Age adjusted incidence rates per 100 000 person-years for respiratory and cardiovascular diseases
| Disease/workers | Incidence /100000 | Rate ratio | 95% CI | |
|---|---|---|---|---|
| High dust† | Low dust† | |||
| *Owing to small number of cases, the test was based on crude rates. | ||||
| †Classification into high and low dust categories: | ||||
| – Granite workers: high, ⩾20 mg/m3; low, <20 mg/m3 | ||||
| – Cotton mill workers: high, >10 mg/m3; low, ⩽10 mg/m3 | ||||
| – Foundry workers: high comprised floor and machine moulders and fettlers and the labourers assisting them; low comprised core makers, furnace men, casters, truck drivers, others | ||||
| – Metal workers: high comprised iron foundry workers; low comprised metal product and electrical workers. | ||||
| All respiratory diseases | ||||
| Granite workers | 1385.1 | 942.0 | 1.5 | 1.19 to 1.92 |
| Cotton mill workers | 550.1 | 130.3 | 4.0 | 1.10 to 14.49* |
| Foundry workers | 1181.7 | 1020.9 | 1.2 | 0.92 to 1.47 |
| Metal workers (three industries) | 885.3 | 577.6 | 1.5 | 1.26 to 1.81 |
| All cardiovascular diseases | ||||
| Granite workers | 2005.3 | 1877.2 | 1.1 | 0.89 to 1.29 |
| Cotton mill workers | 1029.6 | 863.8 | 1.2 | 0.68 to 2.25* |
| Foundry workers | 1832.2 | 1928.6 | 1.0 | 0.79 to 1.14 |
| Metal workers (three industries) | 1425.2 | 1199.5 | 1.2 | 1.04 to 1.35 |
| Ischaemic heart disease | ||||
| Granite workers | 943.2 | 769.7 | 1.2 | 0.94 to 1.58 |
| Cotton mill workers | 253.7 | 146.4 | 1.9 | 0.47 to 7.45* |
| Foundry workers | 882.8 | 973.1 | 0.9 | 0.71 to 1.16 |
| Metal workers (three industries) | 625.1 | 435.8 | 1.4 | 1.19 to 1.74 |