Could mealworms solve our plastic problem?

We might finally have an answer for all those Styrofoam coffee cups that get thrown away.

Gerald HerbertAP Photo/File
Cornbread stuffed with mealworms was part of a Thanksgiving-inspired meal featuring foods made with insects at the Audubon Insectarium in New Orleans, Nov. 11, 2011.

Researchers at Stanford University have finally figured out a partial answer to the world’s plastics problem: mealworms.

Mealworms, the larvae form of darkling beetles, can apparently subsist on a diet of foamed polystyrene, better known as Styrofoam, with no ill effects to their system, thanks to special bacteria in their guts. This could be very hopeful news in light of the amount of Styrofoam and other petroleum-based plastics we consume: Americans throw away 25 billion Styrofoam cups every year, and they will not decompose for thousands of years.

"Our findings have opened a new door to solve the global plastic pollution problem," said Dr. Wei-Min Wu, a lead researcher on the study, in a press release.

The scientists fed Styrofoam to a sample population of mealworms, while feeding their control group a normal diet of bran flakes, according to a study by the Stanford University and Beihang University research team in Environmental Science & Technology.

In the lab, 100 mealworms ate between 34 and 39 milligrams of Styrofoam – the weight of a few feathers – per day. The worms converted about half of the Styrofoam into carbon dioxide gas, as they would with any food source, and excreted the rest as biodegraded fragments.

After a month, the Styrofoam-fed mealworms were as healthy as those eating the bran flake diet, said Dr. Wu, and their waste appeared to be safe to use as compost for crops.

"There's a possibility of really important research coming out of bizarre places," said Craig Criddle in the release. Dr. Criddle is a professor of civil and environmental engineering who supervises plastics research by Wu and others at Stanford. "Sometimes, science surprises us. This is a shock."

In 2009, a Taiwanese high-school student named Tseng I-ching discovered the bacteria that enables mealworms to digest Styrofoam safely, but could not identify how the process occurs.  

In the next leg of their scientific journey, the researchers at Stanford and Beihang will investigate whether mealworms and similar insects can consume polypropylene, microbeads, or bioplastics. In addition, they want to find out how the mealworms' Styrofoam-based diet affects animals further up the food chain. 

Dr. Wu and his colleagues are also interested in finding a marine counterpart to the mealworm, to address the nearly 5 trillion tons of plastic floating on the world's oceans.

You've read  of  free articles. Subscribe to continue.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.