Mortality and Cancer Experience of Quebec Aluminum Reduction Plant Workers. Part I: The Reduction Plants and Coal Tar Pitch Volatile (CTPV) Exposure Assessment.

摘要

OBJECTIVES:: This paper presents the exposure assessment and job-exposure matrix (JEM) used to estimate coal tar pitch volatile (CTPV) exposure for a study of mortality and cancer incidence in aluminum smelter workers in Quebec, Canada. METHODS:: Historical CTPV exposure was assessed by estimating benzene-soluble material (BSM) and benzo[a]pyrene (B[a]P) levels for combinations of job and time period. Estimates were derived by using several procedures including averaging measurement data, a deterministic mathematical model using process-related correction factors, and expert-based extrapolation. RESULTS:: The JEM comprised 28,910 jobs, covering 7 facilities from 1916 to 1999. Estimated exposures ranged from 0.01 mug/m to 68.08 mug/m (B[a]P) and 0.01 mg/m to 3.64 mg/m (BSM) and were lowest before 1940 and after 1980. CONCLUSION:: This methodology constitutes an improvement compared with methods used for previous studies of the Quebec cohort.