Effect of aging on bioaccessibility of DDTs and PCBs in marine sediment

CORC > 生态环境研究中心 > 中国科学院生态环境研究中心 > 环境化学与生态毒理学国家重点实验室

	Effect of aging on bioaccessibility of DDTs and PCBs in marine sediment
	Taylor, Allison R.; Wang, Jie ; Liao, Chunyang ; Schlenk, Daniel ; Gan, Jay
刊名	ENVIRONMENTAL POLLUTION
	2019-02
卷号	245 页码:582-589
关键词	Bioavailability Hydrophobic organic contaminants Aging effect Tenax desorption Legacy contaminants
ISSN号	0269-7491
英文摘要	Hydrophobic legacy contaminants like dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs) were banned almost half a century ago. While their residues still remain in many environmental compartments, they have undergone extensive aging and likely have lower bioaccessibility (the available fraction) compared to fresh residues. However, risk assessment relies heavily on the use of total chemical concentration, rather than accounting for age-diminished bioaccessibility, likely leading to overestimated risks. in this study, we used 24 h Tenax desorption to measure the potential bioaccessibility of DDTs and PCBs in two sediment cores taken from the Palos Verdes Shelf Superfund site in the Pacific Ocean. The total concentrations of DDTs and PCBs from the core located at the sewage outfall (8C) were as high as 41,000-15,700 mu g/kg (dry weight, dw) and 530-2600 mu g/kg dw, respectively, while those from a location 7 km northeast of the outfall (3C) were 2-3 orders of magnitude lower. Bio-accessibility estimated by 24-h Tenax-aided desorption (F-24h) decreased in the order of DDD > DDE > DDT for DDT derivatives, and PCB 52 > PCB 70 > PCB 153 for PCB congeners, showing a negative correlation with their log K-ow. Due to the extensive aging, F-24h values were <20% of the total chemical concentration for most contaminants and <5% for DDT, DDE and PCB 153, suggesting that aging greatly diminished their bioavailability. However, a quantitative relationship between F-24h and sediment age along the vertical profile was not found, likely because the contaminant residues had undergone aging before their offsite transport and deposition onto the ocean floor. As the use of man-made chemicals such as DDT and PCBs was discontinued in the U.S. many decades ago, the reduction in their bioavailability due to aging may be universal and should be taken into consideration to avoid overly conservative risk predictions or unnecessary mitigation interventions. (C) 2018 Elsevier Ltd. All rights reserved.
内容类型	期刊论文
源URL	[http://ir.rcees.ac.cn/handle/311016/42933]
专题	生态环境研究中心_环境化学与生态毒理学国家重点实验室
作者单位	1.Univ Calif Riverside, Dept Environm Sci, Riverside, CA 92521 USA 2.Chinese Acad Sci, State Key Lab Environm Chem & Ecotoxicol, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China
推荐引用方式 GB/T 7714	Taylor, Allison R.,Wang, Jie,Liao, Chunyang,et al. Effect of aging on bioaccessibility of DDTs and PCBs in marine sediment[J]. ENVIRONMENTAL POLLUTION,2019,245:582-589.
APA	Taylor, Allison R.,Wang, Jie,Liao, Chunyang,Schlenk, Daniel,&Gan, Jay.(2019).Effect of aging on bioaccessibility of DDTs and PCBs in marine sediment.ENVIRONMENTAL POLLUTION,245,582-589.
MLA	Taylor, Allison R.,et al."Effect of aging on bioaccessibility of DDTs and PCBs in marine sediment".ENVIRONMENTAL POLLUTION 245(2019):582-589.