Influence of dissolved organic carbon on multimedia distribution and toxicity of fipronil and its transformation products in lotic waterways  

作　　者：Weizong Li Hao Hu Fen Liu Huizhen Li Jing You 

机构地区：[1]School of Environment and Guangdong Key Laboratory of Environmental Pollution and Health,Jinan University,Guangzhou 511443,China

出　　处：《Journal of Environmental Sciences》2023年第8期52-64,共13页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.U1901220,41977343 and 42007365);Guangzhou Municipal Science and Technology Bureau(No.202103000046);Innovative Research Team of Department of Education of Guangdong Province(No.2020KCXTD005).

摘　　要：Environmental fate and ecological impacts of fipronil and its transformation products(FIPs)in aquatic environment have caused worldwide attention,however,the influence of dissolved organic carbon(DOC)on multimedia distribution,bioavailability,and toxicity of FIPs in field waterways was largely unknown.Here,we collected 11 companion water and sediment samples along a lotic stream in Guangzhou,South China.FIPs were ubiquitous with total water concentrations ranging from 1.22 to 43.2 ng/L(14.8±12.9 ng/L)and fipronil sulfone was predominant in both water and sediment.More than 70%of FIPs in aqueous phase were bound to DOC and the KDOC values of FIPs were approximately 1–2 orders of magnitude higher than K_(d-s)/K_(OC),emphasizing the significance of DOC in phase partitioning and transport of FIPs in aquatic environment.Water and sediment samples were more toxic to Chironomus dilutus than Hyallela azteca,and FIPs(especially fipronil sulfone)pronouncedly contributed toxicity to C.dilutus.Toxic units(TU)based on freely dissolved concentrations in water determined by solid phase microextraction significantly improved toxicity estimation of FIPs to the invertebrates compared to TUs based on aqueous concentrations.The present study highlights the significance of DOC association on fate and ecological risk of hydrophobic insecticides in lotic ecosystem.

关 键 词：Hydrophobic organic contaminant BIOAVAILABILITY Partitioning Aquatic toxicity Passive sampler 

分 类 号：X52[环境科学与工程—环境工程] X171.5