The Food Standards Agency (FSA) warned that “bags for life” and reusable totes could lead to bacterial cross-contamination.
Most foodborne infections are caused by bacterial cross-contamination, which can make people feel unwell.
One study found that E.coli was present in eight percent of all reusable bags tested in the research.
The authors noted that reusable grocery bags were seldomly (if ever) washed and often used for multiple purposes.
They added: “When meat juices were added to bags and stored in the trunks of cars for two hours, the number of bacteria increased 10-fold.”
To use reusable shopping bags safely, the FSA advises shoppers to pack raw and ready-to-eat food separately into different bags.
The FSA says: “Take extra bags to pack cleaning products and other household items separately from food.”
It might be helpful to categorise which bags will be for raw foods, ready-made foods, and household items.
Using certain coloured bags for specific uses could help in keeping their uses separate.
However, if you have bags that look very similar, then labelling might be helpful.
“Check your bags for spillages after every use,” the FSA adds, and if it has occurred in a plastic bag, this should be replaced.
The FSA said cotton and fabric bags for life can be more useful as you can wash them.
One Stop Cleaning Shop said: “For bags that are made from cotton, or other materials such as polyester, these can generally be machine washed like how you would normally wash these materials.
“We recommend that you put them on a hot water setting (the hottest the material can stand without shrinking) with a detergent.
“This way the hot water as well as the detergent will kill any nasty germs lurking in the bag.”
There are other ways cross-contamination can occur, such as storing food ineffectively.
This is why raw meat, for example, should be stored on the bottom shelf of the fridge; otherwise, if its juices run, it could pool onto a shelf and its food below.