Iowans who like “going green” with reusable grocery bags may be helping the environment, but those cloth bags may present a potential health problem. A study by the Country Living Association shows if not used properly, the bags can be a haven for bacteria.

Cindy Brison, a food and nutrition extension educator, says you have to be careful how you use the bags. “Paper goods are fine in there, all different sorts of dry goods but if you start taking home any sort of raw meat, it’s really important you have them in another plastic bag just to keep any juices from getting out,” Brison says.

“If you do happen to get any juices of out from chicken or beef or anything like it, you can try to take them home and hand wash them with soap and water,” she says.

Brison says if you use a washing machine, it may destroy the recyclable bags. Also, let them air dry and don’t use the drier. She says you may want to designate bags for certain uses to prevent cross-contamination.

She says, “So maybe you have one bag just for fruits and vegetables and one bag that you use strictly for fresh meats, then you won’t have any problems with things going back and forth.” Brison says it’s also important to store these bags properly between trips so they don’t get dirty.

“I fold them back up and put them all inside one bag and place them in an area that is clean,” she says. “Either hang them inside your door so you can take them as you go or put them in the back, in the corner of my van where I know it is going to be clean and nothing else is going to get on them. I’m not going to put anything else on top of them.”

She says to avoid storing the bags in your trunk as it could be an atmosphere for bacteria to grow. Brison says to designate one reusable bag for chemical products, like soaps and cleaners. You don’t want to risk the danger of having a container leak and then later using that bag for fresh produce.