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Information provided for informational purposes onlyNote: EPA no longer updates this information, but it may be useful as a reference or resource.
Statewide Exposure Concentration Estimates:
Displays a horizontal bar for each State that represents the central part of the distribution of the exposure concentrations in that State (the 25th to 75th percentile) as well as the median value for the selected pollutant. If the air pollutant is a carcinogen, the bar chart also diplays a line at the exposure concentrations representing the "1 in a Million Cancer Risk", the "10 in a Million Cancer Risk" and the "100 in a Million Cancer Risk". For pollutants with non-cancer risks, the bar chart displays a line at the exposure concentrations representing a " Hazard Quotient = 1.0" (for reference purposes, some charts contain a line representing a Hazard Quotient = 0.1)

Percent Contribution:
Contains horizontal bars representing the percent contribution of four source types (major, area and other, onroad mobile, and nonroad mobile) as well as the contribution of the estimated background to the statewide average exposure concentration estimate for the selected pollutant.

Individual State Exposure Concentration Estimates:
Depicts the median exposure concentrations for each pollutant in the NATA analysis on a single chart. A chart is provided for each state. Pollutant exposure concentration symbols are plotted to give the relationship of the state's median exposure concentrations to the cancer or non-cancer risk level.

Select a chart type (Statewide Estimates; Percent Contribution or Individual State Exposure Concentration Estimates) and a pollutant (where necessary) below.

View a Chart in Adobe Acrobat PDF format
Statewide Estimates
Percent Contribution
Individual State Exposure Concentration Estimates

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