Final answer:
The six criteria pollutants include Carbon Monoxide, Ground-level Ozone, Nitrogen Dioxide, Sulfur Dioxide, Lead, and Particulate Matter, each having major sources such as mobile sources, combustion processes, and industrial activities.
Step-by-step explanation:
Criteria Pollutants and Major Sources
The six criteria pollutants identified by the EPA and their major sources are as follows:
- Carbon Monoxide (CO): Mainly emitted from mobile sources like cars and trucks due to incomplete combustion of fuel.
- Ground-level Ozone (O3): Formed by the reaction of sunlight, heat, nitrogen oxides (NOx), and volatile organic compounds (VOCs), with significant contributions from industrial facilities, electric utilities, and vehicle exhaust.
- Nitrogen Dioxide (NO₂): Produced from high-temperature combustion, such as in vehicle engines and power plants.
- Sulfur Dioxide (SO₂): Primarily resulting from the combustion of fossil fuels in power plants and other industrial facilities.
- Lead (Pb): Emitted from ore and metal processing and, to a lesser extent, from aviation gasoline used in piston-engine aircraft.
- Particulate Matter (PM): Arises from a variety of sources including combustion processes, road dust, and industrial activities, characterized by their size as coarse particles (PM10) or fine particles (PM2.5).
Each criteria pollutant has been associated with various health risks and environmental impacts, affecting the respiratory, cardiovascular, and nervous systems.