<b>Studies on SO₂, NO₂ and NH₃: Effect on Ciliary Activity in Rabbit Trachea of Single in Vitro Exposure and Resorption in Rabbit Nasal Cavity</b>

Abstract

Abstract D alhamn , T. and J. S jöholm . Studies on SO 2 , NO 2 and NH 3 : effect on ciliary activity in rabbit trachea of single in vitro exposure and resorption in rabbit nasal cavity . Acta physiol. scand. 1963. 58 . 287—291. — One of the factors which determine the toxicity of pulmonary irritant gases, etc., presumably is their action on the ciliated epithelium of the respiratory tract. The degree to which such gases are resorbed in the mucous layer of the respiratory passages must also be taken into ac‐count when hygienic limits and allied questions are discussed. The present paper illustrates these two factors, viz., ciliostatic action and resorption, by experiments with three common respiratory irritant gases — sulphur dioxide, nitrogen dioxide and ammonia. As regards concentration required to arrest tracheal ciliary activity in vitro , the three gases varied considerably. The degree of resorption in the upper respiratory tract also showed wide variations. It seems probable that a gas which even in low concentration rapidly impairs ciliary activity and which is resorbed to a relatively slight degree can penetrate deeper into the bronchial tree and thus, on the stated assumptions, be more toxic than gases with the reverse characteristics.