Table 2. Exposure of cases and controls according to task-based (Asbestos and PAH) and job-specific (crystalline silica) scores.
|
Asbestos
|
PAH
|
Crystalline silica
|
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Controls (%) | Cases (%) | OR | Controls (%) | Cases (%) | OR | Controls (%) | Cases (%) | OR | |
| Maximum level a | |||||||||
| Non-exposed | 255 (48.0) | 71 (28.9) | 1.0 | 408 (76.8) | 154 (62.6) | 1.0 | 194 (36.5) | 53 (21.5) | 1.0 |
| Unknown but self-reported | 18 (3.4) | 13 (5.3) | 2.6* | ||||||
| L1 | 105 (19.8) | 40 (16.3) | 1.4 | 83 (15.6) | 57 (23.2) | 1.8** | 98 (18.3) | 32 (13.0) | 1.2 |
| L2 | 119 (22.4) | 77 (31.3) | 2.3*** | 5 (1) | 1 (0.4) | 0.5 | 130 (24.5) | 73 (29.7) | 2.1*** |
| L3 | 34 (6.4) | 45 (18.3) | 4.8*** | 35 (6.6) | 34 (13.8) | 2.6*** | 109 (20.5) | 88 (35.8) | 3.0*** |
| Cumulative exposure by approximate quartiles | |||||||||
| Non-exposed | 255 (48.0) | 71 (28.9) | 1.0 | 408 (76.8) | 154 (62.6) | 1.0 | 194 (36.5) | 53 (21.5) | 1.0 |
| Q1 | 80 (15.1) | 34 (13.8) | 1.5 | 45 (8.5) | 19 (7.7) | 1.1 | 97 (18.3) | 32 (13.0) | 1.2 |
| Q2 | 72 (13.6) | 40 (16.3) | 2.0* | 35 (6.6) | 29 (11.8) | 2.2** | 85 (16.0) | 46 (18.7) | 2.0** |
| Q3 | 72 (13.6) | 46 (18.7) | 2.3*** | 24 (4.5) | 21 (8.5) | 2.3** | 81 (15.3) | 53 (21.5) | 2.4*** |
| Q4 | 52 (9.8) | 55 (22.4) | 3.8*** | 19 (3.6) | 23 (9.4) | 3.2*** | 74 (13.9) | 62 (25.2) | 3.1*** |
Abbreviations: OR=odds ratios; PAH=polycyclic aromatic hydrocarbons.
*P<0.05, **P<0.01 ***P<0.001.
a
Asbestos: L1= <1 fiber per ml, L2= 1–10 fibers per ml, L3=>10fiber per ml; PAH: <200 ng m−3, 200–1000 ng m−3, >1000 ng m−3; Crystalline silica=1, 10, 100 arbitrary units.