Researchers from the University of Alabama at Birmingham and Johns Hopkins University, brought in by Amoco Corp. (now BP Amoco PLC) to study an apparent cluster of brain tumor cases, released an interim report on August 5. A final report will be released following peer review.
Concern was first raised in 1989, when it was discovered that three employees who had worked in the same laboratory at the Amoco Research Center in Naperville, Illinois had developed a rare form of brain cancer called glioma. Three additional cases of glioma were later found in employees who had worked in the same building, as well as at least 13 benign brain tumors in employees across the whole site.
According to the interim report, all six glioma patients worked in the Research Center’s 500 complex, five of them on the same floor of one building. The patients appear to have worked more frequently than the control group with ionizing radiation sources and a solvent called n-hexane. However, the small size of the study and the lack of scientific evidence linking known exposure levels to brain cancer mean researchers cannot rule out mere coincidence.
The investigators conclude that “occupational exposure at the facility may have contributed to the excess of gliomas among 500 building complex employees, but they feel the results fall short of identifying specific agents that led to the illnesses.” They found “no scientific evidence to link any benign intracranial tumors or any other cancers to work at the facility.”
According to BP Amoco spokespersons, the passage of time and subsequent renovations of the buildings make it unlikely that the substance that caused the cancers, if one existed, is still present in the complex or left a trail that will allow it to be discovered.
While the apparent cluster could be nothing more than a tragic coincidence, Amoco has spent millions of dollars investigating possible workplace factors.