Pathogens and pharmaceuticals in source-separated urine in eThekwini, South Africa. (15th November 2015)

• Record Type: Journal Article
• Authors: Bischel, Heather N.; Özel Duygan, Birge D.; Strande, Linda; McArdell, Christa S.; Udert, Kai M.; Kohn, Tamar
• Is Part Of: Water research. Volume 85(2015)
• Page Start: 57
• Page End: 65
• Publication Date: 2015-11-15
• Subjects: Urine nutrient recovery -- Health hazards -- Risk -- Sustainable sanitation; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2015.08.022
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: In eThekwini, South Africa, the production of agricultural fertilizers from human urine collected from urine-diverting dry toilets is being evaluated at a municipality scale as a way to help finance a decentralized, dry sanitation system. The present study aimed to assess a range of human and environmental health hazards in source-separated urine, which was presumed to be contaminated with feces, by evaluating the presence of human pathogens, pharmaceuticals, and an antibiotic resistance gene. Composite urine samples from households enrolled in a urine collection trial were obtained from urine storage tanks installed in three regions of eThekwini. Polymerase chain reaction (PCR) assays targeted 9 viral and 10 bacterial human pathogens transmitted by the fecal–oral route. The most frequently detected viral pathogens were JC polyomavirus, rotavirus, and human adenovirus in 100%, 34% and 31% of samples, respectively. Aeromonas spp. and Shigella spp. were frequently detected gram negative bacteria, in 94% and 61% of samples, respectively. The gram positive bacterium, Clostridium perfringens, which is known to survive for extended times in urine, was found in 72% of samples. A screening of 41 trace organic compounds in the urine facilitated selection of 12 priority pharmaceuticals for further evaluation. The antibiotics sulfamethoxazole and trimethoprim, which are frequently prescribed as prophylaxis for HIV-positive patients, were detected in 95% and 85% of samples, reaching maximum concentrations of 6800 μg/L and 1280 μg/L, respectively. The antiretroviral drug emtricitabine was also detected in 40% of urine samples. A sulfonamide antibiotic resistance gene ( sul1 ) was detected in 100% of urine samples. By coupling analysis of pathogens and pharmaceuticals in geographically dispersed samples in eThekwini, this study reveals a range of human and environmental health hazards in urine intended for fertilizer production. Collection of urine offers the benefit of sequestering contaminants from environmental release and allows for targeted treatment of potential health hazards prior to agricultural application. The efficacy of pathogen and pharmaceutical inactivation, transformation or removal during urine nutrient recovery processes is thus briefly reviewed. Graphical abstract: Highlights: Human and environmental health hazards of source-separated urine were assessed. Analysis included 19 pathogens, 12 pharmaceuticals and 1 antibiotic resistance gene. Up to 6 pathogens and 10 pharmaceuticals were detected within a single sample. A sulfonamide resistance gene ( sul1 ) was detected in 100% of urine samples tested. Urine treatment to produce fertilizers can reduce these health hazards.