol (PCP) were determined as methyl derivatives using GC-electron capture negative ionization/mass spectrometry. We characterized distributions in the full cohort using inverse sampling weights. RESULTS: The concentrations of both PCBs and OH-PCB metabolites of Michalovce mothers were about two times higher than those of the Svidnik/Stropkov mothers (p < 0.001). The median weighted maternal serum levels of the sum of PCBs (ΣPCBs) were 5.73 ng/g wet weight (Michalovce) and 2.82 ng/g wet weight (Svidnik/Stropkov). The median sum of OH-PCBs (ΣOH-PCBs) was 0.55 ng/g wet weight in Michalovce mothers and 0.32 ng/g wet weight in Svidnik/Stropkov mothers. 4-OH-2,2′,3,4′,5,5′,6-Heptachlorobiphenyl (4-OH-CB187) was a primary metabolite, followed 4-OH-2,2′,3,4′,5,5′-hexachlorobiphenyl (4-OH-CB146). Only four PCB congeners--CBs 153, 138, 180, and 170--had higher concentrations than 4-OH-CB187 and 4-OH-CB146 (p < 0.001). The median ratio of the ΣOH-PCBs to the ΣPCBs was 0.10. CONCLUSIONS: Mothers residing in eastern Slovakia are still highly exposed to PCBs, and their body burdens of these pollutants and OH-PCB metabolites may pose a risk for adverse effects on health for themselves and their children. [ABSTRACT FROM AUTHOR]

The over-riding aim of the present investigation was to obtain information concerning exposure that can be used as a basis for studies on the health of individuals residing in the Michalovce area of eastern Slovakia which is heavily contaminated by polychlorinated biphenyls (PCBs). Accordingly, this work focused on determination of serum concentrations of hydroxylated (OH-PCBs) and methylsulfonyl-substituted (MeSO2-PCBs) metabolites of PCBs. One hundred and twenty-two men and women, 20–59 years of age, living in the contaminated area and 175 from the control Stropkov/Svidnik district were selected randomly from 2047 sampled individuals. Following a specially designed cleanup, the levels of various congeners of OH-PCBs and MeSO2-PCBs in their serum were quantitated by gas chromatography and mass spectrometry, with comparison to authentic reference standards. The median concentrations of PCB congeners and their OH-PCB and MeSO2-PCB metabolites were 2–3-fold higher in residents of Michalovce than in the control region. The levels of certain OH-PCB metabolites were in the same high range as those of individual PCB congeners, whereas the MeSO2-PCB levels were significantly lower. The PCB and their metabolites were present at slightly higher concentrations in men than in women, and the serum levels of PCBs and MeSO2-PCBs increased with increasing age. Thus, the environmental contamination resulting from previous industrial production of PCBs has led to elevated concentrations of PCBs and their metabolites in the serum of individuals living in the Michalovce area. [ABSTRACT FROM AUTHOR]

Abstract: The gas phase polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs in the atmosphere of five European countries (Austria, the Czech Republic, Poland, Slovakia and Sweden) were measured simultaneously during two 21-day passive sampling campaigns using semipermeable membrane devices (SPMDs). SPMD samplers, consisting of a pair of SPMDs covered by a metal umbrella, were deployed at 40 locations ranging from remote and rural to urban and industrial, at a similar time during each of the two sampling campaigns (autumn 1999, except in Poland, winter 1999, and summer 2000). The total amounts of PAHs and nitro-PAHs found in the SPMDs ranged between 5.0–1.2×103 and 1.1×10−3–4.0ngSPMD−1 day−1, respectively. The measured environmental sampling conditions were similar between sites and, thus, the variations in the SPMD data reflected the spatial differences in gas phase concentrations of nitro-PAHs and PAHs within and between countries. The gas phase concentrations of nitro-PAHs and PAHs found in East Europe (Slovakia, the Czech Republic and Poland 1999) were 10 times higher than those measured in Sweden, Austria and Poland in 2000. In each country, the levels of PAHs and nitro-PAHs differed by one–three orders of magnitudes amongst sampling sites. The highest within-country spatial differences were found in Poland where levels of PAHs and nitro-PAHs were about one and two orders of magnitudes, respectively, higher in winter 1999 than in summer 2000, probably due to increasing emissions of coal combustion for residential heating. Differences in PAH-patterns between sites were visualized by the multivariate projection method, principal component analysis (PCA). However, no specific source patterns were found, probably since imissions rather than emissions were measured, so the PAHs detected at many sites originated from multiple sources. [Copyright &y& Elsevier]

In a population-based cross-sectional study, we compared serum levels of 15 polychlorinated biphenyl (PCB) congeners and three organochlorine pesticides in residents of two districts in eastern Slovakia, one with extensive environmental contamination from a former PCB production site (Michalovce) and the other matched on geography but with low (background) levels (Svidnik). The age-adjusted geometric means for sum of 15 measured PCB congeners were statistically significantly higher in subjects from the Michalovce district for both sexes: 3327.6 versus 1331.4 ng/g of lipid in males, 2751.8 versus 992.2 ng/g of lipid in females. Levels of DDE and DDT were also significantly higher, although the absolute differences were less pronounced. There was no substantial difference in HCB levels between the districts.We also conducted an ecologic study to compare cancer incidence occurring in these same two districts from 1985 through 1994. We calculated standardized incidence ratios (SIRs) and 95% confidence intervals for each district using indirect standardization and rates from eastern Slovakia. Among males from Michalovce (exposed), but not Svidnik (unexposed), there was an excess of cancer of the tongue (SIR=1.46; 1.06–1.96), stomach (SIR=1.15; 1.00–1.32), lung (SIR=1.14; 1.04–1.24), testis (SIR=1.40; 0.97–1.97), and kidney (SIR=1.23; 0.98–1.52), and lower than expected incidence of prostate cancer (SIR=0.83; 0.69–0.97); in contrast, there was an excess of peritoneal (SIR=3.05; 1.11–6.63) and laryngeal cancer (SIR=1.43; 0.99–1.98) in Svidnik not observed Michalovce. Among females from Michalovce, but not Svidnik, there was an excess of cancer of the lip (SIR=2.54; 1.53–3.96), stomach (SIR=1.22; 1.02–1.44), and lung (SIR=1.17; 0.94–1.45); in contrast, there was an excess of kidney (SIR=1.61; 1.03–2.40) and thyroid (SIR=1.97; 1.12–3.20) cancer in Svidnik not observed in Michalovce.Taken together, these results raise the possibility that high environmental exposure to organochlorines in the Michalovce district may be associated with higher rates of certain cancers, particularly stomach and lung cancer. [Copyright &y& Elsevier]

This case-control study was designed to investigate association between polychlorinated biphenyls (PCBs) and risk of breast cancer in an area of high environmental exposure in the Michalovce district of eastern Slovakia. Incident breast cancer cases from the Michalovce district diagnosed between May 1997 and May 1999 were recruited through the Oncology Department of the District Hospital. A total of 15 individual PCB congeners, 2,2'-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE), 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), and hexachlorobenzene (HCB) were measured in the serum of 24 breast cancer patients and 88 population controls in 1998-1999. The median levels of total PCBs were similar in cases (2586?ng/g of lipid) and controls (2682?ng/g of lipid). Higher serum levels (highest vs. lowest tertile) of total PCBs (odds ratio (OR)=0.42, 95% CI 0.10-1.82, p-for trend=0.31), group 1 congeners (OR=0.37, 95% CI 0.10-1.43, P-for trend=0.02), group 2 congeners (OR=0.32, 95% CI 0.07-1.56, P-for trend=0.60), and group 3 congeners (OR=0.49, 95% CI 0.12-2.04, P-for trend=0.51) were inversely associated with risk of breast cancer. Higher serum levels of DDE (OR=3.04, 95% CI 0.65-14.3, P-for trend=0.10) were positively associated with risk of breast cancer, while there was no association for DDT (OR=1.19, 95% CI 0.27-5.23, P-for trend=0.68), and an inverse association for HCB (OR=0.45, 95% CI 0.06-3.19, P-for trend=0.67). While generally not statistically significant, PCB and HCB levels were inversely associated with risk of breast cancer in this highly exposed population. DDE, but not DDT, was positively associated with risk.Journal of Exposure Analysis and Environmental Epidemiology (2003) 13, 267-275. doi:10.1038/sj.jea.7500277 [ABSTRACT FROM AUTHOR]