It's been more than a year since the City of Toronto passed its plastic bag bylaw requiring stores to charge five cents for every plastic bag requested. And while the city has been successful in creating a plastic bag social stigma ("You want three bags?!") a report released recently out of California and Arizona show reusable shopping bags can pose serious health risks.

Researchers at the University of Arizona at Tucson tested reusable shopping bags and found that half contained coliform bacteria, and 12 per cent contained E. coli. Bags can be contaminated by not properly separating produce and raw meats, as well as using the bags for non-grocery items such as athletic wear.

So now, it's up to you. Keep the environment healthy? Or keep yourself healthy?

Or...you know...just wash your bags once in a while.