Decoding historical and emerging environmental concerns of C6-36 chlorinated paraffins: Insights from marine sediment cores in the Pearl River Estuary

Yetong Shao; Qi Wang; Kendric Aaron Tee; Linjie Jin; Xiaoqiang Yang; Yuanyuan Hong; He Wang; Akira Tsujimoto; Moriaki Yasuhara; Kenneth M Y Leung; Paul K S Lam; Yuefei Ruan

doi:10.1016/j.envpol.2024.125435

Decoding historical and emerging environmental concerns of C_6-36 chlorinated paraffins: Insights from marine sediment cores in the Pearl River Estuary

Environ Pollut. 2024 Nov 30:366:125435. doi: 10.1016/j.envpol.2024.125435. Online ahead of print.

Authors

Yetong Shao¹, Qi Wang², Kendric Aaron Tee³, Linjie Jin¹, Xiaoqiang Yang⁴, Yuanyuan Hong⁵, He Wang⁵, Akira Tsujimoto⁶, Moriaki Yasuhara⁵, Kenneth M Y Leung⁷, Paul K S Lam⁸, Yuefei Ruan⁹

Affiliations

¹ State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China.
² State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China.
³ State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China.
⁴ Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China.
⁵ School of Biological Sciences, Area of Ecology and Biodiversity, Swire Institute of Marine Science, Institute for Climate and Carbon Neutrality and Musketeers Foundation Institute of Data Science, The University of Hong Kong, Hong Kong, 999077, China.
⁶ Institute of Education, Academic Assembly, Shimane University, Shimane, 690-8504, Japan.
⁷ State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China; School of Energy and Environment, City University of Hong Kong, Hong Kong, 999077, China; Department of Chemistry, City University of Hong Kong, Hong Kong, 999077, China.
⁸ State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China; Department of Chemistry, City University of Hong Kong, Hong Kong, 999077, China; Department of Applied Science, School of Science and Technology, Hong Kong Metropolitan University, Hong Kong, 999077, China.
⁹ State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China; Department of Chemistry, City University of Hong Kong, Hong Kong, 999077, China. Electronic address: yruan8@cityu.edu.hk.

PMID: 39622407
DOI: 10.1016/j.envpol.2024.125435

Abstract

Chlorinated paraffins (CPs) readily deposit in sediments upon entering estuaries and adjacent seas. Time-series investigations are indispensable for the long-term monitoring of historical releases and identifying CPs of emerging concerns in the marine environment. In this study, short-, medium-, and long-chain CPs (SCCPs, MCCPs, and LCCPs) were investigated using time-of-flight high-resolution mass spectrometry (ToF-HRMS) in sediment cores, dated between the 1920s and the 2010s sampled from Hong Kong waters and Lingdingyang of the Pearl River Estuary (PRE), South China. Levels of SCCPs remained steady since the 1980s, while increasing trends of MCCPs and LCCPs were observed, indicating a market supply shift from SCCPs to MCCPs and LCCPs, potentially influenced by global restrictions. This is the first study to report C_18-31 CPs in Chinese marine sediments. C_>₂₀ very long-chain CPs (C_>₂₀ vLCCPs) subcategorized from LCCPs were semi-quantified via ToF-HRMS and positively correlated with those of other CP categories, implying their synchronized release in the investigated regions. C_>₂₀ vLCCPs, contributing an average of 27% of total CP concentrations in two cores, were found at higher levels than LCCPs (7%). Hence, the risk of C_>₂₀ vLCCP contamination should not be ignored. By highlighting the temporal variations in the world's largest producer and consumer of CPs, the present study augments the database of the continuous deposition of SCCPs and MCCPs in marine sediments in the PRE and highlights the unrecognized risks of LCCP contaminations.

Keywords: Greater bay area; Polychlorinated n-alkanes; Temporal trend; vLCCPs; vSCCPs.