ITHACA, N.Y. — When the COVID-19 pandemic hit, so did the demand for disposable medical gowns. Fast-forward to the present day and you’ll find most of these medical gowns sitting on top of landfills. Now, researchers at Cornell University say that even disposing of the “greener” biodegradable medical gowns has contributed to harmful greenhouse emissions.

A lot of single-use plastic medical gowns are either conventional or biodegradable. The biodegradable version is advertised as a greener option because it decomposes faster than typical plastic. This would, in theory, take up less space in landfills and emit less greenhouse gases. However, study authors found it was the opposite, with biodegradable medical gowns introducing harsher greenhouse gas discharges.

“There’s no magic bullet to this problem,” says Fengqi You, a Roxanne E. and Michael J. Zak professor in energy systems engineering, in the Smith School of Chemical and Biomolecular Engineering, in a university release. “Plasticized conventional medical gowns take many years to break down and the biodegradable gowns degrade much faster, but they produce gas emissions faster like added methane and carbon dioxide than regular ones in a landfill.”

You is also the senior faculty fellow in the Cornell Atkinson Center for Sustainability. The researchers notes that if he had to pick between the two, the more environmentally conscious choice would actually be the conventional medical gowns.

Producing biodegradable gowns is an environmental hazard

Results show they have an 11-percent higher eco-toxicity rate compared to conventional alternatives. Conventional gowns are environmentally and socially sustainable, argues the study authors. They are 14 percent less toxic to humans, cause 10 percent less greenhouse gas emissions, and are nearly 10 percent less toxic to freshwater.

The team also found that adopting landfill gas capture and utilization processes in landfills containing biodegradable gowns decreases greenhouse emissions by 9.79 percent. What’s more, it also reduces life-cycle landfill use by nearly 49 percent and can save at least 10 percent of fossil resources if using onsite power co-generation.

To make biodegradable gowns more environmentally sustainable than conventional gowns, makers will need to improve the gas capture efficiency above 85 percent.

“It’s nice to break down the plastic into smaller things,” explains lead author Xiang Zhao, a doctoral student at Cornell University. “But those small things eventually decompose into gas and if we don’t capture them, they become greenhouse gases that go into the air.”

The study is published in the Journal of Cleaner Production.