Pathogen and heavy metal contamination in urban agroecosystems of northern Ghana: Influence of biochar application and wastewater irrigation

The benefit of biochar as a soil fertility enhancer is well known and has been broadly investigated. Equally, many tropical subtropical countries use wastewater for irrigation in urban agriculture. To assess the related health risks, we determined pathogen heavy metal fate associated with application agriculture northern Ghana. Rice (Oryza L.) husk (20 t ha−1), N–P–K 15–15–15 fertilizer (212.5 kg their combinations were evaluated field-based experiment. Untreated tap water served water. Red amaranth (Amaranthus cruentus was used test crop grown wet (WS) dry (DS) cropping seasons. Irrigation water, soil, vegetables analyzed metals, Escherichia coli, fecal coliform, helminth eggs, Salmonella spp. Unlike pathogens, metals from below FAO/WHO permissible standard agricultural activities. Wastewater caused E. coli concentrations ranging 0.5 to 0.6 0.7 0.8 log10 colony forming units per gram fresh weight (CFU gFW−1) on 1.7 2.1 1.0 log10CFU (gDW−1) soil. Average gFW−1 rates 6.19 3.44 coliform found vegetables, whereas 4.26 4.58 gDW−1 observed WS DS, respectively. Helminth egg populations high transferred crops Biochar did not affect bacteria contamination. Pathogen contamination directly linked minimal or no difference application.