摘要
全氟烷基酸(PFAAs)是一类在水环境中广泛存在的有机污染物,具有潜在的生物累积性和多种生物毒性.为探究长链PFAAs与其短链替代品在浮游动物大型溞体内的竞争富集作用,通过比较典型长链PFAAs存在和不存在两个暴露条件下短链PFAAs在大型溞体内的生物富集,考察PFAAs在大型溞体内的吸收速率常数(ku)、排出速率常数(ke)和稳态生物浓缩系数(BCFss)等指标的变化规律,探讨典型长链PFAAs与其短链替代品的竞争富集作用机制.结果表明,PFAAs在大型溞体内的ku和BCFss值分别与全氟碳原子数、膜−水分配系数和蛋白质结合系数显著正相关,且长链PFAAs对短链PFAAs的生物富集具有明显抑制作用,导致短链PFAAs的BCFss值降低56%~80%.长链与短链PFAAs在蛋白质结合点位的竞争作用可能是短链PFAAs生物富集受到抑制的机制之一.
Perfluoroalkyl acids(PFAAs)are a class of ubiquitous organic pollutants in aquatic environment.The PFAAs can be accumulated in various organisms,and thus induce diverse toxic effects.By studying the bioconcentration of short-chain PFAAs in Daphnia magna under exposure conditions with and without long-chain PFAAs,we herein analyzed the uptake rate constant(ku),elimination rate constant(ke),and bioconcentration factors at steady state(BCFss)of PFAAs in Daphnia magna,and subsequently attempted to uncover mechanisms underpinning the influence of long-chain PFAAs on shorter chain PFAA bioaccumulation.It revealed positive linear associations between ku or BCFss and the numbers of perfluorinated carbon,membrane-water distribution coefficients,protein-water distribution coefficients,and PFAA-protein association constants.Moreover,longer chain PFAAs inhibited the bioconcentration of shorter chain PFAAs,reducing the BCFss to 56%~80%.Such a reduction would be caused by competitive binding to proteins between longer and shorter chain PFAAs.
作者
肖璐
张尚伟
程浩
于丹凤
姜晓满
胡蝶旋
文武
夏星辉
XIAO Lu;ZHANG Shang-wei;CHENG Hao;YU Dan-feng;JIANG Xiao-man;HU Die-xuan;WEN Wu;XIA Xing-hui(Instrumentation and Service Center for Science and Technology,Beijing Normal University,Zhuhai 519087,China;Key Laboratory of Water and Sediment Sciences of Ministry of Education,School of Environment,Beijing Normal University,Beijing 100875,China;Advanced Interdisciplinary Institute of Environment and Ecology,Beijing Normal University,Zhuhai 519087,China;College of Environment Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2024年第1期489-498,共10页
China Environmental Science
基金
国家自然科学基金资助项目(42007348,T2261129474,52039001,52270148)
环境模拟与污染控制国家重点实验室自由课题(22Z01ESPCW)。
