Confronting the plastic pollution crisis is enough to give anyone a headache. Nearly 80% of plastic that has ever been made is still scattered across the planet, yet globally we continue to generate more than 450 million additional tons of plastic waste a year. A new study published in Nature Chemistry offers a glimmer of hope for both our throbbing noggins and our mountains of castoffs: Turning plastic into painkillers.
Last week, a team of biologists at the University of Edinburgh’s Wallace Lab unveiled a method for converting everyday plastic waste into paracetamol––also known as acetaminophen, a major component in Tylenol––using a harmless strain of Escherichia coli (E. coli) bacteria. While this isn’t the first effort to find microorganisms with a hunger for our plastic problems, it is unique in that it’s going after a lesser known climate enemy: Paracetamol itself. Nicknamed the “coal tar analgesic,” the medicine is derived from fossil fuels, and contributes to the approximately 52 megatons of CO2 the pharmaceutical industry emits annually––or roughly 4.5% of the world’s total greenhouse gas emissions.
Let’s be clear: This isn’t a call to ditch your meds. The proof-of-concept product isn’t hitting pharmacies just yet, but here’s the science behind how this promising research works.
The PET breakdown
E. coli is a common bacteria found in our environment, foods, water, and the intestines of people and animals. It’s largely harmless, but certain strains are known to cause infection when ingested. The researchers incubated a safe strain of E. coli with a compound found in the common plastic polyethylene terephthalate (PET)—aka the stuff that’s used to make water bottles and a lot of our food packaging. After 24 hours at room temperature, the researchers observed that 92% of the resulting product was the same as the active ingredient in paracetamol.
Normally this kind of synthetic reaction requires intense lab conditions. But the Wallace lab team discovered it could occur naturally inside the bacteria—similar to the way yeast ferments the sugars in grains to create beer. This low-energy process produces virtually no carbon emissions and sidesteps the need for high heat and strong catalysts typically used to break down PET.
A prescription for the planet?
Even though PET is among the easiest types of plastic to recycle, only 16% of it will get reborn as a new plastic bottle, which means other avenues to address the 61 billion plastic bottles the U.S. wastes annually are certainly welcome.
In fact, paracetamol is only one potential output of this process, says Stephen Wallace, a chemical biotechnology researcher and author of the study. “At scale, it offers a much more sustainable and circular way to produce essential medicines like paracetamol,” he says. Many drugs, including antihistamines and aspirin, also tap petrochemicals. “This opens the door to a new kind of sustainable manufacturing, where plastic waste becomes a feedstock for useful products rather than a pollutant,” he adds.
Still, the process isn’t ready for commercial scale, which means we’re a ways out from recycled painkillers at your local CVS. Plus, environmental advocates stress that even the most exciting scientific breakthroughs can’t replace the need to halt plastic production altogether. “Producing useful substances like paracetamol from plastic pollution may seem like a panacea,” Erica Cirino, Communications Manager at the Plastic Pollution Coalition, tells one5c. “However, we need to keep in mind that laboratory experiments that seemingly discover such ‘waste-to-resource’ uses of plastic have yet to be proven at scale, and are distracting us from implementing proven solutions.”