Single-use plastic is a problem but bag ban isn’t the answer, not yet

Plastic, plastic everywhere. The world’s oceans are stewing in 160 million tons of plastic, and each year another 8 million tons of trash float in, mostly by way of rivers. A thousand miles inland, plastic is in the air we breathe and the water we drink. Microscopic bits were recently discovered by researchers in Denver and Rocky Mountain rainwater. These microplastics come from degraded packaging, household products and clothing fiber.

If it’s not in the air or the water, it’s in the ground. Because only 9% of plastic is recycled, most plastic waste ends up in landfills or incinerators. Now that China is no longer taking the West’s recycling, even plastic tossed in the recycling bin will end up in the dump or up in smoke.

Plastic takes decades to centuries to decompose, so each temporary use produces a long-term

waste problem.

Denver City Council members working to reduce single-use plastic bags should be commended for their concern for the growing environmental and potential human health problem posed by the accumulation of plastic waste. Their proposed ban on single-use plastic bags, however, is problematic because the alternatives aren’t much better.

For example, paper bags require more energy to make and have a larger carbon footprint than plastic bags. Reusable plastic bags are better than singleuse ones as long as they’re reused multiple times. If not, they’re worse for the environment because they’re more energy intensive to produce and recycle.

While the city of Austin’s single-use plastic bag ban achieved an impressive 75% annual reduction in the consumption of single-use plastic bags, the law prompted greater use of “reusable” plastic bags. These bags, however, ended up in the recycling bin or trash after one or two uses.

Plastic alternative bioplastic has great potential but is also not without cost.

Unlike regular plastic, a petroleum product, bioplastic is made from plants or engineered by micro-organisms. While innovators are scaling up bioplastics made from algae, mushrooms and agricultural waste, bioplastics made from vegetable starch compete with food production, much like ethanol.

While bioplastics are biodegradable, most cannot break down in the average garden compost; they require industrial processing first. If landfilled, bioplastics can emit methane, a greenhouse gas more potent than carbon dioxide.

Bioplastic is perfect for institutions such as the Denver Museum of Nature & Science and the Denver Botanic Gardens, which offer bioplastic lunch utensils, collect the waste on site and take it to an appropriate facility for industrial composting. By contrast, bioplastic grocery bags will leave the grocery store and are more likely to end up contaminating plastic recycling processing or in a landfill.

Unlike most bioplastic or traditional plastic, a cotton tote bag is easily compostable; however, it requires considerably more energy to make than a plastic bag. A Danish study found that a cotton bag must be used at least 50 times to be worth the environmental costs to grow the cotton and the chemicals used to manufacture the bag.

Finally, there’s the question of the human cost. A one-size-fitsall law does not allow for individual circumstances. Do we really want to make a senior citizen or mom with a restless toddler return to the car to retrieve a forgotten tote? Do you want to put a less-than-securely wrapped pot roast or greasy rotisserie chicken in a cloth bag with the cereal? And what about the green beans, apples and bulk nuts? While bioplastic and reusable synthetic and natural fiber bags will likely replace single-use petroleum plastic bags in the future, right now plastic bags have their place.

Given the current limitations of plastic alternatives, the benefits of a ban will not likely exceed costs at this time. The Denver City Council should consider other ways to reduce single-use plastic. Could the city partner with grocery stores to encourage the consistent use of reusable bags? How can city government agencies reduce in-house, singleuse plastic and move toward bioplastic? Could the city partner with the private sector to collect bioplastic waste for composting? The goal is to pave the way for a plastic-free world without forcing people to choose alternative products that at this

time are no better.