Air Toxics of Concern
	State Maps
	County Risk Ratio Tables

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 2002

Of the 181 air toxics that USEPA included in the 2002 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 21 of the pollutants are "of concern" because they were predicted to exceed their health benchmarks in one or more counties. 20 of these are cancer-causing (carcinogenic) chemicals, and one (acrolein) is evaluated as a non carcinogen. Predicted 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.

2002 CHEMICALS OF CONCERN IN NEW JERSEY

Pollutant Number/Name of Counties Above Health Benchmarks Primary Emissions Source Acetaldehyde 21 Mobile, background Acrolein 21 Mobile Arsenic Compounds 19 Background, area Benzene 21 Mobile, Background 1,3-Butadiene 21 Mobile, background Cadmium Compounds 1 (Warren) Major Carbon Tetrachloride 21 Background Chloroform 21 Area, background Chromium VI 19 Major, Background 1,4-Dichlorobenzene 8 Area, Background 1,3-Dichloropropene 1 (Hudson) Area Diesel Particulate Matter 21 Mobile Ethylbenzene 7 Mobile Ethylene Oxide 7 Area, Background Formaldehyde 21 Mobile, background Methyl Chloride 21 Background Methyl tert-Butyl Ether 21 Background Naphthalene 19 Area PAH/POM 18 Area Perchloroethylene 7 Area, background 1,1,2-Trichloroethane 1 (Salem) Area

* For more information on which areas are impacted by the chemicals of concern, see the chemical-specific maps below.

MAPS SHOWING THE DISTRIBUTION OF THE 2002 AIR TOXICS OF CONCERN IN NEW JERSEY

To see a state map showing the spatial variation in modeled air concentrations (at the census-tract level) for one of the twenty-one chemicals of concern, click on the chemical name:

For information about using Health Benchmarks, click here

COUNTY RISK RATIO TABLES

To see a statewide or county -specific table containing the 2002 NATA-based risk results (including ambient air concentrations, health benchmarks, risk ratios, and source category contributions) for each of the 21 air toxics of concern, click on the state name or county names below.

For Each Table: