Quantification of Waterborne Pathogens and Associated Health Risks in Urban Water

Citizens are exposed to microbial hazards in urban waters. To quantify health risks associated with this exposure, pathogen concentrations in an urban river, lake, rainwater sedimentation pond, a pond in a park, and a wadi, were assessed. E. coli concentrations were variable in all locations, with mean values ranging between 1.2 × 102 (lake) and 1.7 × 104 (sedimentation pond) cfu (colony forming units)/100 mL. High concentrations of Campylobacter were found, being the lowest in the lake (4.2 × 101 gc (genomic copies)/L) and the highest in the wadi (1.7 × 104 gc/L). Cryptosporidium was not found in any sample. Low levels of adenovirus 40/41 were found in some samples in the river (1.8 × 101 gc/L) and lake (7.2 × 10° gc/L), indicating human fecal contamination. Legionella pneumophila was found in the sedimentation pond, with higher concentrations after rain events (1.3 × 102 gc/L). Cyanochlorophyll-a was found in the lake (7.0 × 10–1 μg/L), the sedimentation pond (1.1 × 10° μg/L), and the pond in the park (...