A month after posting about it on barfblog, Health Canada has some new suggestions about reusing cloth grocery bags:
When using cloth bags, make sure to wash them frequently, especially after carrying fresh produce, meat, poultry or fish. Reusable grocery bags may not all be machine washable. If you are using this type of grocery bag, you should make sure to wash them by hand frequently with hot soapy water. Plastic bins should be washed using hot soapy water on a regular basis as well.(1).jpg)
– Put your fresh or frozen raw meat, poultry and fish in separate bins or bags from fresh produce and other ready-to-eat foods.
– Putting your fresh or frozen raw meat, poultry or fish in plastic bags (the clear bags found in the produce and some meat sections work well) will help prevent the juices from leaking out and contaminating your reusable containers and other foods. Fresh produce should also always be put in plastic bags to protect them from contamination.
– If you are using your grocery bags or bins to store or transport non-food items, they should be thoroughly washed before using them for groceries.
There are some theoretical risks, but there isn’t anything I can find in the peer-reviewed literature that suggests reusable cloth bags are any riskier or less risky than the standard one-use-only plastic or paper from a cross-contamination between-uses standpoint. It would be nice to have that data, as opposed to the plastic-industry assertions that there is a measurable bacterial load in 25 bags in Toronto (with no pathogens, or real good indicators).
Comparisons to reusing hand towels don’t work for me (one-use-only paper vs. cloth), where the towel is part of the potential pathogen removal process (and is usually quite moist). Reusable cloth bags might be a factor in sporadic cases of Campylobacter or other pathogens, but more data is needed to make that determination. In cross-contamination there is a dilution effect when it comes to transfer. 1000 cfus of Campylobacter on the outside of the package of raw chicken might become 100 cfus when transfered to the bag, and then only 10 cfus when transferred to ready-to-eat apples. Drying out the bags (by turning them inside-out between uses) could reduce the bacterial loads enough to reduce risk. Maybe. The data just isn’t there. Washing them frequently (as HC suggests) is a good idea, and won’t increase risk, but I wonder how much it will actually decrease risk more than just letting them dry out.