Purpose: Microbial and heavy metal contamination associated with street food business in Kampala, Jinja and Masaka districts was assessed.
Methods: Standard microbiological methods were used to determine coliforms, S. aureus, E. coli, B. cereus, Campylobacter spp., Pseudomonas spp., and Salmonella spp.counts. Selected street foods, use-water, food vendor’s hands, utensils, final dish rinse-water and serving surfaces were tested. Heavy metal (Cadmium, Lead, Zinc, Copper and Nickel) levels were determined using Atomic Absorption Spectrophotometer. Swabbing method was used to determine surface contaminations. A total of 60 samples were tested
Results: S. aureus, coliforms and E. coli ranged between <1 and 6.18 ± 0.24 log CFU/g (cm2, ml). S. aureus counts were significantly different (P < 0.05) amongst street foods. S. aureus, coliforms, E. coli, B. cereus, Campylobacter spp., and Pseudomonas spp in use-water were <1 log CFU/ml. Coliforms and S. aureus counts on serving surfaces, vendors’ hands and serving utensils, use-water and final dish rinse-water ranged between < 1 to 4.22 ± 1.81 log CFU/cm2 (ml). No significant difference (P > 0.05) in E. coli counts detected on serving surfaces and utensils. Bacillus cereus, Campylobacter spp. and Pseudomonas spp. were <1 log CFU/g (ml). Heavy metal levels varied from 0.01 to 9.4 ppm. In all the districts, bean and groundnut sauce had the highest cadmium concentrations. Bean sauce and chapatti samples had significantly different (P < 0.05) Copper levels among the districts. Nickel was undetectable. Use-water collected from Kampala district had highest Cadmium (0.36 ppm), Zinc (1.68 ppm) Lead (7.6ppm) and Copper (2.08ppm).
Significance: Some of the street foods and surfaces constituted a health risk due high microbial numbers and heavy metal levels. There is need for conducting a risk assessment and sensitization of vendors on basic food safety practices and behavioral change.