Bacteriological Contaminants of Some Fresh Vegetables Irrigated with Awetu River in Jimma Town, Southwestern Ethiopia

Abstract

The main purposes of this study were to determine the bacteriological load and safety of some fresh vegetables irrigated with Awetu River in Jimma town, southwestern Ethiopia. Water and vegetable samples were collected from three different irrigation sites and analyzed for their bacteriological contaminants following standard procedures. The maximum overall means of aerobic mesophilic bacteria, Enterobacteriaceae, aerobic spore formers, staphylococci, and total and fecal coliform counts were 8.06, 7.10, 6.54, and 2.97 log CFU g−1 and 1036 and 716 MPN 100 mL−1, respectively. The microflora of vegetable samples was dominated by Bacillus species (32.7%) followed by Enterobacteriaceae (25%) and Micrococcus (16%). Staphylococcus aureus and Salmonella spp. were detected in 24.0% and 20.7% of the samples, respectively. All the Staphylococcus aureus isolates were resistant to ampicillin, cefuroxime sodium, and penicillin G (100.0% each). All the Salmonella isolates were also resistant to tetracycline, erythromycin, cefuroxime sodium, and penicillin G (100.0% each). The findings reveal that the river water used for irrigation in this study is a possible preharvest source of contamination to fresh vegetables which potentially constitutes a health risk to consumers.