Ecotoxicity and Bioaccumulation of Pharmaceuticals: Evaluation of Treatment in anaerobic Bioreactors

Abstract

When released into the environment, pharmaceuticals can cause toxic effects and are liable to bioaccumulate in different organisms even at low concentrations. Thus, these emerging contaminants need to be removed in effluent treatment plants and anaerobic reactors, which have already shown potential for degradation, especially in the acidogenic phase. In this context, the project presented seeks to evaluate the ecotoxicity and bioaccumulation of drugs before and after treatment by anaerobic bioreactors. Six drugs will be studied: atenolol, carbamazepine, diclofenac, ibuprofen, propranolol and triclosan. This research is part of the Project SABESP-FAPESP ATIVA-ETE (2020/09912-6). In the first stage, the removal of target compounds will be carried out in batch to treat synthetic sanitary sewage, with an anaerobic system operated with phase separation (acidogenesis and methanogenesis). In the second stage, samples before and after the anaerobic system will be evaluated for lethal and sublethal ecotoxicity effects with two bioindicator species, the microalgae Raphidocelis subcapitata and the cladoceran Ceriodaphnia silvestrii. In the third step, the bioaccumulation of the studied pharmaceuticals in the samples before and after the anaerobic treatment will be analyzed for the species R. subcapitata, C. silvestrii, in addition to the macrophyte Salvinia auriculata and the microcrustacean Hyalella meinerti. Therefore, the results can show the application of ecotoxicological tests to evaluate the treatment by anaerobic bioreactors. There is expected to be a reduction in ecotoxicity to bioindicator organisms with the pharmaceutical's removal. Furthermore, the risks of bioaccumulation of these target compounds may indicate effects that are not commonly observed with species representative of tropical environments.