Pain relief from plastic: microbes convert waste into paracetamol

A widely used painkiller could soon be manufactured more sustainably, thanks to a breakthrough that turns plastic waste into paracetamol using engineered microbes.

Researchers at the University of Edinburgh have developed a biotechnological method to transform polyethylene terephthalate (PET) – the plastic found in water bottles and food packaging – into the active ingredient of paracetamol, using genetically modified E. coli. The work, [1] published in Nature Chemistry, demonstrates how synthetic biology can upcycle pollutants into vital medicines.

The team’s approach involved feeding terephthalic acid, a breakdown product of PET, to reprogrammed bacteria in a fermentation system. Within 24 hours and under mild conditions, the microbes had converted nearly 90% of the input material into paracetamol. Notably, the process generated minimal carbon emissions and was carried out at room temperature, presenting a significantly greener alternative to the fossil-fuel-based manufacturing routes currently in use.

“Plastic waste is typically considered an environmental problem,” said Professor Stephen Wallace, Chair of Chemical Biotechnology and lead author. “Our findings show that with the right tools, it can also be a valuable resource.”

Conventional paracetamol production relies on petrochemicals like benzene, extracted from crude oil. The new method offers not just a route to decarbonise part of pharmaceutical manufacturing, but also an avenue for addressing global plastic waste at source.

While further optimisation is needed before scale-up, the research points to a future where ‘living factories’ – microbial strains engineered for specific chemical outputs – could help decouple essential drug production from fossil inputs.

The study was supported by AstraZeneca, the Engineering and Physical Sciences Research Council (EPSRC), and Edinburgh Innovations. It adds to the University’s growing portfolio of research in engineering biology – a field at the intersection of synthetic biology, chemical engineering, and environmental sustainability.

More information online

1.    A biocompatible Lossen rearrangement in Escherichia coli published in Nature Chemistry