Researchers have developed a method to convert polyethylene terephthalate (PET) plastic waste into acetaminophen using genetically engineered bacteria, offering a dual solution to plastic pollution and unsustainable pharmaceutical manufacturing. This process eliminates virtually all carbon emissions associated with traditional acetaminophen production, which relies on fossil fuels like crude oil. Thousands of tons of fossil fuels are currently used annually to manufacture this widely consumed painkiller, contributing significantly to climate change.
The Science Behind the Conversion
A team from the University of Edinburgh’s Wallace Lab genetically modified harmless E. coli bacteria to transform terephthalic acid, a molecule derived from PET plastic via chemical degradation, into acetaminophen’s active ingredient. The process leverages a fermentation technique similar to beer brewing, completing the conversion in under 24 hours at room temperature. Remarkably, 90% of the reacted material yielded acetaminophen.
A key discovery was identifying the “Lossen rearrangement,” a chemical reaction previously observed only in harsh laboratory conditions, occurring spontaneously within the bacteria. Phosphate ions naturally present in the cells catalyze this reaction, enabling biocompatibility. Further genetic modifications introduced genes from mushrooms and soil bacteria, allowing the E. coli to synthesize acetaminophen efficiently.
Environmental Implications
PET plastic, used in water bottles and food packaging, generates over 350 million tons of waste yearly, polluting oceans and landfills. While recyclable, conventional methods often produce lower-quality plastics that perpetuate pollution cycles. This new approach repurposes PET waste into a high-value pharmaceutical, advancing circular economy principles.
Table: Key Advantages of Microbial Acetaminophen Production
| Aspect | Traditional Method | New Microbial Method |
| Carbon Emissions | High (fossil fuel-dependent) | Virtually none |
| Feedstock | Crude oil | PET plastic waste |
| Product Time | Days/Week | <24 hours |
| Yield Efficiency | Varies | Up to 92% |
Path to Commercialization
The research, funded by an EPSRC CASE award and biopharmaceutical company AstraZeneca, highlights engineering biology’s potential to merge chemistry and biotechnology for sustainable chemical synthesis. However, scaling the technology for industrial use requires further development. The University of Edinburgh’s commercialization service, Edinburgh Innovations, is actively seeking collaborators to advance this innovation.
This breakthrough demonstrates how plastic waste can serve as a resource for high-value products, potentially extending to other pharmaceuticals and chemicals. By addressing both plastic pollution and fossil fuel dependence, the method exemplifies integrated solutions for global sustainability challenges.
