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Polystyrene Fact & Fiction

CFCs and Blowing Agents

Chlorofluorocarbons (CFCs) are known to harm the Earth’s stratospheric ozone layer. Polystyrene foam foodservice products are not manufactured with chlorofluorocarbons (CFCs) or any other ozone-depleting chemicals. In fact, Dart never used CFCs in manufacturing molded foam cups. Those manufacturers of polystyrene foodservice products that employed CFCs in their manufacturing operations, ceased using them by 1990.* According to the U.S. Environmental Protection Agency (EPA), only two to three percent of CFCs used in the United States in the 1980s went toward production of polystyrene packaging products. Even so, polystyrene manufacturers exceeded government goals and timetables during the phase-out period of CFCs in the late 1980s and were at the forefront of US industry in switching to better alternatives.†

Polystyrene foam products are about 90 percent air and only 10 percent polystyrene. When polystyrene foam packaging is produced, a "blowing" or "expansion" agent is used in the process.

Polystyrene foam products are now manufactured primarily using two types of blowing agents: Pentane and Carbon Dioxide. Carbon dioxide (CO2, or other hydrocarbons in some cases) is non-toxic, non-flammable, and does not contribute to low-level smog, nor does it deplete the stratospheric ozone layer. However, CO2 does have the potential to produce global warming. The carbon dioxide used for this technology is recovered from existing commercial and natural sources. As a result, the use of this blowing agent technology does not increase the net levels of CO2 in the atmosphere.

Pentane gas has no effect on the upper ozone layer, although, if not recovered, it can contribute to low-level smog formation. Where smog formation is a large concern, many manufacturers use state-of-the-art technology to capture pentane emissions. The majority of Dart plants recapture and reuse as a fuel a substantial portion of the pentane released in the pre-production processes.

* Alexander, Judd H. In Defense of Garbage. Westport, CT: Praeger Publishers, 1993. 55.
† Natural Resources Defense Council Environmental Defense Fund Friends of the Earth. Statement of Support for The Foodservice Packaging Institute’s Fully Halogenated Chlorofluorocarbon Voluntary Phaseout Program. 12 April 1988.

More information on blowing agents is available at:
Polystyrene Packaging Council ( www.polystyrene.org/polystyrene_facts/facts.html )