Association between Several Persistent Organic Pollutants and Thyroid Hormone Levels in Cord Blood Serum and Bloodspot of the Newborn Infants of Korea.

Sunmi Kim,Su Young Kim,Sungkyoon Kim,Sungjoo Kim,Hyo-Bang Moon,Jeong Jae Lee,Kyungho Choi,Gyuyeon Choi,Jeongim Park,Hai-Joong Kim,Sooran Choi,Aimin Chen

doi:10.1371/journal.pone.0125213

Abstract

Current knowledge on adverse endocrine disruption effects of persistent organic pollutants (POPs) among newborn infants is limited and often controversial. To investigate the associations between prenatal exposure to major POPs and thyroid hormone levels among newborn infants, both cord serum or maternal serum concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) were compared with five thyroid hormones in cord serum of newborn infants as well as TSH in bloodspot collected at 2 day after birth (n=104). Since cord serum thyroid hormones could be affected by those of mothers, thyroid hormone concentrations of the matching mothers at delivery were adjusted. In cord serum, BDE-47, -99, and Σchlordane (CHD) showed significant positive associations with cord or bloodspot TSH. At the same time, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorbenzene (HCB) showed negative associations with total T3 and total T4 in cord serum, respectively. Maternal exposure to β-hexachlorhexane (β-HCH), ΣCHD, ΣDDT, or p,p'-DDE were also associated with neonatal thyroid hormones. Although the sample size is small and the thyroid hormone levels of the subjects were within the reference range, our observation supports thyroid disrupting potential of several POPs among newborn infants, at the levels occurring in the general population. Considering the importance of thyroid hormones during gestation and early life stages, health implication of thyroid hormone effects by low level POPs exposure deserves further follow up investigations.

Highlights

Persistent organic pollutants (POPs) have been detected in various environmental media and biota worldwide, even though many of these compounds including organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs), had been banned for use several decades ago
Polybrominated diphenyl ethers (PBDEs) are a group of emerging POPs that have been relatively recently recognized for widespread contamination and adverse health effects [3, 4]
Because cord serum thyroid levels can be affected by the maternal input of thyroid hormones [34, 35], and we found that the levels of free/total T4 and total T3 were positively correlated with its counterpart between maternal and cord serum in the Chemicals in Korea (CHECK) population, respective thyroid hormone concentrations of the matching mother were added into the model

Summary

Introduction

Persistent organic pollutants (POPs) have been detected in various environmental media and biota worldwide, even though many of these compounds including organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs), had been banned for use several decades ago. Polybrominated diphenyl ethers (PBDEs) are a group of emerging POPs that have been relatively recently recognized for widespread contamination and adverse health effects [3, 4]. In both wildlife and humans, adverse reproductive, developmental, neurologic, and endocrine health effects have been well-documented for many POPs [5]. The exposure to chemicals including POPs among developing fetus has been suggested to be linked to the adverse health effects of later stages of life [11, 12]

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