Table 4.
RRs (95% CIs) for bladder cancer in relation to nitrate exposure from drinking water, with respect to cigarette smoking (never/ever): the Netherlands Cohort Study, 1986–1995.
| Nitrate intake from drinking water
|
|||||
|---|---|---|---|---|---|
| Low (≤ 3.4 mg/day)
|
High (> 3.4 mg/day)
|
||||
| Cases | Subcohort (PY) | Cases | Subcohort (PY) | RR (95% CI) | |
| Cigarette smoking | |||||
| Never | 58 | 7,692 | 45 | 6,764 | 0.99 (0.64–1.53)a |
| Ever | 352 | 13,392 | 416 | 14,480 | 1.13 (0.94–1.35)b |
PY, person-years.
a
Adjusted for age (years), sex, and nitrate exposure from drinking water.
b
Adjusted for age (years), sex, smoking amount (cigarettes/day), smoking duration (years), and nitrate exposure from food.