Effects of nonionic surfactants on life history traits of Drosophila melanogaster

Surfactants are used for a variety of applications such as emulsifiers, solubilizers, or foaming agents. Their intensive production and use in pharmaceutical, cosmetic and agricultural products have resulted in their continuous discharge in the environment, especially via wastewaters. Surfactants have become a threat to living organisms as they interact with, and disrupt, cell membranes and macromolecules. Their effects have mainly been studied in aquatic species; however, terrestrial organisms are also threatened by these emerging contaminants. This study investigates the effects of two widely used nonionic surfactants, Tween-20 and Triton X-100, on key traits of larvae and adults of the fruit fly Drosophila melanogaster. We assessed the toxicity of the two surfactants on viability, development time, body size and food intake of the flies. The results revealed that both surfactants induced toxic effects on the drosophila flies leading to decreased viability, delayed development and lowered food consumption at the highest tested concentrations. Both surfactants proved to be toxic to flies, and, for all tested traits, Triton X-100 appeared more toxic than Tween-20. Our results might extend to other invertebrates. The widespread use of these substances, which then end up in the environment, should be regulated to mitigate their impacts on biodiversity and ecosystems.