Chemicals in Styrofoam

The Styrofoam cup you drank your coffee from this morning is one part of a health and environmental debate. The American Chemicals Council's fact sheet makes Styrofoam sound as harmless as green tea, but many environmentalists strongly disagree. The Environmental Protection Agency's fact sheet states that the presence of the harmful chemical styrene in some food products is "due to monomer leaching from polystyrene containers." The FDA, meanwhile, has tested Styrofoam foodservice products and found them safe for use by consumers. Whichever side of the argument is more convincing to you, it is helpful to know what the chemical makeup of Styrofoam is.

Benzene

• One of the principal ingredients in Styrofoam is benzene. Long-term exposure to benzene can cause bone marrow damage and leukemia, and it is listed as a cancer-causing substance. There is no evidence that the use of Styrofoam foodservice products exposes the user to benzene; however, workers can be exposed during the manufacture of Styrofoam. According to Resource 4 Leukemia, even minute exposure to benzene for long periods of time produces serious health problems.

Styrene

• Egg shells from polystyrene cartons have been found to contain styrene.

  According to a 2007 article in the Journal of Environmental Science, hot water from Styrofoam cups was found to be contaminated with styrene. The article went on to say that temperature played a major role in the leaching of the styrene from the Styrofoam. Short-term exposure to styrene can cause gastrointestinal problems and eye irritation. Long-term exposure can harm the central nervous system, and there is a possible link between styrene and reproductive system problems. Some evidence suggests it can also cause leukemia, but it is not currently listed as a cancer-causing agent.

Ethylene

• The EPA states that ethylene is extremely toxic to humans. Neither Styrofoam nor polystyrene is listed as a possible source of ethylene exposure, but emissions from production facilities are. More work is left to be done on the effects of long-term exposure to humans, but studies of animal exposure to ethylene suggest that it attacks the kidneys, liver and testes.

CFCs and HCFCs

• HCFCs are less harmful to the ozone than CFCs.

  Although Styrofoam contains neither chlorofluorocarbons (CFCs) nor hydrochlorofluorocarbons (HCFCs), HCFCs are part of the discussion of Styrofoam's risks and benefits because they are used in the manufacturing process. Ozone-damaging CFCs are no longer used in the Styrofoam manufacturing, but they have been replaced with HCFC-22. HCFC-22 is also a greenhouse gas, though much less harmful to the ozone layer than CFCs.