Résumé :
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[BDSP. Notice produite par INIST 3R0xB3Qc. Diffusion soumise à autorisation]. In 1997, the International Agency for Research on Cancer determined that crystalline silica was a human carcinogen but noted inconsistencies in the epidemiology. There are few exposure-response analyses. The authors examined lung cancer mortality among 4,626 industrial sand workers, estimating exposure via a job-exposure matrix based on 4,269 industrial hygiene samples collected in 1974-1995. The average length of employment was 9 years, and estimated average exposure was 0.05 mg/m3 (the National Institute of Occupational Safety and Health Recommended Exposure Limit). Results confirmed excess mortality from silicosis/pneumoconioses (standardized mortality ratio=18.2,95% confidence interval : 10.6,29.1 ; 17 deaths). The lung cancer standardized mortality ratio was 1.60 (95% confidence interval : 1.31,1.93 ; 109 deaths). Limited data suggested that smoking might account for 10-20% of the lung cancer excess. Exposure-response analyses by quartile of cumulative exposure (15-year lag) yielded standardized rate ratios of 1.00,0.78,1.51, and 1.57 (p for trend=0.07). Nested case-control analyses after exclusion of short-term workers, who had high overall morality, yielded odds ratios by quartile of cumulative exposure (15-year lag) of 1.00,1.35,1.63, and 2.00 (p for trend=0.08) and odds ratios by quartile of average exposure of 1.00,0.92,1.44, and 2.26 (p=0.005). (...)
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