p,p′-DDT andp,p′-DDE effects on egg production,eggshell thickness,and reproduction of japanese quail

Summary p,p-DDT and p,p-DDE were investigated for effects on egg production and eggshell thickness in Japanese quail. p,p-DDT was examined for effects on hatchability and fertility. DDE was tested at 0, 2, 10, 40, and 200 ppm in the diet. No evidence suggested that DDE affected number of eggs laid, egg weight, or eggshell thickness at any level of DDE tested. DDT was tested at 1, 2.5, 10, and 40 ppm in the diet. In one experiment, quail fed DDT at 40 ppm and caged in male-female pairs broke more eggs than quail caged similarly but fed lower amounts of DDT or than quail fed an equal amount of DDT but caged alone. DDT did not detectably reduce eggshell thickness, number of eggs laid, fertility, or hatchability. However, paired quail laid fewer eggs than did single quail in two experiments and laid eggs with thinner shells in one experiment.     

Levels of β-HCH,HCB, p,p′-DDE,p,p′-DDT and PCBs in human milk from a continental town in Croatia,Yugoslavia

Summary Concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs were determined by gas chromatography in 50 human milk samples collected from the general population during 1981/1982 in a continental town in Croatia (Yugoslavia). The samples were collected between one and 22 weeks after delivery from mothers breast-feeding one child only. The mothers' age was 18 to 31 years, and they were nursing their first or second child. All 50 samples contained -HCH, HCB, p,p-DDE and PCBs, whereas p,p-DDT was present in 37 samples. The concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs expressed on a whole milk basis were (median in g/kg): 11, 7.1, 67, 7.3 and 22 respectively, and expressed on a fat basis (median in mg/kg): 0.28, 0.21, 1.9, 0.18 and 0.62 respectively. The fat content was 3.7% (median). PCBs were present in a mixture containing penta-, hexa- and heptachlorobiphenyls.     

Endocrine-Disrupting Effects of Nonylphenol, Bisphenol A, and p,p′-DDE on Rana nigromaculata Tadpoles

No abstract available.     

Residues of p,p′-DDE and mercury in lake trout as a function of age

Lake trout (Salvelinus namaycush) of known age from 1 to 12 years were taken from Cayuga Lake in central New York State in 1991 and p,p-DDE and mercury were determined in their flesh. The concentrations of p,p-DDE and mercury increased significantly (p<0.001) with increasing age of the fish. The concentration of p,p-DDE also increased significantly (p<0.001) with increasing fat content. The concentrations of p,p-DDE were much lower than those found in Cayuga Lake trout of similar age captured in 1978.     

Effects of Incubation Time and Organism Density on the Bioaccumulation of Soil-Borne p,p′-DDE by the Earthworm, Eisenia fetida

The effect of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), an organochlorine pesticide, was evaluated on phagocytic (phagocytic index and percentage of active cells) and hematological parameters in Nile tilapia. Experimental data showed that an acute exposure to endosulfan (4.0 and 7.0 μg/L) induces a significant decrease in the phagocytic index and the percentage of active cells in peripherical blood of Nile tilapia. However, hemoglobin concentration (Hb), hematocrit (Hto), red blood cell count (RBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were not significantly altered in fish exposed to endosulfan compared with control group.     

Disposition of β-hexachlorocyclohexane,p,p′-DDT,and trans-chlordane administered subcutaneously to monkeys (Macaca fascicularis)

To evaluate skin lipid analysis for the accumulation level of environmental pollutants, the correlations between organochlorine pesticide residues in adipose tissue, blood, and skin lipids of monkeys were studied. The mixture of -hexachlorocyclohexane (-HCH), p,p-DDT, and trans-chlordane was subcutaneously given to monkeys once weekly for 5 weeks at dose levels of 1 and 10 mg/kg. The chemicals distributed in adipose tissue, blood, and skin lipids were determined six times after the last dosing at intervals of 4 to 9 weeks.Oxychlordane and p,p-DDE were detected in all tissues together with the administered chemicals. In blood and adipose tissue, trans-chlordane decreased rapidly and oxychlordane and p,p-DDE increased gradually and then remained at constant levels. -HCH and p,p-DDT in adipose tissue increased until the 12th week and then decreased in all animals. The correlation coefficients between blood and adipose tissue regardless of dose level and collection time for each chemical ranged from 0.83 to 0.94. Correlation coefficients between skin lipids and adipose tissue varied with the chemical, namely, 0.31, 0.72, 0.81, 0.81, and 0.83 for p,p-DDE, tras-chlordane, p,p-DDT, -HCH, and oxychlordane, respectively. The results indicated that skin lipid analysis may be useful for the evaluation of specific pollutants in the body burden.     

一步提取、净化法测定鱼组织中的p,p’-DDT、p,p-DDD、p,p’-DDE

通常,测定组织样品中氯代农药的方法包括溶剂提取、脂肪分离、提取物的净化、气相色谱分析等步骤,十分费时耗力,不适于分析大批环境样品。本文作者提出了一个新方法,将提取、分离、净化容于一简单步骤之中,回收率高、方法简单。     

Polychlorobiphenyl congeners,p,p′-DDE,and sperm function in humans

170 seminal samples from fertile men, men with idiopathic oligospermia or azoospermia and men status post vasectomy were analyzed for 74 polychlorobiphenyl (PCB) congeners,p,p-DDE, mirex, and hexachlorobenzene using the technique of glass capillary gas chromatography with electron capture detection. Low concentrations of 32 PCB congeners were measured (mean total PCB residue of 5.8 ng/g wet weight). The application of multiple linear regression analysis to the data is described and the result is critically evaluated. There is a correlation between sperm motility and count. There are indications that the concentrations of three PCB congeners (2,4,5,245- and 2,4,5,234-hexachlorobiphenyl and 2,4,5,34-pentachlorobiphenyl) are inversely correlated with sperm motility index in samples with a sperm count less than 20 million cells/ml. The implications of the discerned associations are discussed.     

Influence of Glutathione S-Transferase Polymorphisms on Cognitive Functioning Effects Induced by p,p′-DDT among Preschoolers

Background

Early-life exposure to p,p′-DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] is associated with a decrease in cognitive skills among preschoolers at 4 years of age. We hypothesized that genetic variability in glutathione S-transferase (GST) genes (GSTP1, GSTM1, and GSTT1) could influence the effects of prenatal exposure to p,p′-DDT.

Methods

We used data from 326 children assessed in a prospective population-based birth cohort at the age of 4 years. In that study, the McCarthy Scales of Children’s Abilities were administrated by psychologists, organochlorine compounds were measured in cord serum, and genotyping was conducted for the coding variant Ile105Val from GSTP1 and for null alleles from GSTM1 and GSTT1. We used linear regression models to measure the association between organochlorines and neurodevelopmental scores by GST polymorphisms.

Results

p,p′-DDT cord serum concentration was inversely associated with general cognitive, memory, quantitative, and verbal skills, as well as executive function and working memory, in children who had any GSTP1 Val-105 allele. GSTP1 polymorphisms and prenatal p,p′-DDT exposure showed a statistically significant interaction for general cognitive skills (p = 0.05), quantitative skills (p = 0.02), executive function (p = 0.01), and working memory (p = 0.02). There were no significant associations between p,p′-DDT and cognitive functioning at 4 years of age according to GSTM1 and GSTT1 polymorphisms.

Conclusions

Results indicate that children with GSTP1 Val-105 allele were at higher risk of the adverse cognitive functioning effects of prenatal p,p′-DDT exposure.     

Genistein‐induced upregulation of p21 WAF1 , downregulation of cyclin B,and induction of apoptosis in prostate cancer cells

Increased soy consumption in Asian diets, resulting in increased serum isoflavone levels, has been associated with a decreased risk for prostate adenocarcinoma (PCa). The isoflavone genistein is believed to be the anticancer agent found in soy, and significant levels of genistein have been detected in human prostatic fluid, implicating the role of genistein in PCa prevention. Recent studies have demonstrated genistein's ability to inhibit cell growth and induce apoptosis in several cell lines; however, the molecular mechanisms of genistein's effect are not known. We have evaluated the mechanism by which genistein may inhibit PCa cell growth. Here we report that genistein inhibits PCa cell growth in culture in a dose‐dependent manner, which is accompanied by a G₂/M cell cycle arrest. Cell growth inhibition was observed with concomitant downregulation of cyclin B, upregulation of the p21^WAF1 growth‐inhibitory protein, and induction of apoptosis. Collectively, these results provide experimental evidence for a novel effect of genistein on cell cycle gene regulation, resulting in the inhibition of cell growth and ultimate demise of tumor cells.     

Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,p’-DDE) with Testosterone Levels in Adolescent Males

Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized.Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures.Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders.Results: The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: –10.8, –0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: –11, –0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: –7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: –0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels.Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The positive relationship between p,p´-DDE and testosterone indicates that not all POPs act similarly.Citation: Schell LM, Gallo MV, Deane GD, Nelder KR, DeCaprio AP, Jacobs A; Akwesasne Task Force on the Environment. 2014. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p´-DDE) with testosterone levels in adolescent males. Environ Health Perspect 122:304–309; http://dx.doi.org/10.1289/ehp.1205984     

In Vitro Effects of the Endocrine Disruptor p,p’-DDT on Human Follitropin Receptor

Background:

1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene (p,p′-DDT) is a persistent environmental endocrine disruptor (ED). Several studies have shown an association between p,p′-DDT exposure and reproductive abnormalities.

Objectives:

To investigate the putative effects of p,p′-DDT on the human follitropin receptor (FSHR) function.

Methods

and Results: We used Chinese hamster ovary (CHO) cells stably expressing human FSHR to investigate the impact of p,p′-DDT on FSHR activity and its interaction with the receptor. At a concentration of 5 μM p,p′-DDT increased the maximum response of the FSHR to follitropin by 32 ± 7.45%. However, 5 μM p,p′-DDT decreased the basal activity and did not influence the maximal response of the closely related LH/hCG receptor to human chorionic gonadotropin (hCG). The potentiating effect of p,p′-DDT was specific for the FSHR. Moreover, in cells that did not express FSHR, p,p′-DDT had no effect on cAMP response. Thus, the potentiating effect of p,p′-DDT was dependent on the FSHR. In addition, p,p′-DDT increased the sensitivity of FSHR to hCG and to a low molecular weight agonist of the FSHR, 3-((5methyl)-2-(4-benzyloxy-phenyl)-5-{[2-[3-ethoxy-4-methoxy-phenyl)-ethylcarbamoyl]-methyl}-4-oxo-thiazolidin-3-yl)-benzamide (16a). Basal activity in response to p,p′-DDT and potentiation of the FSHR response to FSH by p,p′-DDT varied among FSHR mutants with altered transmembrane domains (TMDs), consistent with an effect of p,p′-DDT via TMD binding. This finding was corroborated by the results of simultaneously docking p,p′-DDT and 16a into the FSHR transmembrane bundle.

Conclusion:

p,p′-DDT acted as a positive allosteric modulator of the FSHR in our experimental model. These findings suggest that G protein–coupled receptors are additional targets of endocrine disruptors.

Citation:

Munier M, Grouleff J, Gourdin L, Fauchard M, Chantreau V, Henrion D, Coutant R, Schiøtt B, Chabbert M, Rodien P. 2016. In vitro effects of the endocrine disruptor p,p′-DDT on human follitropin receptor. Environ Health Perspect 124:991–999; http://dx.doi.org/10.1289/ehp.1510006     

Interference of Xenoestrogen o,p′-DDT on the Action of Endogenous Estrogens at Environmentally Realistic Concentrations

Estrogenic effects of individual chemicals and mixtures of 17β-estradiol (E₂) and o,p′-DDT were examined using pS2 and PR gene expressions in MCF-7 cells. Interactions between E₂ and o,p′-DDT were evaluated by a statistical method based on factorial design. At levels close to environmentally realistic concentrations, no significant interactions between E₂ and o,p′-DDT were observed, suggesting that the xenoestrogen (o,p′-DDT) could act in an additive way with the endogenous estrogen (E₂). These results demonstrated the utility of this statistical method in a mixture study, and highlight the potential interference and health risk of low-level xenoestrogens, such as o,p′-DDT.     

DDT Exposure of Zebrafish Embryos Enhances Seizure Susceptibility: Relationship to Fetal p,p′-DDE Burden and Domoic Acid Exposure of California Sea Lions

Background

California sea lions have a large body burden of organochlorine pesticides, and over the last decade they have also been subject to domoic acid poisoning. Domoic acid poisoning, previously recognized in adult animals, is now viewed as a major cause of prenatal mortality. The appearance of a chronic juvenile domoic acid disease in the sea lions, characterized by behavioral abnormalities and epilepsy, is consistent with early life poisoning and may be potentiated by organochlorine burden.

Objective

We investigated the interactive effect of DDT (dichlorodiphenyltrichloroethane) on neurodevelopment using a zebrafish (Danio rerio) model for seizure behavior to examine the susceptibility to domoic acid–induced seizures after completion of neurodevelopment.

Methods

Embryos were exposed (6–30 hr postfertilization) to either o,p′-DDT or p,p′-DDE (dichlorodiphenyldichloroethylene) during neurodevelopment via a 0.1% dimethyl sulfoxide solution. These larval (7 days postfertilization) fish were then exposed to either the seizure-inducing drug pentylenetetrazol (PTZ) or domoic acid; resulting seizure behavior was monitored and analyzed for changes using cameras and behavioral tracking software.

Results

Embryonic exposure to DDTs enhanced PTZ seizures and caused distinct and increased seizure behaviors to domoic acid, most notably a type of head-shaking behavior.

Conclusion

These studies demonstrate that embryonic exposure to DDTs leads to asymptomatic animals at completion of neurodevelopment with greater sensitivity to domoic acid–induced seizures. The body burden levels of p,p′-DDE are close to the range recently found in fetal California sea lions and suggest a potential interactive effect of p,p′-DDE embryonic poisoning and domoic acid toxicity.     

Polychlorinated biphenyl congeners (PCBs),p,p′-DDE and hexachlorobenzene in human milk in three areas of upstate New York

Forty human milk samples from women in an urban and a rural vicinity on Lake Ontario (Rochester and Oswego) and a mixed urban and rural location on the Hudson River (Albany), New York, were analyzed for 74 PCB congeners,p,p-DDE, hexachlorobenzene, and mirex in order to determine the intake of breast-fed infants. All of the compounds were detected in the samples, but only eight PCB congeners andp,p-DDE accounted for 88% of the chlorinated hydrocarbons detected.p,p-DDE was the predominant pollutant (mean 78 ng/g wet weight), but the levels detected were low compared with the results from other parts of North America. Eight individual PCB congeners comprise 52% of the total PCB residue (mean 26.5 ng/g of whole milk); they ranged in mean concentration from 3.2 ng/g (2,4,5,2,4,5-hexachlorobiphenyl) to 1 ng/g (2,3,4,3,4-pentachlorobiphenyl). Statistical correlation analysis among PCB congeners indicates a possible higher exposure to less chlorinated congeners at Oswego than at Albany.     

孕产妇血清中p,p’-DDE暴露水平及其影响因素

目的研究孕产妇血清中p,p’-DDE暴露水平并对其影响因素进行分析。方法于2010年选择某市一所医院妇产科的300名孕产妇作为研究对象,测定孕产妇静脉血清中p,p’-DDE的含量,并对相关影响因素开展问卷调查。结果p,p’-DDE在孕产妇血清中的检出率为89.47%(221/247),Speaman分析表明孕产妇BMI和年龄与其静脉血清中p,p’-DDE的含量呈正相关,且差异有统计学意义(P<0.05);多因素分析结果提示:孕产妇的年龄每增加1岁和体质指数(BMI)每增加1 kg/m2,孕妇血清中p,p’-DDE的含量分别相应增加29.01 ng/g(以脂计)和23.73 ng/g(以脂计),有妊娠史的孕产妇比无妊娠史的孕产妇静脉血中p,p’-DDE的含量低161.64 ng/g(以脂计)。结论孕产妇年龄的增加及BMI的增高可能会导致静脉血清中p,p’-DDE暴露水平的升高;有妊娠史的孕产妇血清中的p,p’-DDE含量可能较无妊娠史的孕产妇低。     

Promoter Methylation of E-Cadherin,p16, and RAR-β2 Genes in Breast Tumors and Dietary Intake of Nutrients Important in One-Carbon Metabolism

Aberrant DNA methylation plays a critical role in carcinogenesis, and the availability of dietary factors involved in 1-carbon metabolism may contribute to aberrant DNA methylation. We investigated the association of intake of folate, vitamins B₂, B₆, B₁₂, and methionine with promoter methylation of E-cadherin, p16, and RAR-β₂ genes in archived tumor tissues from incident, primary breast cancer cases in a population-based case-control study. Real-time methylation-specific PCR was performed on 803 paraffin-embedded samples; usual dietary intake was queried from a food frequency questionnaire. Unconditional logistic regression was used to derive adjusted odds ratios and 95% confidence intervals for likelihood of promoter methylation for high compared to low intake of those 1-carbon nutrients. Overall, in case-case comparisons, dietary intakes of folate, vitamins B₂, B₆, B₁₂, and methionine were not associated with likelihood of promoter methylation of E- cadherin, p16, and RAR-β₂ for all cases combined or within strata defined by menopausal status and estrogen receptor status in this study. This finding, however, does not exclude the possibility that intake of such nutrients might have the ability to modulate promoter methylation in normal or premalignant (dysplastic) breast tissue.     

Factors associated with plasma concentrations of polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (p,p’-DDE) in the Canadian population

This study describes blood plasma concentrations of PCBs and p,p’-DDE in the Canadian population aged 20–79 years. PCBs and p,p’-DDE were measured in 1668 participants in the Canadian Health Measures Survey, Cycle 1 (2007–2009). We investigated how concentrations vary by sociodemographic, anthropometric, and lifestyle variables, identified factors associated with exposures, and evaluated concentrations against health-based guidance values. Congeners of PCB most commonly detected were PCB-138, PCB-153, and PCB-180. p,p’-DDE was detectable in > 99% of the samples. Factors associated with ∑PCBs were age, region of birth, frequency of fish consumption, and liver intake (R² = 58.1%). For p,p’-DDE, significant factors were sex, age, region of birth, household education, and ethnic origin (R² = 47.0%). PCB concentrations in Canadians were similar to those in the United States, and lower than those reported in Europe. A small percentage equalled or exceeded the Human Biomonitoring value of 3.5 µg/L for PCBs. Few exceedances of the p,p’-DDE biomonitoring equivalent were observed.