Ecotoxicological impact of removing pharmaceutical residues from aqueous solutions using recycled ultrafiltration...

The treatment of effluents containing pharmaceutical residues is a challenge, as these compounds require more robust and effective treatment for efficient removal. Thus, studies on the efficacy of ultrafiltration membranes using bioassays are fundamental to assess the long-term environmental impacts generated by new technologies. This study evaluated the efficiency of recycled ultrafiltration membranes modified with titanium dioxide (TiO₂) and graphene oxide (GO) in the removal of pharmaceutical compounds containing betamethasone, ketoprofen, fenofibrate, fluconazole, loratadine, and prednisone. Different sample components (feed, concentrate, and permeate) were subjected to ecotoxicity assessment bioassays using the organisms Aliivibrio fischeri and Allium cepa. The results of the tests conducted with the bacterium demonstrated that all tested membranes were effective in the treatment, as no toxicity was observed in the permeate samples for the evaluated membranes. Regarding the bioassays with A. cepa, there was no toxicity to germination and early growth for the tested samples, but biochemical and physiological alterations were observed in the seedlings. The concentrate samples from the three membranes induced higher stress in the plants, which was evidenced by increased lipid peroxidation (LP) and greater activity of the superoxide dismutase (SOD) enzyme. Higher frequencies of clastogenic and aneugenic abnormalities were also observed in the meristematic cells for the permeate samples from the third recycled membrane modified with TiO₂, graphene oxide, and photocatalysis. The effectiveness of the ultrafiltration membranes in eliminating toxic substances was confirmed by the ecotoxicological tests performed in this study.