Particulate Matter Fact Sheet

Particle pollution, called particulate matter or PM, is a combination of fine solids and aerosols that are suspended in the air we breathe. Some PM facts at a glance:

• PM from diesel exhaust is one of the most dangerous pollutants
• PM not only bypasses the body's defense mechanisms and becomes embedded in the deepest recesses of the lungs, but can also disrupt cellular processes
• Population-based studies in hundreds of cities in the U.S. and around the world have demonstrated a strong connection between elevated particulate levels and premature deaths, hospital admissions, emergency room visits and asthma attacks
• Groundbreaking long-term studies of children's health conducted in California have demonstrated that particulate pollution may significantly reduce lung function growth in children₁ and that these effects are permanent₂

[1] Peters et al. 1999, Avol et al. 2001, Gauderman et al. 2002
[2] Gauderman et al. 2004

"Black Carbon" Facts

Black carbon, a form of particulate air pollution most often produced from biomass burning, cooking with solid fuels and diesel exhaust, has a warming effect in the atmosphere 3 to 4 times greater than prevailing estimates, according to scientists in an upcoming review article in the journal Nature Geoscience.