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FAQsWhat is styrene?Do I come in contact with styrene?Is styrene harmful to my health?What about the scent of styrene around manufacturing plants?What happens to styrene released into the environment?What about the health of workers exposed to styrene?Is there a concern about cancer risk?Are there alternatives for styrene?What is the Styrene Information and Research Center (SIRC)?What is styrene?Styrene is a clear, colorless liquid that is a component of materials used to make thousands of everyday products for home, school, work and play. Products made from styrene add convenience, value and quality to daily life. They range from packaging such as jewel cases that protect CDs and containers that keep yogurt fresh to toys, recreational equipment, and myriad consumer electronics, construction, transportation, medical, health and safety applications. Derived from petroleum and natural gas by-products, styrene helps create thousands of remarkably strong, flexible, and light-weight products that represent a vital part of our health, safety and well-being. Probably the most recognizable material is polystyrene, often encountered as expanded polystyrene foam (EPS). Other styrene-based materials include acrylonitrile-butadiene styrene (ABS), styrene-acrylonitrile (SAN), styrene-butadiene rubber (SBR), and unsaturated polyester resin (UPR), which is better known as fiberglass. To learn more about how styrene’s countless benefits bring peace of mind and quality to life, click here: Styrene Uses and Benefits Brochure. The styrene used in these products is manufactured in petrochemical plants located all around the U.S. and, indeed, around the world. More information can be found under Styrenics and the U.S. Economy. However, styrene also occurs in the environment and is found in many common foods, such as coffee, strawberries and cinnamon. Additional information can be found under Styrene Occurrence in Food. (top) Do I come in contact with styrene?Most people are exposed to styrene every day in tiny amounts that may be present in the air, or that occur in food. These generally are trace amounts, which were difficult to detect until recent technological advances. We also may recognize styrene by its distinctive odor (described by some as sweet) when using certain products such as latexes, paints and polyester resin solutions. Some people confuse styrene, which is a liquid, with polystyrene, which is a solid plastic made from polymerized styrene. Styrene and polystyrene are fundamentally different. Polystyrene is inert and has no smell of styrene. Polystyrene often is used in applications where hygiene is important, such as health care and food-service products. For more information on polystyrene products, visit the Plastics Foodservice Packaging Group (PFPG) homepage. (top) Is styrene harmful to my health?Styrene is not harmful in the very small amounts we sometimes may encounter in air or food. Someone working in an enclosed area with resin solutions containing styrene (patching the surface of a fiberglass boat, for example) may find the odor of styrene causes slight nausea. This goes away with exposure to fresh air, and there is no lasting effect. In an important decision made in 1994 after an exhaustive assessment of styrene’s possible health and environmental effects, the government agencies Health Canada and Environment Canada concluded that styrene is "non-toxic" for regulatory purposes. Health Canada found that styrene "does not constitute a danger to human life and health" and "does not constitute a danger to the environment on which human life depends." A report on a styrene risk assessment by the [PDF]Harvard Center for Risk Analysis also concluded that there are no concerns for the general public, either from environmental or consumer exposures to styrene. Over the last several years, the U.S. Environmental Protection Agency has been conducting a formal review of styrene for its Integrated Risk Information System (IRIS) database. When completed, the findings will provide an assessment of the scientific data on styrene relative to its potential to impact human health or the environment. Styrene and Human Health has additional information concerning styrene. (top) What about the scent of styrene around manufacturing plants?Styrene's distinctive odor can be detected even when styrene is present at extremely low levels. People living near facilities that make or use styrene sometimes may notice a slight scent in the air. If you have concerns about such odors in your neighborhood, you may wish to contact the plant's manager or your local health department. The Harvard Center for Risk Analysis (HCRA) also evaluated the public risk from styrene exposure. Findings were reported in HCRA’s May 2002 Risk in Perspective newsletter. (top) What happens to styrene released into the environment?Extensive research shows that styrene exists only briefly in the environment; it is destroyed rapidly in the air and disappears quickly from soils and surface waters. Studies also have shown that styrene is not likely to occur in drinking water. Additional information can be found under Environmental Fate Research and Ecotoxicity Research. (top) What about the health of workers exposed to styrene?The health of workers in plants making or using styrene has been monitored for many years. Studies looking for long-term health effects related to styrene exposure have examined health records of over 50,000 workers exposed to styrene, going back more than 50 years. These studies have not shown any statistically significant increases in long-term health problems of any kind attributable to styrene exposure in these workers. In the United States, as in most industrialized countries, strict regulations are in place to protect worker health. In 1989, the U.S. Occupational Safety and Health Administration (OSHA) established a safe exposure standard for styrene of 50 parts per million (ppm) over an eight-hour day. Typically, the actual exposure levels in styrene manufacturing plants are 20 to 50 times below this safety level. In years past, before effective monitoring systems were available, worker exposure to styrene (as well as other materials) often was greater than current exposure levels. In July 1992, a U.S. appeals court voided the 1989 OSHA rulemaking, and the pre-1989 level of 100 ppm was reinstated as the enforceable limit. However, the Styrene Information and Research Center (SIRC) encouraged its member companies to continue to comply with the 50-ppm exposure limit. Additionally, several states independently adopted and enforce a 50-ppm exposure limit. In February 1996, OSHA endorsed a styrene industry proposal to voluntarily meet a 50 ppm exposure level. Industry’s ongoing voluntary compliance can help OSHA avoid the need for another costly and time-consuming review of styrene. The Harvard Center for Risk Analysis (HCRA) also evaluated the risk to workers from styrene exposure. HCRA’s Risk in Perspective newsletter addresses this topic. (top) Is there a concern about cancer risk?SIRC has invested many years and some $14 million in funding to develop the most thorough and accurate information about possible cancer effects resulting from styrene exposure. The results of extensive health studies of workers in styrene-related industries collectively show that exposure to styrene does not increase the risk of developing cancer or any other health effect. Results of a two-year styrene inhalation study in rats exposed to high concentrations of styrene, completed in 1996, also showed no increased incidence of cancer. Additional information can be found under Carcinogenicity Research. From a regulatory viewpoint, in 1989 OSHA and the U.S. Centers for Disease Control and Prevention’s National Institute for Occupational Safety and Health (NIOSH) reviewed the health data on styrene and concluded that styrene does not pose any cancer risk. An international panel of experts from the 12-nation European Community reached the same conclusion in 1988. Canada decided in 1994 that styrene posed no carcinogenic risk. A draft 1996 risk assessment of styrene by the Health & Safety Executive of the United Kingdom also concluded that styrene does not pose a carcinogenic threat. In 1987, the International Agency for Research on Cancer (IARC) upgraded styrene's classification to a "possible" human carcinogen. Many scientists have disputed this action because it was not based on new cancer data, but resulted from changes in the criteria for IARC classifications. In subsequent reviews in 1994 and 2002, IARC chose to maintain its classification for styrene. SIRC believes that the significant amount of available scientific data indicates this classification is not warranted, and continues to address IARC's decision. It is important to note that IARC's charter stresses that their classifications are for hazard identification only - not to determine the risk of a given substance - and should not be used for regulatory purposes. (top) Are there alternatives for styrene?No other material can provide the same performance characteristics, quality and cost-effectiveness of styrene. Styrene is so widely used because it has been substituted over the years for other materials to create better products. For example, boats made from styrenic material are more structurally sound, packaging is more sanitary and less costly, automobiles have lighter components making them more fuel-efficient, and building insulation quality has greatly improved, helping to cut energy costs. To learn more about how styrene’s countless benefits bring peace of mind and quality to life, click here: [PDF] Styrene Uses and Benefits Brochure. (top) What is the Styrene Information and Research Center (SIRC)?SIRC is a non-profit organization established in 1987 by companies involved in the manufacture or use of styrene. SIRC's mission is to evaluate existing data on potential health effects of styrene, to develop additional data where it is needed, and to communicate the results of all these findings when and where appropriate. SIRC has gained worldwide recognition as a source for information on styrene, thus helping to ensure that employee and public health is fully protected, and that regulatory and legislative decisions are based on sound science. (top) |
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