While they reduce waste, reusable grocery bags can have problems of their own.
Montgomery County's new bag tax is almost two weeks old. Although many residents appear to have adjusted to the new law, some scientists are urging them to take precautions when using reusable bags.
How well residents are adjusting to the county's new bag law depends on which people you ask. Joseph Wambea is on-board.
"I think it's a good incentive for people to develop a new habit," says Wambea.
While Donna Jordan is not: "Our motto should be, 'Welcome to Montgomery county, what's in your wallet.'"
Adding to the criticism is a study co-authored by two environmental scientists, Charles Gebra of the University of Arizona and Ryan Sinclair of Loma Linda University's School of Public Health. Their findings suggest reusable bags used to carry food can pose a threat to public health due to harmful pathogens which can accumulate over time.
"Probably gets into the bags from handling raw meat products like hamburger that leaks then the bacteria can grow to large numbers," explains Professor Gerba. "Also we found that 50 percent of the people used their bags for other things like hauling dirty laundry, and carrying various other thing that serve to contaminate the bags."
Storing the bags in your car trunk can accelerate the problem. In fact, Gebra and Sinclair say finding a washable bag and laundering it occasionally is key to avoiding contamination. The study also recommends reusable bag makers print advisories reminding users to launder them.
The report was underwritten by the American Chemistry Council, which represents a number of plastics manufacturers and some reusable plastic bag makers. Gerba and Sinclair claim the findings were not influenced by the Council.