From Plastic Waste to Paracetamol: How Science Turned Pollution into Medicine

“A Nature Chemistry discovery that transforms discarded plastic bottles into a common painkiller.”

What if plastic waste could heal instead of harm? Explore the stunning scientific discovery that turns everyday plastic into paracetamol.

"Necessity is the mother of invention," this famous saying is attributed  to the ancient Greek philosopher Plato, who wrote in   'The Republic' that “Our necessity is the real creator”. "Humans have been inspired to make many scientific discoveries to make their lives easier. It is truly nature's gift to man. Man moved from igniting fire to space exploration with his intelligence, it is thanks to man's own curiosity. Today, due to necessity and curiosity, humans have given birth to some chemical monsters. Which has brought weapons in front of humans today. But, there is also a truth that no matter how many inventions humans make to make life easier, nature takes a course with it or against it. Because nature is constantly changing.

In this article, instead of talking about the deeds of man, it is to talk about one of his researches that has raised a hope. A study published in the journal Nature Chemistry. Which is "the creation of paracetamol from plastic."

First of all, what is plastic? Let's Know!

Plastic:

Plastic is a man-made or semi-synthetic substance with a very large range, most often made from natural gas and mineral oil. It has become a part of human life due to its light weight, durability, flexibility, chemical resistance, low toxicity and low production cost.

Thus, the process of vulcanizing rubber by Charles Goodyear in 1839, can be considered as the beginning of the plastic era. Alexander Park patented the world's first man-made plastic in 1855. Afterwards, researchers rapidly expanded this field, discovering many plastic compounds such as polyethylene terephthalate (PET), polypropylene, polystyrene, polycarbonate, HDPE, etc.

But at the same time, its long-lasting quality became the bounty of human society and natural creatures and elements. Current news reports indicate that plastics in the form of microplastics are present in human organs, animal organs, and plant organs. This is really sensitive news. An estimated 8.3 billion tonnes of plastic is produced every year and 6.3 billion tonnes of plastic waste is generated against it. This waste causes damage to the environment. Plastic is found only in the sea, on its shores and in landfill sites.

Because of this, conscious governments are creating awareness among the people by formulating policies on plastic elimination. Governments are focusing on production, use, waste and regeneration from waste.

The breakdown of Plastic

Most plastics are non-biodegradable and remain in the environment for decades to centuries. This plastic gradually turns into microplastics from the photodegradation process under the influence of ultraviolet light of the sun rays, which produces a very harmful effect. Changes in Earth's climate also contribute significantly to the formation of microplastics. Factors that affect the decomposition of plastics include the type of material, sunlight, air, water, pollution, microorganisms, and landfill space.

Yes, one thing needs to be understood here that the definition of both decomposition and bio-decomposition of plastics are different. Fragmentation is the phenomenon of plastics breaking down into microplastics due to physical factors such as sunlight, air, friction, etc. Biodegradation is the process by which microorganisms break down plastic into simpler molecules. Conventional plastics are resistant to biodegradation. But this kind of plastic does not decompose, it produces effects such as turning into microplastics, releasing harmful chemicals into the soil and remaining a pollutant. This poses a serious threat to human health and the environment.

Polyethylene terephthalate (PET) is widely used in plastic packaging. Which are slowly entering our body in the form of microplastics. We don't know what the consequences of that are yet.

But what if this same plastic does not become our enemy and becomes a friend?

Scientists discovered that PET shares several structural similarities with certain drug molecules.

For example, there are some similarities in the chemical composition of a common drug like Paracetamol and the composition of PET plastic. Therefore, it became an interesting idea that if we break down PET and use the chemical elements in it properly, it can be useful in making medicine.

Attempts at scientific change

The first step in making this possible was taken by a team of researchers from University of Edinburgh, UK. They tried to break the molecular bonds of PET plastic by "chemical recycling." In this process, plastic is broken down into chemical components that can be used as a base for medicines.

They converted PET through a series of chemical reactions to produce para-aminophenol. It is  the main precursor used to manufacture paracetamol.

Indeed, this success can be attributed to the 19th century chemical process known as “Lossen Rearrangement”. Traditionally, this process requires heat, cell-damaging conditions, which do not make it suitable for biological systems. But Johnson and his team found an excellent solution, through which created a reusable biologically based process. They started this process with the help of bacterium E. coli, in which polyethylene terephthalate (PET) plastic was broken down into a simple chemical compound.The phosphate ions which present in culture medium, act as the catalyst for the rearrangement. 

This intermediate was then introduced into genetically modified E. coli bacteria. Due to the mutation of the conjugate gene coding for a specific enzyme, the bacteria completed all the steps necessary to complete the transformation into paracetamol. The result was very surprising, in which they obtained yields up to 83 % (and after optimizations, 92 % yield) of PET plastic that could be successfully converted into paracetamol.

Note: Lossen rearrangement: It is  a classical organic-chemistry transformation from O-acyl hydroxamates to amines via isocyanate intermediates, and can operate non-enzymatically inside E. coli, under physiological conditions, without killing the cells. 

From the laboratory to the industry

The successful results of this experiment have shown a new direction in the field of both chemistry and ecology. Scientists showed how plastic waste can be not only recycled, but also turned into high-value therapeutic drugs.

There are two major benefits to this process:

1. Plastic waste disposal and environmental protection

2. Affordable and available sources for the production of medicines

In this way, scientists have introduced a new "closed-loop" system. Where a useful product is made from waste and reused.

Hope in the field of medical research

This discovery has now opened up the possibility that more medicines can also be made from plastic waste in the future.

Different chemical elements can be obtained from different types of plastic by splitting their atomic bonds, which can be useful in medicine or industry. This will lead to conservation of natural resources.

Scientists believe that if this technology is widely applied, the plastic waste spread in the world can one day work as a medicine for diseases. What was once the cause of headaches, will now become the medicine for pain!

And finally!

With scientific progress, it is now evident that even elements once harmful to nature can become beneficial when used wisely.

This invention is a living example of how a "problem" can be turned into a "solution" through human intelligence and research. Which leads to the welfare of life.

Source:

“A biocompatible Lossen rearrangement in Escherichia coli” by Johnson, Valenzuela-Ortega, Thorpe, Era, Kjeldsen, Mulholland & Wallace, in Nat. Chem. 17, 1020–1026 (2025).