Dichlorodiphenyldichloroethylene Exposure Research Articles

Incubation Temperature and Maternal Resource Provisioning, but Not Contaminant Exposure, Shape Hatchling Phenotypes in a Species with Temperature-Dependent Sex Determination.

AbstractThe environment experienced during embryonic development is a rich source of phenotypic variation, as environmental signals have the potential to both inform adaptive plastic responses and disrupt normal developmental programs. Environment-by-embryo interactions are particularly consequential for species with temperature-dependent sex determination, a mode of sex determination common in non-avian reptiles and fish, in which thermal cues during a discrete period of development drive the formation of either an ovary or a testis. Here we examine the impact of thermal variation during incubation in combination with developmental exposure to a common endocrine-disrupting contaminant on fitness-related hatchling traits in the American alligator (Alligator mississippiensis), a species with temperature-dependent sex determination. Using a factorial design, we exposed field-collected eggs to five thermal profiles (three constant temperatures, two fluctuating temperatures) and two environmentally relevant doses of the pesticide metabolite dichlorodiphenyldichloroethylene; and we quantified incubation duration, sex ratios, hatchling morphometric traits, and growth (9-10 days post-hatch). Whereas dichlorodiphenyldichloroethylene exposure did not generally affect hatchling traits, constant and fluctuating temperatures produced diverse phenotypic effects. Thermal fluctuations led to subtle changes in incubation duration and produced shorter hatchlings with smaller heads when compared to the constant temperature control. Warmer, male-promoting incubation temperatures resulted in larger hatchlings with more residual yolk reserves when compared to cooler, female-promoting temperatures. Together, these findings advance our understanding of how complex environmental factors interact with developing organisms to generate phenotypic variation and raise questions regarding the mechanisms connecting variable thermal conditions to responses in hatchling traits and their evolutionary implications for temperature-dependent sex determination.

Varied parameters and utility of the anal position index: a systematic review and meta-analysis.

The anal position index (API) was described in 1984 by Reisner et al. Since then, it has been measured in different ethnic populations and its utility in various medical conditions have been explored. We aimed to review the literature regarding the various values reported analytically. A Pubmed Search was carried out with the terms Anal Position Index. There were 158 articles hit by the search. The description of the API was uniform in all studies, described as ratio of anus-fourchette distance in girls and anus-scrotum distance in boys to the distance between coccyx and fourchette/scrotum. 18 relevant studies were included describing the values in different ethnic groups and describing its utility. One study was excluded from statistics due to different landmark for measurement. The studies were grouped into 4. Group A:B:C:D comprised of Newborns:Infants:All age groups:Constipated children. We carried out meta-analysis to estimate effect size (mean difference) using STATA software version 16.0. The different ethnic populations in which API were measured, and were Indian (2), Turkish (3), Israel (2), Taiwanese, Thai, Iranian, Spanish, Italian, and Mexican. The API was higher by 0.129 in boys. The mean API in males was 0.53:0.54:0.48:0.52 in Group A:B:C:D with an overall mean (SD) API of 0.51 (0.04). The mean API in females was 0.40:0.40:0.38:0.37 in Group A:B:C:D with an overall mean (SD) API of 0.40(0.03). Two studies were done in mice and showed the relation of API to intrauterine exposure to androgens. In children, API was mostly used to diagnose an anterior ectopic anus and see correlation with constipation. The abnormal values varied from less than 0.30-0.34 in girls and less than 0.41-0.46 in boys. The effect size by regions showed that the estimated effect size for all the regions were within 95% Confidence limits of overall estimate (0.13: 95% CI: 0.13-0.14). Therefore, it can be inferred that there was no significant ethnic variation in the study parameter. The anal position in relation to genitalia was measured in nulliparous women, menopause women, and women with levator deficiency. It was affected in vulvovaginal atrophy. Dichlorodiphenyldichloroethylene exposure during the first trimester of pregnancy was reported to alter the anal position in male infants. The anteriorly positioned anus has been associated with constipation. API been measured in various ethnicpopulations with insignificant variations. The API issignificantly (p < 0.05) higher in males. The presence of constipation does not seem to alter API. One should adopt a single method for measurement. API should not be considered at the sole indication for any surgical intervention.

Prenatal environmental exposures and associations with teen births.

Background:Children’s prenatal exposure to multiple environmental chemicals may contribute to subsequent deficits in impulse control, predisposing them to risk-taking.Objective:Our goal was to investigate associations between prenatal exposure mixtures and risk of teen birth, a manifestation of high-risk sexual activity, among 5,865 girls (1st generation) born in southeast Massachusetts from 1992-1998.Methods:Exposures included prenatal modeled polychlorinated biphenyls (PCBs), ρ,ρ′-dichlorodiphenyl dichloroethylene (DDE), hexachlorobenzene (HCB), lead (Pb), and mercury (Hg). We fit adjusted generalized additive models with multivariable smooths of exposure mixtures, 1st generation infant’s birth year, and maternal age at 1st generation birth. Predicted odds ratios (ORs) for teen birth were mapped as a function of joint exposures. We also conducted sensitivity analyses among 1st generation girls with measured exposure biomarkers (n=371).Results:The highest teen birth risk was associated with a mixture of high prenatal HCB, Hg, Pb, and PCB, but low DDE exposure, with similar associations in sensitivity analyses. The highest OR predicted for girls born in 1995 to mothers of median age (26 years) was at the 95th percentile of the HCB and PCB exposure distributions (OR=3.09; 95% confidence interval: 0.29, 32.4). Additionally, girls born earlier in the study period or to teen mothers were at increased risk of teen birth.Significance:Prenatal environmental chemical exposures and sociodemographic characteristics may interact to substantially increase risk of teen births.

Trends in gene expression changes during adipogenesis in human adipose derived mesenchymal stem cells under dichlorodiphenyldichloroethylene exposure

Exposure to lipophilic environmental pollutants has been explored as a risk factor of development of diabetes mellitus in obese. Adipose tissue is a reservoir of bioaccumulative lipophilic contaminants including p,pʹ-dichlorodiphenyldichloroethylene (DDE). Our aim was to analyze the effect of DDE (in concentrations 0.1 μM, 1 μM, and 10 μM) on adipocyte differentiation and insulin signalling pathway on in vitro adipogenic model of human adipose derived mesenchymal stem cells (hADMSC). The effect of DDE was monitored by analysis of expression (RT qPCR, Western blotting) of genes involved in adipocyte differentiation and insulin signalling pathway including lipid metabolism on days 0, 4, 10, 21, 28 of differentiation. The main observation was significant increase of INSR, LIPE, FASN, SREBP1, OCT4 and AKT2 expression under influence of DDE. We did not record any increase of the active form of Akt. Our findings suggest that DDE exposure changes the differentiation of adipocytes, enhances the lipid metabolism and so may play a role in the development of obesity and metabolic diseases by affecting the insulin signalling pathway. The influence of DDE seems to be similar to the effect of insulin itself. However, further studies to elucidate the mechanism of action of DDE are necessary.

Using Birth Cohort Data to Estimate Prenatal Exposures for All Births around the New Bedford Harbor Superfund Site in Massachusetts

Introduction: Children born near New Bedford, Massachusetts, USA have been prenatally exposed to environmental chemicals, in part due to an older housing stock, high fish consumption rates, and proximity to the New Bedford Harbor (NBH) Superfund site. Chemical exposure measures are not available for the general population, limiting epidemiologic investigations and potential interventions. Our objective was to leverage available sociodemographic and biomonitoring data from the New Bedford Cohort (NBC) to retrospectively estimate prenatal exposures for all 10,273 births between 1993-1998 in the 4 towns neighboring the NBH Superfund site.Methods: The NBC, a population-based cohort of 788 mother-infant pairs born between 1993-1998 near the NBH, collected questionnaire data and prenatal exposure biomarkers including cord serum polychlorinated biphenyls (PCB), &amp;#961;,&amp;#961;&amp;#8242;-dichlorodiphenyl dichloroethylene (DDE), hexachlorobenzene (HCB), cord blood lead (Pb), and maternal hair mercury (Hg). We used bootstrapped samples of the NBC data to build prenatal exposure models, with multivariable smooths of birth location, birth year, maternal age at birth, and other NBC maternal sociodemographic characteristics as predictors.Results: Maternal country of birth was the strongest exposure predictor across all exposures with women from the Azores and Cape Verde having the highest levels. Maternal age, education, and marital status also were important predictors. The PCB, DDE, HCB, Pb, and Hg exposure models explained 55%, 53%, 41%, 43% and 38% of the variance, respectively.Conclusions: Our analyses suggest that multiple prenatal exposures can be estimated at the population level by modeling available data for a subset of the population. Predictive models using multivariable smoothing explained reasonable amounts of variance. Other exposure models with comparable performance have been used successfully in epidemiologic investigations to characterize exposure-outcome associations.

PRENATAL EXPOSURE TO DDE AND LOWER RESPIRATORY TRACT INFECTIONS (LRTIS) IN INFANTS: THE INMA PROJECT

Background and Aims: Growing evidence suggests that prenatal exposure to organochlorine compounds (OCs), mainly polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE), may increase the risk of respiratory infections in children through suspected immunotoxic mechanisms. Our aim is to examine, in the largest study so far, whether prenatal exposure to DDE increases the risk of LRTI in infants, and to isolate these effects from those of other OCs. Methods: The study is based on a cohort of 2150 mother-child pairs in Spain. Maternal serum concentrations of DDE and other OCs were measured during pregnancy. Parental reports of physician-confirmed diagnosis of LRTIs were obtained when children were 12-14 months old. Analyses were carried out separately for children from Spanish (N=1342) and Latin-American (N=79) mothers because of their different exposure profiles. Results: 35.4% of the children born to Spanish mothers developed at least one LRTI episode during their first 12-14 months of life. DDE exposure (median=116.3 ng/gr lipid) was associated with a higher risk of LRTIs (relative risk (95%CI) for 3rd quartile DDE exposure= 1.32 (1.08, 1.62)), which persisted after adjustment for other OCs (RR (95%CI) for 3rd quartile DDE = 1.38 (1.12, 1.71)). No association was found for other OCs. Stratified analyses showed that findings were homogeneous by study region, maternal smoking, maternal history of asthma and atopy, duration of predominant breastfeeding and maternal diet. Children born to Latin-American mothers, with much higher exposure to DDE (385.0 ng/gr lipid), showed a similar, but not statistically significant, increase in risk of LRTI with DDE exposure. Conclusions: Prenatal exposure to DDE is associated with higher risk of LRTIs in infants. Since LRTIs cause substantial morbidity in infancy and are a possible risk factor for subsequent childhood asthma, especial attention should be paid in countries where dichlorodiphenyltrichloroethane (DDT) is nowadays used for malaria control.

Dichlorodiphenyldichloroethylene exposure during the first trimester of pregnancy alters the anal position in male infants.

Anogenital distance (AGD) at birth is regarded as a useful measurement that reflects the prenatal androgenic status in rodents. However, the impact of xenoantiandrogens on human development is largely unknown. The aim of this study was to evaluate the potential antiandrogenic impact of prenatal DDT metabolites (p,p'-DDE and p,p'-DDT) exposure on infant AGD, using a non-age-dependent anal position index (API). As part of an ongoing perinatal cohort study on the effects of organochlorine pesticides in children's neurodevelopment, we conducted a cross-sectional study in 71 infants (37 males and 34 females). Maternal serum levels of DDT metabolites (p,p'-DDE and p,p'-DDT) before and during each trimester of pregnancy were determined by electron capture gas-liquid chromatography. During postnatal home visits at 3, 6, and 12 or 18 months of age, the children's weight and API were evaluated. Multiple lineal regression models were used to estimate the potential endocrine disruptor activity of prenatal p,p'-DDE exposure. Boys had significantly higher API values than girls (0.6 versus 0.5; P < 0.001). Only among boys, a doubling increase of maternal p,p'-DDE serum levels during the first trimester of pregnancy, were associated with a significant reduction of API (beta=-0.02; P= 0.02). No effect of p,p'-DDT on AGD was observed. Evidence of the effect of prenatal p,p'-DDE on external genital differentiation is scarce and not consistent in the literature. Further studies are needed to confirm a hormonal disruptive effect on the development of external genitalia, due not only to p,p'-DDE but also due to other antiandrogenic persistent compounds.

Prenatal Environment and Adult Body Composition

Past research suggests intrauterine exposure to polychlorinated biphenyls (PCB) and dichlorodiphenyl dichloroethylene (DDE) decreases birth weight and youth height and weight. However, effects of PCB and DDE on adult body size and fatness are unknown, particularly when physical activity (PA) is considered. PURPOSE: To examine the effect of birth weight and intrauterine exposure to PCB and DDE on female adult weight, body mass index (BMI), and percent body fat (%fat), and to determine if PA modifies these relationships. METHODS: Our sample included 71 female offspring from the Michigan fish-eater cohort (age =39.9±7.9 yr), with previously reported birth weights. Exposure to PCB and DDE were extrapolated backwards to date of birth from maternal serum values. A portable stadiometer and scale measured adult height and weight. BMI was calculated (kg/m2), as were % fat (skinfolds) and weekly PA (7-day recall). A median split denned LOW and HIGH active women (< and > 425 min PA/wk, respectively). Because adult data were skewed, Spearman correlations were used to analyze relationships between perinatal and adult variables. Partial correlations controlled for maternal BMI. RESULTS: Mean weight, BMI, and %fat were 74.9 ± 17.8 kg, 26.6 ±5.7 kg/m2, and 26.6 ± 6.6%, respectively. No significant correlations existed between adult body measures and prenatal PCB or DDE exposure. Within the LOW active group, birth weight was related to adult weight (r= 0.48, p=0.003) and %fat (r=0.34, p=0.048), and approached significance with BMI (r=0.32, p=0.060). These relationships did not exist for HIGH active women. After controlling for maternal BMI, birth weight was still significantly related to adult weight (r=0.52, p=0.002), BMI (r=0.36, p=0.046) and %fat (r=0.39, p=0.029) within the LOW, but not HIGH group. Compared to HIGH active women, LOW active women had significantly larger mean BMI (28.0 ± 6.6 v 25.2 ± 4.0 kg/m2) and greater %fat (28.2 ± 6.6 v 25.2 ± 6.6%, p<0.05). CONCLUSIONS: Prenatal PCB and DDE exposure are not related to female adult body size and fatness. After adjustment for confounding by maternal size, PA modified relationships between birth weight and adult weight and fatness, such that they only exist for low active women. Funded by the Agency for Toxic Substances and Disease Registry.

Maternal concentration of dichlorodiphenyl dichloroethylene (DDE) and initiation and duration of breast feeding

Dichlorodiphenyl dichloroethylene (DDE) has been shown to reduce the duration of breast feeding in two studies. In addition to duration, we examined whether DDE lowers the initiation of breast feeding. Between 1973 and 1991, the Michigan Department of Community Health conducted three surveys to assess polychlorinated biphenyls (PCBs) and DDE serum concentrations in Michigan anglers. Through telephone interviews with parents, we retrospectively ascertained information on breast feeding. Based on repeated maternal serum measurements between 1973 and 1991, we arrived at the level of exposure at the time of delivery by extrapolating PCB and DDE serum levels. One mother may have contributed more than one child; however, serum concentrations varied between children from the same mother. The maternal DDE and PCB serum concentrations were categorised as follows: 0 to <5 microg/L, 5 to <10 microg/L, >or=10 microg/L. Repeated measurement models and survival analyses were used to determine the relationship between DDE and PCBs and characteristics of breast feeding while controlling for cohort effects, maternal age at delivery, education, and smoking during pregnancy. We focused on 176 pregnancies of 91 mothers who had maternal exposure information and gave birth between 1969 and 1995. Initiation of breast feeding was lowered by 39.5% and duration shortened by 66.4% in children of mothers who smoked during pregnancy. In children of non-smoking mothers, the incidence ratio for breast-feeding initiation was 0.45 [95% CI 0.15, 0.94] and 0.42 [95% CI 0.10, 1.03] when maternal DDE concentrations were 5 to <10 microg/L and >or=10 microg/L respectively, compared with the lowest DDE exposure group. In these offspring (of non-smoking mothers), breast-feeding duration was shorter when DDE concentrations were higher: 13 weeks for >or=10 microg/L DDE, compared with 21.7 weeks for lower DDE. We did not detect any association between PCBs and breast feeding. In the absence of the distorting effects of maternal smoking, DDE exposure may decrease initiation and duration of breast feeding.

Maternal exposure to Great Lakes sport-caught fish and dichlorodiphenyl dichloroethylene, but not polychlorinated biphenyls, is associated with reduced birth weight

Fish consumption may be beneficial for a developing human fetus, but fish may also contain contaminants that could be detrimental. Great Lakes sport-caught fish (GLSCF) are contaminated with polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE), but the effects of these contaminants on birth outcome are not clear. To distinguish potential contaminant effects, we examined (1) whether the decrease over time in contaminant levels in GLSCF is paralleled by an increase in birth weight of children of GLSCF-consuming mothers and (2) the relation between maternal serum concentrations of these contaminants and birth weight. Mothers (n=511) were interviewed from 1993 to 1995, and maternal serum was collected from 1994 to 1995 (n=143). Potential confounders considered were child gender, maternal age at delivery, maternal prepregnancy body mass index, maternal cigarette and alcohol use during pregnancy, maternal education level, maternal parity, and maternal breastfeeding. Children born during 1970–1977, 1978–1984, and 1985–1993 to mothers who ate more than 116 meals of GLSCF before pregnancy were, on average, 164g lighter, 46g heavier, and 134g heavier, respectively, than children of mothers who ate no GLSCF before pregnancy (P trend=0.05). GLSCF-consuming mothers had higher serum PCB and DDE concentrations, but only increased DDE was associated with lower birth weight. The data suggest that fetal DDE exposure (as indicated by maternal serum DDE concentration) may decrease birth weight and that decreased birth weight effects associated with GLSCF consumption have decreased over time.