Characterization of frequency-dependent responses of the vascular system to repetitive vibration.
Krajnak-K; Miller-GR; Waugh-S; Johnson-C; Li-S; Kashon-ML
J Occup Environ Med 2010 Jun; 52(6):584-594
OBJECTIVE: The current frequency weighting proposed in the International Standards oganization-5349 standard may underestimate the risk of injury associated with exposure to vibration >100 Hz. The goal of this study was to assess the frequency-dependent responses of the peripheral vascular system to repeated bouts of vibration. METHODS: The effects of exposure to vibration at 62.5, 125, or 250 Hz (constant acceleration of 49 m/s2) on vascular morphology, oxidative stress, inflammation, and gene expression were examined in the ventral tail artery of rats. RESULTS: Vascular responses indicative of dysfunction (eg, remodeling and oxidative activity) became more pronounced as the frequency of the exposure increased. CONCLUSION: Exposure to vibration frequencies that induce the greatest stress and strain on the tail (ie, >100 Hz) result in vascular changes indicative of dysfunction.
Vibration; Vibration-effects; Vibration-exposure; Standards; Animal-studies; Laboratory-animals; Oxidative-processes; Genes; Exposure-assessment; Exposure-levels; Laboratory-testing; Peripheral-nervous-system; Morphology; Neurovascular-disorders
Kristine Krajnak, PhD, Biostatics and Epidemiology Branch, NIOSH, 1095 Willowdale Road, MS2027, Morgantown, WV 26505
Journal of Occupational and Environmental Medicine