Next Green Thing: Bio-Plastics

In a laboratory in Cambridge, Mass., scientists are looking for ways to cut down on the amount of petroleum-based plastic in the world. We use hundreds of billions of pounds of the stuff globally, and every year we produce more than we did the year before. We recycle only a tiny fraction of the plastic - the rest goes to landfills, and here on Word of Mouth, we’ve told you stories about where else it ends up. Remember the garbage patch in the Pacific that’s twice the size of Texas?

Americans love to hate plastic, but the truth is, we can’t live without it. So, some scientists want to make a version that we don’t have to recycle. Reporter Shannon Mullen put together this story for our "next green thing" series.

In a rooftop greenhouse in Cambridge, Mass., some scientists are growing pots of switchgrass, a perennial prairie weed that used to cover North America from Mexico to Canada.

Metabolix is a small biotech company that’s figured out how to make plants grow plastic. Yes, plants - that grow plastic. It’ll be a few years before you see it on the shelf, but the news now is that the company has figured out how to grow enough bioplastic to go commercial. I’ll tell you how Metabolix makes it. But first, here’s why.

Unless you’re listening to this story while standing naked in the woods, chances are you’re inches away from something made of plastic. And even then, what’s your radio made of? Plastic is absolutely everywhere - cars, food containers, toys, myriad medical stuff our lives depend on.

But plastic has an even bigger problem than bad press. It’s made from petroleum. As President Bush said, "we have a serious problem - America is addicted to oil, which is often imported from unstable parts of the world."

At least we’ve admitted it. Americans use more than 29 million tons of plastic a year, but we recycle only a measly 7 percent of it, with no sign of big behavioral changes in sight. That’s where bioplastic comes in. It biodegrades over time in landfills or your kitchen compost bin, if you wait a few months to empty it.

Oliver Peoples founded Metabolix, and he’s the lead scientist behind its bioplastics. He says the plants already have the components to grow plastic as polymers inside their cells. What they don’t have are the enzymes to start the process.

The grass is baled and shipped to a refinery where the microscopic plastic polymers are extracted. Peoples says the process is similar to getting starch from corn. Machines shape the plastic into tiny pellets that can be made into a growing variety of products and packages, from gift cards to cosmetics cases.

The American Chemistry Council represents the $268 billion plastics industry, which welcomes bioplastics, and their potential to reduce the amount of unrecycled plastic. Keith Christman, Senior Director of Packaging for the ACC, said that’s a priority for the council. But he kept coming back to the benefits of petroleum-based plastic – namely that it’s lighter to ship than the alternatives, which saves gas, money, and cuts carbon emissions.

"Plastics reduce greenhouse gas emissions by 56% across the variety of applications, and reduce energy use by 26 percent," Christman says. "A plastic bag weighs one tenth of a paper bag. It takes 7 times as many trucks to move the same number of paper bags as it takes for a number of plastic bags."

Those stats hold for bioplastics, with a bonus, depending on your opinion of ethanol. The controversial biofuel can be made from what’s left of the spent switchgrass, and used to power the whole process. Unlike corn-based ethanol, with switchgrass as its source, there’s no effect on food prices.

One downside is the price – it does cost 8 to 10 percent more than standard plastic. And critics point out that both bioplastics and their petroleum-based counterparts only enable American consumers’ throw-away mentality. At Metabolix, Oliver Peoples counters - if it’s sustainable, it’s part of the solution.

"Everybody’s looking for a one-shot, single point answer to everything," Peoples says. "It doesn’t exist, it’s not going to exist. The reality of it all is we’re going to need lots of contributions, lots of singles, and there won’t be that many home runs. I think we’ve got a shot at a home run but it’ll be one among many."

(Picture of switchgrass courtesy of Metabolix)