National trends in silicosis mortality in the United States, 1981-2004

Background This article describes trends in mortality with silicosis and identifies industries and occupations with elevated silicosis mortality. Methods A total of 6,326 deaths with silicosis for 1981-2004 were analyzed for trends and association with occupation and industry. Annual mortality rates were age-adjusted to the U.S. Year 2000 population. A linear regression model was used for analyzing mortality trends. Proportionate mortality ratios (PMRs) were based on 1,440 deaths with information on usual industry and occupation. Results Overall age-adjusted mortality rates per million declined from 2.4 in 1981 to 0.7 in 2004. Industries having significantly elevated PMRs for silicosis included mining and quarrying. Occupations with elevated PMRs included those associated with metal and mineral processing. Conclusions The results suggest that considerable progress has been made towards elimination of this preventable disease. However, about 30 silicosis deaths per year have been recorded since 1995 among those of working age, warranting continued efforts to effectively limit workplace exposures.