Mealworms Make Styrofoam Biodegradable By Digesting It

Styrofoam cups, plates, takeout containers, and coolers fill landfills around the world—the expanded polystyrene is impossible to recycle, and takes centuries to break down naturally. It’s such an enormous environmental problem that cities across the United States have started banning its sale. But though the bans cut down on the creation of new unrecycleables, they don’t address the millions of tons of styrofoam already in existence.

Fortunately, scientists have discovered a possible solution: mealworms. The tiny beetle larvae are able to achieve something that, thus far, no human recycling technology has. They can break down polystyrene.

According to two new studies by Stanford University research engineer Wei-Min Wu, each worm can safely consume several dozen milligrams of styrofoam a day thanks to microbes in their stomachs that can biodegrade plastic. The worms, which are the larvae form of the darkling beetle, eat the styrofoam, digest it, and excrete it in small biodegradable fragments. According to Smithsonian, the fragments look like “tiny rabbit droppings” and, so far, seem safe to use as soil for plants. 

Though scientists are still studying the long-term effects of styrofoam on the mealworms, so far, no negative side effects have been observed.

The studies have huge environmental implications: as NBC News explains, “Understanding how bacteria process a plastic thought to be practically indestructible, let alone edible, may lead to a way of disposing safely of the millions of tons of non-recyclable plastic thrown away every year.”