Silicosis in the metal mining industry : a revaluation, 1958-1961.
- United States Public Health Service
- Date:
- [1964]
Licence: Public Domain Mark
Credit: Silicosis in the metal mining industry : a revaluation, 1958-1961. Source: Wellcome Collection.
252/260 page 232
![EFFECTS OF SILICOSIS ON PULMONARY FUNCTION The effects of silicosis on pulmonary function were estimated by developing predicted test results on the basis of men without silicosis and comparing these with test results actually observed in men with silicosis. The 7,817 men included in this analysis have been classified on the basis of X-ray chest findings as follows: No. of _ Cases Group 1: Those whose chest film was coded 0, meaning no X-ray evidence of silicosis or other pneumoconiosis, or 1, meaning suspected or doubtful DHCUMOCONIOSIS se Nan ee ee ee eee 7, 404 Group 2: Those whose chest X-ray film was coded 2, meaning changes con- sistent with simple silicosis a ea ee ee ee ee 267 Group 3: Those whose chest X-ray film was coded 3, meaning changes con- sistent with complicated Silicosis sees es a es here 2 ei ee eee 146 These three groups are referred to in this report as the groups with no silicosis, simple silicosis, and complicated silicosis. Only 1.7 percent of the films in group 1 were coded 1; the rest were coded 0. Table A.1 shows the average values for each of the four measures of pulmonary ventilatory function tests for men with no silicosis, simple silicosis, and complicated silicosis. For every one of the four measurements of pulmonary function, the average value is less for those with silicosis than for those with no silicosis. Also, for every one of the four measurements, the average value is less for those with complicated silicosis than for those with simple silicosis. TABLE A.1.—Average values for four measurements of pulmonary function of metal mine workers 35 years of age and over with and without silicosis a ee eee ee Measurement of pulmonary function Metal mine workers with— Number of ner Se workers PEF FEV; FVC FEV,/FVC NOSSILCOSIS wae eye et a ey 7, 404 483 2A9 4,22 70. 1 Simplersilicosicneaes 4 on oe eee. 267 44] 2. 61 3. 95 66. 3 Complicated silicosis___________ 146 382 2. 41 3. 68 63. 1 The comparisons in table A.1 are complicated by the fact that the metal mine workers with silicosis tend to be older and to have worked more years in mining than those with no silicosis and, as noted above, these factors no doubt have some effect on pulmonary function. The decline observed in table A.1 cannot, therefore, be entirely attributed to silicosis. Table A.2 shows that the average metal mine worker with complicated silicosis was 8 years older and worked in under- ground mining 10 years longer than the average metal mine worker with no silicosis. He has also spent more total years in mining and](https://iiif.wellcomecollection.org/image/b32183136_0252.jp2/full/800%2C/0/default.jpg)
