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January 25, 2006

New Center Established to Study Health Effects of Air Pollution

$8 Million EPA STAR Grant Establishes Particulate Matter Research Center at Johns Hopkins Bloomberg School of Public Health

The Johns Hopkins Bloomberg School of Public Health received a $8 million Science to Achieve Results (STAR) grant from the U.S. Environmental Protection Agency (EPA) to establish a new center to study the health effects of particulate matter—the microscopic particles that pollute the air. The Johns Hopkins Particulate Matter Research Center will map the health risks of particulate matter across the United States over the next five years, by analyzing national databases on air pollution, mortality and hospitalization. Researchers will also conduct detailed monitoring and collect particulate matter samples nationwide to determine how their makeup affects pulmonary and cardiovascular health.

Particulate matter, also referred to as particle pollution, is an airborne mixture of solid particles and liquid droplets. The solid particles come in numerous shapes and sizes and may be composed of many different chemical components. Fine particles, defined as 2.5 micrometers or less in size (approximately 1/30th the size of a human hair), can penetrate deep into the body’s respiratory system. Airborne particulates come from a variety of sources, including coal-burning power plants, factories, construction sites, cars, trucks, buses, tilled fields, unpaved roads, stone crushing and the burning of wood. Other particles may be formed in the air when gas emitted from burning fuels reacts with sunlight and water vapor.

Previously, researchers at the Bloomberg School of Public Health demonstrated an association between particulate matter levels and mortality nationwide. Other research studies at the School have shown associations between particulate matter and premature death from cardiopulmonary causes, hospitalization for respiratory or cardiovascular diseases and exacerbation of respiratory diseases.

Jonathan Samet

Jonathan Samet, MD

“Our air is full of particulate matter, whether it comes from large power plants or from motor vehicle traffic in our own neighborhoods. Particulate matter pollution is a well established problem, but we want to find out which particles are the most injurious to health so that their sources can be controlled,” said Jonathan Samet, MD, director of the new center and chair of the Department of Epidemiology at the Bloomberg School of Public Health.

In addition to the Hopkins group, the Johns Hopkins Particulate Matter Research Center will collaborate with colleagues from the University of Chicago, University of Maryland, Yale School of Forestry & Environmental Studies, Georgia College & State University and the Lamont-Doherty Earth Observatory at Columbia University.

The grant is one of five totaling $40 million awarded to universities across the nation to establish five centers to study the particulate matter component of air pollution. The particulate matter centers will integrate multiple scientific disciplines to advance understanding of how to reduce the health impacts of particulate air pollution. Clinical scientists will work with health physicists, engineers, statisticians, epidemiologists and toxicologists to determine the characteristics and sources of particles and their most severe effects. The five research centers will focus on human susceptibility, mechanisms of health effects, exposure-response relationships and the cross-cutting issue of linking health effects with particulate matter sources and components. The four additional grants were awarded to Harvard University, the University of Rochester, the University of California at Davis and the University of California at Los Angeles.

“These research centers will further improve our understanding of how and in what manner particulate matter negatively impacts human health. While the United States has made noticeable progress over the last four decades in reducing air pollution, substantial concern still remains about the health effects of particle pollution,” said Donald S. Welsh, EPA mid-Atlantic Regional Administrator.

Media contact for the Environmental Protection Agency: Mike Frankel at 215-814-2665.
Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Lowe or Tim Parsons at 410-955-6878 or