Low exposure to benzene linked to changes in blood
WASHINGTON - (AP) -- Blood changes, including a steep decline in diseasefighting white cells, have been found in workers persistently exposed to low levels of benzene, a common industrial chemical known to pose a leukemia risk at high concentrations.
Researchers reported Thursday in the journal Science that workers in a Chinese shoe factory exposed to less than one part per million of benzene experienced a significant decline of white cells and found their blood-forming cells were less vigorous than normal.
U.S. occupational guidelines limit benzene exposure to one part per million, but the study found changes in the blood from lower exposure.
''We can't say that this is associated with the future risk of disease,'' said Dr. Nathaniel Rothman, one of two senior authors of the study. ``But it does raise the question of what else is going on in the bone marrow.''
Benzene is one of the most used chemicals in U.S. industry. It is used as a solvent and to make plastics, resins, adhesives and synthetic fibers.