Thyroid-disrupting effects caused by exposure to alternative flame retardants from groundwater contamination in rural central China

TY - JOUR

T1 - Thyroid-disrupting effects caused by exposure to alternative flame retardants from groundwater contamination in rural central China

AU - Han, Fengchan

AU - Chen, Guanghua

AU - Tao, Gonghua

AU - Xu, Jingshan

AU - Zhang, Huijun

AU - Zhang, Ling

AU - Li, Hongliang

AU - Zhao, Yijing

AU - Tian, Dajun

AU - Kimura, Susana Y.

AU - Wei, Xiao

AU - Ruan, Yuanyuan

AU - Wu, Chunfeng

AU - Xiao, Shuo

AU - Zhan, Ming

AU - Zheng, Weiwei

N1 - Funding Information: This work was supported by the National Natural Science Foundation of China (Nos. 81773379 & 82122058 & 81202165 ), Key Young Talents Training Program for Shanghai Disease Control and Prevention ( 21QNGG10 ), and the Second Cohort of the “QingGeng” Plan of the Shanghai Municipal Center for Disease Control and Prevention (No. 2021-26 ), the Shanghai Municipal Commission of Health and the Family Foundation for Fifth Round of the Three-Year Public Health Action Plan of Shanghai ( GWV-1.1 & GWV-10.1-XK11 ), for General Program ( 202040186 ) and for Young Talents ( 2017YQ023 ), the Natural Science Foundation of Shanghai ( 21 ZR1438400 ) and the Public Health Discipline Construction of Pudong New Area Health System ( PWGw2020-04 ). Publisher Copyright: © 2022

PY - 2022/9/15

Y1 - 2022/9/15

N2 - Accumulating evidence reveals that exposure to alternative flame retardants (AFRs) results in defective thyroid functions. AFRs are detectable in various environmental media in developed cities in China. However, few studies have reported the contamination levels of AFR in groundwater in rural areas, indicating an urgent need to investigate exposure of AFRs and perform health risk assessment for populations that use groundwater as the main source of drinking water. This study investigated the concentrations of AFRs in groundwater in rural areas of central China. Moreover, Nthy-ori-3-1 cells were used to determine the thyroid cytotoxicities and thyroid–interfering effects of a single AFR as well as the mixtures of AFRs based on the AFR contamination levels in real-world. The results revealed that all classes of AFRs were detectable in rural areas in central China. Dechlorane plus, hexabromocyclododecane, bromophenols (BPs), novel brominated flame retardants (NBFRs) and organophosphate flame retardants (OPFRs) exhibited spatial contamination patterns, with an average concentrations (median) of 157.89 ± 88.61 (185.47) pg/L, 0.09 ± 0.29 (not detectable) ng/L, 5.20 ± 5.92 (3.43) ng/L, 3338.11 ± 3758.78 (2836.72) pg/L, and 79.35 ± 97.19 (53.62) ng/L, respectively. The half maximal effective concentrations (EC50) of BPs, OPFRs, and NBFRs ranged 98.4–4012 μM, 42.0–2506 μM, and 10.1–203.7 μM, respectively. Several AFRs exhibited more cytotoxic effects than did traditional brominated flame retardants. It is intriguing that several single AFRs and mixtures at environmentally-relevant exposure levels promoted the viability of Nthy-ori-3-1 cells. Taken together, our study demonstrates that AFRs are present in the groundwater in rural areas in central China and AFRs exhibit thyroid disrupting effects.

AB - Accumulating evidence reveals that exposure to alternative flame retardants (AFRs) results in defective thyroid functions. AFRs are detectable in various environmental media in developed cities in China. However, few studies have reported the contamination levels of AFR in groundwater in rural areas, indicating an urgent need to investigate exposure of AFRs and perform health risk assessment for populations that use groundwater as the main source of drinking water. This study investigated the concentrations of AFRs in groundwater in rural areas of central China. Moreover, Nthy-ori-3-1 cells were used to determine the thyroid cytotoxicities and thyroid–interfering effects of a single AFR as well as the mixtures of AFRs based on the AFR contamination levels in real-world. The results revealed that all classes of AFRs were detectable in rural areas in central China. Dechlorane plus, hexabromocyclododecane, bromophenols (BPs), novel brominated flame retardants (NBFRs) and organophosphate flame retardants (OPFRs) exhibited spatial contamination patterns, with an average concentrations (median) of 157.89 ± 88.61 (185.47) pg/L, 0.09 ± 0.29 (not detectable) ng/L, 5.20 ± 5.92 (3.43) ng/L, 3338.11 ± 3758.78 (2836.72) pg/L, and 79.35 ± 97.19 (53.62) ng/L, respectively. The half maximal effective concentrations (EC50) of BPs, OPFRs, and NBFRs ranged 98.4–4012 μM, 42.0–2506 μM, and 10.1–203.7 μM, respectively. Several AFRs exhibited more cytotoxic effects than did traditional brominated flame retardants. It is intriguing that several single AFRs and mixtures at environmentally-relevant exposure levels promoted the viability of Nthy-ori-3-1 cells. Taken together, our study demonstrates that AFRs are present in the groundwater in rural areas in central China and AFRs exhibit thyroid disrupting effects.

KW - Alternative flame retardants

KW - Detection concentration

KW - Groundwater

KW - Rural areas

KW - Thyroid cytotoxicities

KW - Thyroid-disrupting effects

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U2 - https://doi.org/10.1016/j.scitotenv.2022.156300

DO - https://doi.org/10.1016/j.scitotenv.2022.156300

M3 - Article

C2 - 35636535

SN - 0048-9697

VL - 839

JO - Science of the Total Environment, The

JF - Science of the Total Environment, The

M1 - 156300

ER -