Silica, silicosis, and cancer: controversy in occupational medicine. Goldsmith DF, Winn DM, Shy CM, eds. New York: Praeger, 1986 Jan; :3-9
Maps describing cause specific mortality rates for silicosis were compared with maps of locations with potential silica (14808607) hazards. The National Occupational Hazard Survey (NOHS) conducted by NIOSH during the years 1972 to 1974 was used as a data base for demographic information concerning potential worker exposure to silica. Mining, quarrying, and agricultural industries were not surveyed in the initial NOHS study, so the Dun and Bradstreet file, which contains descriptors such as standard industrial code, county, and size of workforce was linked to this data base. This information was used to construct maps depicting geographic location of workers and worksites, by county, where there was a high probability of exposure to silica. These maps were juxtaposed with mortality maps, by county, of deaths among white males from 1968 to 1978 due to silicosis and lung cancer. As a general trend, clusters of deaths from silicosis and lung cancer emerged in coal mining areas. One county, used by the authors to illustrate the hypothesis generating capability of their approach, was in the highest category in silicosis and lung cancer deaths and also had a high frequency occupational exposure to sand and/or free silica from gray iron casting, plaster and drywall, ready mixed concrete, pottery products, roofing, sheet metal, and steel foundries. The authors conclude that this approach may be useful in identifying counties in which to conduct mortality based case/control studies.