Ambient Air Toxic Monitoring

Toxic air pollutants, also called Hazardous Air Pollutants (HAPs), are known or suspected to cause adverse health or environmental effects. Most air toxics originate from human Activities such as vehicle emissions, factories, solvents, etc. The Clean Air Act (CAA) requires EPA to regulate emissions of toxic air pollutants from a published list of industrial sources referred to as "source categories." These sources must meet control technology requirements for toxic air pollutants. The EPA is required to develop regulations for all industries that emit one or more of the pollutants in significant quantities. Ambient Air Toxic Monitoring is required as part of the efforts to control air toxics pollutant which consists of both national and community-scale programs.

The Air Toxics Monitoring Steering Committee was established in 1999 to oversee the development of a national air toxics monitoring network. In 2002, the committee deployed the initial network consisting of 22 trend sites as follows:

Virginia's Air Toxics Monitoring Network (ATMN)

In 2002, The Department of Environmental Quality established three Air Toxic Monitoring Stations as part of the community-scale air toxics monitoring study. These stations are the State / EPA Region III cooperative-monitoring sites required by the special 103 Grant and the 105 Air Grant. Data collected from these sites will be used to characterize urban air toxic concentration and to assess the reasonableness of the National Air Toxics Assessment (NATA) inventory/modeling of 1999. The NATA estimates emissions and health risk information on 32-air toxics pollutants and diesel particulate matter (diesel PM) (list of 33 target compounds - PDF). EPA operates a web site, which contains current information concerning the NATA program and activities. This web site is located at http://www.epa.gov/ttn/atw/nata/.

Virginia's three ATMN sites are shown in the following table.

Sampling at the ATMN sites consists of ambient air samples. These samples take three different forms. The first is a canister sample of whole air. The second a DNPH treated cartridge and the third a quartz filter to collect particulate matter.

The sampling frequency is one 24-hour canister sample, one 24-hour DNPH coated Carbonyl cartridge, and one 24-hour Total Suspended Particulate (TSP) filter on every 6th day. The target pollutants are included in the list of 188 HAPs and some selected metals.

Canister samples are collected in a specially deactivated 6-liter canister. Integrated, whole air samples are collected using a mass flow controlled sampler. Canister samples are analyzed, at the Maryland Department of the Environment Air Lab, using Gas Chromatography and a Mass Spectrometer (GC/MS) by EPA Method TO14/15. A list of TO14/15 target compounds may be viewed by clicking on the following link. (TO14/15 target compounds - PDF)

Carbonyl cartridges are analyzed at the Air Management Laboratory of Philadelphia for 7 Carbonyl compounds using liquid chromatography by EPA method TO-11. These target compounds may be viewed by clicking on the following link. (Carbonyl target compounds - PDF)

TSP filters are weighed and analyzed by the West Virginia Air Laboratory for some selected metals. The target compounds may be viewed by clicking on the following link. (target metals - PDF)

The above laboratories have been designated as the EPA region III laboratories for their respective analysis.

Additional information:

The Plain English Guide to the Clean Air Act (CAA) is a web site maintained by the EPA. This web site can be found at http://www.epa.gov/oar/oaqps/peg_caa/pegcaain.html. This web site attempts to demystify the CAA and use plain English to explain the requirements set forth in the CAA.

Methods of analysis my be viewed by clicking on the following links:

• Volatile Organic Compounds (VOCs) by TO-14 (PDF)
• Volatile Organic Compounds (VOCs) by TO-15
• Carbonyls by TO-11A
• TSP Metals by IO-3.5

Questions concerning any variations to the above methods would need to be directed to the laboratory performing the specific analysis located below.

Dennis Sosna
City of Philadelphia
Department of Public Health
Carbonyl Group
Air Management Services Laboratory
1501 E. Lycoming Street
Philadelphia, PA 19124

Walter Cooney
Maryland Department of the Environment
Air and Radiation Management Administration
1800 Washington Blvd., STE 110
Baltimore, Maryland 21230-1721

Todd Jackson
West Virginia Department of Environmental Protection
Division of Air Quality
Guthrie Lab
4900 Brenda Lane
Bldg. 14
Charleston, WV 25312

Questions concerning the DEQ Ambient Air Toxics Monitoring Program should be directed to:

Baxter Gilley
Office of Air Quality Monitoring
4949-C Cox Road
Glen Allen, VA 23060
Voice: 804-527-5188
Fax: 804-527-5160
Email: bjgilley@deq.virginia.gov