Volume 9 of Chemical Mutagens consists mainly of chapters discussing the development and validation of short-term assays to detect the mutagenic effects of environmental chemicals. These chapters include an assay with the grasshopper neuroblast, a comparison of mutagenic responses of human lung-derived and skin-derived diploid fibroblasts, a forward-mutation assay in Salmonella, a multigene sporulation test in Bacillus subtilis, a specific locus assay in mouse lymphoma cells, a study of the induction of bacteriophage lambda, and the granuloma pouch assay. In addition, there are two chapters on the identification of mutagens in cooked food and in human feces. Frederick 1. de Serres Research Triangle Park, North Carolina vii Contents Chapter 1 The Grasshopper Neuroblast Short-Term Assay for Evaluating the Effects of Environmental Chemicals on Chromosomes and Cell Kinetics 1 Mary Esther Gaulden, Jan C. Liang, and Martha J. Ferguson 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. Embryo Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. 1. Species. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. 2. Origin of Colonies . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. 3. Life Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. 4. Colony Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 6 2. 5. Pathology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2. 6. Allergy to Grasshoppers . . . . . . . . . . . . . . . . . . . . . . 14 3. Grasshopper Egg, Embryo, and Cells . . . . . . . . . . . . . . . . . 14 3. 1. The Egg Shell and Membranes . . . . . . . . . . . . . . . . . 14 3. 2. Embryonic Development . . . . . . . .. . . . . . . . . . . . . . 17 3. 3. Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4. Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4. 1. Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4. 2. Preparation of Embryos for Cell Analysis . . . . . . . . . 34 4. 3. Analysis of Mutagen Effects. . . . . . . . . . . . . . . . . 40 . . . 5. Response of the Grasshopper Neuroblast to Mutagens . . . . 50 5. 1. Reproducibility of Data . . . . . . . . . . . . . . . . . . . . . . . 50 5. 2. Radiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5. 3. Chemical Mutagens . . . . . . . . . . . . . . . . . . . . . . . . .