Background Ambient particulate air pollution is associated with cardiovascular disease. The link between cardiovascular disease and occupational particle exposure is however less clear.

Aim To investigate the risk of myocardial infarction from occupational exposure to particles.

Methods This community-based case-control study includes fatal and non-fatal cases of first-time myocardial infarction. The study base comprised all Swedish citizens 45–70 years of age, living in Stockholm County 1992–94, and free of previous myocardial infarction. Controls were selected from the population to match the demographic characteristics of the cases. The response rate for cases and controls was 81% and 75%, respectively. In total, 914 male and 367 female non-fatal cases and 1491 male and 716 female controls were included in the analyses. Occupational exposure was assessed using a Job-Exposure Matrix including 15 agents forming four particle groups; organic, inorganic, combustion particles, and welding fumes. Relative risk estimates were adjusted for age, gender, hospital catchment area, tobacco and alcohol use and the metabolic syndrome (including hypertension, overweight, and diabetes mellitus).

Results We found a significantly increased risk for myocardial infarction in men in the highest quartile of cumulative exposure to organic particles (OR 1.37; 95% CI: 1.03–1.81), and to inorganic particles (OR 1.52; 1.17–1.98). Among women a corresponding increased risk of myocardial infarction was found in the highest quartile of cumulative exposure to organic particles (OR 1.90; 1.04–3.47).

Conclusions Myocardial infarction was increased in men with occupational exposure to organic and inorganic particles. For women the results was less clear due to few cases and few women in exposed jobs. We found no dose-response relationship.