The Contribution of Benzene to Smoking-Induced Leukemia

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Mark R. Schulz, Assistant Professor (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: Cigarette smoking is associated with an increased risk of leukemia; benzene, an established leukemogen, is present in cigarette smoke. By combining epidemiologic data on the health effects of smoking with risk assessment techniques for low-dose extrapolation, we assessed the proportion of smoking-induced total leukemia and acute myeloid leukemia (AML) attributable to the benzene in cigarette smoke. We fit both linear and quadratic models to data from two benzene-exposed occupational cohorts to estimate the leukemogenic potency of benzene. Using multiple-decrement life tables, we calculated lifetime risks of total leukemia and AML deaths for never, light, and heavy smokers. We repeated these calculations, removing the effect of benzene in cigarettes based on the estimated potencies. From these life tables we determined smoking-attributable risks and benzene attributable risks. The ratio of the latter to the former constitutes the proportion of smoking induced cases attributable to benzene. Based on linear potency models, the benzene in cigarette smoke contributed from 8 to 48% of smoking-induced total leukemia deaths [95% upper confidence limit (UCL), 20-66%], and from 12 to 58% of smoking-induced AML deaths (95% UCL, 19-121%). The inclusion of a quadratic term yielded results that were comparable; however, potency models with only quadratic terms resulted in much lower attributable fractions-all < 1 %. Thus, benzene is estimated to be responsible for approximately one-tenth to one-half of smoking induced total leukemia mortality and up to three-fifths of smoking-related AML mortality. In contrast to theoretical arguments that linear models substantially overestimate low-dose risk, linear extrapolations from empirical data over a dose range of 10- to 100-fold resulted in plausible predictions.

Additional Information

Publication
Korte, J. E., Hertz-Picciotto, I., Schulz, M. R. , Ball, L. M. , & Duell, E. J. (2000) The contribution of benzene to smoking-induced leukemia. Environmental Health Perspectives 108, 333-339
Language: English
Date: 2000
Keywords
benzene, environmental exposure, epidemiology, leukemia, life tables, occupational exposure, risk assessment, smoking

Email this document to