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CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS
Citation:
Watkinson, W P., J. P. Nolan, D. W. Winsett, U P. Kodavanti, M. Schladweiler, L. C. Walsh, E. R. Lappi, D. Terrell, R. Slade, A. D. Ledbetter, D L. Costa, AND L. B. Wichers. CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS. Presented at Society of Toxicology 42nd Annual Meeting, Salt Lake City, Utah, March 9-13, 2003.
Description:
CONCENTRATED AMBIENT PARTICULATE STUDIES IN HEALTHY AND COMPROMISED RODENTS. WP Watkinson1, LB Wichers2, JP Nolan1, DW Winsett1, UP Kodavanti1, MCJ Schladweiler1, LC Walsh1, ER Lappi1, D Terrell1, R Slade1, AD Ledbetter1, and DL Costa1. 1USEPA, ORD/NHEERL/ETD/PTB, RTP, NC, USA;2UNC SPH, Chapel Hill, NC, USA
Epidemiological studies have reported a consistent association between exposure to higher concentrations of ambient particulate matter (PM) and excess cardiopulmonary-related morbidity and mortality. To further examine this phenomenon, we exposed various rodent models of cardiopulmonary dysfunction to Concentrated Ambient Particulates (CAPs) and monitored changes in indices of cardiopulmonary function and damage. Animal models used included young (3 mo) Spontaneously Hypertensive (Y-SH), old (11 mo) Spontaneously Hypertensive (O-SH), and healthy (SD) and monocrotaline-treated Sprague-Dawley (MCT-SD) rats. Subsets of animals were implanted with radiotelemeters to monitor (5-min intervals?24h/d) electrocardiogram (ECG), heart rate (HR), systemic blood pressure (BP), and core temperature (Tco.). Exposure protocols for Y-SH rats were either Continuous (4h/d?2?3d/wk?11wk) or Intermittent (4h/d?1d/wk?11wk) while SD, MCT-SD, and O-SH were exposed 4h/d?2?3d/wk?1wk. Pulmonary function tests (Buxco Electronics) were performed on all animals before, during, and after exposures. At the termination of the study, animals underwent bronchoalveolar lavage (BAL) and the BAL fluid was examined for biochemical indices of pulmonary damage and inflammation. Heart and lung tissues were harvested for histological and morphological analyses. PM exposure concentrations ranged from 135?1600 g/m3. In general, despite the variety of exposure protocols and compromised animal models used, these studies demonstrated minimal adverse effects on cardiopulmonary and thermoregulatory function in cardiopulmonary-compromised rats after exposure to CAPs. Furthermore, these studies underscore the inherent complexities of conducting toxicology studies using "real-world" exposure atmospheres.
(Abstract does not represent USEPA policy. This research was supported in part by EPA CT826513.)