Article

Hematotoxicity in workers exposed to low levels of benzene.

Division of Cancer Epidemiology and Genetics, National Cancer Institute (NCI), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Bethesda, MD 20892, USA.
Science (impact factor: 31.2). 01/2005; 306(5702):1774-6. DOI:10.1126/science.1102443 pp.1774-6
Source: PubMed

ABSTRACT Benzene is known to have toxic effects on the blood and bone marrow, but its impact at levels below the U.S. occupational standard of 1 part per million (ppm) remains uncertain. In a study of 250 workers exposed to benzene, white blood cell and platelet counts were significantly lower than in 140 controls, even for exposure below 1 ppm in air. Progenitor cell colony formation significantly declined with increasing benzene exposure and was more sensitive to the effects of benzene than was the number of mature blood cells. Two genetic variants in key metabolizing enzymes, myeloperoxidase and NAD(P)H:quinone oxidoreductase, influenced susceptibility to benzene hematotoxicity. Thus, hematotoxicity from exposure to benzene occurred at air levels of 1 ppm or less and may be particularly evident among genetically susceptible subpopulations.

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Keywords

1 part
 
air levels
 
Benzene
 
benzene exposure
 
benzene hematotoxicity
 
bone marrow
 
genetic variants
 
genetically susceptible subpopulations
 
key metabolizing enzymes
 
mature blood cells
 
Progenitor cell colony formation
 
susceptibility
 
toxic effects
 
U.S. occupational standard
 
uncertain
 
white blood cell