The statement notes that there have been recent announcements on the development and commercialisation of styrene-free unsaturated polyester (UP) resins for use in specific applications (see DSM launches range of styrene-free resins).

The European UP Resin Sector Group says that such technologies could deliver benefits in the future and that the Group member companies (Ashland, CCP Composites, Reichhold and Scott Bader) have not only been committed to the support and development of styrene-based resins, but equally to the development of alternatives resins. However, as these alternatives are still in the early stages of the development, styrene-based resins will continue to be the most reliable substance on the market for unsaturated polyester resin applications.

The statement says that styrene-based resins will also continue to be the most cost-competitive choice for the time being, and notes that styrene monomer is widely available across the globe from long term manufacturers.

The statement continues to say that styrene-free resins lack the versatility of styrene-containing resins and are not available for all applications. Current alternatives to styrene in unsaturated polyester resins are less versatile and less well-studied from a regulatory perspective. The Sector Group concludes that at this stage there is no alternative solution that can match the universal performance of styrene.

The safety of styrene

The European UP Resin Sector Group states that In 2007, the European Union (EU) risk assessment of styrene concluded that it is safe for both the environment and for consumers. The Sector Group notes it is committed to developing best practices and has produced safe use guidelines for handling unsaturated polyester. In addition, group members are active in developing effective closed-mould systems that further protect workers’ health.

The statement notes that in June 2011, the US Department of Health and Human Services (HSS) included styrene monomer in the National Toxicology Program’s (NTP) 12th Report on Carcinogens (RoC) as a substance that is “reasonably anticipated to be a human carcinogen”. This conclusion by the NTP is diametrically opposed to the European-wide assessment that styrene does not pose a concern for human carcinogenicity. The US industry association, Styrene Information and Research Center (SIRC), is actively contesting the listing by the NTP.

The full statement is available on the European UP Resin Sector Group website and attached as a download to this article.