Hazardous Air Contaminants

What Are Hazardous Air Contaminants?

Hazardous air contaminants, or air toxics, refers to the 290 hazardous air contaminants (HACs) listed in the Vermont Air Pollution Control Regulations, Appendix B that are known or suspected of causing cancer or other serious health effects if inhaled. The pollutants listed as HACs include industrial chemicals, solvents, metals, pesticides, and combustion by-products. There is growing concern nationally over levels of hazardous air pollutants in the air.

The most significant hazardous air contaminants in Vermont include ten pollutants which exceed Vermont’s Hazardous Air Contaminant Standards and one which nearly does. These standards were established to minimize health risks from exposures to these pollutants.

Hazardous Air Contaminants in Vermont

Information from both the state's air toxics monitoring program and the National Air Toxics Assessment (NATA) show that hazardous air pollutants or "air toxics" exist in our air at potentially unhealthy levels. Air toxics come from a variety of sources including automobiles and diesel trucks, small sources such as gas stations, home heating systems and dry cleaners, and industrial sources.

State Actions

The Vermont legislature first instituted air pollution control laws in 1967. During the 1980’s, growing concern over the potential health and environmental effects of unregulated air toxics led to the development of regulations. In 1993 the program was strengthened through establishment of the Hazardous Air Contaminant Monitoring Program, adoption of amended regulations, and appointment of an 11-member Toxicological Advisory Committee (TAC). The TAC released its Air Toxics Report in February 1998. This report reviewed and affirmed the methodology for deriving the Hazardous Ambient Air Standards (HAAS) for the three categories of compounds listed in Appendix C of the 1993 amended regulation; Category I (potentially carcinogenic), Category II (non-carcinogens with potential chronic/systemic effects due to long-term exposure) and Category III (non-carcinogens having short-term irritant effects).

Since then Vermont has implemented numerous programs and activities to control the emission of air toxics into the atmosphere. These efforts include a motor vehicle inspection and maintenance program, and a low emission vehicle program. In addition, Vermont state law prohibits the open burning of household refuse and construction debris. Vermont also has a comprehensive air pollution permitting program that places stringent limitations on emissions coming from manufacturing sources and utilities. Finally, Vermont requires most point sources of air pollution to register their annual emissions. This enables the AQCD to estimate the total emissions of toxic pollutants to the atmosphere in Vermont annually, identify sources of concern, and develop policies and programs to reduce the risk posed by these emissions.

What Can I Do to Help?

The best way to get started is to become informed. Knowing which home heating systems, automobiles, and consumer products emit the least amount of hazardous air pollution will help you make choices for cleaner air. Understanding how your car's pollution control systems work and making sure they are maintained will reduce the amount of toxics released into the air. Simply reducing consumption of gasoline and other fossil fuels is a tremendous help. Local air quality forecasts are available as well. For more tips check out Reduction Efforts.