Association between Six Environmental Chemicals and Lung Cancer Incidence in the United States
Table 4
Association of lung cancer incidence with six selected chemicals using linear regression by region*.
Metro counties
Nonmetro counties
Carcinogens
Coefficient
value <
Coefficient
value <
Arsenic (yes : no)
−4.10
0.60
—
—
Arsenic (in continuous)
−0.70
0.58
—
—
1,3-butadiene (yes : no)
2.33
0.62
6.16
0.35
1,3-butadiene (in continuous)
0.40
0.53
0.86
0.20
Cadmium (yes : no)
4.04
0.38
0.19
0.98
Cadmium (in continuous)
0.20
0.84
0.24
0.89
Chromium (yes : no)
3.65
0.25
6.60
0.04
Chromium (in continuous)
0.42
0.34
1.65
0.004
Formaldehyde (yes : no)
4.30
0.22
12.15
0.005
Formaldehyde (in continuous)
0.59
0.12
1.35
0.01
Nickel (yes : no)
3.48
0.27
7.49
0.02
Nickel (in continuous)
0.39
0.37
1.56
0.008
No release of selected chemicals (reference)
Low total amount of release†
2.09
0.63
4.82
0.08
High total amount of release†
6.64
0.08
17.53
0.0002
Total amount (in continuous)
0.61
0.10
1.37
0.0001
*The amount of each selected chemical in continuous and total amount of all selected chemicals were log transformed. †The cut point for low or high release of total amount of selected chemicals was set at 2000 pounds annually (low: <2000 pounds, high: ≥2000 pounds). Covariates included proportion of nonwhite population in 1990, prevalence of smoking in 2000, proportion of male population, proportion of people with college or higher education in 1990, and proportion of families below poverty in 1990.
