Table 2 Odds ratios and 95% confidence intervals for chronic lymphoid leukaemias and specific benzene exposure metrics for the Australian study ever employed at a refinery and ever not employed at a refinery
Ever employed at refinery | Not ever employed at a refinery | |||
---|---|---|---|---|
Cases/controls | Odds ratios (95% CI) | Cases/controls | Odds ratios (95% CI) | |
Cumulative benzene exposure beyond zero (p.p.m.-years) | ||||
⩽0.348–2.93 | 3/15 | 1 | 7/20 | 1 |
>2.93 | 9/11 | 3.75 (0.76, 18.55) | 4/13 | 0.71 (0.16, 3.27) |
Maximum benzene exposure intensity (p.p.m.) beyond 0.016 p.p.m. | ||||
⩽0.016–0.118 | 2/13 | 1 | 4/17 | 1 |
>0.118–0.413 | 7/8 | 5.65 (0.87, 36.83) | 3/8 | 1.74 (0.27, 11.19) |
>0.413 | 3/5 | 2.33 (0.34, 15.91) | 4/8 | 1.83 (0.32, 10.53) |
Average benzene exposure intensity (p.p.m.) beyond 0.016 p.p.m. | ||||
⩽0.016–0.081 | 2/10 | 1 | 5/17 | 1 |
>0.081–0.259 | 7/11 | 2.98 (0.53, 16.71) | 2/10 | 0.66 (0.10, 4.61) |
>0.259 | 3/5 | 2.07 (0.27, 15.87) | 4/6 | 1.67 (0.32, 8.70) |
Duration of employment beyond zero (years) | ||||
⩽15.6–28 | 6/13 | 1 | 9/28 | 1 |
>28 | 6/13 | 1.14 (0.10, 12.66) | 2/5 | 0.63 (0.05, 7.49) |