Rohm and Haas says an 18-month study it conducted reveals no statistically significant links between an unusually high instance of brain tumors among workers at its Spring House, Pa., research campus and employees' exposure to chemicals on the job.
The company conducted an epidemiological case-control study of the 12 malignant brain cancers and three benign tumors reported among approximately 6,000 employees who worked there over the past 40 years--a cancer rate significantly higher than that of the general population. A team of 22 experts, including physicians, industrial hygienists, and chemists, reviewed employment and medical records. The team studied 20,000 workplace chemicals.
"It is my belief that, based on the study findings and review of the current health and safety practices, Spring House is a safe place to work," says the team's leader, Arvind V. Carpenter, director of epidemiology and sustainable development at Rohm and Haas.
Epidemiologists and neuro-oncologists caution, however, that although certain chemicals have been associated with tumor growth, studies such as Rohm and Haas's are generally inconclusive, given the variety of brain tumors that exist and the incomplete data on the health effects of many chemicals.
"It's difficult with that number of tumors over so many years to say with certainty" whether workplace exposure caused the tumors, says Henry S. Friedman, an oncologist and codirector of the Brain Tumor Center at Duke University.
Friedman has not read the report, which Rohm and Haas says will be published in a peer-reviewed journal this year.-