Smarter Living: Chemical Index
An industrial chemical used to make plastics, styrene is harmful to the nervous system and a possible carcinogen.
What Is It?
Styrene is a chemical used to make several kinds of plastic. The ubiquitous foam coffee cup, found in office break rooms around the country, is made from polystyrene. Less known is plastic spoons and other cutlery, whether white or clear, are usually made of polystyrene. You can tell if your plastics are polystyrene by looking for a number 6 in the chasing-arrows triangle.
Another common plastic made with styrene is ABS (acrylonitrile-butadiene-styrene), used in bike helmets and other hard plastic sports equipment. A number of other lesser known plastics contain styrene.
Styrene may be added to food as a flavoring and has been detected in prepacked cookies, cakes, and doughnuts in a US Food and Drug Administration Diet Study of foods tested between September 1991 and October 2003. Styrene is also used in take-out containers and other food wrappers, as well as packaging materials, carpet backing, fiberglass, rubber, and automobile and boat parts. Styrene has a sweet smell that is noticeable when you use certain adhesives and resins.
The chemical is formed during burning, so it is found in cigarettes and car exhaust. It is also released when you use a photocopier. A small amount is formed through natural processes.
Styrene in the air can irritate the eyes and lungs. High levels of the chemical (1,000 times greater than what is found in outdoor air) can cause vision and hearing loss, impaired memory and concentration, problems with balance, and delayed reaction times among workers in plastics manufacturing. Long-term use of styrene, as in the workplace, may cause oxygen-carrying red blood cells to be smaller and fewer in number. In animal studies the chemical has been shown to damage the lining of the nose as well as the liver, kidneys, and spleen.
Several studies of people who work in styrene manufacturing have found that these individuals have an increased risk of leukemia and lymphoma. Studies in animals have been mixed, with some finding that rats developed tumors and others finding no effect. The International Agency for Research on Cancer (IARC) classified styrene as a “possible human carcinogen,” stating that the evidence in humans was inadequate to make a more certain conclusion. The National Toxicology Program has stated that styrene is "reasonably anticipated" to cause cancer in humans.
Styrene has also been studied for any harm to unborn children of women working in the plastics industry. Some studies found that women were at higher risk of miscarriage but other studies found no increased risk.
Once released into the air, styrene can react with sunlight and produce smog.
Styrene has been dumped in lakes and rivers, vented into the air, and buried in drums underground. Of the nearly 20 million pounds of waste styrene sent into the environment each year, about 17.8 million pounds goes into the air and 1.7 million flows into surface waters, according to the EPA.
People who work in or live near a styrene plastics manufacturing plant have the highest levels of exposure to styrene. Another way that people are exposed to styrene is by breathing the chemical while using glues or resins when doing repairs on their home, car, or boat. Breathing car exhaust, cigarette smoke, and fumes from photocopiers can also expose you to styrene. A small number of people may live in an area with contaminated drinking water. You may eat small amounts of styrene in processed or prepackaged foods.
Reduce your styrene exposure by not smoking, by avoiding idling your vehicle, and by using photocopiers in a well-ventilated area. When buying a new copier, look for ones that meet standards set by Green Guard or Blue Angel.
When purchasing new furnishings, air them outdoors to release any styrene or other volatile fumes before bringing them into your living space, and make sure the indoor space is well-ventilated.
For snacks and treats, choose fruits and other whole foods rather than prepackaged foods, which tend to be less healthy not only because they may contain additives such as styrene but also because they are high in fat, sugar, and salt content. Styrene in packaging can enter food, so avoid storing food in polystyrene foam or clear plastic clamshell containers marked with a number 6.
Help reduce the amount of styrene created and dumped into the environment by choosing reusable food serving items instead of polystyrene coffee cups and disposable picnicware. For example, inexpensive stainless steel forks, spoons, and knives can be used for years, saving you money and shopping time every time you host a party.
Polystyrene foam coffee cups and take-out containers are clogging landfills and ending up in the ocean where foam pieces are swallowed by sea birds and marine animals. Do your part to reduce this waste by avoiding purchasing food in polystyrene containers.
Agency for Toxic Substances and Disease Registry (ATSDR) Public Health Statement for Styrene
Learn more about styrene emissions from photocopiers from the California EPA.
last revised 12/27/2011