Lung cancer mortality by ILO radiographic category and cumulative exposure to crystalline silica
| Cumulative exposure (mg/m3-year) | Radiographic category | ||||||
|---|---|---|---|---|---|---|---|
| <1/0 (n = 1798)1-150 | ⩾1/0 or large opacity (n = 81) | ||||||
| Deaths | SMR | (95% CI) | Deaths | SMR | (95% CI) | ||
| <0.5 | 13 | 1.05 | (0.56 to 1.79) | 0 | 0 | (0 to 12.2) | |
| 0.5–1.9 | 13 | 0.86 | (0.46 to 1.48) | 0 | 0 | (0 to 19.3) | |
| 2.0–4.9 | 10 | 1.25 | (0.60 to 2.29) | 0 | 0 | (0 to 5.32) | |
| ⩾5.0 | 12 | 2.40 | (1.24 to 4.20) | 4 | 2.94 | (0.80 to 7.53) | |
| Total | 48 | 1.19 | (0.87 to 1.57) | 4 | 1.57 | (0.43 to 4.03) | |
↵1-150 Includes 1728 with <1/0 throughout, and 70 who later converted to ⩾1/0
SMR = standardised mortality ratio based on rates for US white men, 1942–94.
95% CI = 95% confidence interval for SMR