Case control study of the geographic variability of exposure to disinfectant byproducts and risk for rectal cancer

Table 5 Quartiles of odds ratios¹ of risk for rectal cancer for total daily ingestion (ug/day) from tap water of bromoform from tap water in Monroe County, New York State

Bromoform Quartile (ug/day)	OR (95%CI)	β	pvalue
1 (Low) (0.90–0.64)	-----	-----	-----
2 (0.65–0.97)	1.42 (0.73–2.74)	0.35	0.42
3 (0.98–1.68)	1.63 (0.85–2.69)	0.49	0.10
4 (High)(1.69–15.43)	2.32 (1.22–4.39)	0.84	0.01

1: abbreviations are as follows: OR, odds ratio; CI, confidence interval
2: exposure determined from consumption of tap water and estimated levels of bromoform (ug/l)
3: Results adjusted for covariates listed in Table 3
4: p-value for linear trend: 0.002

ISSN: 1476-072X