Air Toxics

Air toxics are those air pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive and birth defects. The degree to which a toxic air pollutant affects a person’s health depends on many factors including the quantity and toxicity of the pollutant to which the person is exposed as well as the duration and frequency of exposure.

Air toxics can come from natural sources (e.g., radon gas coming from the ground) or man-made sources such as motor vehicles and industrial processes. Air toxics that deposit onto soil or into lakes and streams can affect ecological systems and eventually human health through consumption of contaminated food.

The federal Clean Air Act targets 188 toxic air pollutants for emissions reduction. These 188 air toxics are known as hazardous air pollutants. Examples include benzene, which is found in gasoline; perchloroethylene, which is emitted from some dry cleaning facilities; and methylene chloride, which is used as a solvent and paint stripper by a number of industries. Other examples are dioxin, asbestos and metals such as mercury, chromium and lead. The Kentucky Department for Environmental Protection ensures that industries in the state comply with the limits on toxic air pollutant emissions established under the Clean Air Act.

Air Toxics and Air Pollution

Over the years, the Division for Air Quality (DAQ) has instituted many programs and measures to address criteria pollutants such as NOx, SO2, CO and PM. Much improvement in air quality has been realized by our efforts. The result has been a level of improved ambient air quality that was perhaps just a dream 30 years ago. Although our job to control criteria pollutants continues, we are now at the point that we must turn our attention to solving the complex issues associated with toxic air pollutants and the negative impacts that toxic emissions can have on human health and the environment.

EPA has encountered significant delays in the issuance of its technology-based MACT standards and has made limited progress in the development of regulations to protect the public health from the residual risk posed by hazardous air pollutants after compliance with technology-based Maximum Achievable Control Technology (MACT) standards. Therefore, the department believes it is necessary to develop a state regulatory program that establishes clear-cut implementation procedures to identify and control toxic air pollutants to levels that are consistent with protection of health-related values.

In order to accomplish this objective, the Environmental and Public Protection Cabinet (EPPC) established a workgroup in late 2004, comprised of individuals who have scientific knowledge and expertise in the fields of toxicology, air quality environmental protection and risk assessment. This workgroup made presentations and submitted comments to assist in the formulation of a regulatory program to assess and control toxic emissions in the commonwealth from stationary sources. This group met on several occasions and discussed the various aspects of air toxics and risk assessment with EPPC, EPA and the public. Upon conclusion of the meetings, DAQ embarked on an effort to review all input and began developing a regulatory package.

DAQ Director John Lyons sent a letter to workgroup participants requesting an evaluation of potential implementation procedures using a scenario that would reflect the general parameters of the federal approach to the regulation of residual risk from air toxics as presented in workgroup meetings. The comments that were submitted by work group members in response to the department's request can be viewed here. (Note: Member responses are scanned PDF documents. They have been compressed using WinZip. You can visit WinZip.com for a free download if you do not have this program on your computer.)

For an overview of the progress that the Department for Environmental Protection, Division for Air Quality is making concerning toxic emissions go to: 2004 Air Toxics Sampling in Kentucky.

Air Toxics Workgroup Presentation_September 2005

Notes on: U.S. EPA Region 4 Air Toxics Relative
Risk Screening Analysis (Sept. 27, 2002)

Background
Region 4 of the United States Environmental Protection Agency (U.S. EPA) published a screening analysis for the states in Region 4 on Sept. 27, 2002. The analysis is to be used as a tool for focusing risk reduction strategies in those areas with a higher potential for air toxics impacts. The analysis was intended to identify those areas with higher potential for health risk in combination with a higher number of people with the potential to be impacted. This screening-level analysis used several measures of potential health impacts, total population density, and population density of sensitive subpopulations in a scoring system to rank the counties in Region 4.

The spreadsheet produced by U.S. EPA consists of the 736 counties for the eight states in U.S. EPA Region 4. The columns of the spreadsheet represent the criteria that were used in the relative risk screening conducted by Region 4 staff. These criteria and their contribution to the ranking score are: 1996 National Air Toxics Assessment (NATA) average individual cancer risk for the county (10 percent), 1996 NATA average individual noncancer hazard (10 percent), 1996 NATA average diesel PM concentration (5 percent), 1999 Risk Screening Environmental Indicator relative hazard ranking based on 1999 TRI data (25 percent), total age-adjusted respiratory disease mortality (5 percent), total age-adjusted cardiac disease mortality (5 percent), total cancer incidence from state cancer registry (5 percent), total population density (15 percent), population density of people under age 18 (10 percent), and population density of people over age 65 (10 percent). Half the score is based on risk calculations, 15 percent of the score is based on disease incidence (influenced primarily by lifestyle choices and genetics, and some environmental issues), and 35 percent of the score was based on population characteristics. The NATA data is based on 32 Hazardous Air Pollutants and diesel PM.

Observations:
The Kentucky Department for Environmental Protection evaluated this screening analysis and the ranking within each of the individual categories.

Overall Rank: Jefferson County, Kentucky ranked highest of the 736 counties in Region 4. Five other Kentucky counties were in the top 50 (Muhlenberg (10th), Kenton (17th), Campbell (23rd), Fayette (27th), Boyd (35th) and Boone (48th))
When sorted by NATA cancer risk, Boyd County is 6th and Jefferson County is 8th out of 736 counties, with Kenton, Campbell, and Greenup also in the top 20.
When sorted by NATA noncancer hazard, Jefferson County is 10th among counties in U.S. EPA Region 4, with Bath, Kenton and Campbell also in the top 20.
When sorted by diesel PM, Lyon County is 5th, Jefferson County is 7th, Campbell is 8th and Kenton is 10th among all counties.
When sorted by the 1999 TRI screening results, Muhlenberg County was 1st, Jefferson County was 4th and Carroll County was 11th.
When sorted by total cancer incidence, 14 Kentucky counties were in the top 25. The top 10 include: Menifee (3rd), Whitley (5th), Wolfe (8th) and Marion (10th).
When sorted by respiratory disease mortality, 27 of top 50 counties are in Kentucky and 52 of top 100 counties are in Kentucky.
When sorted by cardiac disease mortality, the highest county in Kentucky (Martin) is 31st and seven are in the top 50.
When sorted by total population, Jefferson County is 11th, Fayette is 37th.
When sorted by total population density, Jefferson County is 4th, Kenton is 17th, Fayette is 18th.
When sorted by population density over age 65, Jefferson County is 2nd and Kenton is 19th.
When sorted by population density under age 18, Jefferson County is 5th, Kenton is 14th and Fayette is 20th.

Air Toxics Links of Interest

U.S. EPA Region 4 Main Air Toxics Web site: http://www.epa.gov/ttn/atw/
U.S. EPA Region 4 Air Toxics Web site: http://www.epa.gov/region4/air/airtoxic/index.htm
U.S. EPA Region 4 Toxic Release Inventory (TRI) Program: http://www.epa.gov/triinter/index.htm
Health Effects Notebook on Hazardous Air Pollutants: http://www.epa.gov/ttnatw01/hlthef/hapindex.html
Office of Air Quality Planning and Standards (OAQPS) Dose-Response Values for Risk Assessment: http://www.epa.gov/ttn/atw/toxsource/summary.html