WASHINGTON -- A new study of nearly 16,000 workers exposed to styrene in the workplace shows no credible evidence that styrene exposures increase cancer risks, the Styrene Information and Research Council, a sponsor of the report, said.

The study, "Cancer Mortality of Workers Exposed to Styrene in the U.S. Reinforced Plastics and Composite Industry," was published in the March 2013 issue of the scientific journal Epidemiology. The research council said it supported the research but did not contribute in any way to its content.

The authors of the study examined mortality rates associated with cumulative exposures, durations of exposure, peak exposures, average exposures and times since first exposures to styrene, based on 60 years of epidemiology data, the SIRC said.

This is the second study so far this year that finds no connection between styrene exposure and cancer. Gradient, a Cambridge, Mass.-based environmental and risk science consulting firm working for SIRC, issued an analysis of previous existing styrene studies, also finding no correlation between styrene exposure and increased fatality from any type of cancer.

Since June 2011, SIRC and its members have been fighting the inclusion of styrene as an anticipated human carcinogen in the National Toxicology Program's 12th Report on Carcinogens.

NTP ruling was based on a biased and faulty review of existing data, and the European Union declined to list styrene as a carcinogen after reviewing the same evidence, SIRC said.