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Energy and Environment Cabinet

Picture taken by Candy Montgomery

Division for Air Quality
Air Toxics Historical Background

Over the years, the Division for Air Quality (DAQ) has instituted many programs and measures to address criteria pollutants such as nitrogen dioxide (NOx), sulfur dioxide (SO2), carbon monoxide (CO) and particulate matter (PM).  Much improvement in air quality has been realized by those 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 Maximum Achievable Control Technology (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 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) now known as the Energy and Environment Cabinet 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 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.

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

Region 4 of the 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.

A spreadsheet produced by U.S. EPA consists of 736 counties for the eight states in Region 4.  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 of the score is based on risk calculations, 15 percent is based on disease incidence (influenced primarily by lifestyle choices and genetics, and some environmental issues), and 35 percent was based on population characteristics.  The NATA data is based on 32 Hazardous Air Pollutants and diesel PM.