CYTOGENETIC ANALYSES OF THE IN-VITRO AND IN-VIVO RESPONSES OF MURINE CELLS TO PEROXYACETYL NITRATE (PAN)

Peroxyacetyl nitrate (PAN) is one of a class of common air pollutant f ormed by the action of sunlight on volatile organic compounds and nitr ogen oxides. PAN has been shown to be a bacterial mutagen. To determin e if PAN can cause DNA damage in mammalian cells, we exposed murine pe ripheral blood lymphocytes (PBLs) to various volumes of PAN in vitro a nd analyzed the cells for chromosome aberrations (CAs), sister chromat id exchanges (SCEs), and DNA damage using the single cell gel (SCG) as say. At in vitro concentrations of PAN that were cytotoxic (inhibited cell division), an increase in DNA damage was noted in the SCG assay. At lower exposure levels that permitted cell division, no increases in SCEs, CAs, or DNA damage were evident. For in vivo studies, male mice were exposed nose-only by inhalation for 1 h to 0, 15, 39 or 78 ppm P AN, and their lung cells removed and cultured for the scoring of SCEs and CAs. In addition, PBLs and lung cells were analyzed by the SCG ass ay. No dose-related effects were found in any of the assays. These dat a indicate that PAN does not appear to be a potent clastogen or DNA da maging agent in mammalian cells in vivo or in vitro.