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NTP — Styrene: Request for Correction (RFC)

June 10, 2003

Dr. C. W. Jameson 
National Toxicology Program Report on Carcinogens MD EC-14 
P.O. Box 12233 
Research Triangle Park, NC 27709 

Re:Request for Technical Corrections to Press Release and Factsheet Concerning the Tenth Report on Carcinogens-Styrene Oxide

Dear Dr. Jameson:

The Styrene Information and Research Center, Inc. (SIRC) requests that the National Toxicology Program (NTP) make an important technical correction to the press release and factsheet, currently on NTP's website, announcing the publication of the tenth edition of the National Toxicology Program's (NTP's) Report on Carcinogens (ROC). These website materials contain incorrect information concerning the use of styrene-7,8-oxide (SO).1

The entry for styrene oxide in the Tenth Report carefully notes potential worker exposure and cites researchers who "hypothesized that SO formed either by breakdown of polymeric styrene peroxide radicals resulting from the copolymerization of styrene and oxygen, by epoxidation of the styrene monomer, or by reaction of styrene with volatile organic peroxides used in curing reinforced plastics."

This is consistent with information that SIRC previously provided to NTP confirming that styrene oxide is not used commercially in the United States or as a raw material in the manufacture of reinforced plastics. But, both the factsheet and press release incorrectly state that: "Styrene7,8-oxide is used in producing reinforced plastics and as a chemical intermediate for cosmetics, surface coatings, agricultural and biological chemicals." 2

Given this discrepancy, SIRC requests that the NTP delete this sentence from the factsheet and press release. In the alternative, NTP could state that "Styrene oxide may be present in reinforced plastic operations."

This request is not a challenge to NTP's listing or toxicological classification of styrene oxide. Rather SIRC's request is submitted pursuant to the National Institute of Health (NIH) Guidelines for Ensuring the Quality of Information Disseminated to the Public, to obtain correction of information disseminated by the NIH or its components that do not comply with information guidelines promulgated by the NIH, the Department of Health and Human Services, or the Office of Management and Budget.3

In addition, we are certain that NTP can understand the implications for the reinforced plastics industry if these NTP materials mislead people into believing that the industry is intentionally utilizing a substance that NTP has classified as reasonably anticipated to be a carcinogen.

Should you have any questions on these technical corrections, please do not hesitate to contact me. Naturally, if NTP has information that styrene oxide is used commercially in the United States, we would very much appreciate the citation for or source of that information.


John O. Snyder
Excutive Director

1The Styrene Information and Research Center (SIRC) was formed in 1987 as the principal focal point for public information and research on the chemical styrene. SIRC also serves as a liaison between industry, federal and state government, and international agencies on health-related issues involving styrene. SIRC is a non-profit organization consisting of over 20 voting member companies involved in the manufacturing or processing of styrene, and some 30 associate member companies that fabricate styrene-based products. Collectively, SIRC's membership represents approximately 95% of the North American styrene industry.

2See http://ntp-server.niehs.nih.govf/NewHomeRoc/10th_RoCFacts.pdf, and, respectively.

Last Revised:  August, 2004