Occurrence of pathogens on vegetables harvested from soils irrigated with contaminated streams

The study assesses the contamination level, the seasonal distribution and the toxigenicity of pathogens isolated from irrigated vegetables and the water used for irrigation. A total of 196 samples of water used for irrigation and 326 irrigated vegetables were obtained from Kawo drain, Sabon Gari drain and River Galma and examined using standard procedures for coliform and viable counts and the presence of E. coli, Salmonella and Vibrio during the dry and wet seasons. Irrigation water from Kawo drain had significantly higher coliform counts by location and season than water from the other two locations. Although all the vegetables had coliform counts higher than the recommended standard (range 3.40–6.38 log10 cfuml−1), amaranthus had significantly higher (P<0.05) counts than other vegetables during the dry season. Salmonella was significantly more likely to be detected during the dry season than during the wet (OR 4.91, 1.07