Table 3.
Frequency of different dimensions of exposure to cotton dust and wool dust in two studies in Montreal, Canada, cases and controls combined
| Exposure characteristic | Cotton Dust | Wool Dust | ||
|---|---|---|---|---|
| Study 1 | Study 2 | Study 1 | Study 2 | |
| (N=2739) | (N=2716) | (N=2739) | (N=2716) | |
| % | % | % | % | |
| Level of exposure | ||||
| Non-substantial | 4.1 | 17.2 | 2.5 | 7.4 |
| Substantial | 4.0 | 1.6 | 3.4 | 1.0 |
| Exposure concentrationa | ||||
| Low | 2.6 | 15.9 | 1.6 | 6.9 |
| Medium | 4.2 | 2.4 | 3.8 | 1.4 |
| High | 1.3 | 0.5 | 0.5 | 0.2 |
| Confidence levela | ||||
| Possible | 0.1 | 2.0 | 0.04 | 1.1 |
| Probable | 1.3 | 5.1 | 1.1 | 1.9 |
| Definite | 6.7 | 11.7 | 4.8 | 5.5 |
| Frequency a | ||||
| <5% of work week | 0.3 | 0.4 | 0.3 | 0.2 |
| 5-30% of work week | 1.6 | 3.8 | 1.4 | 1.7 |
| >30% of work week | 6.2 | 14.4 | 4.3 | 6.5 |
| Duration | ||||
| 1-5 years | 2.2 | 7.7 | 1.3 | 3.5 |
| 6-20 years | 3.1 | 6.9 | 2.2 | 3.3 |
| >20 years | 2.8 | 4.2 | 2.4 | 1.6 |
a Value is an average weighted by job duration, if reported for >1 job and/or time period.