Carcinogenicity of dietary dimethylnitrosomorpholine, N-methyl-N'-nitro-N-nitrosoguanidine, and dibromoethane in rainbow trout.
Eighteen-mo feeding trials of rainbow trout were used to test the carcinogenicity of 5 chemicals in this species. A single exposure level was used for each substance. The doses and chemicals tested were 1,556 ppm 2,6-dimethylnitrosomorpholine (DMNM), 500 ppm N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 2,000 ppm 1,2-dibromoethane (DBE), 2,000 ppm 1,1-dichloroethylene (DCE), and 200 ppm cyclophosphamide (CP). Liver and/or glandular stomach neoplasms were produced by DMNM (liver and stomach), MNNG (stomach), and DBE (chiefly, stomach tumors). In addition, DMNM produced a low incidence of swimbladder papillomas and caused testicular atrophy in 50% of treated males. DCE and CP produced no neoplasms at the exposure levels used. No evidence of other chronic toxicity was seen for any of the 5 compounds.
Hendricks
J D
JD
Marine/Freshwater Biomedical Sciences Center, Oregon State University, Corvallis 97331, USA.
Shelton
D W
DW
Loveland
P M
PM
Pereira
C B
CB
Bailey
G S
GS
D000821:Animal Feed; D000818:Animals; D002273:Carcinogens; D003520:Cyclophosphamide / Q000633:toxicity; D004000:Dichloroethylenes / Q000633:toxicity; D015946:Ethylene Dibromide / Q000633:toxicity*; D005260:Female; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000633:toxicity*; D009602:Nitrosamines / Q000633:toxicity*; D017686:Oncorhynchus mykiss; D012727:Sex Characteristics
D002273:Carcinogens; D004000:Dichloroethylenes; D009602:Nitrosamines; D008769:Methylnitronitrosoguanidine; C014130:N-nitroso-2,6-dimethylmorpholine; D015946:Ethylene Dibromide; C029297:vinylidene chloride; D003520:Cyclophosphamide