The influence of lipid and lifestyle factors upon correlations between highly prevalent organochlorine compounds in patients with exocrine pancreatic cancer

We aimed to analyse the influence of cholesterol and triglycerides, and of tobacco, coffee and alcohol consumption upon correlations between serum concentrations of organochlorine compounds (OCs) in patients with exocrine pancreatic cancer (EPC). Incident cases of EPC diagnosed in eastern Spain were prospectively identified (N=144). OCs were analysed by high-resolution gas chromatography with electron-capture detection. A strong correlation was observed between hexachlorobenzene (HCB) and beta-hexachlorocyclohexane (beta-HCH) (Spearman's rho=0.758). beta-HCH showed rho>0.4 with p,p'-DDT, p,p'-DDE, PCB138 and PCB153 (all p<0.001). Some correlations among compounds were slightly affected by tobacco, coffee or alcohol consumption. We observed a striking diversity of correlation patterns by strata of cholesterol and triglycerides. Most correlations were higher in the lowest category of triglycerides than in the lowest category of cholesterol. Most coefficients above 0.7 were seen in the lowest category of triglycerides (e.g., OC pairs p,p'-DDT and HCB, p,p'-DDT and beta-HCH, p,p'-DDE and beta-HCH, or HCB and beta-HCH). Correlations among OCs may be stronger when concentrations of triglycerides are low than when they are high. This is compatible with a dilution in the early phases of cancer and with a concentration effect as triglycerides become lower in the advanced phases of the disease.     

Effects of pre and postnatal exposure to low levels of polybromodiphenyl ethers on neurodevelopment and thyroid hormone levels at 4 years of age

There are at present very few studies of the effects of polybromodiphenyl ethers (PBDEs), used as flame retardants in consumer products, on neurodevelopment or thyroid hormone levels in humans. The present study aims to examine the association between pre and postnatal PBDE concentrations and neurodevelopment and thyroid hormone levels in children at age 4years and isolate the effects of PBDEs from those of PCBs, DDT, DDE and HCB. A prospective birth cohort in Menorca (Spain) enrolled 482 pregnant mothers between 1997 and 1998. At 4years, children were assessed for motor and cognitive function (McCarthy Scales of Children's Abilities), attention-deficit, hyperactivity and impulsivity (ADHD-DSM-IV) and social competence (California Preschool Social Competence Scale). PBDE concentrations were measured in cord blood (N=88) and in serum of 4years olds (N=244). Among all congeners analyzed only PBDE 47 was quantified in a reasonable number of samples (LOQ=0.002ng/ml). Exposure to PBDE 47 was analyzed as a dichotomous variable: concentrations above the LOQ (exposed) and concentrations below (referents). Scores for cognitive and motor functions were always lower in children pre and postnatally exposed to PBDE47 than in referents, but none of these associations was statistically significant (β coefficient (95%CI) of the total cognition score: -2.7 (-7.0, 1.6) for postnatal exposure, and -1.4 (-9.2, 6.5) for prenatal exposure). Postnatal exposure to PBDE 47 was statistically significantly related to an increased risk of symptoms on the attention deficit subscale of ADHD symptoms (RR (95%CI)=1.8 (1.0, 3.2)) but not to hyperactivity symptoms. A statistically significant higher risk of poor social competence symptoms was observed as a consequence of postnatal PBDE 47 exposure (RR (95%CI)=2.6 (1.2, 5.9)). Adjustment for other organochlorine compounds did not influence the results. Levels of thyroid hormones were not associated to PBDE exposure. This study highlights the importance of assessing the effects of PBDE exposure not just prenatally but also during the early years of life. In the light of current evidence a precautionary approach towards PBDE exposure of both mothers and children seems warranted.     

Prenatal exposure to organochlorine compounds and neuropsychological development up to two years of life

Polychlorinated biphenyls (PCB), hexachlorobenzene (HCB), and dichlorodiphenyl dichloroethylene (pp′DDE) are persistent, bioaccumulative, and toxic environmental pollutants with potential neurotoxic effects. Despite a growing body of studies investigating the health effects associated with these compounds, their specific effects on early neuropsychological development remain unclear. We investigated such neuropsychological effects in a population-based birth cohort based in three regions in Spain (Sabadell, Gipuzkoa, and Valencia) derived from the INMA [Environment and Childhood] Project. The main analyses in this report were based on 1391 mother–child pairs with complete information on maternal levels of organochlorine compounds and child neuropsychological assessment (Bayley Scales of Infant Development) at age 14 months. We found that prenatal PCB exposure, particularly to congeners 138 and 153, resulted in impairment of psychomotor development (coefficient = − 1.24, 95% confidence interval = − 2.41, − 0.07), but found no evidence for effects on cognitive development. Prenatal exposure to pp′DDE or HCB was not associated with early neuropsychological development. The negative effects of exposure to PCBs on early psychomotor development suggest that the potential neurotoxic effects of these compounds may be evident even at low doses.     

Organochlorine pesticide residues in sediments of a tropical mangrove estuary,India: implications for monitoring

The paper examines the concentrations of isomers of hexachlorocyclohexane (HCHs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), alpha-endosulfan and endosulfan sulfate in surface sediment samples collected from the mouth of Hugli estuary in the vicinity of Sundarban mangrove environment, eastern part of India. An overall pattern of accumulation of these pesticides was in the order of: SigmaHCH>endosulfan sulfate>SigmaDDT>alpha-endosulfan. The concentration of these compounds was quite low. An elevated level of SigmaHCH, SigmaDDT and endosulfan sulfate were marked during premonsoon months, a period characterized by high salinity and pH values. Among the isomers and metabolites of HCH and DDT, beta-HCH, pp'-DDT and pp'-DDE were found to be dominant. The sources of contamination are closely related to human activities, such as domestic and industrial discharges, agricultural chemical applications and soil erosion due to deforestation. The study is compared to other estuarine environment in India and abroad. The present data will serve as a baseline against which future anthropogenic effects may be assessed.     

Temporal trends in concentrations and total serum burdens of organochlorine compounds from birth until adolescence and the role of breastfeeding

Introduction: The aims of the present study are to assess the temporal trends of organochlorine compounds (OCs) concentrations and total serum burdens from birth until adolescence and the influence of breastfeeding in these temporal trends. Methods: In 1997 two birth cohort studies were set up in Ribera d'Ebre (N = 102) and the island of Menorca (N = 482), Spain. Concentrations (ng/mL) of OCs [pentachlorobenzene (PeCB), four isomers of hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (4,4′-DDT), dichlorodiphenyldichloroethylene (4,4′-DDE) and seven polychlorobiphenyl congeners (Σ₇PCBs)] were measured in cord blood and at the age of 4 and 14 years. The total serum burdens (ng) of these compounds were estimated based on the total blood volume (mL) of children at the different ages. We compared median concentrations and total serum burdens of these OCs at the different time-points of follow-up between children of Ribera d'Ebre and Menorca and between breastfed and non-breastfed children. Results: From birth until adolescence concentrations of all OCs drastically reduced. These reductions were mainly derived from the dilution of OCs, associated to an increase in total blood volume of children at the age of 4 and 14 years. Despite the reduction in OCs concentrations, the total serum burdens of 4,4′-DDE and Σ₇PCBs, were higher in adolescents than at birth. Increases in OCs total serum burden occurred both in breastfed and non-breastfed children, but were significantly higher in the first. Conclusions: Even after decades of banning OCs production and use, current young generations in westernized countries are still bioaccumulating these compounds. Given the potential health effects of OCs, especial attention should be paid in the control of secondary emissions in the environment and in the control of food production and contamination. In countries with endemic malaria it is important to work towards effective alternatives to the use of DDT.     

Organohalogenated pollutants in human serum from Iassy, Romania and their relation with age and gender

Human serum samples (n=142) from Iassy county (Eastern Romania) collected in 2005 were analyzed for p,p'-DDT and its metabolites, hexachlorobenzene, hexachlorocyclohexane (HCH) isomers, chlordane and metabolites and 14 polychlorinated biphenyl (PCB) congeners. In all samples, p,p'-DDE (principal metabolite of p,p'-DDT) and beta-HCH (most persistent HCH isomer) were the most abundant organochlorine pesticides (OCPs) with median concentrations of 1975 and 923 ng/g lipid weight (lw), respectively. Hexachlorobenzene and p,p'-DDT were also detected in all samples, but at a lower median concentration of 30 and 340 ng/g lw, respectively. The large variation of the ratio p,p'-DDT/p,p'-DDE (range between 0.02 and 0.80) suggests various degrees of exposure to DDT, including recent exposure, at least to some subgroups of the population. Chlordane and its metabolites were in most cases close to the limit of quantification suggesting a very low use of chlordane formulations in Eastern Romania. Unexpectedly, PCBs were present in all samples at sometimes considerable levels (up to 4970 ng/g lw for sum of 14 PCB congeners) indicating a higher exposure of the Romanian population than previously reported. The PCB profile consisted of persistent congeners such as 138, 153, 170 and 180 which contributed for approximately 75% to the sum PCBs. Concentrations of most pollutants correlated significantly with age (r>0.86, p<0.01). Except for p,p'-DDT and gamma-HCH, the mean levels of OCPs in females were statistically higher than in males, while, except for octa-CBs, no gender differences were found for PCBs. Levels of p,p'-DDE, penta-CBs, hexa-CBs and hepta-CBs were significantly higher in individuals with a rural main residence. In a pooled serum sample, 6 polybrominated diphenyl ether (PBDE) congeners were measured at a level of 1.04 ng/g lw. Compared to results available from Central and Eastern European countries, human serum samples from Romania contained higher levels of contamination. This emphasizes that an extensive and rigorous program for the monitoring of OCPs and PCBs in Romanian population is highly needed in the light of possible adverse health effects acknowledged for these pollutants.     

Association of serum concentration of organochlorine pesticides with dietary intake and other lifestyle factors among urban Chinese women

Concerns about the carcinogenic and endocrine-disrupting characteristics of organochlorine pesticides (OCPs) have led to a global ban on OCP use. However, OCPs persist in the environment for decades because of their long half-life. We evaluated serum levels of OCPs and their correlations with usual dietary intake and other lifestyle factors among 250 healthy women who participated as controls in the Shanghai Breast Cancer Study. Serum levels of hexachlorocyclohexane isomers (alpha-HCH, beta-HCH, gamma-HCH), dichloro-di-phenyl-trichloroethane (DDT) isomers (p,p'-DDE and p,p'-DDT), hexachlorobenzene (HCB), trans-nonachlor (TNC), and eight polychlorinated biphenyls (PCB) congeners (IUPAC no. 74, 118, 138, 153, 170, 180, 183, and 187) were measured. Lifestyle factors and usual dietary habits over the past 5 years were assessed through an in-person interview. With the exception of PCB, total OCP levels in our study population were significantly higher than those observed in other countries. Age, income, body mass index, waist-to-hip ratio, number of pregnancies, and/or total duration of breastfeeding were all significantly correlated with all types of OCPs. Of the 20 food groups evaluated, correlations with serum total OCPs were observed for eggs (r=0.13), fresh beans (r=-0.17), tea (r=0.14), and animal fat (r=0.18). Multiple regression analyses showed that age and animal fat intake were positively associated with serum total level OCPs, while leafy vegetable and fresh bean consumption was negatively associated with OCPs level. Our study suggests that dietary intake may be an important contributor of serum levels of OCPs in Chinese women.     

Prenatal exposure to PCB-153, p,p′-DDE and birth outcomes in 9000 mother–child pairs: Exposure–response relationship and effect modifiers

Low-level exposure to polychlorinated biphenyl-153 (PCB-153) and dichlorodiphenyldichloroethylene (p-p′-DDE) can impair fetal growth; however, the exposure–response relationship and effect modifiers of such association are not well established. This study is an extension of an earlier European meta-analysis. Our aim was to explore exposure–response relationship between PCB-153 and p-p′-DDE and birth outcomes; to evaluate whether any no exposure–effect level and susceptible subgroups exist; and to assess the role of maternal gestational weight gain (GWG). We used a pooled dataset of 9377 mother–child pairs enrolled in 14 study populations from 11 European birth cohorts. General additive models were used to evaluate the shape of the relationships between organochlorine compounds and birth outcomes. We observed an inverse linear exposure–response relationship between prenatal exposure to PCB-153 and birth weight [decline of 194 g (95% CI − 314, − 74) per 1 μg/L increase in PCB-153]. We showed effects on birth weight over the entire exposure range, including at low levels. This reduction seems to be stronger among children of mothers who were non-Caucasian or had smoked during pregnancy. The most susceptible subgroup was girls whose mothers smoked during pregnancy. After adjusting for absolute GWG or estimated fat mass, a reduction in birth weight was still observed. This study suggests that the association between low-level exposure to PCB-153 and birth weight exists and follows an inverse linear exposure–response relationship with effects even at low levels, and that maternal smoking and ethnicity modify this association.     

Organochlorine pesticide and polychlorinated biphenyl residues in feathers of birds from different trophic levels of South-West Iran

Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha, beta and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153 and 180), were determined in tail feathers from 37 birds belonging to 18 species, all originating from the South-West of Iran (Khuzestan, coast of the Persian Gulf). This is the first report on organochlorine contaminants in feathers from museum collections and it is an indication of the concentrations of OCPs and PCBs in the past (1991-1996). Median concentrations of HCHs, DDTs, PCBs and HCB were 22, 14, 11 and 10 ng/g feather, respectively. Significant correlations (p<0.05) were calculated between OCPs (except HCB) and PCBs in the bird feathers. p,p'-DDE and gamma-HCH were the most abundant OCPs, while CB 180, CB 138 and CB 101 were the predominant PCB congeners in almost all species. Significant differences (p<0.05) in the mean concentrations of DDTs and PCBs were detected among species grouped according to their feeding habits. Levels of DDTs and PCBs were highest in the carnivorous species and lowest in the herbivorous species. Levels of OCPs and PCBs in feathers of bids in the 1990s were generally below the thresholds reported to affect reproduction.     

Prenatal exposure to perfluorinated compounds affects thyroid hormone levels in newborn girls

Perfluorinated compounds (PFCs) are ubiquitous in the environment and have been detected in humans and wildlife. Exposure to PFCs has decreased in the United States recently, while exposure to PFCs continues in Asian countries, which represents a public health concern. Various mechanisms by which PFCs affect fetal growth have been proposed, such as activation of peroxisome proliferators, disruption of thyroid hormones and changes in lipid metabolism. However, the overall evidence for an association with thyroid hormones is not strong. Therefore, we examined the effect of various prenatal PFCs on cord blood thyroid hormones: triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH) levels, and explored the endocrine disrupting effect of these PFCs on thyroid hormone levels in children according to gender. Two hundred and seventy-nine study participants were selected from among the enrolled participants in the Ewha Birth & Growth Retrospective Cohort, a retrospective birth cohort study conducted at Ewha Womans University Hospital, Seoul, Korea between 2006 and 2010. A generalized linear model was constructed to explore the association of PFCs and thyroid hormones. Further, an analysis stratified by gender was conducted. Our study shows that cord blood perfluoro n-pentanoic acid (PFPeA) was positively associated with cord blood T4 (p = 0.01) level. Gender-specific analysis showed that prenatal PFCs: PFPeA and Perfluorohexane sulfonic acid (PFHxS) exposure significantly increased T4 (p < 0.01) and T3 (p = 0.03), respectively, while perfluorononanoic acid (PFNA) decreased TSH (p = 0.04) concentration in newborn girls. Thus, prenatal PFC exposure may disrupt thyroid hormone homeostasis. Thyroid hormones play a crucial role in fetal development and may have gender specific action. Hence, these results are of utmost importance in high-risk groups, such as pregnant women and children.     

The association between organochlorine and thyroid hormone levels in cord serum: a study from northern Thailand

It is now known that many organochlorines (OCs) act as endocrine disruptors, causing harmful effects on wildlife and humans. Several field and laboratory animal studies have reported that OCs cause adverse effects on thyroid hormone status. However, data regarding their effects on thyroid hormone status in humans are inconclusive. Because a developing fetus is especially sensitive to hormonal disruption by exposure to OCs, the adverse health effects on infants are of concern. The present study aimed to investigate the association between OC levels in maternal and cord serum, and the association between OC and thyroid hormone levels in cord serum. The study was performed with 39 mother-infant pairs from Mae Rim District of Chiang Mai Province, northern Thailand, who had normal delivery and full term gestation. Maternal blood was collected for measuring OCs and total lipids. Umbilical cord blood was collected for measuring OCs, total lipids, and thyroid hormones, including total thyroxine (TT(4)), free thyroxine (FT(4)), and thyroid stimulating hormone (TSH). 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (p,p'-DDE) had the highest level in all serum samples with a geometric mean of 1,191 ng/g lipids in maternal serum and 742 ng/g lipids in cord serum. The second highest level was that for 1,1,1-trichloro-2,2-di(4-chlorophenyl)ethane (p,p'-DDT), followed by 1,1-dichloro-2,2-di(4-chlorophenyl)ethane (p,p'-DDD). Levels of p,p'-DDE, p,p'-DDT, p,p'-DDD, and dieldrin in maternal serum were positively associated with levels in cord serum (r = 0.86, 0.77, 0.66, and 0.60, respectively; P<0.001). The important findings were that cord serum TT(4) levels were negatively associated with cord serum levels of p,p'-DDE (r = -0.37, P = 0.024), p,p'-DDT.3 (r = -0.33, P = 0.048), and 1,1-dichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethylene (o,p'-DDE) (r = -0.76, P = 0.019). These results therefore suggest that exposure to DDT and its metabolites during fetal development may cause some effects on thyroid hormonal status in infants.     

Occurrence and distribution of organochlorine pesticides - lindane, p,p'-DDT, and heptachlor epoxide - in surface water of China

Persistent organochlorine pesticides pollutants (OCPs) have been reported to occur at relatively high concentrations in some Chinese waters. In order to map the distribution of organochlorine pesticides in the surface water throughout China, samples were collected from over 600 sites in seven major river basins and three main internal rivers drainage areas during 2003 and 2004. The surface water samples were analyzed for the representative organochlorine pesticides contaminants including lindane (gamma-HCH), p,p'-DDT and heptachlor epoxide. In general, the most frequently detected compound was lindane, being detected in 83.9% of samples (mean=31.3 ng/l; range <0.17-860 ng/l), and the highest concentration was present in the Yellow River basin. p,p'-DDT was detected in 63.1% of the samples collected (mean=14.6 ng/l; range <0.14-368 ng/l) with the highest concentration present in the Huaihe River basin. Heptachlor epoxide was detected in only 9.3% of water samples (range <0.11-10 ng/l). Measured concentrations for the three compounds were low and rarely exceed the environment quality standard for surface water of China. Lindane was more frequently detected at much higher concentrations in the rivers of northern China compared with those of southern China. The sites with higher concentration of lindane and p,p'-DDT mainly occurred in the Yellow River and Huaihe River basins, so the results of this investigation indicate that the organochlorine pesticide contamination of Yellow River and Huaihe River basins should be of particular concern relative to the other basins. When compared with other regions of the world, it appears that the Chinese surface water is moderately polluted by lindane and p,p'-DDT.     

Levels of organohalogenated persistent pollutants in human milk from Kahramanmaraş region, Turkey

The levels of 1,1,1-trichloro-bis-2,2'-(4-chlorophenyl) ethane (p,p'-DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes (trans- and cis-chlordane, oxychlordane and trans-nonachlor), 11 polychlorinated biphenyl (PCB) congeners, and 7 polybrominated diphenyl ether (PBDE) congeners were measured in 37 individual human milk samples from Kahramanmara? region, Turkey. Organochlorine pesticides were the major contaminants in the milk samples. p,p'-DDE and p,p'-DDT were detected in all samples, while beta-HCH had a detection frequency of 97%. The sum of the DDTs in human milk samples varied between 0.52 and 315.8 ng/g wet weight (ww) with a mean ratio between p,p'-DDE and p,p'-DDT equal to 31.1. p,p'-DDD could be measured only in six samples. beta-HCH was the most prevalent HCH isomer with a mean value of 2.08 ng/g ww. The mean concentration of gamma-HCH was 0.38 ng/g ww, while alpha-HCH was not detected in any sample. HCB is found in 95% of the milk samples with a mean concentration of 0.30 ng/g ww. The mean value for the sum of chlordanes was 0.39 ng/g ww, with oxychlordane and trans-nonachlor being the principal contributors. PCBs could be measured only in 8 out of 37 samples and their concentration ranged between <0.15 and 1.92 ng/g ww for the sum of PCBs. PCB profiles were dominated by congeners 153, 180 and 138. PBDEs were detected only in 3 out of 37 samples, with the highest value being 0.014 ng/g ww (0.40 ng/g lipid weight) and BDE 47 was the dominant congener. Although the number of samples is relatively low and they are not representative for the whole Turkish population, the results of the present study are important to provide additional data on the concentrations of persistent organochlorinated pollutants in Turkey and show as first the PBDE levels in Turkish population.     

Organochlorine and heavy metals in newborns: Results from the Flemish Environment and Health Survey (FLEHS 2002–2006)

To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R² = 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R² = 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.     

Possible influence of lipid content on levels of organochlorine compounds in mussels from Galicia coast (Northwestern, Spain). Spatial and temporal distribution patterns

Influence of lipid content of mussel on levels of organochlorine compounds (polychlorinated biphenyls [PCBs] and OC pesticides) has been studied. Mussel samples coming from three sites in Galicia coast (Northwestern, Spain), Moa?a and Cangas C from Ría de Vigo and Barallobre from Ría de Ferrol, collected monthly in the period from November 2000 to October 2001, have been analysed. Organochlorine compounds, PCBs (IUPAC nos. 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180) and OC pesticides (pp'-DDE, op'-DDT, pp'-DDT, aldrin, isodrin and endrin) have been extracted by means of Soxhlet and determined by using gas chromatography (electron capture detector [ECD]) and gas chromatography-mass spectrometry. Statistical analysis has been performed using the SPSS statistical package. Few compounds were correlated with lipid content (Pearson product-moment correlation); for samples coming from Barallobre, only the individual PCBs 31, 28, 52 (tri- and tetrachlorinated biphenyls) and 180 (heptachlorinated biphenyl) presented a significant correlation; for Moa?a samples, two cyclodiene pesticides, endrin and isodrin, presented a slight significant correlation with lipid content. From these results, it is deduced that the normalization of the concentration of organochlorine compounds to the lipid content is not necessary, in this way, avoiding possible error sources associated to the analytical determination of the lipid contentor reproductive status of mussel. Multivariate techniques (PCA) have been employed in order to study spatial and temporal distribution patterns of organochlorine compounds. The great differences found in studied samples are mainly related to spatial distribution: separations between estuarine bays (samples coming from Ría de Vigo and Ría de Ferrol) and between rural and urban zones (samples coming from Moa?a and Cangas C and samples from Barallobre, respectively).     

Brominated flame retardants and other organochlorine pollutants in human adipose tissue samples from the Czech Republic

Brominated flame retardants (BFRs) represented by polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) together with major persistent organochlorine pollutants, polychlorinated biphenyls (PCBs) and selected organochlorine pesticides (OCPs), were determined in adipose tissue samples (n=98) obtained by liposuction of Czech subjects. Compared to other organochlorine pollutants (mostly PCBs and DDTs), levels of PBDE were lower by 2 orders of magnitude ranging from 0.2 to 54.3 ng/g lipid weight. PBDE congeners No. 47, 99, 153 and 183 were the most abundant constituting up to 90% of these pollutants in adipose tissue. The PBDEs content measured in this study was comparable with data reported in similar samples collected in Spain, Sweden, Belgium and Japan, whilst slightly lower than in the United States. Regarding PCBs, the dominating congeners were No. 138, 153 and 180 representing up to 90% of indicator congeners. The levels of PCBs were similar to those found in other European countries. While no age dependency was found for PBDEs, an increase of PCB and OCP levels with age was observed. Different exposure routes of donors were documented by the absence of the relationship between PCBs and OCPs.     

Persistent organochlorine compounds in peregrine falcon (Falco peregrinus) eggs from South Greenland: levels and temporal changes between 1986 and 2003

Thirty-seven addled peregrine falcon eggs collected in South Greenland between 1986 and 2003 were analysed for their content of the organochlorine compounds polychlorinated biphenyls (PCBs), dichlorodiphenyl tricloroethane (DDT) and its degradation products, hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB). PCBs and DDT (including metabolites) were by far the most abundant OC groups, with median concentrations of 55 and 40 microg/g lw, respectively. The concentrations were high in an Arctic context, but similar to previously reported levels from Alaska and Norway and slightly lower than concentrations measured in eggs from industrialised regions. Geographical differences may be of importance, considering the migration of peregrine falcons and their prey. SigmaHCH and HCB had median concentrations of 0.39 and 0.17 microg/g lw, respectively. On average, DDE accounted for 97% of SigmaDDT, but was below critical levels for eggshell thinning. All compound groups showed a weak decreasing trend over the study period, which was statistically significant for HCB and close to being significant for SigmaHCH. The weak decrease of SigmaPCB and SigmaDDT is different from other time trend studies from Greenland, usually showing a more pronounced decrease in the beginning of the study period, followed by a certain stabilisation in recent years.     

Persistent organic pollutants exposure during pregnancy,maternal gestational weight gain,and birth outcomes in the mother–child cohort in Crete,Greece (RHEA study)

BackgroundPersistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and pesticides bioaccumulate through the food chain and cross the placenta. POPs are developmental toxicants in animals but the epidemiological evidence on pregnancy outcomes is inconsistent. Maternal gestational weight gain has been recently suggested as a key factor explaining the association between PCBs with lower birth weight.AimsWe examined whether in utero exposure to current low levels of different POPs is associated with fetal growth and gestational age in a mother–child cohort in Crete, Greece (Rhea study), and evaluated specifically whether maternal gestational weight gain may affect this association.MethodsWe included 1117 mothers and their newborns from the Rhea study. Mothers were interviewed and blood samples collected during the first trimester of pregnancy. Information on birth outcomes was retrieved from medical records. Concentrations of several PCBs, other organochlorine compounds (dichlorodiphenyl dichloroethene [DDE], dichlorodiphenyl trichloroethane [DDT] and hexachlorobenzene [HCB]) and one polybrominated diphenyl ether congener (tetra-bromodiphenyl ether [BDE-47]), were determined in maternal serum by triple quadrupole mass spectrometry. Multiple linear regression models were used to investigate the associations of birth weight, gestational age, and head circumference with each compound individually on the log₁₀ scale, and with combined exposures through the development of an exposure score.ResultsIn multivariate models, birth weight was negatively associated with increasing levels of HCB (β = − 161.1 g; 95% CI: − 296.6, − 25.7) and PCBs (β = − 174.1 g; 95% CI: − 332.4, − 15.9); after further adjustment for gestational weight gain these estimates were slightly reduced (β = − 154.3 g; 95% CI: − 300.8, − 7.9 for HCB and β = − 135.7 g; 95% CI: − 315.4, 43.9 for PCBs). Furthermore, in stratified analysis, the association between POPs and birth weight was only observed in women with inadequate or excessive gestational weight gain. Small, negative associations were observed with head circumference while no association was observed with gestational age.ConclusionsThe findings suggest that prenatal exposure to PCBs and HCB impairs fetal growth and adds to the growing literature that demonstrates an association between low-level environmental pollutant exposure and fetal growth. Furthermore our results suggest that the association of POPs, maternal gestational weight gain and birth weight is probably more complex than that previously hypothesized.     

Organochlorine levels in edible fish from the Marmara Sea, Turkey

Samples of 12 edible fish species from the Marmara Sea were analyzed for organochlorines (PCBs, DDTs, HCB, HCHs, toxaphene, etc.). The results showed that the total concentrations ranged from 329.41 ng/g fat to 1453.87 ng/g fat. DDT group components made up almost half or more of organochlorine contamination. Levels in red mullet were compared with those from neighbor seas. The sum of DDTs as well as HCHs concentrations were markedly lower than in the Black Sea but higher in the Aegean Sea and Mediterranean. Thus, inflow from the Black Sea might be considered as a contamination source for DDT and HCH contamination. On the other hand, total PCB concentration (sum of congeners 28, 52, 101, 118, 138, 153 and 180) detected in this study was comparable or lower than those from the Aegean Sea and Mediterranean. Toxaphene was a minor contaminant. Measured values were below maximum residue levels for human consumption.     

Persistent organic pollutants (PCBs and DDTs) in small size specimens of bluefin tuna (Thunnus thynnus) from the Mediterranean Sea (Ionian Sea)

The concentration levels and pattern distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides (DDTs), were investigated in liver of small size specimens of bluefin tuna (Thunnus thynnus) from Mediterranean Sea (Ionian Sea). PCB concentrations (average: 526 ng g(-1) lipid wt) were comparable with DDT levels (average: 435 ng g(-1) lipid wt). The specific analysis of PCB congeners revealed a profile dominated by hexa-, penta- and heptachlorinated congeners, while among DDTs, the compounds with the higher concentration was p,p'-DDE, constituting 91.9% of the total DDT. The total 2,3,7,8-TCDD toxic equivalent (TEQs) of coplanar PCBs, including mono- and non-ortho congeners, was 0.55 pg g(-1) wet weight with. The congeners with highest TEQs values were non-ortho congeners followed by mono-ortho ones.