Banning single-use plastic bags, like those used for carrying groceries, was in vogue in the 2010s and 2020s. A closer look at California and New Jersey’s plastic bag bans, however, suggests that the amount of plastic discarded per person increased after the bans went into effect. 

The researchers from the Frontier Group, Environment America Research & Policy Center, and the CALPIRG Education Fund, conclude that “Plastic Bag Bans Work.” Certainly, the number of plastic bags used in Alameda County, California, “dropped by more than 90%,” per shopping trip after its 2013 bag ban went into effect. That could mean fewer bags littering interstates, waterways, and beaches.

But after adjusting for population changes, the tonnage of discarded bags “rose from 4.08 per 1,000 people in 2014 to 5.89 per 1,000 people in 2022.” How can this be?

Consumers often substitute for “reusable” plastic bags, about four times as thick as “single-use,” plastic bags, and treat them like single-use bags anyway. The study concludes that policymakers should “eliminate harmful loopholes,” and prohibit sales of plastic bags of any thickness at checkout, while requiring fees for single-use paper bags. 

The New Jersey study, conducted by the Freedonia Group and commissioned by the American Recyclable Plastic Bag Alliance, found similar results. Total bag volumes “declined by more than 60%,” but plastic consumption for bags increased by three times due to higher thicknesses required to manufacture “reusable,” plastic bags that comply with the ban.

Paper bags, reusable cloth bags, and thicker reusable plastic bags require more natural resources to manufacture than “single-use,” plastic bags, and therefore need to be reused many times in order to offset the environmental impact of producing them. 

A 2006 study that took into account “global warming potential, depletion of resources such as fossil fuels, acidification, eutrophication, human toxicity, fresh water toxicity, marine toxicity, terrestrial toxicity and smog creation,” found that single-use plastic bags had the lowest environmental impact. The same study found that paper bags needed to be reused at least three times and cotton bags 131 times to offset the greenhouse gasses used in producing them.

The “single-use” label attached to plastic grocery bags ignores that they are often used more than once anyway, often as small trash can liners, which consumers have to buy when single-use bags aren’t available. A 2022 study of retail scanner data found that plastic bag ban bans or fees were associated with significantly higher plastic trash bag sales.

The Environmental Protection Agency (EPA) estimates that in 2018, 4.2 million tons of plastic bags, sacks and wraps were used in the U.S., and most were landfilled. That sounds like a lot, and it is, but it pales next to the U.S.’ 292.4 million tons of trash overall. Plastic bags, sacks, and wraps comprised only 1.4% of the U.S.’ overall trash generation in 2018. 

The intent of plastic bag bans is to reduce the impact of plastic pollution in waterways, beaches, and ecosystems, but consumer preferences result in unintended consequences. The authors of “Plastic Bag Bans Work” put it best: “A plastic bag ban that allows the weight of plastic bags discarded to increase, let alone establish a new peak level of plastic bag waste, cannot be considered a complete success.” 

Many people would call that a failure.