Scientists say bacteria could help solve microplastics pollution nightmare

Scientists have found a way to trap and remove harmful microplastics from the environment – using bacteria – in what may be a sustainable solution to one of the biggest threats to planetary health.

Sticky communities of germs known as biofilms are being used by researchers at Hong Kong Polytechnic University to sweep up microplastic particles, which – despite their size – are hugely damaging to natural ecosystems.

The team used a species of bacteria called pseudomonas aeruginosa, which is found commonly is soil and water, to capture microplastics in a bioreactor. That material was then processed, with the microplastics eventually released from the “biofilm matrix” using a dispersal gene.

The microbiologists behind the project hope the results that have been achieved in the lab can be reproduced in a real world setting – starting off with the removal of microplastics from wastewater treatment plants.

“It is imperative to develop effective solutions that trap, collect and even recycle these microplastics to stop the 'plastification' of our natural environments," said lead researcher Sylvia Yang Liu.

Polluted food, water systems
Pollution from microplastics – fragments smaller than 5 millimeters – has made its way into the world's food and water systems, and even into the air. This means humans ingest microplastics simply by eating, drinking and breathing.

Since the 1940s, humans have produced more than 8 billion metric tons of plastic. Less than 10 percent of that has been recycled.

Microplastic particles enter ecosystems via a variety of sources including discarded product packaging, the breakdown of synthetic clothing, microbeads used in cosmetics and countless industrial processes.

“Due to their huge surface area and adsorption capacity, microplastics can adsorb toxic pollutants, such as pesticides, heavy metals, and drug residues at high concentrations,” Lui said.

“This leads to biological and chemical toxicity to organisms in the ecosystems and to humans after prolonged unintended consumption of such microplastics.”

Because of their size, existing methods for microplastic disposal, such as incineration or storage in landfill, are limited.