Recent trends of age-specific pneumoconiosis mortality rates in the United States, 1985-1996: coal workers' pneumoconiosis, asbestosis, and silicosis.

The authors examined the temporal trends of age-specific pneumoconiosis mortality from coal worker's pneumoconiosis (CWP), asbestosis, and silicosis in the United States in 1985-1996. Mortality data were derived from the National Center for Health Statistics multiple causes of death files for the period. Age-specific mortality rates were computed for three age groups (15-44, 45-64, and > or = 65 years) among decedents with mention of CWP, asbestosis, or silicosis. Linear regression analysis was performed to examine the annual changes in age-specific mortality rates, by age group, with each specific condition. The CWP mortality rates declined significantly (p = 0.0001) in the groups 45 years old and older, but not in the age group 15-44. Asbestosis mortality rates declined significantly (p = 0.005) for the age group 45-64, while increasing (p = 0.0001) for those aged 65 years and older. However, in the younger age group 15-44, the rates showed no significant trend. Silicosis mortality rates declined significantly (p = 0.0001) for all groups. The continued occurrence of deaths from CWP, asbestosis, and silicosis among young adults may be the result of high levels of exposure to occupational risks. These results suggest that pneumoconiosis surveillance may help to evaluate the temporal pneumoconiosis mortality patterns in the United States.

Surveillance of respirable crystalline silica dust using OSHA compliance data (1979-1995).

BACKGROUND: The objective of this work was to estimate the percentage of workers by industry that are exposed to defined concentrations of respirable crystalline silica dust. METHODS: An algorithm was used to estimate the percentage of total workers exposed to crystalline silica in 1993 at concentrations of at least 1, 2, 5, and 10 times the National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) of 0.05 mg/m3. Respirable crystalline silica air sampling data from regulatory compliance inspections performed by the Occupational Safety and Health Administration (OSHA), for the years 1979-1995, and recorded in the Integrated Management Information System (IMIS) were used to estimate exposures. Therefore, this work does not include industries such as mining and agriculture that are not covered by OSHA. The estimates are stratified by Standard Industrial Classification (SIC) codes. RESULTS: This work found that some of the highest respirable crystalline silica dust concentrations occurred in construction (masonry, heavy construction, and painting), iron and steel foundries (casting), and in metal services (sandblasting, grinding, or buffing of metal parts). It was found that 1.8% (13,800 workers) of the workers in SIC 174--Masonry, Stonework, Tile Setting, and Plastering--were exposed to at least 10 times the NIOSH REL. For SIC 162--Heavy Construction, Except Highway and Street Construction--this number is 1.3% (6,300 workers). SIC 172--Painting and Paper Hanging--which includes construction workers involved in sandblasting was found to have 1.9% (3,000 workers) exposed to at least 10 times the NIOSH REL. The industry that was found to have the highest percentage of workers (6%) exposed to at least the NIOSH REL was the cut stone and stone products industry. CONCLUSION: Not enough is being done to control exposure to respirable crystalline silica. Engineering controls should be instituted in the industries indicated by this work.

Surveillance data on US coal miners' pneumoconiosis, 1970 to 1986.

OBJECTIVES: Statistics on prevalence of pneumoconiosis among working underground coal miners from data collected as part of a large national radiographic surveillance program between 1970 and 1986 are presented. The main intent was to examine the time-related trend in prevalence over this period, which coincides with historically low dust levels mandated by federal act. METHODS: Tenure-specific prevalence rates and summary statistics derived from them for four consecutive time intervals within the 16-year period were calculated and compared. RESULTS: The results indicate a reduction in pneumoconiosis over the life of the program. This trend is similar to that seen in epidemiologic studies undertaken concurrently. CONCLUSIONS: Although low participation in the surveillance program and other problems complicate the findings, it appears that reductions in dust exposure mandated by federal act in 1969 have led to lower prevalence of pneumoconiosis among underground coal miners.

Silicosis in silica flour workers.

In July 1979, the health of 86 current and ex-workers at 2 silica mining and milling operations in southern Illinois was examined using a respiratory questionnaire, spirometry, and chest radiographs. None of 25 current workers with less than 1 yr of exposure to silica dust had radiographic evidence of silicosis. For 61 current workers and ex-workers with 1 or more yr of exposure, chest radiographs showed 16 (26%) with simple silicosis and 7 (11%) with progressive massive fibrosis. Of these 23, 8 with simple silicosis and 3 with progressive massive fibrosis began work after the first Mine Safety and Health Administration inspection in 1973. These data and a review of federal dust inspection results between 1973 and 1979 showed that these cases of silicosis could have been prevented by effecting compliance with the existing dust standard.