Health and Environmental Effects Research
EPHD Scientists' Paper on Ozone Inhalation Research Published in EHP
In early December, Environmental Health Perspectives (EHP) published a manuscript entitled “Overt and Latent Cardiac Effects of Ozone Inhalation in Rats: Evidence for Autonomic Modulation and Increased Myocardial Vulnerability,” by Aimen K. Farraj and colleagues at the NHEERL Environmental Public Health Division (EPHD). Dr. Farraj and his co-authors demonstrated previously undescribed findings with a single ozone exposure, including alterations in myocardial conduction and repolarization (i.e., PR prolongation and ST depression) and cardiac arrhythmia, that are likely mediated by autonomic modulation (increased parasympathetic tone). In addition, exposure to low ozone levels caused subclinical effects (increased sensitivity to cardiac arrhythmia) that were manifested only when triggered by a stressor, suggesting that health effects of ambient levels of air pollutants may be insidious and potentially underestimated. These findings have regulatory implications because they suggest that the wealth of knowledge we have on the direct effects of ozone may not inform us fully of the complex cardiopulmonary response profile of this oxidant. Collectively, these findings provide new insight into the effects and mechanisms of ozone toxicity.
Citation: Aimen K. Farraj, Mehdi S. Hazari, Darrell W. Winsett, Anthony Kulukulalani, Alex P. Carll, Najwa Haykal-Coates, Christina M. Lamb, Edwin Lappi, Dock Terrell, Wayne E. Cascio, and Daniel L. Costa. Overt and Latent Cardiac Effects of Ozone Inhalation in Rats: Evidence for Autonomic Modulation and Increased Myocardial Vulnerability, Environmental Health Perspectives (published electronically ahead of print on December 2, 2011).