Applying sunscreens on earthworms: Molecular response of Eisenia fetida after direct contact with an organic UV filter

The use of organic Ultraviolet (UV)filters has increased in the last years, either in sunscreens, other cosmetics, oreven food packaging. Thesefilters may end up in soil and water since the Wastewater Treatment Plants may notsuccessfully remove them. Among them, benzophenones are known to act as endocrine disruptors. However,most of the studies are directed towards vertebrates and aquatic invertebrates, while there is a lack of informa-tion on the molecular mechanisms affected by these compounds on soil dwelling invertebrates. Here, we studythe impact of direct acute (48 h) contact of 4-hydroxybenzophenone (4-OHBP) at two sublethal concentrations(0.02 and 0.2 mg/mL) on gene expression of the earthwormEisenia fetida. Investigated genes were involved inendocrine pathways, stress response, detoxification mechanisms, genotoxicity, energy metabolism and epige-netics. Three of them were identified for thefirst time in earthworms. Our results suggest that exposure to 4-OHBP affected endocrine pathways, causing an increase in the Ecdysone receptor gene (EcR) expression. More-over, the UVfilter induced changes in the CuZn superoxide dismutase gene (CuZn SOD), indicating an effect inthe stress response. Finally, significant changes were detected for glyceraldehyde-3-phosphate dehydrogenasegene (GAPDH) expression, indicating that energy metabolism is influenced by the 4-OHBP and highlighting therisks of usingGAPDHas an internal reference for Real Time PCR