Plastic is a notorious polluter. When not disposed of properly, plastic products litter the streets and can wash into storm drains or rivers. Eventually, it can wind up in the ocean. And lots of it has.
About 8 million metric tons of plastic enter the ocean each year. According to the National Oceanic and Atmospheric Administration, plastics accounted for five of the top 10 kinds of trash picked up during the 2017 International Coastal Cleanup. Plastic harms the marine life that consume it, and eventually humans, as plastic makes its way up through the food chain.
To address this environmental and public health issue, the world has put plastic bans into effect. Several countries, as well as some U.S. states and towns, have banned plastic straws, shopping bags, or single-use plastics altogether. Regulations on plastic shopping bags are some of the most common.
What's a Plastic Ban?
Plastic bans typically prohibit a particular type or form of plastic, not all plastics. Bans on single-use plastic shopping bags or Styrofoam takeout containers, for example, are popular throughout the U.S. Eight states now ban single-use plastic bags as of November 2019 and over 240 local governments have single-use bag bans or fees.
But this kind of legislation isn't limited to the U.S. A number of African countries, including Tanzania and Kenya have also banned plastic bags. The Economist reports that African countries have taken the lead on plastic bans because the problem is highly visible. Waste collection and recycling rates are low, and trash piles up faster. Also, African countries don't manufacture and export a lot of plastic, so there's no strong industry pressure to keep plastic bags in circulation.
The idea behind the bans is that they'll prevent more plastic from entering waterways or otherwise polluting the environment. Since stores won't be giving these products to consumers, consumers won't need to worry about proper disposal.
According to a United Nations report, as of July 2018, 127 countries regulate plastic bags in some way. Image from velkr0. CC BY 2.0
How Plastic Bans Work
Some environmentalists acknowledge that bans, at least those that don't regulate plastic bag substitutes, have varying success rates. For example, when Chicago banned plastic bags in 2015, it didn't prohibit all plastic bags. Stores could use thicker bags that were arguably reusable. The city realized the error, and in 2017 they instead implemented a tax of 7 cents on all checkout bags. A study from the nonprofit behavioral science firm ideas42 found that once the tax went into effect, about half of consumers switched to using reusable bags. The remaining half stopped using bags altogether.
Other research has found that increases in trash bag purchases offset reductions in plastic bag use from these bans. Such studies recommend imposing small fees for plastic checkout bags. The Surfrider Foundation, which advocates for policies that help the ocean, also states that the most effective regulations include small fees for single-use bags. These small fees are enough to encourage people to use reusable bags or no bags at all.
The Environmental Impact
Even if bans on single-use plastic bags do cut down on plastic use, that might not help the environment much. Paper or cloth bag substitutes actually have bigger environmental impacts. A 2018 study from the Danish government assessed the life cycle of grocery bags and found that, compared to a standard plastic checkout bag, a cotton bag would need to be used 7,100 times to make up for the environmental impact of making that bag. Reusable polypropylene bags need to be used 37 times and paper bags need to be used 43 times. The original report (in Danish) can be found here.
Although paper and cloth decompose much faster than plastic, the impact of making these bags and their widespread use might have big consequences for the environment.
Plastic bans that don't regulate single-use plastic substitutes might lead to less plastic pollution, but they might not help the environment overall. They might even increase paper use and production, trading one environmental evil for another.