Freshwater gastropods as a tool for ecotoxicology assessments in Latin America

摘要

Despite the mollusks being the second largest group in Kingdom Animalia, they have not been considered in environmental risk assessment so far, mainly due to the lack of standardized protocols. In this sense, the gastropods, with abundant species widely distributed in aquatic environments, have been employed in water and sediment quality assessments due their clear sensitivity to chemical compounds, as pollution indicators for different substances. Acute and chronic toxicity tests have been mostly used in ecotoxicological protocols to evaluate potential effects of contaminants on natural populations. However, with the need to assess potential sublethal hazards to ecosystems of pollutants at low concentrations, environmental monitoring programs have encouraged analyzing effects on gametes, fertilization, reproduction and embryo-larval development. Furthermore, among the myriad of chemicals reaching the environment, some compounds can directly affect the reproductive potential through induction of mutations in germ cells and vulnerable embryos. This work discusses some case studies of standardization assays with freshwater snails, especially good organisms for laboratory and in situ monitoring studies, to be considered for regulatory environmental agencies. In that context, this work also shows the prospects for using gastropods in monitoring freshwater environments in Latin America.