2014 RISK RESULTS FOR NEW JERSEY
To determine whether the air toxics
included in USEPA’s National-Scale Air
Toxics Assessment (NATA) could be a potential human
health problem in New Jersey, NJDEP compares the estimated NATA
air concentrations to their chemical-specific health
benchmarks. We divided the modeled air
concentration by the health benchmark
to get a number we call a risk ratio. If the risk ratio
for a specific chemical is greater than one, it may be of concern. The risk ratio also shows
just how much higher or lower the estimated air concentration
is than the health benchmark. For more information,
see How We Estimate Risk
from Air Toxics. For "Air Toxics of Concern" (see below), results of NJDEP's risk assessment are presented in two ways: State Risk Maps, and County Risk Ratio Tables.
New Jersey’s methods for estimating risk using
the NATA results are somewhat different from USEPA’s
methods, and therefore risk results presented here
are different from the risk estimates found on the
USEPA's NATA web site. New Jersey compares health benchmarks to the modeled ambient concentrations, while USEPA converts the ambient data into "exposure concentrations" using an exposure model that incorporates numerous assumptions about the demographics and activity patterns within a census tract. Resulting exposure concentrations may either be higher or lower than ambient concentrations. Dispersion models have been tested over time by comparisons with ambient monitoring data, and have generally been shown to be comparable within a factor of two. However, for exposure modeling we feel that at this stage of development it adds a level of complexity and uncertainty that confuses rather than clarifies the true levels of exposure.
AIR TOXICS OF GREATEST CONCERN IN NEW JERSEY FOR 2014
Of the 181 air toxics that USEPA included in the 2014 NATA, about one-third do not have toxicity values, or corresponding health benchmarks. For those that do, our analysis of the state and county average air toxics concentrations indicates that 14
of the pollutants are "of concern" because they were predicted to exceed their
health benchmarks in one or more counties.
concentrations of these pollutants vary around the
state, depending on the type of sources that emit
them. This is summarized in the table below. For
more information on source types click on point,
area, and mobile sources, and background
concentrations. For more information on which areas are impacted by these chemicals of concern, see the chemical-specific maps below.
2014 CHEMICALS OF CONCERN
IN NEW JERSEY
Above Health Benchmarks
* For more information on which areas are impacted
by the chemicals of concern, see the chemical-specific
SHOWING THE DISTRIBUTION OF THE 2014 AIR TOXICS
OF CONCERN IN NEW JERSEY
see a state map showing the spatial variation in
modeled air concentrations (at the census-tract level) for one of the fourteen
chemicals of concern, click on the chemical name:
For information about using Health Benchmarks, click here
COUNTY RISK RATIO TABLES
see a statewide or county -specific table containing
the 2014 NATA-based risk results (including ambient air concentrations, health
benchmarks, risk ratios, and source category contributions)
for each of the 14 air toxics of concern, click on
statewide or the county names below.
For Each Table:
Chemicals with risk ratios greater than or equal
to 1 are in bold.
Risk Ratios in italics are based on noncarcinogenic
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.
Acetaldehyde 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.
Previous NATA Risk Results
USEPA has completed six National-Scale Air Toxics Assessments, every third year beginning with 1996. Before that, they conducted a "Cumulative Exposure Project" (CEP) for 1990 which also included an assessment of air toxics. However, they emphasize that the methods used to conduct emissions inventories, modeling, and risk assessment vary somewhat from year to year, so the results are not exactly comparable.
New Jersey's interpretation of past USEPA data is available below.
2011 NATA Risk Results for NJ
2005 NATA Risk Results for NJ
2002 NATA Risk Results for NJ
1999 NATA Risk Results for NJ
1996 NATA Risk Results for NJ
1990 CEP Results for NJ