Mesothelioma surveillance to locate sources of exposure to asbestos.

To determine whether there were previously unrecognized sources of asbestos exposure in British Columbia, incident mesothelioma cases (n = 51) and population-based controls (n = 154) were interviewed about their occupational histories and asbestos exposures. The following occupations were at elevated risk: sheet metal workers (OR = 9.6, 95% CI: 1.5-106), plumbers and pipefitters (OR = 8.3, 95% CI: 1.5-86), shipbuilding workers (OR = 5.0, 95% CI: 1.2-23), painters (OR = 4.5, 95% CI: 1.0-24), welders (OR = 3.9, 95% CI: 0.8-22), gardeners (OR = 3.9, 95% CI: 0.8-22), bricklayers (OR = 3.5, 95% CI: 0.9-14), miners (OR = 3.4, 95% CI: 0.9-13), machinists (OR = 3.2, 95% CI: 1.0-11), construction foremen (OR = 3.1, 95% CI: 0.9-11), and electricians (OR = 3.0, 95% CI: 0.8-12). In a reanalysis excluding subjects who worked in occupations or processes considered strongly a priori at risk, three groups remained of interest: non-asbestos miners (OR = 9.6, 95% CI: 1.8-53), bricklayers (OR = 5.4, 95% CI: 1.0-28), and construction labourers (OR = 2.8, 95% CI: 0.7-10.6).