Note: This is the fastest and easiest method to
"detect" that there is a toxic effect occurring within the respiratory tract. It
will not tell you what exactly is going wrong, but once you detect you can investigate
further using other methods. Since the method is non-invasive and requires no anesthesia
it can be used repeatedly in chronic studies. See: Ellakkani, M.A., Alarie, Y.,Weyel, D.
and Karol, M.H. Chronic pulmonary effects in guinea pigs from prolonged inhalation of
cotton dust. Toxicol. and Appl. Pharmacol. 88, 354-369, 1987.