Propyl ether. II. Pulmonary irritation and anaesthesia.

After cessation of the sensory irritation response, described in part one (Nielsen et al. 1985), a mixed response due to pulmonary irritation and anaesthesia appeared, resulting a decrease in respiratory rate and tidal volume. The corresponding thresholds were 1490 p.p.m. and 1280 p.p.m., respectively, obtained from the last half hour of a four hours exposure period. As the decrease in respiratory rate and tidal volume was found to be correlated, the per cent decrease in respiratory minute volume could be approximated from the square of the respiratory frequency. A threshold limit value (TLV) about 100 p.p.m. based on pulmonary irritation and anaesthesia was proposed. No impurities in the technical grade ether influenced the responses.