摘要
圈养是保护极度濒危物种-扬子鳄的重要手段,但圈养环境中滴滴涕(DDT)等污染物可能对扬子鳄产生毒害作用.本研究测试了我国最大的扬子鳄圈养基地水塘沉积物中DDT及其降解产物的含量和组成,并评估了这些污染物的潜在生态风险.沉积物中∑DDXs(DDT及其降解产物含量之和)的含量范围为4.30-11.9 ng·g;干重;秋季含量显著高于春季. p,p’-DDE是最主要的DDT类污染物,其含量占∑DDXs的73%. DDT的两种高阶降解产物2-氯-1,1-双(4-氯苯基)乙烯(p,p’-DDMU)和1-氯-4-[(4-氯苯基)甲基]苯(p,p’-DDM)也在沉积物中广泛检出,其含量分别占∑DDXs的6.5%和0.5%. DDT类污染物的组成分析结果显示,圈养扬子鳄栖息地没有DDT的新源输入.沉积物中DDE和DDT的含量超过了这些污染物的阈值效应水平,表明圈养扬子鳄栖息水塘中这些化学品存在潜在的生态风险.
Captive breeding of the Chinese alligator serves as the last resort for ex situ conservation of this critically endangered species. However, this effort may be compromised by the environmental chemicals such as DDT-related compounds which are proposed stressors contributing to the declines in some crocodilian populations. Here, we reported the presence of DDT and its metabolites in the sediments from the largest captive breeding center for the Chinese alligator in China. The concentrations of ∑DDXs(sum of the concentrations of DDT and its metabolites) in the sediments ranged from 4.30 to 11.9 ng·g;dry weight, with significantly higher levels in autumn than spring.The most abundant DDT compound in the sediments was p,p’-DDE, comprising approximately 73%of the ∑DDXs. In particular, two high-order metabolites of DDT, p,p’-DDMU and-DDM, were also consistently detected in the sediments, with contributions of 6.5% and 0.5% to the ∑DDXs,respectively. The profiles of DDT isomers and its metabolites indicated that there is no DDT fresh input in the captive breeding center. The concentrations of DDE and DDT in the sediment samples clearly exceeded the threshold effects level set in sediment quality guidelines, suggesting potential ecological risks of these chemicals.
作者
吴思康
徐雅纯
冯文露
胡钰
聂佑恬
李肖
吴江平
麦碧娴
WU Sikang;XU Yachun;FENG Wenlu;HU Yu;NIE Youtian;LI Xiao;WU Jiangping;MAI Bixian(School of Ecology and Environment,Anhui Normal University,Wuhu,241002,China;State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou,510640,China)
出处
《环境化学》
CAS
CSCD
北大核心
2021年第11期3406-3412,共7页
Environmental Chemistry
基金
安徽省自然科学基金(2008085MD123)
有机地球化学国家重点实验室开放基金(SKLOG-201714)资助。
