Criteria Pollutants and Hazardous Air Pollutants
To combat the amount and complexity of air pollution brought
about by industrial development and the use of motor vehicles, Congress passed a law in 1963 called the Clean Air Act.
The Clean Air Act http://www.epa.gov/air/caa/ requires EPA primarily to protect
and enhance the quality of air for public health and welfare and the environment.
To protect public health and welfare, the EPA sets National Ambient Air Quality Standards for six common air outdoor pollutants. These commonly found air pollutants (also known as "criteria pollutants") are found all over the United States, including Alaska. They are carbon monoxide (CO), lead (Pb), nitrogen oxides (NOx), particle pollution (often referred to as particulate matter or PM), ground-level ozone (O3), (a precursor of smog) and sulfur oxides (SOx).
These pollutants can harm the environment and threaten subsistence living (food and well-being). The criteria pollutants can also damage health and well-being of community members by adversely affecting cultural resources (living/non-living) and historical sites. Of the six common pollutants, particle pollution or particulate matter and smog are considered the most widespread for health threats. The EPA calls these pollutants "criteria" air pollutants because it regulates them by developing human health-based and/or environmentally-based criteria (western science-based guidelines) for setting permissible levels. The first set of limits are based on human health. These are called primary standards. The next set of limits intended to prevent environmental and property damage is called secondary standards.
Although the Clean Air Act is a federal law, each state attempts to carry out the act. In Alaska, air quality is monitored and regulated by the Alaska Department of Environmental Conservation (ADEC).
A larger set of pollutants, that are regulated but not as primary or “criteria” pollutants are called Hazardous Air Pollutants or HAPs. There are 188 of these pollutants in three categories: area sources, mobile sources and point sources. The EPA is required to regulate these many compounds. Hazardous air pollutants are chemicals which can cause adverse effects to human health or the environment. Included in the HAP pollutants are substances that cause cancer, neurological, respiratory, and reproductive problems.
Recent studies have detected HAPs at concentrations that warrant public health concern in many rural communities. Some areas of HAPs can be caused by both large and small sources like oil refineries, ships, and gas stations. A list of all 188 Hazardous Air Pollutants identified by the USEPA can be found at http://www.epa.gov/ttn/atw/orig189.html and more general information on HAPs may be found at http://www.scorecard.org/env-releases/hap/report-descriptions.tcl.