Study of carcinogenicity and toxicity of inhaled 1,2-dibromomethane in rats treated with disulfiram.
Wong-LC; Winston-JM; Hong-CB; Hagensen-J
Midwest Research Institute, Biological Sciences Division, 1979 Feb; :1-100
The carcinogenicity of chronic inhalation of ethylene-dibromide (106934) (EDB) vapor with ingestion of disulfiram (97778) was studied in Sprague-Dawley rats. Four groups of animals received either control air and control diet; control air and 0.05 percent disulfiram; 20 parts per million (ppm) EDB and control diet; or 20ppm EDB and 0.05 percent disulfiram. Dying rats that received EDB and disulfiram were pale anemic, however, dying rats from other treatment groups were not. Rats receiving EDB alone and those receiving EDB and disulfiram had high mortality rates compared with control and disulfiram treated rats. The mortality rate for EDB and disulfiram treated rats was 75 percent for males and 94 percent for females. Rats administered EDB alone had a mortality rate of 9 percent at the end of 12 months. At the end of 18 months, the mortality rate was 90 percent for male rats and 77 percent for female rats. The control air and control diet group and the disulfiram group had mortality rates of 11.5 and 9.3 percent at the end of 18 months. After 18 months rats receiving control diet and receiving control air and control diet and those exposed to 20ppm EDB and control diet. By the end of the 13 months period of EDB and disulfiram treatment, all animals either died or were terminated because of their moribund state. Rats receiving EDB and disulfiram treatment had low hematocrit, hemoglobin and red blood cell counts, and females were more affected than males. EDB treatment alone caused increased liver and kidney weights. Ninety percent of male rats receiving EDB and disulfiram suffered from testicular atrophy and had higher incidences of tumors than rats receiving only EDB. The authors suggest that the high mortality rates in rats receiving EDB and disulfiram are a result of earlier development of tumors in these rats or of the toxicity of the combined treatment.
NIOSH-Author; Cancer; Laboratory-animals; Chronic-toxicity; Air-contamination; Brominated-hydrocarbons; Fumes; Controlled-environment; Mortality-rates; Synergism; Fungicides
Final Contract Report
NTIS Accession No.
Mixed Exposures; Work Environment and Workforce
Midwest Research Institute, Biological Sciences Division, Kansas City, Missouri, 100 pages, 29 references
Midwest Research Institute, Biological Sciences Division, Kansas City, Missouri