Tier II Mutagenic Screening of 13 NIOSH Priority Compounds: Individual Compound Report; Methyl Bromide

摘要

Methyl-bromide (74839) was subjected to a tier II mutagenic test screening program. Screening included the following assays: unscheduled DNA synthesis (UDS) assay in human diploid fibroblasts with exposures of 3 hours and concentrations up to 70 percent in air; dominant lethal test in male rats and sperm abnormality tests in male mice with exposure to atmospheres containing 20 to 70 parts per million (ppm) methyl-bromide; cytogenetic test in male and female rats with bone marrow cells; and sex linked recessive lethal test in Drosophila-melanogaster with exposure to atmospheres of 20 or 70ppm for 5 hours. There was no increase in UDS in cells treated with methyl-bromide nor was the frequency of aberrant cells increased. There were no effects attributable to methyl-bromide in the dominant lethal test on pregnancy frequency, numbers of corpora lutea graviditatis or implantations, or the frequency of early deaths. Sperm abnormality frequency was not affected and sex linked recessive lethal mutation frequency was not increased as a result of methyl-bromide exposure. The author concludes that methyl-bromide was devoid of genetic effects.