SUSSEX County Average 2005 NATA Modeled Air Concentrations Compared to Health Benchmarks
Pollutant
Modeled
Air Concentration (ug/m3)
Health
Benchmark (ug/m3)
Risk
Ratio
%
Contribution from
Point Sources
Nonpoint
Sources
On-road
Mobile Sources
Nonroad
Mobile Sources
Background & Secondary
Acetaldehyde
1.4
0.45
3.1
0%
2%
1%
1%
96%*
Acrolein
0.022
0.020
1.1
<1%
11%
5%
7%
77%*
Arsenic Compounds
0.0004
0.00023
1.7
5%
5%
1%
1%
88%
Benzene
0.69
0.13
5.3
<1%
9%
8%
5%
78%
1,3-Butadiene
0.047
0.033
1.4
<1%
<1%
9%
6%
85%
Cadmium Compounds
0.00007
0.00024
0.3
2%
24%
0%
<1%
74%
Carbon Tetrachloride
0.61
0.067
9.1
0%
<1%
0%
0%
100%
Chloroform
0.071
0.043
1.6
<1%
17%
0%
0%
83%
Chromium (hexavalent form)
0.0001
0.000083
1.3
3%
4%
1%
<1%
92%
Cobalt Compounds
0.000012
0.00011
0.1
95%
5%
0%
0%
0%
1,4-Dichlorobenzene
0.06
0.091
0.7
<1%
24%
0%
0%
76%
1,3-Dichloropropene
0.028
0.25
0.1
0%
100%
0%
0%
0%
Diesel Particulate Matter
0.13
0.0033
40
0%
0%
54%
46%
0%
Ethylbenzene
0.045
0.4
0.1
<1%
14%
43%
43%
0%
Ethylene Oxide
0.0075
0.011
0.7
<1%
3%
0%
0%
97%
Formaldehyde
1.4
0.077
19
0%
2%
2%
1%
95%*
Methyl Chloride
1.2
0.56
2.1
0%
<1%
0%
0%
100%
Naphthalene
0.043
0.029
1.5
<1%
29%
10%
3%
58%
Nickel Compounds
0.0002
0.0021
0.1
26%
21%
2%
<1%
51%
PAH/POM
0.005
0.0072**
0.7
<1%
91%
3%
6%
0%
Perchloroethylene
0.084
0.17
0.5
<1%
22%
0%
0%
78%
1,1,2-Trichloroethane
3.7E-7
0.063
5.9E-6
59%
41%
0%
0%
0%
Chemicals with risk ratios greater than or equal to 1 are
in bold.
Risk Ratios based on noncarcinogenic effects are in italics.
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. *Acetaldehyde, acrolein and formaldehyde concentration estimates include secondary formation, which is the process by which chemicals in the air are transformed into other chemicals.
**PAH/POM is "polycyclic aromatic hydrocarbons/polycyclic organic matter." These define a broad class of compounds. The chemicals making up this class were broken up into 8 groups based on toxicity, and each group was assigned a cancer-weighted toxicity estimate. 0.0072 ug/m3 is the health benchmark average across the 8 groups.
