RT Journal Article
SR Electronic
T1 Benzene exposure and risk of benzene poisoning in Chinese workers
JF Occupational and Environmental Medicine
JO Occup Environ Med
FD BMJ Publishing Group Ltd
SP oemed-2021-108155
DO 10.1136/oemed-2021-108155
A1 Roel Vermeulen
A1 Lützen Portengen
A1 Guilan Li
A1 Ethel S Gilbert
A1 Graça M Dores
A1 Bu-Tian Ji
A1 Richard Hayes
A1 Sognian Yin
A1 Nathaniel Rothman
A1 Martha S Linet
A1 Qing Lan
A1 ,
YR 2022
UL http://oem.bmj.com/content/early/2022/03/09/oemed-2021-108155.abstract
AB Objectives Benzene 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.Methods In 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.Results There 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.Conclusions Our 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.Data are available on reasonable request.