Table 4 Land-use regression model results for benzene, BTEX, and formaldehyde. Final model terms listed in order of importance based on partial R ²

Benzene (n = 69)

0.65

Intercept

0.052

0.188

0.783

--

Number of signals within 400 meters

0.017

0.002

<.0001

0.36

Length of interstate, state, and county highways within 100 meters (km)

0.591

0.101

<.0001

0.18

Reference site mean

0.799

0.340

0.022

0.03

BTEX (n = 67)

0.70

Intercept

0.568

0.801

0.481

--

Number of signals within 450 meters

0.074

0.009

<.0001

0.34

Kernel-weighted smooth of solvent-based industry locations (500 meter radius)

0.072

0.013

<.0001

0.14

Reference site mean

0.873

0.328

0.010

0.03

Formaldehyde (n = 69)

0.83

Intercept

−0.725

0.224

0.002

--

Reference site mean

1.209

0.119

<.0001

0.28

Number of signals within 400 meters

0.020

0.004

<.0001

0.07

Road length within 100 meters (km)

0.561

0.112

<.0001

0.07

Built space within 100 meters (km²)

2.477

0.716

0.001

0.03