Avaliação da ecotoxicidade da losartana potássica em Daphnia magna e Desmodesmus subspicatus

Abstract

Antihypertensive drugs are among the most commonly drugs found in nature, and the main entry routes of these pharmacological residues into the environment are through the excretion of patients and inappropriate disposal in sewage systems. The interest about knowing the effects that these substances may have on ecologically relevant aquatic organisms increases gradually. Losartan potassium is the main agent of this class of drugs, being the most consumed drug in Brazil in recent years and found in water bodies at concentrations ranging from ng L-1 to μg L-1. The objective of this study was to evaluate the effects of losartan potassium in aquatic organisms of two different trophic levels, using chronic bioassays with Desmodesmus subspicatus, according to ABNT NBR 12648:2011, and acute bioassays with Daphnia magna, according to ABNT NBR 12713:2016. It was also evaluated the genotoxic potential of this compound in Daphnia magna through the comet assay. In the bioassay with Desmodesmus subspicatus, the LOEC50 value was 27.9308 ± 0.0751 mg L-1. For Daphnia magna, the EC50 value was 303.69 ± 16.38 mg L-1, thus observing greater sensitivity of the organism Desmodesmus subspicatus. In relation to the compound genotoxicity, it was possible to determine significant DNA damage for the studied concentrations. With the performed bioassays, it was obtained data that helped to understand the effects of this drug in organisms of natural aquatic environments, showing the toxicity to the test organisms used and highlighting the importance of studies investigating adverse effects of chemical substances in natural environments.