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Functional diversity provides a new way for chemical risk assessment

TerraChem team members from the Institute of Environmental Sciences present a new method for chemical risk assessment that helps predict the effects of chemical pollution to ecosystems. Functional sensitivity distributions show ecotoxicological effects on loss of both diversity of species and diversity of ecological roles.

Chemical pollution is one of the biggest threats to biodiversity. Human-made chemicals like pesticides and herbicides can damage ecosystems, ultimately affecting humans by reducing crop yields or harming other ecosystem services. The effects of chemical exposure to biodiversity is usually estimated by sensitivity distributions, a well-established method in ecotoxicological assessments. However, this method does not consider the functional roles of species within ecosystems.

TerraChem team members from the Institute of Environmental Sciences (Leiden University) have presented a method to estimate the toxic effects of chemicals on functional diversity. This method uses the species sensitivity distribution, but with functional traits instead of species counts. The team used this functional sensitivity distribution to test the effects of the herbicide atrazine on plants of the order Poales (grasses and wheats) and the insecticide malathion on fish of the order Cypriniformes (carps). Both orders contain vital species for human food supply.

Their results show increasing negative effects on both functional and species richness in these groups with increasing chemical concentrations. This method can help regulators assess toxic effects of chemicals on ecosystems and can support decisions on risk management measures for chemicals already on the market.

Read the original scientific article, published in Environment International, here.