In this study, the microbial quality of treated wastewater used for irrigation of three public parks in Dubai was evaluated. A total of 23 samples of TWW （treated wastewater） and 12 samples of irrigated soils from t...In this study, the microbial quality of treated wastewater used for irrigation of three public parks in Dubai was evaluated. A total of 23 samples of TWW （treated wastewater） and 12 samples of irrigated soils from three public parks were collected and tested for Legionella, Salmonella, traditional bacterial indicators, Cryptosporidium oocyst and Giardia cysts using membrane filtration and direct immune-fluorescence assay. The majority of the tested water samples were found contaminated with LLO （Legionella like organisms）, Salmonella and traditional bacterial indicators. Both Cryptosporidium oocysts and Giardia cysts were detected in these samples with a higher occurrence ofCryptosporidium oocysts （96%） than Giardia cysts （35%）. The fecal coliform bacteria were detected in 60.8% of water samples and 58% of soil samples. Total coliform bacteria were detected in most of the water and soil samples with a higher occurrence than the fecal coliform bacteria. The results of this study indicate that microorganisms are surviving the chlorination method used for disinfecting wastewater, and are further multiplying in the public parks irrigation network system. Therefore, monitoring the treated wastewater for bacterial pathogens, protozoan parasites and controlling their growth at the point of end use are vital to reducing the risk of environmental contamination with microbial pathogens.展开更多
文摘In this study, the microbial quality of treated wastewater used for irrigation of three public parks in Dubai was evaluated. A total of 23 samples of TWW （treated wastewater） and 12 samples of irrigated soils from three public parks were collected and tested for Legionella, Salmonella, traditional bacterial indicators, Cryptosporidium oocyst and Giardia cysts using membrane filtration and direct immune-fluorescence assay. The majority of the tested water samples were found contaminated with LLO （Legionella like organisms）, Salmonella and traditional bacterial indicators. Both Cryptosporidium oocysts and Giardia cysts were detected in these samples with a higher occurrence ofCryptosporidium oocysts （96%） than Giardia cysts （35%）. The fecal coliform bacteria were detected in 60.8% of water samples and 58% of soil samples. Total coliform bacteria were detected in most of the water and soil samples with a higher occurrence than the fecal coliform bacteria. The results of this study indicate that microorganisms are surviving the chlorination method used for disinfecting wastewater, and are further multiplying in the public parks irrigation network system. Therefore, monitoring the treated wastewater for bacterial pathogens, protozoan parasites and controlling their growth at the point of end use are vital to reducing the risk of environmental contamination with microbial pathogens.
