‘Compostable Plastic’ Doesn’t Live Up to Its Environmental Claims. Here’s What You Can Focus On Instead
Rachel Ramirez | November 3, 2022 | CNN
It’s no longer a secret that single-use plastic is harming the planet. Not only does the process of creating these materials emit enormous amounts of planet-warming gases, but they also can take centuries to decompose in a landfill.
So as demand for climate action escalates and the dangers of plastics become more evident, consumers are turning to so-called compostable and biodegradable alternatives for things like food containers, cups, plates, cutlery and bags, in hopes of mitigating further climate and environmental harms.
But unfortunately, researchers say those products are also a problem.
A new study conducted in the UK found that 60% of products labeled as compostable do not fully break down in home compost. And unlike conventional plastics, these alternatives are largely unregulated, despite their advertised benefits.
“In the lab, where [these plastics] have been tested and have been paid for by a manufacturer, they behaved in one way and they’ve been determined to be compostable in a home composter,” Danielle Purkiss, researcher and lead author of the study, told CNN. “But what’s happened is we’ve seen a lot of these pieces of packaging with certification still don’t break down in these different home composting conditions.”
The study shows “there’s a problem with the lab testing versus the real-world conditions where these materials are being disposed,” Purkiss told CNN.
The real impact of ‘compostable’ plastic
Although compostable and biodegradable packaging and flatware are touted as being environmentally friendly, they are still resource- and energy-intensive to produce, according to Judith Enck, a former Environmental Protection Agency regional administrator and now president of Beyond Plastics, a non-profit focused on research and consumer education.
In addition to the greenhouse gases released from industrial facilities making these products, the crops used as feedstock, such as corn or sugar beets, also require significant amounts of fossil fuels, farmland and water to create them — all resources that could instead go to actual food, Enck said.
Though compostables are still slightly better than conventional plastics, Enck told CNN, “people shouldn’t fool themselves into thinking that it actually gets composted.”
“There’s a bit of greenwashing going on here,” she added.
Researchers say the messaging has not been clear around how sustainable these compostable options are. One of the key findings of the report, Purkiss said, is that people are confused and don’t know the meaning of the labels on compostable and biodegradable plastic items.
The bottom line is that companies still use some fossil fuels in these products, yet continue to market them as sustainable, which leads to improper disposal of plastic waste. Biodegradable plastic for instance, while bio-based, can still be made at least in part with fossil fuels.
Ultimately, compostable products are designed to fully decompose only at industrial compost facilities that regulate the temperature to achieve peak composting efficiency. But most of these products don’t wind up there, Enck and Purkiss said – they end up at regular landfills, where they will persist for years, just like conventional plastics. Or they will be burned in trash incinerators, where they release methane, a potent greenhouse gas.
“It pains me to say this because I want non-plastic alternatives to work,” Enck said, “but there really is no such thing as biodegradable plastics, and compostable packaging really only gets composted at high-temperature composting facilities.”
