By Heide Brandes
OKLAHOMA CITY, Sept 1 (Reuters) - The University of Tulsa isworking to clean up what it is calling a minor spill of aradioactive chemical on its research campus and is having 21people who may have been exposed to the cesium-137 undergomedical evaluations, school officials said on Tuesday.
The spill by Tracerco, a subsidiary of British chemicalcompany Johnson Matthey that was contracted by theuniversity, is believed to have occurred last fall but Tracercodid not notify the school about it until Aug. 25, the universitysaid.
Tracerco spilled a small quantity of cesium-137, aradioactive isotope often used in research, in a restrictedbuilding on a campus that houses research equipment, accordingto Steadman Upham, the university's president.
The cesium-137 was being used for research on a jointindustry project managed by the petroleum engineeringdepartment, the university said. The level of radiation from thespill is currently unknown, school officials said.
The university found that 21 people were at risk forexposure and it is having those people evaluated by medicalexperts, the school said.
People routinely are exposed to very small amounts ofcesium-137 in soil and water, but higher levels of exposure canincrease the risk of cancer, according to the U.S. EnvironmentalProtection Agency.
After being notified of the spill, the universityimmediately restricted access to the building and contacted theOklahoma Department of Environmental Quality, which has sinceinspected the site and the surrounding areas, said MonaChamberlin, spokeswoman for the school.
The university said it is working with state officials todraw up a comprehensive plan for the clean up.
Tracerco officials were not immediately available forcomment. (Editing by Jon Herskovitz and Will Dunham)