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Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Behavior of metals, pathogen parasites, and indicator bacteria in sewage effluents during biological treatment by
K A A Tonani1, F C Julião, T M B Trevilato
1Laboratory of Ecotoxicology and Environmental Parasitology, Maternal Infant Nursing and Public Health Department, Ribeirão Preto College of Nursing, University of Sao Paulo, Av. Bandeirantes 3900, 14040-902, Ribeirão Preto, Sao Paulo, Brazil.
Abstract:
The purpose of this study was to evaluate the behavior of metals, pathogen parasites, and indicator bacteria in sewage effluents during biological treatment by activated sludge in a wastewater treatment plant in Ribeirão Preto (WTP-RP), Sao Paulo, Brazil. The evaluation was done during a period of 1 year. Results showed that metal concentrations in treated effluents decreased, reaching concentrations according to those established by national regulations. The activated sludge process at the WTP-RP promoted a partial removal of parasites considered as possible indicators according to the WHO guidelines. Reduction factors varied between 18.2% and 100% for agents such as Endolimax nana, Entamoeba coli, Entamoeba hystolitica, Giardia sp., Ancylostoma sp., Ascaris sp., Fasciola hepatica, and Strongyloides stercoralis. A removal was also observed in total and fecal coliforms quantification. The present study represents an initial evaluation of the chemical and microbiological removal capacity of the WTP-RP. The results should be of interest for the authorities responsible for the environmental health at municipal, regional, national, and international levels.
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