Plastics have huge carbon emissions: the production of this petroleum-based material brings at least 100 million tons of carbon emissions per year. Today, an American research team has invented an inexpensive way to make plastic from sugar and corn cobs. If the plastic can be produced at a low enough cost, then one day it will replace the world's most common plastic & mdash; polyethylene terephthalate. Food packaging bags, soda bottles, and even polyester cotton contain PET.