Health and Environmental Effects Research
NHEERL Scientists Release NEAR-Roadway Study Results Focused on Cardiopulmonary Toxicity of Roadside PM
There is increasing evidence that exposure to traffic-related air pollutants is associated with the incidence and severity of cardiopulmonary disease. Researchers in NHEERL and NRMRL recently have reported on the toxicity of airborne particles collected next to a highway in Raleigh, NC ("Comparative Toxicity of Size-Fractionated Airborne Particulate Matter Collected at Different Distances from an Urban Highway," available at http://www.ehponline.org/members/2009/0900730/0900730.pdf). The study included collection and chemical analysis of each of three size fractions of particles (coarse, fine, and ultrafine) collected at two distances (10 and 275 m) from the highway, with subsequent toxicity testing in mice. There were no differences in toxicity effects for an equal mass of particles collected at the two locations; however, greater amounts of particles were collected next to the road. Whereas the coarse particles induced pulmonary inflammatory responses in mice, the same mass of ultrafine particles caused cardiac injury. The results show, for the first time, that different sized particles collected from the same airshed can affect different organ systems and support the epidemiological findings that smaller particles affect the cardiovascular system, whereas larger particles impact the lung. Dr Seung-Hyun Cho, a joint postdoctoral ORISE fellow mentored by Dr. Ian Gilmour (EPHD/NHEERL and Dr. Bill Linak (APPCD/NRMRL), was the lead author of the study, in collaboration with Dr. Richard Baldauf (NRMRL), Dr Haiyan Tong (NHEERL), and ORD's near-roadway team.