Cancer incidence among wastewater workers relative to that of water supply workers 1965–97 (inclusive); number of cases (n) and relative risk estimates (RR) with 95% CI, by cancer site
| Diagnosis (ICD-7) | n | RR | (95% CI) |
|---|---|---|---|
| All malignant neoplasms (140–205) | 68 | 1.27 | (0.97 to 1.67) |
| Respiratory cancer (160–9) | 20 | 1.65 | (1.00 to 2.74) |
| Lung cancer (162.0–1) | 17 | 1.48 | (0.46 to 4.74) |
| Digestive cancer (150–9) | 14 | 1.38 | (0.71 to 2.71) |
| Primary liver cancer (155) | 4 | 8.9 | (1.5 to 51.5) |