November 19, 2008

An estimated 50,000 people die in the United States each year due to breathing fine particles in outdoor air. Previous instruments developed to measure exposure to fine particles have proven expensive, intrusive, and cumbersome. These tools, called active samplers, require a pump that attaches to the subject’s waistband and a source of electrical power. Researchers desired a more effective way to measure exposure to fine particles. David Leith, ScD, Professor, Environmental Sciences and Engineering (ESE), UNC Gillings School of Global Health, together with Jeff Wagner, a PhD student in ESE, developed a new sampler. Dr. Leith’s research interests include factors that affect the generation and release of air contaminants, methods to measure the concentration and properties of air contaminants in outdoor air and in the workplace, and engineered methods to remove these contaminants from waste gas streams.

 Created here at the School, the new device, called the UNC passive aerosol sampler, is about the size and weight of a nickel and attaches to the collar or lapel of a shirt. It requires no pump or electrical power because it collects particles by natural processes such as gravity and diffusion. Importantly, the UNC sampler costs much less than the active samplers it replaces. The UNC passive aerosol sampler is now commercially available through R. J. Lee Group, Inc. in Pittsburgh. Researchers at other universities, at the U.S. EPA, and at the National Institute of Environmental Health Sciences are using the UNC passive aerosol sampler. As an example that local is global, the research and design accomplished in the School to create this sampler will help with exposure assessment work throughout the world. The samplers will enable School researchers working in the United Arab Emirates to characterize particle exposures more effectively. Most research on fine particles has focused on how they affect health. Dr. Leith believes that we must now direct some research on fine particles toward developing cost-effective methods to control them. Unfortunately, no research funds for fine particle control are available in the federal budget. Dr. Leith’s hopes that data collected by the UNC passive aerosol sampler will help inform public policy to improve the air we breathe.

Last updated November 19, 2008


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