The Montgomery County Council is considering a ban on single-use plastic shopping bags in retail settings, known as the Bring Your Own Bag bill. The county follows over 500 jurisdictions in 28 states that have enacted similar legislation, including the city of Frederick, Prince George’s County, and Anne Arundel County in Maryland.
On Nov. 29, Benjamin Kay, an economist, and Margery Smelkinson, an infectious disease specialist, published an opinion piece on MoCo360 claiming that a similar plastic bag ban in San Francisco in 2007 led to an alarming increase in emergency room visits and deaths due to bacterial intestinal infections, presumed to be from foodborne bacteria. As evidence, they cited a 2012 paper published in a University of Pennsylvania law journal. This paper was soundly refuted by the health officer of the San Francisco Department of Health shortly thereafter.
There are several serious problems with basing important public policy on this evidence. First, the San Francisco Department of Health conducted a more refined analysis of available data and found that an increase in deaths from gastrointestinal infections that occurred in San Francisco from 2005 to 2010 was due to the bacterium Clostridium difficile, which is primarily a hospital-acquired infection and not a foodborne illness.
Second, the department points out that the authors were not able to demonstrate that people using reusable shopping bags were the ones who experienced an increase in gastroenteritis; claiming such an association is known as an ecological fallacy, like claiming that ice cream consumption leads to drowning, because both occur in the summertime.
Finally, the paper was never published in a credible, respected, peer-reviewed medical journal and thus did not undergo appropriate scientific scrutiny. For a finding of this importance, one would expect a rigorous investigation and response, including from the Centers for Disease Control and Prevention. None has occurred.
Of course, we must all exercise caution when handling foodstuffs. Bacteria commonly inhabit our living spaces, particularly kitchens and bathrooms, and there are estimated 9 million cases of foodborne illness in the United States each year. The authors of the 2012 paper cited another paper (supported by the American Chemistry Council) that found bacterial contamination in reusable grocery bags. However, they cited no instances of reusable bags causing illness, and I have been unable to find published reports in PubMed, the public database of the National Library of Medicine, or in a search of the CDC website of such occurrences up to the present time.
In contrast to the theoretical problem of reusable grocery bags causing foodborne illness, we are faced with increasing environmental and health problems related to plastic pollution and production. Let’s take this small step towards addressing the problem of unnecessary plastic and its waste by banning single-use plastic bags.
Diane Bild is a retired physician epidemiologist who lives in Montgomery County.
