Do you use reusable bags for our groceries? It’s a great way to cut down on waste and protect the environment. But you may be packing more than food in your reusable grocery bags – as these convenient carrying cases can become contaminated with germs.

Luckily, a few simple steps can help prevent this.

What causes contamination?

Infectious disease specialist Susan Rehm, MD, says meats are a common contamination culprit.

She says grocery bags often come into contact with poultry, meats and produce that have bacteria on them.

Cross-contamination can occur when meat, produce, and pre-cooked foods are placed in the same bag.

“Let’s say we’ve had a ‘leaker’, one of our chicken containers, or something like that. Well, that all contains bacteria, which contaminates the bag, so the next thing that goes into the bag can also become contaminated,” Dr. Rehm says.

University of Arizona researchers have found reusable shopping bags can harbor multiple bacteria, including E.coli.

How can you avoid bacteria?

Here are some tips from Dr. Rehm to keep your bags from harboring harmful bacteria:

• Wash your bags regularly. Your best defense is to wash your bags after each trip to the store, but 97 percent of shoppers admit they have never washed their reusable bags.
• Only use grocery bags for groceries. “It’s really important not to use grocery bags for other purposes. They should be designated grocery bags,” Dr. Rehm says.
• Consider labeling bags. “You can use one for meats, one for produce, that type of thing, so you don’t get into cross-contamination between your own bags,” Dr. Rehm says.
• Don’t store bags in the car. Dr. Rehm also suggests storing your bags some place other than the trunk of your car. She says it especially an issue in the summer when the heat creates an optimal environment for bacteria to multiply.

If you do these simple things, especially wash your bags regularly, you greatly reduce the chance of contaminating your food.

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