Sussex County Average 1999 NATA Modeled Air Concentrations Compared to Health Benchmarks
Pollutant
Modeled
Air Concentration (ug/m3)
Health
Benchmark (ug/m3)
Risk
Ratio
%
Contribution from
Major Sources
Area
Sources
On-road
Mobile Sources
Nonroad
Mobile Sources
Background
Acetaldehyde
0.9
0.45
2
0.2%
3%
34%
6%
57%
Acrolein
0.05
0.020
2
0.003%
33%
55%
12%
0%
Arsenic Compounds
0.00003
0.00023
0.1
51%
49%
0%
0%
0%
Benzene
0.7
0.13
5
0.05%
11%
28%
10%
52%
Bis(2-ethylhexyl)phthalate
2
0.42
4
0.001%
0%
0%
0%
100%
1,3-Butadiene
0.04
0.033
1.3
0%
5%
30%
13%
52%
Cadmium Compounds
0.00001
0.00024
0.04
13%
87%
0%
0.4%
0%
Carbon Tetrachloride
0.3
0.067
4
0%
0.06%
0%
0%
100%
Chloroform
0.05
0.043
1.3
8%
22%
0%
0%
71%
Chromium (hexavalent form)
0.00001
0.000083
0.2
4%
69%
26%
1%
0%
1,4-Dichlorobenzene
0.02
0.091
0.2
0.05%
100%
0%
0%
0%
1,3-Dichloropropene
0.03
0.25
0.1
0%
100%
0%
0%
0%
Diesel Particulate Matter
1
0.0033
413
0%
0%
46%
54%
*
Ethylene Dibromide
0.02
0.0017
9
0.0003%
0.005%
0%
0%
100%
Ethylene Dichloride
0.03
0.038
0.8
0.07%
0.1%
0%
0%
100%
Ethylene Oxide
0.0008
0.011
0.1
0.07%
100%
0%
0%
0%
Formaldehyde
1
0.077
13
0.08%
5%
21%
6%
67%
Methyl Chloride
1
0.56
2
0.002%
0.2%
0%
0%
100%
Naphthalene
0.02
0.029
0.6
0.04%
70%
27%
3%
0%
Nickel Compounds
0.0002
0.0064
0.03
15%
77%
7%
0.5%
0%
Perchloroethylene
0.09
0.17
0.5
0.2%
22%
0%
0%
78%
1,1,2,2-Tetrachloroethane
0.04
0.017
3
0.1%
0.3%
0%
0%
100%
Chemicals with risk ratios greater than or equal to 1 are
in bold.
Risk Ratios in italics are based on noncarcinogenic effects.
The symbol ug/m3 is micrograms per cubic meter,
the amount (in micrograms) of a chemical in a cubic
meter of air. This is also known as a concentration.
* For diesel particulate matter, onroad and nonroad
concentrations include a model-estimated background
concentration.
