Occurrence and exposure risk evaluation of polyhalogenated carbazoles (PHCZs) in drinking water

Guowei Wang; Timing Jiang; Sen Li; Huijie Hou; Keke Xiao; Jingping Hu; Sha Liang; Bingchuan Liu; Jiakuan Yang

doi:10.1016/j.scitotenv.2020.141615

Occurrence and exposure risk evaluation of polyhalogenated carbazoles (PHCZs) in drinking water

Sci Total Environ. 2021 Jan 1:750:141615. doi: 10.1016/j.scitotenv.2020.141615. Epub 2020 Aug 13.

Authors

Guowei Wang¹, Timing Jiang¹, Sen Li², Huijie Hou¹, Keke Xiao¹, Jingping Hu¹, Sha Liang¹, Bingchuan Liu¹, Jiakuan Yang³

Affiliations

¹ School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, PR China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Wuhan 430074, PR China.
² School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, PR China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Wuhan 430074, PR China; Environmental Change Institute, University of Oxford, Oxford OX1 3QY, UK.
³ School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, PR China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Wuhan 430074, PR China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology (HUST), Wuhan 430074, PR China. Electronic address: jkyang@mail.hust.edu.cn.

PMID: 32858294
DOI: 10.1016/j.scitotenv.2020.141615

Abstract

Although polyhalogenated carbazoles (PHCZs) can be generated and detected in drinking water, their occurrence and potential health risks to humans via drinking water ingestion are not well known. In this study, 11 PHCZs were screened in drinking water samples from Wuhan, the most populous city in central China. The total concentration of PHCZs could be up to 53.48 ng/L with a median level of 8.19 ng/L, which was comparable to polychlorinated biphenyls and poly- and perfluoroalkyl substances reported in the literatures for drinking water. Composition profiles revealed that 3,6-dichlorocarbazole, 3-chlorocarbazole, 3-bromocarbazole and 3,6-dibromocarbazole were the predominant PHCZ congeners in the tested samples. Regional differences in the levels and patterns of PHCZs suggested that anthropogenic releases should be the dominant source compared to natural generation. Boiling of the water samples caused no significant change in PHCZs concentrations after correcting the volume change due to evaporation. Potential health risks associated to the levels of PHCZs in drinking water were assessed using the toxic equivalent (TEQs) method. The estimated daily intake of PHCZs via drinking water ingestion is up to 0.38 pg-TEQ/kg body weight/day for infants, nearly 4.5 times higher than that for adults, and appears to reach the maximum permissible concentration set by certain authority agencies. Overall, drinking water ingestion represents an important exposure pathway for PHCZs. This is the first comprehensive study on the abundance and health risks of PHCZs in drinking water.

Keywords: Composition profile; Halogenated carbazoles; Health risks; Regional differences; Toxic equivalent.

MeSH terms

Carbazoles
China
Drinking Water*
Polychlorinated Biphenyls*
Water Pollutants, Chemical* / analysis

Substances

Carbazoles
Drinking Water
Water Pollutants, Chemical
Polychlorinated Biphenyls