EPA PM 2.5 monitoring overview, Sept 2001

NYC 9/11 Public Portal Document

• PM 2.5 Fact Sheet Page 1 of 3 f EnvtnnaiGtiUil Agency EPA Response to September 11 Contact Us Search: j @ Advanced Search I Response to 9-11 > Monitoring Data > PM 2.5 Fact Sheet Monitoring Summaries Monitoring Data PM Fact Sheet Frequently Asked Questions What is Particulate Matter (PM) Pictures EPA Press Releases • Airborne particulate matter (PM) consists of many different substances suspended How You Can Help in air in the form of particles (solids or liquid droplets) that vary widely in size.

• The particle mix in most U.S. cities is dominated by fine particles (less than 2.5 micrometers in diameter) generated by combustion sources with smaller amounts coarse dust (between 2.5 and 10 micrometers in diameter). The fine particles resulting from the collapse of the World Trade Center (WTC) are largely due to the smoke from combustion of fuels and other combustible materials. The coarse dust in the WTC area is largely due to the removal of building debris and rubble.

Health Effects of Dust and Smoke

• Dust and smoke may irritate healthy people's eyes, nose, throat, and lungs, and might cause more serious problems in sensitive populations.

• Because dust and smoke are mixtures of different chemicals with different sizes, not everyone will experience the same effects.

• Most healthy adults and children will recover quickly from short-term dust and smoke exposures and will not suffer long-term consequences.

• In general, the long-term risk from short-term exposures to dust and smoke is low.

Sensitive Populations

• Certain sensitive populations, listed below, are susceptible to more severe symptoms, including cough, phlegm, wheezing, shortness of breath, bronchitis, increased asthma attacks, and aggravation of lung or heart disease. Exposure to fine particles (e.g. smoke) is of particular concern, and can be associated with several serious health effects. Some sensitive people might experience health problems after even short exposures to fine particles, such as several hours or a day.

- Individuals with asthma and other respiratory diseases. Levels of pollutants that might not affect healthy people might cause breathing difficulties for people with asthma or other chronic lung diseases, especially children. Individuals with emphysema and chronic bronchitis may also experience a worsening of their conditions because of exposure to dust and smoke. Studies have linked particulate matter pollution to increased risk of hospitalizations for respiratory disease, asthma attacks, and respiratory mortality.

- Individuals with cardiovascular disease. People with heart disease

http://www.epa.gov/enviro/nyc/pm25/pm_fact_sheet.html 3/25/02

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