Zhang Yan, Wang Xiaozhuang, Zhao Wanli, Liu Yucan, Liu Tongshuai, Yang Peiyuan
College of Civil Engineering, Yantai University, Yantai 264000, China.
Logistics Division, Zibo Vocational Institute, Zibo 255000, China.
Toxics. 2023 Feb 26;11(3):222. doi: 10.3390/toxics11030222.
The effect of malathion in ice is a poorly researched area, and ice is an important habitat for organisms at the base of the food web. This study presents laboratory-controlled experiments designed to investigate the migration rule of malathion during lake freezing. Concentrations of malathion were determined in samples of melted ice and in under-ice water. The effects of the initial sample concentration, freezing ratio, and freezing temperature on the distribution of malathion in the ice-water system were investigated. The concentration effect and migration capacity of malathion during freezing was characterized by the concentration rate and distribution coefficient. The results showed that the formation of ice led to the concentration of malathion appearing as follows: concentration in under-ice water > concentration in raw water > concentration in ice. This implied that malathion tended to migrate from the ice to the under-ice water during the freezing process. The increase in the initial malathion concentration, freezing ratio, and freezing temperature caused a more pronounced repulsion of the malathion by the ice and increased the migration to the under-ice water. When the solution of malathion with an initial concentration of 50 μg/L was frozen at -9 °C and the freezing ratio reached 60%, the concentration of malathion in the under-ice water was concentrated to 2.34 times the initial concentration. The migration of malathion to under-ice water during freezing may pose a potential threat to under-ice ecology; therefore, the environmental quality and impact of under-ice water in icebound lakes needs to be given more attention.
马拉硫磷在冰中的效应是一个研究较少的领域，而冰是食物网底层生物的重要栖息地。本研究开展了实验室对照实验，旨在探究湖泊结冰期间马拉硫磷的迁移规律。测定了融冰样本和冰下水体中马拉硫磷的浓度。研究了初始样本浓度、结冰率和结冰温度对马拉硫磷在冰水系统中分布的影响。用浓缩率和分配系数表征了结冰过程中马拉硫磷的浓缩效应和迁移能力。结果表明，结冰导致马拉硫磷的浓度呈现如下情况：冰下水体中的浓度＞原水中的浓度＞冰中的浓度。这意味着在结冰过程中马拉硫磷倾向于从冰迁移至冰下水体。初始马拉硫磷浓度、结冰率和结冰温度的增加导致冰对马拉硫磷的排斥作用更明显，并增加了向冰下水体的迁移。当初始浓度为50 μg/L的马拉硫磷溶液在-9℃冷冻且结冰率达到60%时，冰下水体中马拉硫磷的浓度浓缩至初始浓度的2.34倍。结冰期间马拉硫磷向冰下水体的迁移可能对冰下生态构成潜在威胁；因此，冰封湖泊中冰下水体的环境质量和影响需要得到更多关注。
