Shoppers who use reusable grocery bags and do not routinely wash them may be putting themselves at risk for food poisoning. Researchers who tested dozens of bags found half contaminated with coliform bacteria, suggesting raw-meat or uncooked-food contamination. Further, E. coli was found in another 12 percent of the bags, according to a study funded by the American Chemistry Council. The data were released in opposition to a California bill proposing to ban single-use plastic bags.
The presence of E. coli in the reusable bags may be caused by fecal-oral contamination due to inadequate hygienic practices that when mixed with food could lead to food-borne illnesses, says ACSH's Dr. Gilbert Ross. From wherever the bacteria may originate, reusable bags seem to be a good vector for contamination. We assume plastic bags are generally free of such contamination. This information should be taken into account before the California legislature renders a decision on plastic bags."
