Microbial Contamination of Grocery Shopping Trolleys and Baskets in West Texas

The objective of this study was to identify food safety risk factors associated with supermarket trolleys (grills and handles) and handheld baskets. Indicator microorganisms evaluated were those detected by aerobic plate count (APC), yeast and molds (YM), Enterobacteriaceae (EB), environmental Listeria (EL), coliforms (CF), and E. coli (EC). In addition, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157 and Salmonella sp. were tested for. Trolley grills (n = 36) had EB counts of 2.4 × 102 CFU/cm2. Trolleyhandles (n = 36) had 2.7 × 106 of CF and 5.2 CFU/cm2 of YM. The bottom of handheld baskets (n = 25) had 3.5 × 105 CFU/cm2 of CF and 5.07 CFU/cm2 of EC. S. aureus was found on 96% of the baskets, 50% of the trolley handles (18 out of 36 samples), and 42% of the trolleys’ grills. E. coli O157 was identified on 17% of baskets, 3% on trolley grills, and 3% on handles. Salmonella sp. was detected on 16% of baskets and 8% of trolley grills. L. monocytogenes was detected on 17% of the bottoms of handheld baskets but on none of the other samples. These results suggest the need for implementation of sanitation programs to regularly clean trolleys and baskets, as well as for consumer education.