Everybody Panic! Reusable Shopping Bags Harbor Bacteria

By Eliza Strickland | June 25, 2010 12:04 pm

reusable-bagSo at some point you decided to do the right thing for the environment, and plonked down a couple of dollars for a reusable grocery bag. Bet you felt pretty good about yourself, huh? Well, some researchers have now come along to rain on your virtue parade. According to a new report (pdf), that bag is probably crawling with bacteria.

The researchers tested 84 bags, and found that all but one harbored bacterial colonies, and half contained coliform bacteria that suggest raw meat or uncooked food contamination. They also surveyed consumers about their use of these bags, and found that most people don’t keep separate bags for meat, and that they’re likely to tote clothes and all sorts of other things in these bags when they’re not grocery store-bound. Both these practices could allow for bacterial colonization.

But before you burn your reusable bags in a cleansing fire, consider this: The researchers also determined that either chucking a bag in the washing machine or rinsing it by hand reduced the bacterial counts to almost zero.

And The Washington Post dispassionately chimes in on another very relevant note:

The study was funded by the American Chemistry Council amid debate over a California bill that would ban single-use plastic bags. The council is opposed to that measure.

Related Content:
Discoblog: It’s In the Bag! Teenager Wins Science Fair, Solves Massive Environmental Problem
Discoblog: Got Too Many Plastic Bags? Recycle Them Into Nanotubes
80beats: Will California Be the First State to Ban the Plastic Shopping Bag?
80beats: Did Your Morning Shower Spray You With Bacteria?

Image: flickr/ foldablebags.com

MORE ABOUT: bacteria, plastic bags
  • Thoughts on the math

    I know I would wash my bag (but really I take plastic for the dog so I say would) and I know you would wash your bag, but the 97% that don’t make the problem. Apparently if you and I are standing in the room with 98 other people it is likely that only one would wash his/her bag.
    So how do the bacteria get on the bag and why do we need to educate people? “Cross contamination” think about it the germs get on the bag so they can get on the belt at Kroger and then on your food next in line.
    Please folks if you forgot to wash your bag just take paper or plastic… we wont hold it against you…really.

    If the University of Arizona and Lima Loma University conducted the study why is the funding source important unless we can trust Universities to be ethical?

  • ToneDeF

    I think the important point is that if the choice to use single-use bags is taken away (as the Cali law would do), then even the poor would need to use reusable bags. The poor are less likely to wash those bags (as they are more likely to use pay laundry mats, if any at all), thus they would be more susceptible to getting sick due to cross contamination.

    How about instead incentivizing reusable bags? Say a deduction of $0.05 per bag from your grocery bill?

  • Gil


    Cross-contamination is unlikely the main source of bacteria at the grocery store. The source of the bacteria are going to be the fresh produce, meat, and other non-processed food.

  • Gaythia

    I think that it should be noted that the American Chemistry Council (ACC) is not the American Chemical Society (ACS). It is the ACS that is the primary professional organization for chemists and related occupations.

    The American Chemistry Council describes itself as follows:


    “The American Chemistry Council (ACC) represents the leading companies in the business of chemistry. Our companies make the products that make modern life possible. ”

    Personally, I wouldn’t find it surprising to learn that some members of the ACC might think that modern life would not be possible without disposable plastic bags, but have they checked to see if any of their member companies manufacture laundry detergent?

  • http://doctorcrankenstein.wordpress.com/ Doctor Crankenstein


    Well said. This isn’t the first time I have seen an article about this and it amazes me that people think this is the biggest source of worry… Have they thought about the germs in the lift and the escalator on their way to the shopping centre?


    Out of all the things that the poor and the homeless come in contact with a reusable bag is going to be the LEAST of their troubles as far as sources of germs and disease go…

  • http://the50besthealthblogs.blogspot.com/ The 50 Best Health Blogs

    I’m guilty of still using plastic bags that end up in the landfill.


    Jim Purdy

  • http://www.Online-Grocery-Stores.net JLee

    I work in a grocery store and the thought never crossed my mind about bacteria, this sure gives me a different view point. I think I will just go back to plastic and put them in the recycling bin. Unusual but nice article.

  • http://lizplummer.com/blog Liz

    Well, I’ve been using a knapsack for carrying around my groceries for at least 10 years, the same one, put everything in there (it carries loads) and am still alive. It’s never seen the inside of a washing machine. Load of rubbish if you ask me, this so called research.,

  • Suz

    If you still use plastic for your meat and reusable for all the other produce isn’t that going to stop the cross contamination…everything in moderation!

  • http://www.bagwisely.com Steph

    Agreed with Suz…everything in moderation!

  • http://www.popsmell.com Designer Sunglasses

    A knack for personalized RayBan sunglasses that somehow make tough look glamorous.

  • Abcd

    Both these practices could allow for bacterial colonization.


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