The use of Drosophila to estimate the possibility of genetic hazard from ultrasound irradiations.

Flies of the species Drosophila melanogaster have been irradiated with 1 MHz ultrasound at intensities of 0-05-2 W cm-2. The flies were immersed in water and rotated in the ultrasound field to ensure that they were adequately exposed to the radiation. Immersion and rotation alone were not found to impair subsequent survival and fertility of the flies. At the higher intensities of irradiation, the flies were found to be killed in direct proportion to the duration of the irradiation. However, large-scale breeding experiments with flies surviving irradiation showed that no significant increase in the frequency of recessive lethal mutation (Muller 5 system) and chromosomal non-disjunction (Clark-Sobels system) had occurred. Taken with other recent studies, this result suggests there is little risk of genetic damage to multicellular organisms from ultrasound irradiations at frequencies and intensities currently used in medical practice.