Workplace vibration causes physical ills

NEW ORLEANS, April 21 (UPI) -- A U.S. government scientist says job-related vibrations can result in biological injuries including vascular dysfunction that can cause loss of dexterity.

Kristine Krajnak of the National Institute of Occupational Safety and Health and her colleagues conducted what they say was the first study to directly link the different physical responses of tissue to various vibration frequencies with biological mechanisms underlying the development of vascular dysfunction.

The researchers said their findings support the importance of reducing job-related exposure to vibration.

Higher frequency vibrations -- those greater than 100Hz -- are smoother than the slower vibrations of approximately 63 Hz and therefore are less likely to cause users discomfort. But the researchers say their findings in research involving rats suggest exposure to both high and low frequencies cause different physiological responses, but both can affect the risk of developing vibration-induced peripheral vascular dysfunction.

Workers also might experience reductions in tactile sensitivity, grip strength and/or manual dexterity due to vibration exposure.

The study that include NIOSH biologists Stacey Waugh, Roger Miller and Claud Johnson, as well as biostatistician Michael Kashon was presented this week in New Orleans during the Experimental Biology 2009 meeting.