Sociodemographic, reproductive and dietary predictors of organochlorine compounds levels in pregnant women in Spain

Serum and adipose tissue as matrices for assessment of exposure to persistent organic pollutants in breast cancer patients

The aim of this study was to assess differences between two biological matrices (serum and breast adipose tissue) in the evaluation of persistent organic pollutant (POP) exposure in breast cancer patients. The study population consisted of 103 women undergoing surgery for newly diagnosed breast carcinoma in a public hospital in Granada, Southern Spain. Independent variables were gathered from questionnaires and clinical records. POP concentrations were quantified in breast adipose tissue and serum samples. Spearman correlation tests were performed between pairs of POP concentrations and stepwise multivariable linear regression analyses were conducted to assess predictors of concentrations in the two matrices. p,p'- Dichlorodiphenyldichloroethylene (p,p'-DDE) showed the the highest median concentration in both matrices (194.34 and 173.84 ng/g lipid in adipose tissue and serum, respectively). Median wet-basis adipose tissue:serum ratios ranged from 109.34 to 651.62, while lipid-basis ratios ranged from 0.88 to 4.34. In general, we found significant positive correlation coefficients between pairs of POPs in adipose tissue and in serum, which were always higher in adipose tissue. We found positive and statistically significant correlations between serum and adipose tissue concentrations of p,p'-DDE and hexachlorobenzene (HCB) but not of polychlorinated biphenyls (PCBs). Age was positively associated with most POPs in adipose tissue and serum, while the body mass index was positively associated with adipose tissue HCB concentrations and negatively associated with serum PCB-153 and PCB-138 concentrations. Recent weight loss was inversely associated with POP residues in adipose tissue and positively associated with POP residues in serum. Serum HCB and PCB-180 concentrations were lower in patients who had received preoperative chemotherapy. According to our results, serum and adipose tissue POP concentrations in breast cancer patients may be differentially affected by external predictors. Taken together, these findings indicate the need to take account of the individual POP(s) under study and the biological matrix used when relating internal POP exposure to breast cancer disease and to make a careful selection of covariates for adjusting the model.

Concentrations of Persistent Organic Pollutants in California Children's Whole Blood and Residential Dust

We evaluated relationships between persistent organic pollutant (POP) levels in the blood of children with leukemia and POP levels in dust from their household vacuum cleaners. Blood and dust were collected from participants of the California Childhood Leukemia Study at various intervals from 1999 to 2007 and analyzed for two polybrominated diphenyl ethers (PBDEs), two polychlorinated biphenyls (PCBs), and two organochlorine pesticides using gas chromatography-mass spectrometry. Due to small blood sample volumes (100 μL), dichlorodiphenyldichloroethylene (DDE) and BDE-153 were the only analytes with detection frequencies above 70%. For each analyte, depending on its detection frequency, a multivariable linear or logistic regression model was used to evaluate the relationship between POP levels in blood and dust, adjusting for child's age, ethnicity, and breastfeeding duration; mother's country of origin; household annual income; and blood sampling date. In linear regression, concentrations of BDE-153 in blood and dust were positively associated; whereas, DDE concentrations in blood were positively associated with breastfeeding, maternal birth outside the U.S., and Hispanic ethnicity, but not with corresponding dust-DDE concentrations. The probability of PCB-153 detection in a child's blood was marginally associated with dust-PCB-153 concentrations (p = 0.08) in logistic regression and significantly associated with breastfeeding. Our findings suggest that dust ingestion is a source of children's exposure to certain POPs.

Demographic, behavioral, dietary, and socioeconomic characteristics related to persistent organic pollutants and mercury levels in pregnant women in Japan

Persistent organic pollutants and mercury are known environmental chemicals that have been found to be ubiquitous in not only the environment but also in humans, including women of reproductive age. The purpose of this study was to evaluate the association between personal lifestyle characteristics and environmental chemical levels during the perinatal period in the general Japanese population. This study targeted 322 pregnant women enrolled in the Hokkaido Study on Environment and Children's Health. Each participant completed a self-administered questionnaire and a food-frequency questionnaire to obtain relevant information on parental demographic, behavioral, dietary, and socioeconomic characteristics. In total, 58 non-dioxin-like polychlorinated biphenyls, 17 dibenzo-p-dioxins and -dibenzofuran, and 12 dioxin-like polychlorinated biphenyls congeners, perfluorooctane sulfonate, perfluorooctanoic acid, and mercury were measured in maternal samples taken during the perinatal period. Linear regression models were constructed against potential related factors for each chemical concentration. Most concentrations of environmental chemicals were correlated with the presence of other environmental chemicals, especially in the case of non-dioxin-like polychlorinated biphenyls and, polychlorinated dibenzo-p-dioxins and -dibezofurans and dioxin-like polychlorinated biphenyls which had similar exposure sources and persistence in the body. Maternal smoking and alcohol habits, fish and beef intake and household income were significantly associated with concentrations of environmental chemicals. These results suggest that different lifestyle patterns relate to varying exposure to environmental chemicals.

Exposure to fine particle matter, nitrogen dioxide and benzene during pregnancy and cognitive and psychomotor developments in children at 15 months of age

BACKGROUND

Prenatal exposure to air pollutants has recently been identified as a potential risk factor for neuropsychological impairment.

OBJECTIVES

To assess whether prenatal exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2) and benzene were associated with impaired development in infants during their second year of life.

METHODS

Regression analyses, based on 438 mother-child pairs, were performed to estimate the association between mother exposure to air pollutants during pregnancy and neurodevelopment of the child. The average exposure to PM2.5, NO2 and benzene over the whole pregnancy was calculated for each woman. During the second year of life, infant neuropsychological development was assessed using the Bayley Scales of Infant Development. Regression analyses were performed to estimate the association between exposure and outcomes, accounting for potential confounders.

RESULTS

We estimated that a 1 μg/m(3) increase during pregnancy in the average levels of PM2.5 was associated with a -1.14 point decrease in motor score (90% CI: -1.75; -0.53) and that a 1 μg/m(3) increase of NO2 exposure was associated with a -0.29 point decrease in mental score (90% CI: -0.47; -0.11). Benzene did not show any significant association with development. Considering women living closer (≤ 100 m) to metal processing activities, we found that motor scores decreased by -3.20 (90% CI: -5.18; -1.21) for PM2.5 and -0.51 (-0.89; -0.13) for NO2, while mental score decreased by -2.71 (90% CI: -4.69; -0.74) for PM2.5, and -0.41 (9% CI: -0.76; -0.06) for NO2.

CONCLUSIONS

Our findings suggest that prenatal residential exposure to PM2.5 and NO2 adversely affects infant motor and cognitive developments. This negative effect could be higher in the proximity of metal processing plants.

Time trends in serum organochlorine pesticides and polychlorinated biphenyls in the general population of Biscay, Spain

Despite the measures adopted, levels of organochlorine compounds (OCs) are still being detected in the human body. This study aimed to explore factors related to changes in the concentrations of polychlorinated biphenyls (PCBs) and pesticide OCs in blood samples obtained from a general population cohort. Two cross-sectional samples were taken from 162 adults (2-75 years of age), with a gap of 2 years, from four areas in Biscay (Spain). More than 75 % had quantifiable levels of hexachlorobenzene (HCB), beta-hexachlorocyclohexane (β-HCH), dichlorodiphenyldichloroethylene, and PCBs 138 153 and 180. During this time, significant changes were observed: PCB 180 and HCB levels increased, and PCB 138 and β-HCH levels decreased. Regarding age, this study shows a decrease suggesting a cohort effect. The period was not related to the decrease of levels in all age intervals, but a statistically significant increase of PCBs in older people was found. High body mass index was associated with lower PCB 180 levels and greater HCH levels. Inversely, greater levels of HCB and β-HCH were in those who had lost weight before the study. Levels of HCB and β-HCH were also greater in women who had had children, although they were lower in those who breastfed. Levels of these same OCs were greater in fish consumers, whereas those of PCBs 138 and 153 were greater in those who consumed local produce; all of these trends were close to significance. Efforts should continue to decrease exposure to these pollutants and to assess their influence on general population.

Serum levels of persistent organic pollutants and predictors of exposure in Tunisian women

INTRODUCTION

In spite of the international consensus on the human health risks associated with exposure to persistent organic pollutants (POPs), the Tunisian population is suspected to have been inadvertently exposed to POPs over the last decades.

OBJECTIVES

The aim of this study was to evaluate POP concentrations in the serum of a subset of 54 Tunisian women and to identify some socio-demographic and dietary predictors of exposure to POPs.

RESULTS

Of the ten POPs analyzed, three polychlorinated biphenyl (PCB) congeners (-138, -153 and -180), and two organochlorine pesticides (OCPs), HCB and p,p'-DDE, showed frequencies ranging from 98 to 100%. Serum median concentrations of PCB congeners (-138, -153 PCB-180) were 26.08, 119.1 and 29.84 ng/g lipid, respectively, and median concentrations of HCB and p,p'-DDE were 19.98 and 127.59 ng/g lipid, respectively. Age was positively correlated with serum levels of selected POPs. Women living in northern Tunisia showed higher serum levels of all PCBs. Working outside home and cereal consumption were positively associated to serum levels of p,p'-DDE. The duration of the lactation was also related to lower serum levels of p,p'-DDE and HCB.

CONCLUSION

The levels of exposure to POPs found warrant a biomonitoring program in order to identify routes of exposure and population groups at higher risk. This program will help to establish prevention policies and to determine the association between exposure to POPs and chronic diseases.

Study on polychlorobiphenyl serum levels in French consumers of freshwater fish

INTRODUCTION

Polychlorobiphenyls (PCBs) are persistent pollutants that are widespread in the environment and in foodstuffs, particularly in freshwater fish, which frequently exceed the maximum levels set by European regulations.

OBJECTIVES

First, we describe the consumption of freshwater fish and serum PCB levels in French anglers, a population expected to have the highest level of dietary PCB exposure. Second, we investigated whether there is a statistical relationship between serum PCB levels and the angler consumption of freshwater fish with high PCB bioaccumulation potential (PCB-BP(+) freshwater fish) in order to make recommendations with regard to safe consumption of freshwater fish.

METHODS

We conducted a survey of anglers from six sites with contrasting PCB contamination levels. The survey included a food consumption frequency questionnaire and blood samples were taken to assess serum PCB levels. We used a regression model to determine the main factors contributing to serum PCB levels.

RESULTS

Consumption of PCB-BP(+) freshwater fish was relatively infrequent. Serum PCB levels of the study population and of women of childbearing age were in the same range as those observed in the French population and in neighbouring European countries, but higher than in the North American population. The two factors with the highest positive association with serum PCB levels were age (R(2)=61%) and the consumption of PCB-BP(+) freshwater fish (R(2)=2%). Using the regression model, we calculated, for several scenarios depending on the age and gender of the population, the maximum annual frequencies for PCB-BP(+) freshwater fish consumption that do not exceed the critical body burden threshold.

CONCLUSION

Following the results of this study, the French agency for food, environmental and occupational health and safety (ANSES) issued an opinion and recommended some specific maximum freshwater fish consumption frequencies to protect the French general population.

Relationship between serum concentrations of persistent organic pollutants and markers of insulin resistance in a cohort of women with a history of gestational diabetes mellitus

The aim of the present study was to assess the relationship between serum concentrations of several persistent organic pollutants and insulin resistance markers in a cohort of women with a history of gestational diabetes mellitus. ∑POPs was computed as the sum of individual serum POP concentrations. No statistically significant associations were found between levels of any POP and fasting glucose. However, polychlorinated biphenyl (PCB) congeners 138 and 180 were positively associated with 2-h glucose levels and PCB 180 also with fasting immunoreactive insulin (IRI). We also found a positive association of p,p'- dichlorodiphenyldichloroethylene (p,p'- DDE), PCBs (138, 153, and 180), hexachlorobenzene, and ∑POPs with 2-h IRI. Serum concentrations of PCBs (138, 153, and 180), hexachlorobenzene, and ∑POPs were also positively associated with homeostasis model assessment (HOMA2-IR) levels. Moreover, p,p'- DDE, PCBs (138, 153 and 180), hexachlorobenzene, and ∑POPs were negatively associated with Insulin Sensitivity Index (ISI-gly) levels. No significant association was found between glycated hemoglobin and the concentrations of any POP. The removal of women under blood glucose lowering treatment from the models strengthened most of the associations previously found for the whole population. Our findings suggest that exposure to certain POPs is a modifiable risk factor contributing to insulin resistance.

Concentrations of persistent organic pollutants in California women's serum and residential dust

BACKGROUND

Humans are exposed to persistent organic pollutants (POPs) through various routes, including consumption of contaminated food and accidental ingestion of settled dust.

OBJECTIVES

We aimed to identify key routes of exposure to organochlorine pesticides, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in California women of reproductive age.

METHODS

Blood was collected from 48 mothers participating in the California Childhood Leukemia Study from 2006 to 2007 and analyzed for POPs using gas chromatography-mass spectrometry. Multivariable linear regression models of natural-log transformed serum concentrations were used to identify determinants of exposure from available questionnaire information on dietary habits, reproductive history, and demographic characteristics, as well as vacuum cleaner dust-POP levels.

RESULTS

After adjusting for blood lipid levels, age, body mass index, cumulative lactation, and sampling date, serum concentrations of multiple major PCBs were positively associated with fish consumption, but not dust-PCB levels. After adjusting for blood lipid levels, Hispanic ethnicity, country of origin, and household annual income, serum concentrations of multiple major PBDEs were positively associated with dust-PBDE levels.

CONCLUSIONS

Our findings suggest that the relative contribution of specific exposure routes to total POP intake varies by chemical class, with dust being a relatively important source of PBDEs and diet being a relatively important source of PCBs.

Organochlorine pesticide residues in breast milk and maternal psychopathologies and infant growth from suburban area of Ankara, Turkey

We aimed to determine the levels of organochlorine pesticides (OCPs) in the breast milk; to assess the effect of detectable OCPs on maternal-infant characteristics and; to evaluate the relation between OCPs and the maternal psychopathologies [Brief Symptom Inventory (BSI), Postpartum Bonding Questionnaire (PBQ), Mother-to-Infant Bonding Scale (MIBS) and Edinburgh Postnatal Depression Scale (EPDS)] and infant growth. DDT, beta-hexachlorocyclohexane (HCH), aldrin and heptachlor were detected in 89.3, 70.7, 58.7 and 34.7 % of the samples, respectively. Mothers with low monthly family income had detectable DDTs less frequently. The frequencies of detectable heptachlor epoxide were significantly higher in mothers with gestational nausea. Anaemic mothers had more frequently detectable alpha-HCH. Z scores of head circumference were inversely correlated with beta-HCH and DDT levels. The heptachlor epoxide levels were positively correlated with PBQ, MIBS and indexes of BSI. No relation was detected between EPDS and OCPs. Further studies are needed for changes in maternal psychopathologies.

Polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyldichloroethylene (DDE) concentrations in maternal and umbilical cord serum in a human cohort from South Portugal

Organochlorine compounds as polychlorinated biphenyls (PCBs) and pp'-dichlorodiphenyldichloroethylene (pp'DDE) are ubiquitous, resistant to degradation and lipophilic compounds, commonly found in the general population. Prenatal exposure to these compounds has been associated to adverse developmental effects. Levels of PCBs and pp'DDE were investigated in maternal and umbilical cord serum of 68 women/newborns pairs from Algarve, South Portugal. Mean sum PCBs congeners and pp'DDE concentrations were 1.62 ± 0.39 ng mL(-1)and 1.11 ± 0.69 ng mL(-1)-for maternal and 1.45 ± 0.25 ng mL(-1) and 0.85 ± 0.50 ng mL(-1)for cord serum, respectively. Congeners distribution pattern followed the order PCB 153>180>130, both for maternal and cord serum). Significant correlations (p<0.05) were found between maternal and cord serum concentrations. The umbilical cord/maternal serum ratio were 0.90 and 0.76, respectively for ΣPCB and pp'DDE Multivariate analyses relate women in urban centers with higher PCB levels, while higher pp'DDE relates to older primiparous women that live at rural areas. PCBs were also correlated to more portions of fat rich foods, while pp'DDE is associated to higher ingestion of vegetables and fruits. Smoking habits only correlated to maternal PCB. The present work provides, to our knowledge and for the first time, baseline human-biomonitoring data and establishes background ranges of PCB and pp'DDE levels in the maternal and umbilical cord serum in the Algarve region. These compounds exhibited the capacity to pass the placenta barrier and target the fetus. Even in non-industrialized areas, and in non-intensive agriculture areas, like the Southern Portugal, there is a need to take measures to eliminate or minimize the risk of organochlorine exposure during pregnancy.

Chlorinated persistent organic pollutants, obesity, and type 2 diabetes

Persistent organic pollutants (POPs) are lipophilic compounds that travel with lipids and accumulate mainly in adipose tissue. Recent human evidence links low-dose POPs to an increased risk of type 2 diabetes (T2D). Because humans are contaminated by POP mixtures and POPs possibly have nonmonotonic dose-response relations with T2D, critical methodological issues arise in evaluating human findings. This review summarizes epidemiological results on chlorinated POPs and T2D, and relevant experimental evidence. It also discusses how features of POPs can affect inferences in humans. The evidence as a whole suggests that, rather than a few individual POPs, background exposure to POP mixtures-including organochlorine pesticides and polychlorinated biphenyls-can increase T2D risk in humans. Inconsistent statistical significance for individual POPs may arise due to distributional differences in POP mixtures among populations. Differences in the observed shape of the dose-response curves among human studies may reflect an inverted U-shaped association secondary to mitochondrial dysfunction or endocrine disruption. Finally, we examine the relationship between POPs and obesity. There is evidence in animal studies that low-dose POP mixtures are obesogenic. However, relationships between POPs and obesity in humans have been inconsistent. Adipose tissue plays a dual role of promoting T2D and providing a relatively safe place to store POPs. Large prospective studies with serial measurements of a broad range of POPs, adiposity, and clinically relevant biomarkers are needed to disentangle the interrelationships among POPs, obesity, and the development of T2D. Also needed are laboratory experiments that more closely mimic real-world POP doses, mixtures, and exposure duration in humans.

Serum levels of organochlorine pesticides in the French adult population: the French National Nutrition and Health Study (ENNS), 2006-2007

BACKGROUND

Although most organochlorine (OC) pesticides were banned in France in the 1970s and 1980s, they remain a source of public concern. Because of their high persistence in the environment, they are still detected in foodstuffs, leading to continued human exposure. The purpose of this study was to assess the distribution of serum organochlorine (OC) pesticides in the French adult population and to identify the main risk factors for p,p'-dichlorodiphenyl dichlorethylene (DDE), β-hexachlorocyclohexane (β-HCH) and hexachlorobenzene (HCB).

METHOD

The selected OC pesticides (HCB, DDE, DDT, α-HCH, β-HCB and γ-HCH) were measured in serum samples collected in 2006-2007 from 386 persons (aged 18-74 years) randomly selected among the participants in the clinical and biological component of the French Nutrition and Health Survey (Etude Nationale Nutrition Santé [ENNS]), a cross-sectional survey carried out in the general population. Collected data included biological samples, socio-demographic characteristics, and data about environmental and occupational exposure factors.

RESULTS

Of the six OC pesticides investigated, the highest concentrations were observed for HCB, β-HCH and DDE. Median serum concentrations were as follows: 22.8 ng/g lipid for HCB, 0.74 and 27.0 ng/g lipid, respectively, for α- and ß-HCH, and 3.8 and 104.6 ng/g lipid, respectively, for DDT and DDE. Lindane (γ-HCH) was detected in approximately 10% of the sample. OC pesticide levels in serum in French adults were higher (except for DDT and DDE) than those observed in American, Canadian and German populations and generally lower than or in the same range as those observed in other European countries. The low serum DDT/DDE ratio in the present study (3.7%) would suggest that the concentrations observed for these two OC pesticides were mainly the result of past exposure. The most important predictors of serum DDE, HCB and β-HCH concentrations among the French adult population included individual factors (age, gender, BMI, etc.), dietary factors of animal and vegetable origin, and domestic use of pesticides (in vegetable gardens and/or fruit trees).

CONCLUSION

For the first time in France, a human biomonitoring study has shown that exposure to OC pesticides remains common in the population. French concentrations were higher (except for DDT and DDE) or were similar to those observed in other developed countries.

Prenatal exposure to persistent organic pollutants and rapid weight gain and overweight in infancy

OBJECTIVE

To examine the effects of prenatal exposure to persistent organic pollutants (POPs) on rapid growth in the first 6 months of life and overweight at 14 months of age.

DESIGN AND METHODS

In a Spanish birth cohort study, the POPs dichlorodiphenyldichloroethylene (DDE), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs-congeners 153, 138, 180) were measured in maternal serum collected in the first trimester of pregnancy during 2003-2008. Rapid growth was defined as a z-score weight gain >0.67 SD between 6 months of age and birth. Overweight at 14 months was defined as a BMI z-score ≥85th percentile. Generalized linear models examined the association between POPs and rapid growth (N = 1285) and overweight (N = 1198).

RESULTS

The analysis population included 24% rapid growers and 30% overweight infants. DDE and HCB were positively associated with rapid growth and with overweight. There was some indication that infant sex and exclusive breastfeeding duration may modify the effects of DDE, and that maternal prepregnancy BMI status may influence the effects of HCB. PCBs were not related to postnatal growth.

CONCLUSION

Prenatal exposure to DDE and HCB may be associated with early postnatal growth. Further research is needed to evaluate the persistence of these associations at older ages.

Prenatal exposure to hexachlorobenzene (HCB) and reproductive effects in a multicentre birth cohort in Spain

OBJECTIVE

To investigate the possible association between birth size or gestational length and maternal serum concentrations of hexachlorobenzene (HCB) in a population exposed to background levels.

METHODS

A total of 1568 mother-child pairs recruited in three Spanish areas (INMA Project) from 2004 to 2008 participated in the study. Multivariate analysis was performed between birth weight and length, weeks of gestation, preterm birth or small for gestational age and HCB concentrations in maternal serum.

RESULTS

The median concentration of HCB was 45.45 ng/g lipids. No association was found between HCB exposure levels and birth weight (β: -50.42 [-109.88; 9.04]), birth length (β: -0.07 [-0.32; 0.18]), gestation age (HR: 1.07 [0.94; 1.22]), small for gestational age (OR: 0.95 [0.56; 1.61]) and preterm birth (OR: 0.60 [0.29; 1.28]). Results remain similar after adjustment for other organochlorines.

CONCLUSION

Our findings support the idea that exposure to low levels of HCB does not affect the intrauterine growth nor the duration of gestation.

Relative effects of educational level and occupational social class on body concentrations of persistent organic pollutants in a representative sample of the general population of Catalonia, Spain

Scant evidence is available worldwide on the relative influence of occupational social class and educational level on body concentrations of persistent organic pollutants (POPs) in the general population. The objective was to analyse such influence in a representative sample of the general population of Catalonia, Spain. Participants in the Catalan Health Interview Survey aged 18-74 were interviewed face-to-face, gave blood, and underwent a physical exam. The role of age, body mass index (BMI), and parity was analysed with General Linear Models, and adjusted geometric means (GMs) were obtained. Crude (unadjusted) concentrations were higher in women and men with lower education, and in women, but not men, in the less affluent social class. After adjusting for age, in women there were no associations between POP levels and social class or education. After adjusting for age and BMI, men in the less affluent class had higher p,p'-DDE concentrations than men in class I (p-value=0.016), while men in class IV had lower HCB than men in the upper class (p-value<0.03). Also in contrast with some expectations, positive associations between education and POP levels were observed after adjusting for age and BMI in men; e.g., men with university studies had higher HCB concentrations than men with first stage of primary schooling (adjusted GM 153.9 and 80.5ng/g, respectively) (p-value<0.001). When education and social class were co-adjusted for, some positive associations with education in men remained statistically significant, whereas class remained associated only with p,p'-DDE. Educational level influenced blood concentrations of POPs more than occupational social class, especially in men. In women, POP concentrations were mainly explained by age/birth cohort, parity and BMI. In men, while concentrations were also mainly explained by age/birth cohort and BMI, both social class and education showed positive associations. Important characteristics of socioeconomic groups as age and BMI may largely explain crude differences among such groups in internal contamination by POPs. The absence of clear patterns of relationships between blood concentrations of POPs and indicators of socioeconomic position may fundamentally be due to the widespread, lifelong, and generally invisible contamination of human food webs. Decreasing historical trends would also partly explain crude socioeconomic differences apparently due to birth cohort effects.

Maternal diet, prenatal exposure to dioxins and other persistent organic pollutants and anogenital distance in children

We investigated the potential endocrine disruptive effect of prenatal exposure to persistent organic pollutants (POPs) through maternal diet, by measuring anogenital distance in newborns and young children. We included 231 mothers and their newborns measured at birth from the Rhea study in Crete, Greece and the Hmar study in Barcelona, Spain and 476 mothers and their children measured between 1 and 2 years from the Rhea study. We used food frequency questionnaires to assess maternal diet and estimated plasma dioxin-like activity by the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR-CALUX®) and other POPs in maternal samples. We defined a "high-fat diet" score, as a prenatal exposure estimate, that incorporated intakes of red meat, processed meat, fatty fish, seafood, eggs and high-fat dairy products during pregnancy. Increasing maternal "high-fat diet" score was related to increasing dioxin-like activity and serum concentrations of lipophilic persistent organic pollutants in maternal blood. An inverse dose-response association was found between "high-fat diet" score and anoscrotal distance in newborn males. The highest tertile of the maternal score was associated with -4.2 mm (95% CI -6.6 to -1.8) reduction in anoscrotal distance of newborn males, compared to the lowest tertile. A weak positive association was found between the "high-fat diet" score and anofourchetal distance in newborn females. In young children we found no association between maternal "high-fat diet" score and anogenital distances. In conclusion, maternal high-fat diet may be linked to high prenatal exposure to persistent organic pollutants and endocrine disruptive effects, resulting to phenotypic alterations of the reproductive system.

Human exposure to p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) in urban and semi-rural areas in southeast Spain: a gender perspective

p,p'-Dichlorodiphenyldichloroethylene (p,p'-DDE) is the main metabolite of pesticide dichlorodiphenyltrichloroethane and a marker of past exposure to this organochlorine pesticide. p,p'-DDE is considered a persistent organic pollutant with potential adverse effects on human health. The aims of the present study were to assess p,p'-DDE levels in serum and adipose tissue from a cohort of adults in southern Spain and to explore the predictors of exposure from a gender perspective. Chemical analyses were performed using gas chromatography-coupled mass spectrometry in tandem mode. The study population (n=387) was intraoperatively recruited in two areas of Granada Province (southern Spain), and data on potential predictors of these concentrations were gathered by questionnaire. The statistical analysis was performed by means of multivariable linear regression models. All participants showed detectable concentrations of p,p'-DDE in both serum and adipose tissue, with median concentrations of 175.7 and 93.0 ng/g lipid, respectively (p<0.001), and the two measurements showed positive correlations. Women showed higher concentrations than men (115.8 and 66.2 ng/g lipid, respectively, p<0.001). Concentrations in both matrices were positively associated with fatty food consumption, as well as with age and BMI, the latter only in adipose tissue. The multivariate model showed that, among women, adipose tissue concentrations were approximately 40% higher in those residing in the semi-rural area and 2-fold higher in those whose mothers had participated in agricultural activities during the pregnancy. In this study population, gender and place of residence play a key role in human exposure to p,p'-DDE and can be used to identify subjects at special risk of long-term exposure.

A biomonitoring study on blood levels of beta-hexachlorocyclohexane among people living close to an industrial area

BACKGROUND

A chemical plant manufacturing pesticides has been operating since the 1950's in the Sacco River Valley (Central Italy). In 2005, high beta-hexachlorocyclohexane (Beta-HCH) concentrations were found in milk of cows raised and fed near the river. We report the results of a biomonitoring study conducted in this region to evaluate the body burden of Beta-HCH and to identify the determinants of the human contamination.

METHODS

We defined four residential areas by their distance from the chemical plant and the river, and selected a stratified random sample of 626 people aged 25-64 years. We evaluated the association, in terms of the geometric mean ratio (GMR), between several potential determinants and Beta-HCH serum concentrations using multivariate linear regression analysis.

RESULTS

Two hundred forty-six serum samples were analysed to assess Beta-HCH levels (mean concentration: 99 ng/g lipid; Standard Deviation: 121; Geometric Mean: 60.6; Geometric Standard Deviation: 2.65). We found a strong association between Beta-HCH and living in the area close to the river (GMR: 2.00; 95%CI: 1.36-2.94). Beta-HCH levels were also associated with age, level of education, use of private wells and consumption of local food.

CONCLUSIONS

The results suggest that people living close to the river may have been contaminated by Beta-HCH, most likely through water from private wells and privately grown food. A programme of epidemiological and clinical surveillance is on-going on this population.

Associations between blood persistent organic pollutants and 25-hydroxyvitamin D3 in pregnancy

Persistent organic pollutants (POPs) are suggested to contribute to lower vitamin D levels; however, studies in humans are scarce and have never focused on pregnancy, a susceptibility period for vitamin D deficiency. We investigated whether serum levels of POPs were associated with circulating 25-hydroxyvitamin D3 [25(OH)D3] concentration in pregnancy. Cross-sectional associations of serum concentrations of eight POPs with plasma 25(OH)D3 concentration were analyzed in 2031 pregnant women participating in the Spanish population-based cohort INfancia y Medio Ambiente (INMA) Project. Serum concentrations of POPs were measured by gas chromatography and plasma 25(OH)D3 concentration was measured by high-performance liquid chromatography in pregnancy (mean 13.3±1.5weeks of gestation). Multivariable regression models were performed to assess the relationship between blood concentrations of POPs and 25(OH)D3. An inverse linear relationship was found between serum concentration of PCB180 and circulating 25(OH)D3. Multivariate linear regression models showed higher PCB180 levels to be associated with lower 25(OH)D3 concentration: quartile Q4 vs. quartile Q1, coefficient=-1.59, 95% CI -3.27, 0.08, p trend=0.060. A non-monotonic inverse relationship was found between the sum of predominant PCB congeners (PCB 180, 153 and 138) and 25(OH)D3 concentration: coefficient (95% CI) for quartile Q2 vs. Q1 [-0.50 (-1.94, 0.94)], quartile Q3 vs. Q1 [-1.56 (-3.11, -0.02)] and quartile Q4 vs. Q1 [-1.21 (-2.80, 0.38)], p trend=0.081. No significant associations were found between circulating 25(OH)D3 and serum levels of p,p'-DDE, p,p'-DDT, HCB, and ß-HCH. Our results suggest that the background exposure to PCBs may result in lower 25(OH)D3 concentration in pregnant women.

Evaluating the neurotoxic effects of lactational exposure to persistent organic pollutants (POPs) in Spanish children

Although the brain continues developing in the postnatal period, epidemiological studies on the effects of postnatal exposure to neurotoxic POPs through breast-feeding remain mostly inconclusive. Failure to detect associations between postnatal exposure and health outcomes may stem from the limitations of commonly employed approaches to assess lactational exposure. The aim of the present study was to assess whether lactational exposure to polychlorinated biphenyl-153 (PCB-153), dichlorodiphenyldichloroethylene (DDE), or hexachlorobenzene (HCB) as estimated with a physiologically based pharmacokinetic (PBPK) model, is associated with decrements in mental and psychomotor development scores of the Bayley Scales of Infant Development (BSID) test in children aged around 14-months of a subsample (N=1175) of the Spanish INMA birth cohort, and to compare this with the effects of prenatal exposure. Although in the present study population PCB-153, DDE and HCB exposure increased within the first months of postnatal life, no associations were found between different periods of postnatal exposure to these compounds and mental or psychomotor scores. Increasing prenatal PCB-153 concentrations were associated with worse mental and psychomotor scores, although significance was only reached for psychomotor development (β [95%CI]=-1.36 [-2.61, -0.11]). Indeed, the association between exposure and effects observed during prenatal life weakened gradually across periods of postnatal life. Results of the present study suggest that, although breastfeeding increases children's blood persistent organic pollutants (POPs) levels during postnatal life, deleterious effects of PCB-153 on neuropsychological development are mainly attributable to prenatal exposure.

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.

Prenatal exposure to polychlorinated biphenyls and child neuropsychological development in 4-year-olds: an analysis per congener and specific cognitive domain

Polychlorinated biphenyls (PCB) are synthetic organochlorine compounds with potential neurotoxic effects. Although negative effects on neuropsychological development have been observed in previous studies on PCB exposure, there are inconsistencies in these effects at current exposure levels of these compounds which are much lower than for previous generations. This study aimed to disentangle the effects of prenatal and postnatal PCB exposure on neuropsychological development at 4 years of age. This study is based on a population-based birth cohort design established in Menorca (Spain) as part of the INMA [Environment and Childhood] Project. We assessed general neuropsychological development using the McCarthy Scales of Children's Abilities (MCSA). A total of 422 4-year old children were assessed with the MCSA. Levels of PCBs were measured in cord blood (n=405) and in blood samples taken at 4 years (n=285). We found no statistically significant effects of the sum of prenatal PCBs on MCSA scores. Nevertheless, individual congener analyses yielded significant detrimental effects of prenatal PCB153 on the majority of MCSA scores, while no effects were reported for other congeners. The levels of PCBs at 4 years of age were not associated with neuropsychological development. Thus, prenatal exposure to low-level concentrations of PCBs, particularly PCB153, was associated with an overall deleterious effect on neuropsychological development at 4 years of age, including negative effects on executive function, verbal functions and visuospatial abilities, but not on motor development.

Factors influencing combined exposure to three indicator polychlorinated biphenyls in an adult cohort from Bolivia

Polychlorinated biphenyls are persistent organic pollutants that have been used for decades in several industrial applications. Although production of polychlorinated biphenyls was restricted from the 1970s in most countries, substantial amounts remain in old equipment and buildings and they have been detected in various environmental and biological matrices. The main objective of this study was to analyze predictors of the combined exposure to three non-dioxin-like polychlorinated biphenyls (congeners 138, 153 and 180) in serum and adipose tissue from an adult cohort (n=112) living in the city of Santa Cruz de la Sierra (Bolivia) and surrounding towns/villages. A second aim was to identify modifiers that might influence the statistical associations found, using crude, partially-adjusted, and global multiple linear regression models. Main predictors of serum concentrations were occupation and fatty food consumption, while those for adipose tissue concentrations included age, smoking habit, fatty food consumption, and residence. The differences between the two matrices might be derived from their biological meaning, given that adipose tissue concentrations are an indicator of chronic exposure to polychlorinated biphenyls while serum levels are a good predictor of ongoing exposure and the mobilization of polychlorinated biphenyls stored in fatty tissues. Body mass index was found to be an important modifier of these associations.

Concentrations of organochlorine pesticides and polychlorinated biphenyls in human serum and adipose tissue from Bolivia

Organochlorine pesticides and polychlorinated biphenyls (PCBs) are synthetic chemicals that are highly resistant to biodegradation and have proven adverse health effects. The objectives of this study were to determine concentrations of three selected organochlorine pesticides (p,p'-DDT, p,p'-DDE, HCB) and three specific PCB congeners (PCB 138, 153, 180) in adipose tissue and serum samples from an urban adult population (n=112) in the city of Santa Cruz de la Sierra, Bolivia, and to investigate their relationships within and between the two matrices and with selected socio-demographic characteristics. The percentages of samples positive for these compounds ranged from 40% for PCB 180 to 100% for p,p'-DDE in adipose tissue, and from 21% for HCB to 93% for p,p'-DDE in serum. Median number of residues per sample was five for adipose tissue and three for serum. Geometric mean concentrations indicate a considerable historical and recent exposure to organochlorine pesticides and PCBs in this population. Adipose tissue:serum ratios ranged from 149.3 to 590.3 (wet basis) and from 0.9 to 3.5 (lipid basis). We found positive and statistically significant correlations between adipose tissue and serum concentrations only in p,p'-DDE and HCB. This novel study in Bolivia underlines the need for human biomonitoring to assess exposure to environmental pollutants in South America.

Contribution of sociodemographic characteristics, occupation, diet and lifestyle to DDT and DDE concentrations in serum and adipose tissue from a Bolivian cohort

The organochlorine pesticide p,p'-Dichlorodiphenyltrichloroethane (DDT) was widely used in the early 1960s-70s for vector control in tropical and subtropical areas of South America. Due to its persistence, DDT has a high potential to bioaccumulate in the food chain and living organisms and is a major public health concern, especially in South America. The main purpose of the present study was to investigate predictors of serum and adipose tissue concentrations of p,p'-DDT and its main metabolite, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), in an adult cohort (n=112) from Santa Cruz de la Sierra, Bolivia, using multiple linear regression models. These models explained 29.3-47.8% of the variability in adipose tissue concentrations of p,p'-DDT and p,p'-DDE, respectively, and 32.9-47.0% of that in serum. Main exposure predictors included age, occupational class, residence, diet, smoking habit, and accumulated breastfeeding time. This is one of the few studies to explore predictors of human exposure to these chemicals using a multivariate approach in a South American population. Results show that predictors of human exposure to p,p'-DDT and p,p'-DDE in Santa Cruz de la Sierra may diverge from those found in other populations of the world, due to particular sociodemographic and lifestyle characteristics of this region.

Empirical analyses of the influence of diet on human concentrations of persistent organic pollutants: a systematic review of all studies conducted in Spain

BACKGROUND

Numerous studies analyzed concentrations of persistent organic pollutants (POPs) in human samples, and in many types of foods; however, food consumption is less commonly included in studies on the determinants of POP concentrations in humans, and these approaches are rarely integrated with surveys of food intake to estimate the amount and safety of human POP intake from food.

OBJECTIVE

To analyze the main characteristics and findings of all studies conducted in Spain that quantitatively assessed the influence of diet on human concentrations of POPs.

METHODS

Studies published until December 2010 (with no other time restrictions) were identified through Medline/PubMed, ISI-Thomson, ScienceDirect, and SciELO databases.

RESULTS

We identified 25 papers, from 19 different studies. Twelve papers were published in 2009-2010. All studies but one were based on subgroups not representative of the general population, and over half were limited to women. Serum was the most used biological matrix, while p,p'-DDE, HCB and PCBs were the most frequently analyzed compounds. Food intakes were measured with heterogeneous food frequency questionnaires. The most consistent association was between fish consumption and PCBs and HCB, followed by dairy products and PCBs. A few studies observed a relationship between meat and some POPs, whilst intake of vegetables, fruits and cereals was rarely related to POP levels. Only 3 studies did not find any relationship between dietary habits and POP concentrations.

CONCLUSIONS

In spite of methodological heterogeneity, the studies were able to quantify to what extent consumption of foods from animal origin (fish, milk, dairy products and meat) is related to higher body concentrations of POPs. As in a few other countries, in Spain food consumption is increasingly analyzed as a major determinant of human POP intake.