Table 2

Associations between wastewater impacted public drinking water and breast cancer.


Cases
Controls
Adjusted OR (95% CI)a
Adjusted OR (95% CI)b

Average annual excess nitrate-N concentration (mg/L)
0 to < .3
327
287
1.0 (reference)
1.0 (reference)
.3 to < .6
201
175
1.0 (0.7 – 1.3)
0.9 (0.7 – 1.3)
.6 to < .9
155
152
0.9 (0.6 – 1.2)
0.8 (0.6 – 1.1)
.9 to < 1.2
120
112
0.9 (0.6 – 1.2)
0.9 (0.6 – 1.2)
≥ 1.2
21
19
0.9 (0.5 – 1.7)
1.0 (0.5 – 1.9)
Sum of annual excess nitrate-N concentrations (mg/L)
0 to < .01
19
18
0.8 (0.4 – 1.6)
0.9 (0.5 – 1.9)
.01 to < .1
45
42
0.9 (0.6 – 1.5)
1.1 (0.7 – 1.7)
.1 to < 1
119
118
0.9 (0.7 – 1.2)
1.1 (0.8 – 1.5)
1 to < 10
474
418
1.0 (reference)
1.0 (reference)
≥ 10
167
149
1.0 (0.8 – 1.3)
0.9 (0.7 – 1.2)
Number of years exposed to excess nitrate-N > 1 mg/L
0
562
504
1.0 (reference)
1.0 (reference)
< 2
58
52
1.0 (0.7 – 1.5)
1.1 (0.7 – 1.6)
2 to < 4
93
77
1.0 (0.7 – 1.4)
1.0 (0.7 – 1.4)
4 to < 6
36
44
0.8 (0.5 – 1.2)
0.7 (0.5 – 1.2)
6 to < 8
50
43
1.0 (0.6 – 1.5)
0.9 (0.6 – 1.4)
≥ 8
25
25
0.9 (0.5 – 1.7)
0.9 (0.5 – 1.5)
OR odds ratio.
CI confidence interval.




a Adjusted for diagnosis/reference year, age at diagnosis/reference year, birth decade, study, vital status, previous breast cancer diagnosis, age at first birth, family history of breast cancer, and education.

b Adjusted for variables in analysis (a), years on Cape Cod and years on the Cape squared.

Brody et al. Environmental Health: A Global Access Science Source 2006 5:28   doi:10.1186/1476-069X-5-28