Fate of the fecal indicator Escherichia coli in irrigation with partially treated wastewater

摘要: Treated wastewater reuse is increasing in semi-arid regions as a response to the effects of climate change and increased competition for natural water resources. Investigating fate bacterial indicators relevant assess their persistence environment possible transfer groundwater or food chain. A long-term field-scale experimental campaign soil column test were carried out evaluate fecal indicator Escherichia coli (E. coli) cultivated when contaminated resources are used irrigation. For field experiments, contamination was simulated by dosing effluent membrane bioreactor, thus simulating filtration system's failure, irrigating where grass grown. The presence E. on topsoil samples monitored under different scenarios. evaluating same subsoil, set columns installed next field, operated, concentration over time along depth. Real municipal this case source contamination. Results showed that short- medium-term strongly dependent irrigation water. Limited no accumulation observed. Watering events performed after did not influence significantly decay topsoil, which followed log-linear model. trend concentrations leaching model well, suggesting dominant mechanism affecting underground indicator's concentration.