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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.

The development of integrated systems for wastewater treatment has been investigated in recent years not only for the improvement of control parameters but also to allow the routine reuse of wastewater to be effectively implemented. Several studies also seek to add processes that may reuse by-products, energy, and unit operations in a single integrated remediation unit. Considering the sustainability scenario, all these processes should be designed and controlled with description of scope, mass inventory, and energy demand in order to establish indexes of environmental pressure. Classical publications of books and articles for wastewater treatment have already described to more than 10 years several procedures and standards for reuse (direct or indirect), segregation at source, required treatment levels, groundwater recharge, combination of remediation processes, logistics, and sanitation. In this case, further investigation to decentralized systems, such as reed bed filters, with reduced costs of implementation and operation is required, as well as the simplicity of units to be installed. This tendency of integrated phytoremediation systems supports the growing interest for the combination of a system already considered classic in wastewater treatment, the constructed wetlands (CWs), with advanced oxidation processes (AOPs), particularly the photocatalysis with direct or indirect use of solar energy. Because of its already reported disinfection and detoxification potentials which might enable the reuse of urban wastewaters for some specific purposes, the photocatalytic treatment was selected for a study of case. So, this chapter covers the phenological aspects of a macrophyte still little used in phytoremediation, the Hymenachne grumosa; the evolution of the combined use of Upflow Anaerobic Sludge Blanket systems (UASB) + CWs; and the integration of the processes UASB + CWs + UV /TiO 2 /O 3 with indirect use of solar energy in photoreactors designed for these studies.

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