Can plastic-eating insects help with our microplastic problem?

Plastic pollution occurs in every ecosystem on the planet and lingers for decades. Could insects be part of the solution?

Previous research found that insects can ingest and absorb pure, unrefined microplastics—but only under unrealistic, food-scarce situations. In a Biology Letters paper, UBC zoologist Dr. Michelle Tseng and alumna Shim Gicole tested mealworms in a more realistic scenario, feeding them ground-up face masks—a common plastic product—mixed with bran, a tastier option.

Mealworms are nature’s scavengers and decomposers, able to survive up to eight months without food or water, and happy to eat their own kind when food is scarce.

After 30 days, the research team found the mealworms ate about half the microplastics available, about 150 particles per insect, and gained weight. They excreted a small fraction of the microplastics consumed, about four to six particles per milligram of waste, absorbing the rest. Eating microplastics did not appear to affect the insects’ survival and growth.

Dr. Tseng says the next step will be to learn from the insects’ digestive mechanisms how to break down microplastics, and scale up these learnings to address plastic pollution. “Perhaps we can start viewing bugs as friends. We’re killing millions of insects every day from general pesticides—the very same insects we could be learning from to break down these plastics and other chemicals.”