Table 2 Mortality from pharyngeal cancer by cumulative exposure to formaldehyde (own calculations, based on data from table 5 [5])
Cumulative exposure (ppm-years) | OBS | EXP | SMR (95% CI) |
|---|---|---|---|
0 (never) | 2 | 1.1 | 1.82 (0.22 – 6.57) |
(0.0, 0.5] | 8 | 3.6 | 2.22 (0.96 – 4.38) |
(0.5, 5.5] | 3 | 4.1 | 0.73 (0.15 – 2.14) |
(5.5, ∞) | 2 | 2.6 | 0.77 (0.09 – 2.78) |
>0 (ever) | 13 | 10.3 | 1.26 (0.67 – 2.16) |