Serum Concentrations of Selected Persistent Organic Pollutants in a Sample of Pregnant Females and Changes in Their Concentrations during Gestation

Abstract

Objectives In this study we evaluated the concentrations of selected persistent organic pollutants in a sample of first-time pregnant females residing in the United States and assessed differences in these concentrations in all pregnant females during gestation. Methods We reviewed demographic and laboratory data for pregnant females participating in the National Health and Nutrition Examination Survey, including concentrations of 25 polychlorinated biphenyls (PCBs), 6 polychlorinated dibenzo- p -dioxins (PCDDs), 9 polychlorinated dibenzofurans (PCDFs), and 9 organochlorine pesticides. We report serum concentrations for first-time pregnant females (2001–2002; n = 49) and evaluate these concentrations in all pregnant females by trimester (1999–2002; n = 203) using a cross-sectional analysis. Results The chemicals with ≥ 60% detection included PCBs (congeners 126, 138/158, 153, 180), PCDDs/PCDFs [1,2,3,4,6,7,8-heptachlorodibenzo- p -dioxin (1234678HpCDD), 1,2,3,6,7,8-hexachlorodibenzo- p -dioxin (123678HxCDD), 1,2,3,4,6,7,8-heptachlorodibenzofuran (1234678HpCDF), 1,1′-(2,2-dichloroethenylidene)-bis(4-chlorobenzene) ( p , p ′-DDE)], and trans -nonachlor. The geometric mean concentration (95% confidence intervals) for 1234678HpCDD was 15.9 pg/g lipid (5.0–50.6 pg/g); for 123678HxCDD, 9.7 pg/g (5.5–17.1 pg/g); and for 1234678HpCDF, 5.4 pg/g (3.3–8.7 pg/g). The differences in concentrations of these chemicals by trimester were better accounted for with the use of lipid-adjusted units than with whole-weight units; however, the increase in the third-trimester concentration was greater for PCDDs/PCDFs (123678HxCDD, 1234678HpCDF) than for the highest concentration of indicator PCBs (138/158, 153, 180), even after adjusting for potential confounders. Conclusion The concentrations of these persistent organic pollutants in a sample of first-time pregnant females living in the United States suggest a decline in exposures to these chemicals since their ban or restricted use and emission. The redistribution of body burden for these and other persistent organic pollutants during pregnancy needs to be more carefully defined to improve the assessment of fetal exposure to them based on maternal serum concentrations. Additional studies are needed to further the understanding of the potential health consequences to the fetus from persistent organic pollutants.

Persistent organic pollutant concentrations in first birth mothers across Mexico

“…This might be expected, as the breast cancer cases and controls are older than the mothers in this study, and concentrations of PCBs in human beings are decreasing in many parts of the world over the time period between these two studies. Concentrations of PCBs 138, 153 and 180 in Mexican primiparous mothers were close to one quarter to those seen in the United States primiparous mothers as reported by Wang et al (2009), even although the age range were similar in both the studies. This difference could be because NHANES (1999)(2000)(2001)(2002)) was conducted at a time when PCB concentrations in the environment were higher, hence, the women had higher exposures to PCBs.…”

“…Organochlorine pesticides, PCBs, PCDDs and PCDFs accumulating in the maternal body are transferred to the fetus via placenta during the pregnancy or to the infants via maternal milk; therefore, the pregnant woman's body burden is important because of the higher exposures and the potential health effects in the fetuses and infants. (Todaka et al, 2010;Wang et al, 2009).…”

Prenatal exposure to DDT in malaria endemic region following indoor residual spraying and in non-malaria coastal regions of South Africa

“…However, it is difficult to directly compare our results with those studies as a source of exposure in malaria areas is IRS with DDT (Wang et al, 2009;Weldon et al, 2010).…”

Effects of Prenatal Exposure to Endocrine Disruptors and Toxic Metals on The Fetal Epigenome

“…Research has demonstrated that PCB levels are higher than expected in fetal tissues based on passive diffusion alone, suggesting an active transport mechanism across the placenta [72]. Moreover, biomonitoring of pregnant women suggests that serum levels of PCB may increase over the course of pregnancy as lipid stores are mobilized [99]. Results from the NCS did not identify a relationship between LUMA methylation in the placenta and placental PCB levels [94].…”

“…Dichlorodiphenyldichloroethylene (DDE), a common breakdown product of DDT that may form in the environment or within the body, is often examined alongside DDT as it has been associated with adverse health outcomes in human populations [85,86]. While DDT and DDE both have long half-lives in the environment and the human body, DDE was observed to be the predominant form found in pregnant women participating in the National Health and Nutrition Examination Survey [87]. While levels of DDT are lower within fetal than maternal tissues, there is evidence that DDT is actively transported across the placenta as fetal levels are higher than expected via passive diffusion [72].…”