A novel biomarker for anti-androgenic activity in placenta reveals risks of urogenital malformations.

It has been hypothesized that the rise in male reproductive disorders over recent decades may at least be partially attributable to environmental factors, including chemical exposures, but observed associations with single chemicals were rather weak. The aim of this case-control study was to explore the relationship between exposure to mixtures of (anti-)androgenic chemicals during pregnancy and the risk of cryptorchidism and/or hypospadias in offspring, using the total effective xenobiotic burden of anti-androgens (TEXB-AA) as a biomarker. A subsample of 29 cases (16 of cryptorchidism, 12 of hypospadias, and one of both disorders) and 60 healthy controls was nested in a cohort of male newborns recruited between October 2000 and July 2002. The (anti-)androgenic activity of placenta samples collected at delivery was assessed using TEXB-AA biomarker, combined with a bioassay-directed fractionation protocol that separated endogenous hormones from most (anti-)androgenic chemicals by normal-phase HPLC. The bioassay measures the androgen-induced luciferase activity and the inhibition of this pathway by (anti-)androgens. First, we collected 27 HPLC fractions in each placenta extract, which were all tested in the bioassay. The multivariable statistical analyses indicated a statistically significant positive dose-response association between the potent anti-androgenic activity of the HPLC fraction collected during minutes 1-2 (F2) and the risk of malformations (odds ratio: 2.33, 95% CI: 1.04-5.23). This study represents a novel approach for the estimation of combined effects of the total anti-androgenic load and the associations suggest an effect of environmental pollutants on the development of fetal reproductive tract.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/149/6/605/suppl/DC1.

Adipose tissue concentrations of persistent organic pollutants and prevalence of type 2 diabetes in adults from Southern Spain.

There is increasing evidence that environmental factors play an important role in the development of type 2 diabetes. Several persistent organic pollutants are suspected to contribute to the increasing prevalence and risk of type 2 diabetes. The aim of this study was to investigate the association of the body burden of three organochlorine pesticides and three polychlorinated biphenyls and the overall estrogenic activity with the risk of type 2 diabetes in a sample of adults from Southern Spain. Samples of adipose tissue and serum were obtained from 386 subjects undergoing non-cancer-related surgery and were extracted using validated methodologies. Residues of persistent organic pollutants were analyzed by means of high-resolution gas chromatography with a mass spectrometry detector in tandem mode. The overall estrogenicity of the adipose tissue extracts was measured by using the total effective xenoestrogen burden (TEXB) biomarker. Data on lifestyle, dietary habits, and health status were gathered from face-to-face interviews and clinical records. Statistical analyses were performed with unconditional logistic regression and different adjustment levels. In the models adjusted for adipose tissue origin, sex, age, and body mass index, the 2nd and 3rd tertiles of adipose tissue concentrations of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) were positively associated with the risk of diabetes [odds ratios (95% confidence interval)=3.6 (0.8-17.3) and 4.4 (1.0-21.0), respectively]. A positive association with ß-hexachlorocyclohexane was also found when body mass index and adipose tissue origin were removed from the models, with odds ratios (95% confidence interval) of 3.3 (1.0-10.4) and 5.5 (1.7-17.3), for the 2nd and 3rd tertiles of exposure, respectively. In addition, a statistically significant interaction was observed between p,p'-DDE and body mass index, such that the risk of diabetes increased with tertiles of exposure in a linear manner in non-obese subjects but not in the obese, in whom an inverted U-shape pattern was observed.

Bisphenol A and cognitive function in school-age boys: Is BPA predominantly related to behavior?

BACKGROUND: Bisphenol A (BPA) has been associated with impairments in children's behavior, but few studies have investigated its relationship with cognitive function. OBJECTIVE: To investigate the association of urinary BPA concentrations with cognitive domains and intelligence quotient (IQ) in Spanish boys. METHODS: BPA levels were quantified by liquid chromatography-tandem mass spectrometry (LC-MS-MS) in one spot urine sample from 269 boys of the INMA-Granada cohort, in their follow-up at 9-11 years of age. Cognitive function was evaluated by a trained psychologist using a comprehensive neuropsychological test battery (including general intelligence, language skills, working memory, attention, impulsivity, visual-motor coordination, processing speed and executive function, among others). Cross-sectional associations between BPA levels and neuropsychological standardized scores were analyzed by adjusted linear and logistic regression models. RESULTS: Median (P25, P75) BPA concentrations were 4.76 (2.77, 9.03) µg/L and 4.75 (2.75, 10.2) µg/g of creatinine (Cr). Boys in the third and fourth quartile of volume-based BPA concentrations showed better processing speed scores than boys in the first quartile (ß = 5.47; 95%CI: 1.4, 9.4 and ß = 3.57; 95%CI: -0.4, 7.5, respectively); and boys in the third quartile showed better inhibitory control (ß = 1.6; 95%CI: -0.3, 3.5) and impulsivity (ß= -4.2; 95%CI: -9.0, 0.0). In contrast, boys in the fourth quartile showed poorer working memory scores than those in the first quartile (ß= -1.0; 95%CI: -2.1, -0.1). All these associations were attenuated when Cr-standardized BPA concentrations were considered. Cr-based BPA concentrations were also associated with a higher risk of being below the 20th percentile of working memory scores [ORa = 1.51; 95%CI: 1.01, 2.25]. DISCUSSION: Our findings do not support an association between urinary BPA concentrations and cognitive function or IQ among boys, except for working memory. BPA was previously found to be associated with behavior problems in the same study population, suggesting that BPA may predominantly affect the behavior of children rather than their cognitive function, in line with previous epidemiologic studies.

Presence of Bisphenol A and Parabens in a Neonatal Intensive Care Unit: An Exploratory Study of Potential Sources of Exposure.

BACKGROUND: Newborns in neonatal intensive care units (NICUs) are in contact with a variety of medical products whose production might include synthetic chemicals with hormonal activity. OBJECTIVES: Our aim was to assess the content of bisphenol A (BPA) and parabens (PBs) and the hormone-like activities of a subset of medical products commonly used in NICUs in prolonged intimate contact with NICU newborns. METHODS: Fifty-two NICU items were analyzed, determining the concentrations of BPA and PBs [methyl- (MeP), ethyl- (EtP), propyl- (PrP), and butylparaben (BuP)] and using the E-Screen and PALM-luciferase assays to measure the in vitro (anti-)estrogenic and (anti-)androgenic activity, respectively, of the extracts. Items found to have elevated BPA/PB content or hormone-like activities were further extracted using leaching methodologies. RESULTS: BPA was found in three-fifths and PBs in four-fifths of tested NICU items, and ∼25% and ∼10% of extracts evidenced estrogenic and anti-androgenic activity, respectively. The highest BPA content was found in the three-way stopcock (>7.000 ng/g), followed by patterned transparent film dressing, gastro-duodenal feeding tubes, sterile gloves, single-lumen umbilical catheters, and intravenous (IV) infusion extension sets (concentrations ranged from 100 to 700 ng/g BPA). A total PB concentration (∑PBs) >100 ng/g was observed in several items, including light therapy protection glasses, patterned transparent film dressing, winged IV catheters, IV infusion extension sets, and textile tape. The highest estrogenic activity [>450 pM estradiol equivalent (E2eq)] was found in small dummy nipples, three-way stopcocks, and patterned transparent film dressing and the highest anti-androgenic activity [>5 mM procymidone equivalent units per gram (Proceq/g)] in small dummy nipples and three-way stopcocks. DISCUSSION: According to these findings, neonates might be exposed to multiple sources of BPA and PBs in NICUs via inhalation, dermal, oral, and IV/parenteral routes. There is a need to address the future health implications for these extremely vulnerable patients and to adopt precautionary preventive measures as a matter of urgency. https://doi.org/10.1289/EHP5564.

Biomonitoring of environmental estrogens in human tissues.

Two examples are presented for the application of the total effective xenoestrogen burden as biomarker of chemical exposure measured in tissue samples from patients recruited for two case-control studies. The first study focused on environmental chemicals with hormone mimicking activity, the so-called environmental estrogens, and their participation in the etiology of breast cancer. The second study investigated mother-child exposure to persistent organochlorine chemicals and assessed their combined effect on the risk of male urogenital malformations in the newborn.

Relationship between occupational social class and exposure to organochlorine pesticides during pregnancy.

BACKGROUND: Little evidence is available on the influence of socioeconomic factors on exposure to persistent organic pollutants, especially during vulnerable periods such as pregnancy and early life. OBJECTIVE: To investigate the relationship of maternal social class with placental concentrations of organochlorine pesticides (OCPs) and their combined estrogenic activity measured with a biomarker of exposure. METHODS: Exposure to 16 OCPs (DDTs, endosulfans, and seven other compounds) and the total effective xenoestrogenic burden (TEXB) were analyzed in placentas from a mother-child cohort. OCP concentrations were quantified by gas chromatography and mass spectrometry, and TEXB was assessed with the E-Screen bioassay. Social class was classified according to maternal occupation. Multivariate regression analysis was conducted to examine variations in pesticide exposure and TEXB as a function of maternal social class in 257 subjects. RESULTS: Placental p,p'-DDT concentrations were higher in social classes III and IV than in classes I-II (the most affluent); concentrations of the sum of DDTs were higher in class IV; and exposure to the sum of endosulfans was greater in class III. HCB concentrations were higher among women in class IV than in classes I-II and among manual (classes III-V) than non-manual workers. However, the trend across social classes was only statistically significant for HCB. Social class significantly explained 10% of the variability in concentrations of the sum of endosulfans. CONCLUSION: There is a need to explore whether more disadvantaged populations suffer higher levels of exposure to pesticides or other environmental chemicals and how different social processes contribute to this exposure.

Assessment of total effective xenoestrogen burden in adipose tissue and identification of chemicals responsible for the combined estrogenic effect.

Test systems to screen for estrogenicity and appropriate biomarkers of human exposure are required for epidemiological studies of endocrine disruption. We addressed these issues by developing and standardising a method to assess the total estrogenic xenobiotic burden in human adipose tissue. In this study, which is the continuation of a previous work, we have improved the protocol for extensive fractionation of a higher number of tissue samples in order to investigate bioaccumulated xenoestrogens that are candidates for estrogenicity and to assess their combined estrogenic effect. This was achieved by extensive HPLC separation of xenoestrogens from endogenous hormones followed by testing of individual fractions in the E-Screen test for estrogenicity. Organochlorine pesticides, PCBs and halogenated bisphenols and alkylphenols were collected in the most lipophilic fractions, followed by progestins, androgens and estradiol esters, and then by steroidal estrogens; phyto- and myco-estrogens were collected around the end of the run. These results were confirmed by exhaustive chemical analysis. In 458 human adipose tissue samples, the total effective xenoestrogen burden was positive in 75% of samples in the pooled fraction that contained organohalogenated xenoestrogens (mean 515.3 pM Eeq/g lipid; range 0-14.5 nM) and in 82% of samples in the pooled fraction where natural estrogens eluted (mean 696.6 pM Eeq/g lipid; range 0-12.9 nM). Organochlorine pesticides emerged as candidate chemicals for the estrogenicity of the first pooled fraction, because DDT and derivatives were present in 98.3% of the samples. However, no correlation was found between the concentration of any single chemical and the estrogenicity determined in the bioassay. There may be several reasons for this lack of concordance: (i) the estrogenic effects depicted in the E-Screen bioassay are a consequence of the combined effect of several organohalogens or (ii) the proliferative effect is due to other chemicals not measured. Because additive, synergistic or antagonistic mechanisms may account for the final effect observed in the pooled fractions, the approach proposed in this work is more appropriate for exposure assessment in epidemiological studies than the determination of individual chemicals in human samples.