Environmental behavior of methamphetamine and ketamine in aquatic ecosystem: Degradation, bioaccumulation, distribution, and associated shift in toxicity and bacterial community. (1st May 2020)

• Record Type: Journal Article
• Authors: Wang, Zhenglu; Han, Sheng; Cai, Min; Du, Peng; Zhang, Zhaobin; Li, Xiqing
• Is Part Of: Water research. Volume 174(2020)
• Publication Date: 2020-05-01
• Subjects: Psychoactive drugs -- Lab-scale ecosystem -- Environmental fate -- Ecological implications; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2020.115585
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: Ketamine (KET) and methamphetamine (METH) have been recognized as emerging contaminants in aquatic ecosystems. This paper aimed to investigate the environmental behaviour, including the degradation, distribution, and bioaccumulation, of METH, KET, and their main metabolites (amphetamine (AMP) and norketamine (NorKET)). The changes in acute toxicity in the aqueous phase and in the bacterial community in sediment were determined to assess the associated eco-risk of the drug exposure. Five types of lab-scale aquatic ecosystems were established and exposed to KET or METH for 40 days: a water- sediment- organisms- KET system (K), a water- sediment- organisms- METH system (M), a water- sediment- organism- METH- KET system (M + K), a water-sediment- KET- METH system (control), and a water- sediment- organisms system (biocontrol). The results demonstrated that much faster degradation occurred for both METH (t1/2 = 3.89 and 2.37 days in the M and M + K group, respectively) and KET(t1/2 = 5.69 days 5.39 days in the K group and M + K group, respectively) than in the control group (t1/2 = 7.83 and 86.71days for METH and KET, respectively). Rapid adsorption of KET, METH, and their metabolites was observed in the sediment, which had clay and silt as the main particle sizes. KET was observed to be absorbed by shallow-water fish (Chinese medaka, rosy bitterling and mosquito fish), while METH was dominantly ingested by bottom-dwellers (loach). Duckweed might play a crucial role in the dissipation process of METH and KET, which were mainly adsorbed by duckweed roots. During incubation, the acute toxic levels in the K and M + K groups changed from non-toxic to medium toxicity levels, and the toxicity in the M and control groups changed from non-toxic to low toxicity levels. Moreover, marked changes in the bacterial community in the sediment induced by METH or KET exposure were observed, and the most significant change in the bacterial community was observed in the group spiked with both METH and KET. This work for the first time elucidated the environmental behaviors of METH and KET in aquatic ecosystem and associated the impact on ecological system equilibrium. Graphical abstract: Image 1 Highlights: Bioaccumulation and distribution of methamphetamine and ketamine in varying mediums took place. Accumulation of methamphetamine and ketamine in fish was correlated to lipid or protein contents. Degradation of methamphetamine and ketamine was accelerated by aquatic creatures. The significant increase of water toxicity level was observed in experiment groups. The combine of methamphetamine and ketamine induced marked shift in sediment bacterial community.