Microbes convert polystyrene foam into biodegradable plastic

27-Feb-06

As per a study scheduled to appear in the April 1 issue of the American Chemical Society journal, Environmental Science & Technology, a special strain of soil bacterium Pseudomonas putida, converts polystyrene foam into a biodegradable plastic. This will solve the disposal and recycling problems the key component of disposable cups, plates and utensils into a useful eco-friendly plastic. The study is among the first to investigate the possibility of converting a petroleum-based plastic waste into a reusable biodegradable form. Pyrolysis was utilized- a process that transforms materials by heating them in the absence of oxygen, to convert polystyrene into styrene oil. The researchers then supplied this oil to P. putida, a bacterium that can feed on styrene, which converted the oil into a biodegradable plastic known as PHA (polyhydroxyalkanoates). Worldwide, over 14 million metric tpa of polystyrene are produced, according to the U.S. Environmental Protection Agency. Only 1% of polystyrene waste is currently recycled and the rest ends up in landfills. Although polystyrene represents less than 1% of solid waste generated in the United States, at least 2.3 million tons of it is dumped in U.S. landfills each year.