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The aim of the present study was to assess the ecotoxicity and genotoxicity of hospital laundry wastewaters generated from a regional hospital located in Rio Pardo Valley in the state of Rio Grande do Sul, Brazil. Physicochemical, microbiological, ecotoxicological, and genotoxic analyses were performed, and the results indicate that some parameters were not in accordance with the limit concentrations established by Brazilian and international guidelines for urban wastewaters. Daphnia magna (EC50 2.01%) and Danio rerio (LC50 29.25%) acute toxicity was detected, and sublethal effects were identified in Lactuca sativa (IC25 12.50%) and Allium cepa (IC25 51.25%). Cytotoxicity was observed at the five wastewater concentrations used yielding statistically significant differences (p < 0.05) in the meristematic cells of A. cepa compared with the negative control. The results obtained here warn about the necessity to develop treatment methods that can mitigate the environmental impacts caused by the ecotoxicity and genotoxicity of hospital laundry wastewaters.

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In the present study, treatment tests were performed on effluents generated from a hospital laundry using electrooxidation (EO) processes. Global parameter analyses and toxicological analyses were conducted before and after each trial. The analytical characterization of the effluent fractions from the hospital laundry revealed variable toxicities ranging from slightly toxic for the composite sample and extremely toxic for the Wash stage. Another parameter related to refractoriness at different currents involved measuring the chemical oxygen demand/biochemical oxygen demand (COD/BOD5) ratio, and a maximum ratio of 34.72 was observed in effluents from the wash stage. Ozonation, EO processes with iron electrodes alone, and combined with ozonation (EO/O3 and EO + O3) were used for the treatment tests. The tests involving the EO process for 60 min with induced conductivity through the addition of NaCl exhibited the best performance. Considering the best performance in previous assays, only the electrochemical methods were evaluated with the toxicological analyses. The application of the three‐electrochemical methods provided detoxification levels that improved to moderately or slightly toxic. In one of the conditions, the effluent generated in the initial rinse of the linens improved from the condition of extremely toxic (12.58%) to moderately toxic (61.59%), while the COD decreased by 9%. With respect to the effluent coming from the wash step, the COD showed a 41% reduction, while the toxicity was reduced considerably from the condition of extremely toxic (6.89%) to slightly toxic (76.65%).

Monitoring of triphenyltin (TPhT) in the environment, particularly to control its misuse in agriculture, is of great importance because of its high toxicity.

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