No one disputes that plastic, which doesn’t decompose, can be an environmental scourge that accumulates in large amounts in both our landfills and our bodies of water.
But now there may be a natural solution.
Mealworms, according to a study published in Environmental Science and Technology, can survive quite nicely on a diet of Styrofoam and other types of polystyrene plastic that were previously thought to be non-biodegradable.
”There’s a possibility of really important research coming out of bizarre places,” said Craig Criddle, a Stanford professor who supervises plastics research. “Sometimes, science surprises us. This is a shock.”
For the study, the scientists fed 100 mealworms 34-39 milligrams of Styrofoam a day – the equivalent of a small pill-sized dose. With the assistance of their gut microbes, the worms converted half of this plastic into carbon dioxide and then excreted the rest in the form of biodegradable droppings.
What took the scientists most by surprise was the worms’ follow-up health report: The Styrofoam-fed mealworms appear to be just as healthy as those fed a normal diet. In fact, their excreted waste seems to be safe enough to be used as soil for crops, although more research is needed to confirm this.
The real breakthrough in this study is the discovery that bug guts can break down what was believed to be a non-biodegradable product – especially one as ubiquitous and problematic for our environment as polystyrenes.
If the researchers can pinpoint the exact microorganisms responsible for this incredible feat, they may be able to replicate the process and engineer more efficient and powerful digestive enzymes.
As research engineer Wei-Min Wu from Stanford University said: “Our findings have opened a new door to solve the global plastic pollution problem.”
In the U.S. alone, more than 33 million tons of plastic get dumped into landfills each year, and less than 10% of that waste is recycled. The plastic can then pollute soils and waters and threaten marine ecosystems, and polystyrene foams like Styrofoam can take more than a million years to decompose, according to the EPA.
The team next plans to explore what happens when Styrofoam-munching mealworms are consumed by other animals, who are in turn eaten by even larger creatures, to see what the effect might be on food chains. They are also hopeful that they can find a marine equivalent to mealworms that could digest the plastic that typically finds its way into the guts of seabirds, turtles and fish.
From a non-sustainable, non-renewable, polluting material to an edible treat for a hungry tummy, this research definitely proves that what’s trash for us could be treasure for the environment.