Ecological risk assessment of organochlorine pesticide mixture in South China Sea and East China Sea under the effects of seasonal changes and phase-partitioning. (December 2022)

• Record Type: Journal Article
• Authors: Wang, Ce; Feng, Lan; Thakuri, Bikash; Chakraborty, Amit
• Is Part Of: Marine pollution bulletin. Volume 185:Part A(2022)
• Publication Date: 2022-12
• Subjects: Organochlorine pesticides -- South China Sea -- Mixing risk quotient -- Phase partitioning -- East China Sea; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2022.114329
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: Organochlorine pesticides (OCPs), chlorinated hydrocarbon derivatives extensively used in agriculture and chemical industry, have been banned for several decades in most developed countries. However, OCPs act as persistent organic pollutants due to their semi-volatility nature, high ability for wide range transportation and faster bioaccumulation, and thus it has remained as a topical global concern. This study focuses on OCP distributions, sources and associated ecological risks in the globally important OCP source-sink regions of South China Sea (SCS) and East China Sea (ECS). Given the co-exposure of multiple OCPs that undermine the classical risk assessment of single OCP species, a two-tier mixture risk assessment approach has been employed with explicit consideration of seasonal changes and phase-partitioning effects. The results indicate existence of multiple sources varied across the seasons and between the dissolved and particulate phases. Potential sources include the current-use of lindane or historical use of technical HCH, input of technical DDTs, long-range atmospheric transport, and deposition of HCB from land surfaces. There are no wide high-risk zones. Dissolved HCB and DDTs have posed low-to-medium levels of risks broadly distributed across the seasons. Relatively greater risks are observed in summer in the both dissolved and particulate phases. The study has shown the importance of considering mixture risk assessments with the effects of phase-partitioning and seasonal changes for efficient oceanic risk management. Graphical abstract: Unlabelled Image Highlights: OCPs display high spatiotemporal variations. Potential sources include lindane, historical use of technical HCH and DDTs. Dissolved HCB, DDT have posed low-to-medium levels of ecological risks. Particulate DDTs have exhibited significant risk only in summer season. Very few spots showed HCB and DDT-posed high-risk sensitive to algae and daphnia .