title: Sensitivity of Drosophila melanogaster to low concentrations of gaseous mutagens. II. Chronic exposures.
abstract: Sex-linked recessive lethal mutations were induced in Drosophila melanogaster males by gaseous 1,2-dibromoethane at concentrations ranging from 0.2 to 2 parts per million. Significant numbers of mutations could be induced at all these concentrations. Pronounced germ-cell sensitivity differences were observed. For low exposures, spermatids and spermatocytes were about 10--20 times more sensitive than spermatozoa. The dose-effect relation was linear below 60 ppm . h for the 3 cell types. At higher exposures, sterility prevented mutation detection in spermatocytes and in spermatogonia. The lowest effective exposure for spermatozoa was 18 ppm . h (0.25 ppm for 72 h). In spermatids, the lowest exposure tested, 2.3 ppm . h (0.2 ppm for 11 h) induced 4 times the spontaneous mutation rate. Therefore, using prolonged exposure periods one may be able to detect concentrations in the range of parts per billion. Thus, Drosophila appears suitable as a system for detecting very low concentrations of gaseous mutagens in industrial, agricultural and environmental atmospheres.
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D004331:Drosophila melanogaster / Q000235:genetics*; D015946:Ethylene Dibromide / Q000494:pharmacology*; D005804:Genes, Lethal; D005808:Genes, Recessive; D006842:Hydrocarbons, Brominated / Q000494:pharmacology*; D009153:Mutagens; D013997:Time Factors
chemical_list: D006842:Hydrocarbons, Brominated; D009153:Mutagens; D015946:Ethylene Dibromide