An enzyme could help solve the scourge of plastic waste

Every single minute a million plastic bottles are bought around the planet. You’ve read that right: one million bottles per minute. Within a couple of years that figure will jump to around 1.2 million a minute.

Last year alone half a trillion plastic drinking bottles were sold worldwide, translating into thousands upon thousands of bottles sold every second. Only around 14% of those plastic bottles are recycled with the rest adding to the scourge of plastic waste that has befallen our planet.

But solutions are on the way. In 2016 Japanese scientists discovered a species of bacteria that can break down the molecular bonds in polyester (polyethylene terephthalate or PET), one of the most commonly used plastics, by metabolizing plastic. The species of bacteria, Ideonella sakaiensis, could be deployed to consume large amounts of plastic waste by help of a special enzyme that the bacteria produce.

Then an international team of scientists took that discovery a step further by making the molecule in the enzyme produced by the bacteria even better at breaking down the type of plastic most commonly used in disposable water and soft drink bottles. The artificially tweaked enzyme can break down plastic bottles in a matter of days – the same bottles that would take centuries to decompose on their own naturally.

The scientists are working on ways to speed up the process even more by breaking plastic bottles down into their original components. That way, says one of the researchers, Prof. John McGeehan of the University of Portsmouth in the United Kingdom. “we can literally recycle [plastic] back to plastic, [which] means we won’t need to dig up any more oil and, fundamentally, it should reduce the amount of plastic in the environment.”

Upscaling the initiative to an industrial scale will be a challenge and consumer habits will also need to change. At the moment the chemical components of plastic bottles remain cheap so manufacturers don’t think twice about churning out an endless number of these bottles. What’s needed is a change in public perception whereby recycled plastic products come to be valued more by costumers so that manufacturers will be more inclined to start producing those.