Evaluation of DEET cytotoxicity on Perna perna mussels

Abstract

Recent studies have identified the presence of several emerging pollutants in aquatic environments. The occurrence in different environmental matrices has been continuously reported, highlighting the need for toxicity studies. Developed in the 1940s and present in many commercially available formulations, the DEET (N,N-diethyl-meta-toluamide) is the active agent used in most insect repellents. Several studies have been identified the DEET presence in surface water and in wastewater treatment plant (WWTP) effluent, so this compound is considered an emerging pollutant and studies indicate that DEET is only slightly toxic to aquatic organisms. Even nowadays the environmental destiny of DEET is not completely understood. Although DEET is considered a compound resistant to degradation and commonly found in surface water, there are not complete assessments for ecological risk of DEET, including studies evaluating chronic toxicity to aquatic organisms. In this study was evaluated the DEET toxicity and the effects caused in lysosomes of Perna perna mussels hemocytes. For this purpose, firstly was performed the acute toxicity assay to identify the DEET concentration that causes 50% mortality of exposed organisms to DEET concentrations in the range of 75 to 400 mg L-1 and the obtained lethal dose (LC50) was 114.27 mg L-1. To assess the stability of the lysosomal membrane in organisms exposed to this compound was carried out the cytotoxicity assay utilizing DEET concentrations in a range of 0.001 to 1.0 mg L-1. In fact, is important reinforce that the data of DEET cytotoxicity showed disturbances in Perna perna mussels in all tested concentrations.