INDUCTION OF CHROMOSOME-ABERRATIONS IN PERIPHERAL-BLOOD LYMPHOCYTES AFTER SHORT-TIME INHALATION OF NITRIC-OXIDE

Introduction: inhalation of nitric oxide (INO) leads to vasodilation o f pulmonary vasculature in ventilated regions of the lung. The clinica l use of INO, although not formally approved as a drug, is widespread. NO may rapidly form nitrogen dioxide (NO2) in an oxygen containing ga s mixture. NO2 has been shown to induce chromosome aberrations and mut ations in both animal and bacterial test systems. We investigated whet her a 2-h exposure to NO would increase frequencies of cells with chro mosome aberrations in peripheral blood lymphocytes of human volunteers . Methods: 10 volunteers were exposed to inhaled NO 40 parts per milli on (ppm) for 2 h, Pre-and post-exposure blood samples were analysed. R esults: no statistically significant differences (p less than or equal to 0.05) in chromosome aberrations were observed between pre-and post -exposure samples. Conclusion: no detectable increase of chromosome ab errations in human peripheral blood lymphocytes after 2 h of NO-inhala tion 40 ppm was found. (C) 1998 Elsevier Science B.V. All rights reser ved.