Objectives Exposure to silica dust is a health hazard in the ceramic industry. The Swedish porcelain factory Gustavsberg started production in 1827, and have since 1971 performed occupational measurements of respirable crystalline silica dust (RCS). We have studied mortality and incidence of acute myocardial infarction (AMI) among workers at the factory.

Methods Exposure data from 436 personal measurements of RCS and respirable dust from 1971–2006 were processed and annual average of exposure levels were calculated. Exposure before 1971 was estimated. Analyses of mortality included 648 men and 315 women, employed for at least one year at the factory in 1958–2009. Forty three different causes of death were studied. Separate analyses of incidence of first time event of AMI included 358 men and 217 women.

Analyses were performed for all workers and for men and women separately. We also studied the effect of latency, duration and cumulative exposure to RCS and respirable dust.

Results RCS-levels among highly exposed workers were five times higher than the OEL and ten times higher in the early 1970s compared with 2000. Workers exposed to RCS had an increased risk of mortality from respiratory diseases, SMR 1.75 (95% CI 1.22–2.44). The risk was more pronounced in men, SMR 1.86 (1.22–2.70). Among women, mortality from diseases of the circulatory system was increased, although not statistically significant.

A non-significant increase in the incidence of AMI was also observed, with slightly higher point estimates for women than for men. No dose-response relationship was observed in any analysis. We observed eight cases of silicosis, and seven appeared with more than 30 years latency.

Conclusions The RCS-levels at the porcelain factory were well above the OEL in the 1970s. We found an increased mortality from respiratory diseases which can be attributed to the harmful effects of RCS on the lung.