In the largest study of its kind, conducted by Richard Clapp of the Boston University School of Public Health, researchers studied 30,000 deaths of workers who had been employed at IBM factories in the U.S. As reported in Science Daily on Oct. 19, the study concluded that there was increased mortality due to several types of cancer, especially in manufacturing workers and workers at particular plants in California, Minnesota, New York and Vermont. Most notably, there was an excess of deaths due to cancer of the brain and central nervous system. Kidney cancer, non-Hodgkin's lymphoma and breast cancer were also found in excess in some groups of workers.
The study looked at workers who had been employed at least five years between 1969 and 2001. The data were obtained from IBM as part of a California lawsuit against IBM.
It was not possible to link these deaths to specific chemicals or other exposures in the workplace because the information necessary to do this was not available.
The study confirms a small mortality study of just three IBM plants published a year ago by company consultants, which also showed increased deaths due to brain and central nervous system cancer.