Calibrating a population-based job-exposure matrix using inspection measurements to estimate historical occupational exposure to lead for a population-based cohort in Shanghai, China

• Published in: Journal of exposure science & environmental epidemiology Vol. 24; no. 1; pp. 9 - 16
• Main Authors: Koh, Dong-Hee, Bhatti, Parveen, Coble, Joseph B, Stewart, Patricia A, Lu, Wei, Shu, Xiao-Ou, Ji, Bu-Tian, Xue, Shouzheng, Locke, Sarah J, Portengen, Lutzen, Yang, Gong, Chow, Wong-Ho, Gao, Yu-Tang, Rothman, Nathaniel, Vermeulen, Roel, Friesen, Melissa C
• Format: Journal Article
• Language: English
• Published: United States Nature Publishing Group 01.01.2014
• Subjects: Adult; Aged; Air Pollutants, Occupational - analysis; Calibration; Cancer; Carcinogenicity; Carcinogens; China; Cohort Studies; Dust; Dust - analysis; Electronic equipment; Epidemiology; Estimates; Exposure; Female; Health risks; Humans; Industrial development; Industry; Inspection; Lead - analysis; Lead poisoning; Middle Aged; Occupational exposure; Occupational Exposure - analysis; Occupational health; Occupations; Retrospective Studies; China; China, People's Rep
• ISSN: 1559-0631; 1559-064X
• DOI: 10.1038/jes.2012.86

The epidemiologic evidence for the carcinogenicity of lead is inconsistent and requires improved exposure assessment to estimate risk. We evaluated historical occupational lead exposure for a population-based cohort of women (n=74,942) by calibrating a job-exposure matrix (JEM) with lead fume (n=20,084) and lead dust (n=5383) measurements collected over four decades in Shanghai, China. Using mixed-effect models, we calibrated intensity JEM ratings to the measurements using fixed-effects terms for year and JEM rating. We developed job/industry-specific estimates from the random-effects terms for job and industry. The model estimates were applied to subjects' jobs when the JEM probability rating was high for either job or industry; remaining jobs were considered unexposed. The models predicted that exposure increased monotonically with JEM intensity rating and decreased 20-50-fold over time. The cumulative calibrated JEM estimates and job/industry-specific estimates were highly correlated (Pearson correlation=0.79-0.84). Overall, 5% of the person-years and 8% of the women were exposed to lead fume; 2% of the person-years and 4% of the women were exposed to lead dust. The most common lead-exposed jobs were manufacturing electronic equipment. These historical lead estimates should enhance our ability to detect associations between lead exposure and cancer risk in the future epidemiologic analyses.