Particulate Matter (PM)
COARSE PARTICULATE MATTER (PM10) STANDARDS AND AGRICULTURE
WHAT EPA IS DOING
- On Dec. 14, 2012, the U.S. Environmental Protection Agency (EPA) strengthened the nation’s air quality standards for fine particle pollution to improve public health protection by revising the primary annual PM2.5 standard to 12 micrograms per cubic meter (µg/m3) and retaining the 24-hour fine particle standard of 35 µg/m3. The agency did not change the standard for coarse particles (PM10).
- Strong scientific evidence provides strong support for retaining the existing PM10 heath standard to provide public health protection against coarse particles. That standard, which has been in place since 1987, is a 24-hour standard of 150 micrograms per cubic meter, which has been in place for 25 years – since 1987. The standard is what is known as a “one-expected-exceedance” standard, meaning that an area is violating if it exceeds the standard more than once a year, on average, over a three-year period.
- As part of this action, EPA also finalized updates and improvements to the nation’s PM2.5 monitoring network. The agency did not make changes to the coarse particle monitoring network.
- EPA is scheduled to complete the next review of the PM standards in 2017.
WHAT THE EXISTING PM10 STANDARDS HAVE MEANT FOR AGRICULTURE
- Protecting and improving the nation’s air quality is the work of a federal-state partnership established in the Clean Air Act. EPA issues national standards and designates the “nonattainment areas” that must reduce pollution in order to meet them, generally basing these designations on data collected at air quality monitors. States then determine what those pollution reduction steps will be and outline those steps in plans known as “state implementation plans.”
- Like all national air quality standards, the existing PM10 standards set the amount of PM10 pollution allowed in the outdoor air. But the standards themselves do not establish emission control requirements for any particular industry, including agriculture. Each state determines how to reduce a nonattainment area’s pollution to meet the standards in a way that makes the most sense for that area.
- The vast majority of states have not required the agriculture industry to take any actions that require PM10 emission reductions; focusing their efforts to reduce PM10 on sources such as industrial processes, and construction and demolition.
- Because agricultural emissions are a larger portion of overall PM10 emissions in some nonattainment areas in California and Arizona, those states are addressing PM10 from agriculture by incorporating conservation management practices developed with growers and USDA into PM10 implementation plans for those nonattainment areas.
- Similarly, EPA requires PM10 monitoring in areas with populations of 100,000 or more, with more monitors required in areas of higher population and with higher PM10 levels. States have the discretion to site additional PM10 monitors to meet their own clean air objectives.
COARSE PARTICLES AND HEALTH
- A particle that is 10 micrometers in diameter is extremely small and can get past the respiratory system’s natural defenses (the nose and throat). For comparison, the diameter of an average human hair is about 50-70 micrometers – five to seven times larger than the largest coarse particle.
- Scientific studies have linked exposure to coarse particles to a variety of health problems, including hospital admissions for heart disease, hospital admissions and doctors’ visits for respiratory diseases, increased respiratory symptoms in children and premature death in people with heart or lung disease.
FOR MORE INFORMATION:
- To read the revised standards and additional fact sheets, visit http://www.epa.gov/pm/actions.html