Prenatal exposure to emerging and traditional organophosphate flame retardants: Regional comparison, transplacental transfer, and birth outcomes

Wangwang Luo; Yingxue Liu; Xiaomeng Yang; Muhammed Aamir; Xiaoxia Bai; Weiping Liu

doi:10.1016/j.envpol.2023.122463

Prenatal exposure to emerging and traditional organophosphate flame retardants: Regional comparison, transplacental transfer, and birth outcomes

Environ Pollut. 2023 Nov 1:336:122463. doi: 10.1016/j.envpol.2023.122463. Epub 2023 Sep 3.

Authors

Wangwang Luo¹, Yingxue Liu¹, Xiaomeng Yang¹, Muhammed Aamir², Xiaoxia Bai³, Weiping Liu⁴

Affiliations

¹ MOE Key Laboratory of Environmental Remediation and Ecosystem Health, Institute of Environmental Health, Zhejiang University, Hangzhou, 310058, China.
² Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, Interdisciplinary Research Academy (IRA), Zhejiang Shuren University, Hangzhou, 310015, China.
³ Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310006, China.
⁴ MOE Key Laboratory of Environmental Remediation and Ecosystem Health, Institute of Environmental Health, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, Interdisciplinary Research Academy (IRA), Zhejiang Shuren University, Hangzhou, 310015, China. Electronic address: wliu@zju.edu.cn.

PMID: 37669697
DOI: 10.1016/j.envpol.2023.122463

Abstract

During gestation, organophosphate flame retardants (OPFRs) have the potential to pose health risks to fetuses due to their ability to cross the placental barrier. However, data are scarce regarding the transplacental transfer of these compounds, particularly concerning emerging OPFRs and regional variations. In this study, we analyzed 14 traditional OPFRs and 5 emerging OPFRs in maternal and cord serum samples from Mianyang and Hangzhou, two cities in eastern and western China, respectively. The results revealed marked disparities in the overall levels of OPFRs between the two cities (p < 0.05), with the average concentration in maternal serum being higher in Hangzhou (14.55 ng/mL) than in Mianyang (8.28 ng/mL). The most abundant compounds found in both cities were tris (2-chloroethyl) phosphate (TCEP), Triphenyl phosphate (TPHP), and Tri-n-butyl phosphate (TnBP). Additionally, this study marked the first detection of novel OPFRs, including resorcinol bis (diphenyl phosphate) (RDP), isodecyl diphenyl phosphate (IDDPP), cresyl diphenyl phosphate (CDP), and bisphenol A bis (diphenyl phosphate) (BPA-BDPP) in maternal and cord serum simultaneously with the detection frequencies higher than 45%. This study also found that transplacental transfer efficiencies for OPFRs varied by ester group, with Aryl-OPFRs exhibiting the highest transfer rates (0.90-1.11) and Alkyl-OPFRs exhibiting the lowest (0.66-0.83). Transfer efficiencies exhibited a positive correlation with log K_ow values (p < 0.05), suggesting that hydrophobic OPFRs with higher log K_ow values are more likely to permeate the placental barrier. Moreover, the exposure levels of Tris (1,3-dichloro-2-propyl) phosphate (TDCIPP), Tri (Chloropropyl) Phosphate (TCIPP), TPHP, and CDP in cord serum were negatively associated (p < 0.05) with birthweight of newborns. This research adds to our understanding of the transplacental transfer of OPFRs and the possible health risks associated with prenatal exposure.

Keywords: Emerging OPFRs; Exposure; Organophosphate flame retardant; Transplacental transfer.

MeSH terms

Female
Flame Retardants*
Humans
Infant, Newborn
Organophosphates
Organophosphorus Compounds
Phosphates
Placenta
Pregnancy
Prenatal Exposure Delayed Effects*

Substances

Flame Retardants
diphenyl
triphenyl phosphate
tris(chloroethyl)phosphate
Organophosphates
Phosphates
Organophosphorus Compounds