Reusable grocery bags can be a breeding ground for dangerous food-borne bacteria and pose a serious risk to public health, according to a joint food-safety research report issued by the University of Arizona (UA) and Loma Linda University in California.
The research study – which randomly tested reusable grocery bags carried by shoppers in Tucson, Los Angeles, and San Francisco – also found consumers were almost completely unaware of the need to regularly wash the bags.
"Our findings suggest a serious threat to public health, especially from coliform bacteria including E. coli, which were detected in half of the bags sampled," said Charles Gerba, a UA soil, water, and environmental science professor and co-author of the study.
"Furthermore, consumers are alarmingly unaware of these risks and the critical need to sanitize their bags on a weekly basis," Gerba said.
Bacteria levels found in reusable bags were significant enough to cause a wide range of serious health problems and even death. The levels are a particular danger for young children who are especially vulnerable to food-borne illnesses, Gerba says.
The study also found that awareness of potential risks was very low. Ninety-seven percent of those interviewed never washed or bleached the reusable bags, says Gerba, adding that thorough washing kills nearly all bacteria that accumulate in the reusable bags.