Chief Causes for Concern

Particulate Matter:

• Is associated with serious health effects that result in increased hospital admissions and emergency room visits for people with heart and lung disease. Health problems for sensitive people can get worse if they are exposed to high levels of PM for several days in a row.
• Is associated with work and school absences.
• Is the major source of haze that reduces visibility in many parts of the United States, including our National Parks, and causes erosion and staining of structures including culturally important objects such as monuments and statues.
• Settles on soil and water and harms the environment by changing the nutrient and chemical balance.