Plastics Graduate to Green

In the Sixties, plastics stood for everything divorced from nature, but these days the material is literally coming down to earth. New containers and packaging made from corn-based plastics can be composted—though at very high temperatures, not in your kitchen bin. Still, it's a hopeful alternative when 100 billion plastic bags are tossed out each year and 1.5 million tons of petroleum-based plastic are made into bottles annually worldwide.

Biota has chosen a corn-based plastic bottle to hold its bottled water. The plastic is actually a polymer known as polylactide (PLA) resin, which is as smooth and clear as petroleum-based plastic. While consumers have been wary of "biodegradable" plastics since the early 1990s, when plastic bags intended to break down in landfills actually did not, PLA does decompose in 47 to 90 days, so long as it's composted in commercial facilities that operate at high temperatures.

Currently, several U.S. cities and counties—including San Francisco, Oakland and Seattle—are trying municipal composting with curbside collection, and at least one company, Nat-Ur, is specifically marketing its compostable plastic bags to these markets. If your city doesn't pick up compostables, you'll have to drop off your kitchen scraps and biodegradable plastics at the composting facility yourself (see Resources below for one near you). Wild Oats also accepts containers for composting in 30 of its stores.

Perhaps more appealing, PLA requires 25 to 55 percent less fossil fuels to produce than does plastic derived from petroleum. And, through the purchase of Renewable Energy Certificates (RECs), PLA manufacturer NatureWorks is buying as much energy from wind, solar and hydroelectric power plants as the company consumes in its production facilities and corporate offices. As a result, NatureWorks is offsetting all of the greenhouse gasses emitted during manufacture of the plastic.

PLA is also used in food containers at Dartmouth and Cornell colleges, at Oakland Coliseum sports events, at some supermarkets and in Newman's Own line of organic salad greens. "We had record growth in 2005 over 2004, exceeding more than 100 percent," says Mary Rosenthal, global communications leader at NatureWorks. "In addition, our growth is global: 40 percent of our volume is in Asia, 30 percent is in Europe and 30 percent is in North America." Steve Mojo, executive director of the Biodegradable Products Institute (BPI), which certifies compostable plastics, notes that "Part of this growth is because there's more interest in food-waste diversion than ever before, and part is because product quality has improved and the price differential is closing with the price of oil on the rise."