Journal Article

Occurrence and risk assessment of microcystin and its relationship with environmental factors in lakes of the eastern plain ecoregion, China

Steinman, Alan D., Shu, Xiubo, Gu, Yurong, Xue, Qingju, Zhu, Guangwei, Zou, Wei, Wan, Xiang, Xie, Liqiang

2020

Overview

The frequent occurrence of microcystins (MCs) in freshwater poses serious threats to the drinking water safety and health of human beings. Although MCs have been detected in individual fresh waters in China, little is known about their occurrence over a large geographic scale. An investigation of 30 subtropical lakes in eastern China was performed during summer 2018 to determine the MCs concentrations in water and their possible risk via direct water consumption to humans, and to assess the associated environmental factors. MCs were detected in 28 of 30 lakes, and the highest mean MCs concentrations occurred in Lake Chaohu (26.7 μg/L), followed by Lake Taihu (3.11 μg/L). MC-LR was the primary variant observed in our study, and MCs were mainly produced by Microcystis , Anabaena ( Dolicospermum ), and Oscillatoria in these lakes. Replete nitrogen and phosphorus concentrations, irradiance, and stable water column conditions were critical for dominance of MC-producing cyanobacteria and high MCs production in our study. Hazard quotients indicated that human health risk of MCs in most lakes was at moderate or low levels except Lakes Chaohu and Taihu. Nutrient control management is recommended to decrease the likelihood of high MCs production. Finally, we recommend the regional scale thresholds of total nitrogen and total phosphorus concentrations of 1.19 mg/L and 7.14 × 10 −2  mg/L, respectively, based on the drinking water guideline of MC-LR (1 μg/L) recommended by World Health Organization. These targets for nutrient control will aid water quality managers to reduce human health risks created by exposure to MCs.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Anabaena / Aquatic Pollution / Atmospheric Protection/Air Quality Control/Air Pollution / China / Cyanobacteria / Drinking water / Earth and Environmental Science / ecoregions / Ecotoxicology / Environment / Environmental Chemistry / Environmental factors / Environmental Health / Environmental science / freshwater / guidelines / Health hazards / Health risks / human health / humans / Irradiance / Lakes / light intensity / Microcystins / Microcystis / Nitrogen / Nutrients / Oscillatoria / Phosphorus / Quotients / Research Article / risk / Risk assessment / summer / total nitrogen / total phosphorus / Waste Water Technology / Water circulation / Water column / Water consumption / Water Management / Water Pollution Control / Water quality / Water quality control / Water quality management / World Health Organization