How Mealworms Could Eat Away Plastic Waste

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The plastic consumption culture in the United States is getting out of control. Everywhere we turn, we’re surrounded by plastic. Plastic is such a versatile material that it’s used in the production of nearly everything these days. Even if you try to minimize your plastic purchases, it’s nearly impossible to avoid completely unless you live in a cabin in the middle of nowhere with no modern conveniences.

Plastic consumption rates are increasing rapidly. Did you know that over the past 10 years, we’ve produced more plastic than in the entire last century? As the population continues to explode, so will our plastic waste if something doesn’t change. And, since plastic can take 500 to 1,000 years to degrade, nearly every single piece of plastic that has ever been manufactured still exists today in some form.

Many people think that because plastic is recyclable, it’s a good choice. Unfortunately, we recover only 5 to 10 percent of the plastics we produce. Much of it ends up in the landfills, where it never biodegrades, and a lot of it ends up in our oceans, too.

So, what’s the answer? You can find plastic-free advocates providing helpful tips for reducing your plastic consumption, which is great, but we need a solution to the plastic pollution problem. Fortunately, it looks like researchers may have found a way to safely dispose of plastic waste — without human, animal or environmental harm.

Don’t Get Squirmy

You might be surprised to learn that the potential solution researchers have uncovered is worms — mealworms in this case. Many of us raise mealworms as a food source for backyard chickens, but it appears they may be able to have an even greater impact on our lives.

Stanford research has demonstrated that mealworms (darkling beetle larvae) can live quite happily on a diet consisting solely of polystyrene, more commonly known as Styrofoam — a material previously thought to be completely non-biodegradable. This form of plastic is one of the toughest on our environment, and Americans throw away 25 billion Styrofoam coffee cups every year.

In their experiment, Wei-Min Wu and his colleagues at Stanford’s Department of Civil and Environmental Engineering raised 100 mealworms from birth on a strict diet of Styrofoam. They discovered that mealworms can digest Styrofoam because their guts contain a specific type of bacteria that can break it down.

These mealworms could be one of the solutions for the plastic waste problem. Photo: Shutterstock

As part of their daily diet, each mealworm consumed 34 to 39 milligrams of Styrofoam per day. They were able to convert half of that to carbon dioxide, just like they would with any other food source, and they excreted the other half within 24 hours as nontoxic waste that looks similar to tiny rabbit droppings. Initial thoughts are that their waste appears to be safe to use as soil for growing crops.

The control group was fed bran, which is the typical diet of a mealworm. At the end of the study, the worms that ate Styrofoam were found to be as healthy as the group that ate bran. The Stanford research team is still watching these worms to study any possible long-term effects that could appear after multiple generations or after being consumed as a food source by another creature.

The research, which was published in Environmental Science and Technology, is the first that has been able to offer detailed evidence of how plastic can be degraded by the bacteria in the gut of an animal. The hope is that this new understanding of how mealworms can carry out this amazing process will lead to novel ways to safely manage plastic waste.

Eating Away at Other Problematic Plastics

Earlier research done by Wu and others showed that waxworms, which are the larvae of Indian meal moths, have microorganisms living in their guts that can biodegrade polyethylene. This problematic plastic is used to make pliable products like trash bags.

A group of researchers are collaborating on ongoing studies into how mealworms and other insects can biodegrade plastics. This team is led by Craig Criddle, senior fellow at the Stanford Woods Institute for the Environment, and includes Jun Yang of Beihang University in China and other Chinese researchers.

These researchers seek to identify whether microorganisms living in the gut of mealworms and other insects can biodegrade plastics like polypropylene (which is used in a variety of products that includes everything from textiles to automotive parts), microbeads (those controversial tiny plastic bits that are used in skin-exfoliant products) and bioplastics (plastics created from renewable resources like corn). They are using a full-spectrum, “cradle-to-cradle” approach to understand what happens to plastic materials that are eaten by small animals, which are later eaten by other animals.

A Solution to the Great Pacific Garbage Patch?

Billions of pounds of plastic currently reside in our oceans, and this plastic makes up about 40 percent of the world’s ocean surfaces. Approximately 80 percent of this ocean pollution makes its way there from the land. It’s no wonder the Great Pacific Garbage Patch has formed.

Researchers hope to identify marine-dwelling animals that could also digest plastics like mealworms and waxworms. If they can identify the right species, they can hopefully eliminate the Great Pacific Garbage Patch and the rest of the plastics responsible for the death of countless seabirds, fish, turtles and other marine life.

It may be a while before this vision reaches reality, though. Researchers say more time and effort is needed to understand what conditions make plastic degradation more favorable. When they gain this understanding, it may give scientists the information they need to create enzymes that are powerful enough to degrade plastics. This knowledge could even help them design polymers that won’t accumulate in our food chain or environment.

Keep Doing Your Part to Reduce Plastic Pollution

While the research into using mealworms, waxworms and other insects to solve the plastic pollution problem looks hopeful, you still need to do your part. Reduce, reuse and recycle everything you can and make sure your trash ends up where it’s supposed to go.

How do you reduce plastic waste and pollution in your home and community?

Feature image courtesy of Shutterstock

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Chrystal Johnson

Chrystal Johnson, publisher of Happy Mothering, founder of Green Moms Media and essential oil fanatic, is a mother of two sweet girls who believes in living a simple, natural lifestyle. A former corporate marketing communication manager, Chrystal spends her time researching green and eco-friendly alternatives to improve her family's life.