Germs and reusable bags

Chico’s ordinance prohibiting grocery stores from distributing single-use plastic bags drew vocal protests when the City Council deliberated the measure last spring, and the opposition has found a second wind since the measure took effect Jan. 1.

On top of economic arguments, some critics cite health concerns associated with reusable bags, pointing to a research study on microbial contamination. That report, released in 2010 by scientists at the University of Arizona and Loma Linda University, determined that “reusable bags are seldom if ever washed and often used for multiple purposes. Large number of bacteria were found in almost all bags and … [w]hen meat juices were added to the bags and stored in the trunks of cars for two hours the number of bacteria increased tenfold.”

So, exactly how worried should we be? Are we harboring food-borne-illness factories with our earth-friendly totes?

Maybe so, likely not. The Butte County Department of Public Health says there are reasons to take precautions but shoppers who take those precautions needn’t be alarmed.

“There are health risks associated with reusable shopping bags, particularly when raw meat and poultry mix with raw foods,” said Dr. Mark Lundberg, the county’s public health officer. “Raw meat juices can drip on raw foods that may be eaten without further cooking, causing cross-contamination. This type of contamination can lead to bacterial food-borne infections such as campylobacter, E. coli, listeria, salmonella or staphylococcus.

“With the new plastic bag ban, consumers will need to be more diligent when adding raw meats and raw foods to the same bag.”

Lisa Almaguer, communications manager for Public Health, calls this practice “conscious shopping.” As she explained: “Before reusable bags, we would tend to go on auto-pilot through the store, throwing items into our cart. I believe when consumers are shopping, for groceries in particular, they need to be more conscious or aware of the food items they place in their reusable bags and how they mingle.”

Dr. Ryan Sinclair, an assistant professor at the Loma Linda School of Public Health who co-authored the research paper, agrees that the prospect of contamination from reusable bags should concern only those consumers who don’t clean them.

“The reusable grocery bag is just one more thing that will transmit infectious disease on top of all the other things that will transmit infectious disease,” Sinclair said. “We hear about epidemics, and [people respond], ‘Oh, I’m not going to get Norovirus from my reusable grocery bag!’

“Well, maybe not, but you never know where you next cold or flu comes from; you never know where you’ll get your next stomach issue or something that resembles food poisoning.”

Sinclair’s latest research includes evaluating antimicrobial materials that could compose the next generation of reusable bags, and he recently finalized the contamination study from five years ago. He and his associates tested a variety of bags: primarily cloth and textured-plastic totes, but also a few thicker-gauge plastic bags that have become more common. In all cases, he said, bags proved a conveyance for bacteria.

Roplast, the Oroville-based manufacturer of reusable plastic bags whose client list includes many Chico stores, says its products differ from what Sinclair, et al, tested. Those bags, said Lisa Mendonca, Rosplast’s grocery sales manager, “are generally dark in color and the fabric is very porous. We believe this makes spills and dirt hard to see and it allows it to soak in and dry unnoticed. These types of bags are also very hard to clean and often get ruined when trying to wash.

“Our bags are slick, nonporous material that does not allow spills to soak in. Most of our bags are white or light in color, making it easy to see dirt and spilled foods. This should make noticing that your bag is dirty much easier and prompt you to wash.”

Regardless of the composition, cleanliness is key.

Roplast offers basic hand-wash instructions: put a little dish soap inside, swirl around, use a sponge if desired, rinse out with warm water, hang upside-down on the drainboard to dry.

Sinclair recommends putting all bags in the washing machine, and if they break apart, just replace them. (Mendonca says Roplast bags hold up in washing machines and dishwashers, but are recyclable if they get damaged.)

Also, the city did not ban small bags from meat, produce and pharmacy sections. Lundberg says to “wrap your meat with one or two bags to prevent cross-contamination” and also urges “washing all of your raw fruits and vegetables.” Mendonca said some Roplast bag users avoid cross-contamination by labeling their bags for specific uses, such as “P” for produce and “M” for meat.

This sanitary sensibility may seem like it’s, as Mendonca says, “about common sense.” But Sinclair’s research suggests not everyone is savvy.

“It’s really a new practice in our society, using these reusable bags,” he said. “People aren’t used to washing them; they aren’t used to carrying them around, or even using them….

“It represents more of a cultural shift than people are giving it credit for, so I think we need to start thinking about how we manage these things.”