Farhang Haddad - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad
Vajiheh Golami - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad
Maliheh Pirayesh Shirazi Nejad - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad

Due to the wide range of applications for ozone and its increasing use for medical and industrial purposes, studying its effects has become a very important line of research. The ozone has been suspected to be a carsinogen. Because of the increasing use of ozone, the human could be more and more exposed to this gas. In this study the effects of ozone inhalation on chromosomes and its clastogenic consequences have been investigated using in vivo micronucleus assay in bone marrow cells of treated rats.Animals were treated for 6 hours a day at 3 ppm of ozone during 10 consecutive days. The micronucleus assay was performed immediately and 11 days after the last exposure. The frequency of micronucleated polychromatic erythrocyte of bone marrow (MNPCE) increased in both groups compared to the control. Such increase confirmed the clastogenic effects of ozone. The elevated frequency of MNPCE did not decrease after 11 days of the last ozone exposure.Results indicate that ozone inhalation could induce persistent chromosomal damages even to bone marrow cells which were not in direct contact to it. Also, once more, the results confirmed the usefulness of the micronucleus assay in toxicological studies.

ozone inhalation, micronucleus assay, chromosomes