Chromosomal damage in air crew members of international flights. A preliminary report

Air crew members of international flights are exposed to ionizing radiation s originated from the collision of cosmic particles with atoms of the atmos phere. The degree of exposure varies according to the altitude, latitude, a nd solar activity. The cytogenetical analysis showed a significant increase of dicentric chromosomes (14.5 +/- 0.76 per 1,000 cells) in active air cre w members as well as in retired air crew members (7.5 +/- 0.59 per 1,000 ce lls) in relation to controls (0.5 +/- 0.05 per 1,000 cells). In active memb ers the frequency of ring chromosomes was also increased (2.0 +/- 0.31 per 1.000 cells) but not found in retired crew members. These observations sugg est a high degree of exposure to ionizing radiations of air crew personnel. Consequently, the cytogenetic follow-up of air crews chronically exposed t o low radiation doses is an open field for further investigations.