|
Variable
|
All systems (n = 39,466)
|
Low nitrate CWSsa (n = 37,819)
|
High nitrate CWSsb (n = 1647)
|
|---|
|
Percent Black, non-Hispanic (%)
|
8.4
|
8.6
|
4.0#
|
|
Percent Hispanic (%)
|
11.4
|
11.1
|
18.1#
|
|
Percent poverty (%)
|
15.7
|
15.7
|
14.8#
|
|
Percent home ownership (%)
|
70.1
|
70.2
|
68.6#
|
|
Percent urban households (%)
|
36.5
|
36.3
|
40.3#
|
|
Percent cropland (%)
|
20.2
|
19.6
|
35.5#
|
|
Livestock (number per 100 acres)
|
9.5
|
9.2
|
16.6#
|
- Note: Means calculated by imputing zero for nondetects
- aMean nitrate < 5 mg/L NO3-N
- bMean nitrate ≥ 5 mg/L NO3-N
- #Mean significantly different between two groups (high vs. low nitrate) using unequal variances t-test, (p < 0.001)
