Estimation of genome damage after exposure to ionizing radiation and ultrasound used in industry.

The application of ionizing radiation in industry for nondestructive testing entails a specific framework of working conditions that include field work, facilities with different radioactive sources, maintenance thereof without halting production, use of nonionizing radiation, and exposure to chemical agents. The present study gives an estimation of recent genome damage in two groups of subjects using chromosome aberration assay and micronucleus assay. The first group was exposed to (192)Ir and the second was simultaneously exposed to (192)Ir and ultrasound. The results show that both groups had higher values of chromosome aberrations and micronucleus frequency than controls. The group of examinees exposed both to (192)Ir and ultrasound had significantly more chromatid breaks, acentric fragments, and dicentric chromosomes, and had a significantly higher frequency of micronuclei than subjects exposed to (192)Ir only. The study suggests that the detected differences in the genome damage may be attributed to the action of ultrasound. This study confirms the dosimetry data for ionizing radiation, which indicate that the methods used in industrial radiography and the usage of nonionizing radiation entail an increased health risk. In the absence of personal dosimeters for nonionizing radiation and chemical agents, biomonitoring provides reliable parameters for estimation of genome damage and may lead to improvements in working conditions and radiation safety programs. Copyright 2000. Wiley-Liss, Inc.