Aquatic Microcosms in Ecotoxicology: The Community-Level Ecological Risk Assessment of Pollutants

Microcosm technology serves as a sophisticated tool for simulating natural ecosystems, facilitating the examination of pollutants' ecological impacts across population, community, and ecosystem scales. Currently, this technology finds extensive application in ecological toxicology and ecological risk assessment research. This concise review highlights the utility of microcosm technology in ecotoxicology, detailing the establishment of aquatic microcosms and analyzing key research trends to assess the ecological impacts of pollutants. It emphasizes the evaluation of pesticides, industrial chemicals, and heavy metals, providing a comparative analysis of safety thresholds derived from microcosm studies versus other methods. Finally, the review underscores the four urgent directions for future exploration: (a) track pollutant metabolites in microcosms; (b) develop microcosms with diverse species for natural ecosystem mimicry; (c) use DNA macrobarcoding to assess zooplankton and link it to species abundance; (d) study reasons behind no observed effect concentration (NOEC) vs. the 95% harmless concentration (HC5) values in microcosm studies. The determination of these directions helps to fill the gaps in understanding the fate and effects of pollutants within controlled ecosystem simulations.