Abstract
ObjectivesBenzene is a known haematoxin and leukemogen that can cause benzene poisoning (BP), that is, a persistent reduction in white cell counts that is strongly associated with increased risk of lymphohaematopoietic malignancies. Data are needed on the exposure–response, particularly at low doses and susceptible populations for clinical and regulatory purposes.MethodsIn a case-cohort study among 110 631 Chinese workers first employed 1949–1987 and followed up during 1972–1999, we evaluated BP risk according to benzene exposure level and investigated risk modification by subject (sex, attained age) and exposure-related factors (latency, exposure windows, age at first benzene exposure, coexposure to toluene) using excess relative risk and excess absolute risk models.ResultsThere were 538 BP cases and 909 benzene-exposed referents. The exposure metric with best model fit was cumulative benzene exposure during a 5-year risk window, followed by a 9-month lag period before BP diagnosis. Estimated excess absolute risk of BP at age 60 increased from 0.5% for subjects in the lowest benzene exposure category (>0 to 10 ppm-years) to 5.0% for those in the highest category (>100 ppm-years) compared with unexposed subjects. Increased risks were apparent at low cumulative exposure levels and for workers who were first exposed at <30 years of age.ConclusionsOur data show a clear association between benzene exposure and BP, beginning at low cumulative benzene exposure levels with no threshold, and with higher risks for workers exposed at younger ages. These findings are important because BP has been linked to a strongly increased development of lymphohaematopoietic malignancies.
Funder
National Cancer Institute
Subject
Public Health, Environmental and Occupational Health
Reference22 articles.
1. Carcinogenicity of benzene
2. Benzene poisoning, a risk factor for hematological malignancy, is associated with the NQO1 609C-->T mutation and rapid fractional excretion of chlorzoxazone;Rothman;Cancer Res,1997
3. Indirect validation of benzene exposure assessment by association with benzene poisoning;Dosemeci;Environ Health Perspect,1996
4. Chronic exposure to benzene results in a unique form of dysplasia
5. Haematological effects of chronic benzene poisoning in 217 workers;Aksoy;Br J Ind Med,1971
Cited by
7 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献