National Toxicology Program technical report series
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Natl Toxicol Program Tech Rep Ser · May 1993
NTP Toxicology and Carcinogenesis Studies of o-Nitroanisole (CAS No. 91-23-6) in F344 Rats and B6C3F1 Mice (Feed Studies).
o-Nitroanisole is used as an intermediate for the preparation of o-anisidine and in the manufacture of azo dyes. Toxicology and carcinogenesis studies were conducted by administering o-nitroanisole (>99% pure) in the diet to groups of male and female F344 rats and B6C3F1 mice for 14 days, 13 weeks, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Chinese hamster ovary cells, and mouse lymphoma cells. 14-DAY STUDIES: Groups of five male and five female F344 rats received diets containing 0, 583, 1,166, 2,332, 4,665, or 9,330 ppm o-nitroanisole. ⋯ There was some evidence of carcinogenic activity of o-nitroanisole in female B6C3F1 mice based on increased incidences of hepatocellular adenomas. Increased severity of nephropathy in male rats, and increased incidences of focal hyperplasia of the renal tubule epithelium and forestomach ulcers in male rats, and of transitional cell hyperplasia of the urinary bladder, focal hyperplasia of the forestomach, and hyperplasia of transitional epithelium of the kidney pelvis in male and female rats were associated with exposure to o-nitroanisole. Synonyms: Methoxynitrobenzene, nitrophenyl methyl ether
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Natl Toxicol Program Tech Rep Ser · Apr 1993
NTP Toxicology and Carcinogenesis Studies of Pentachloroanisole (CAS No. 1825-21-4) in F344 Rats and B6C3F1 Mice (Feed Studies).
Pentachloroanisole is a chlorinated aromatic compound which is widely distributed at low levels in the environment and in food products. Formation of pentachloroanisole in the environment may result from the degradation of structurally related, commercially important, ubiquitous chlorinated aromatic compounds such as pentachlorophenol and pentachloronitrobenzene which are known rodent toxins or carcinogens. Toxicology and carcinogenesis studies were conducted by administering pentachloroanisole (>99% pure) in corn oil by gavage to groups of male and female F344/N rats and B6C3F1 mice for 16 days, 13 weeks, or 2 years. ⋯ Pentachloroanisole administration was associated with increased incidences of adrenal medulla hyperplasia and hypertrophy and hepatocellular mixed cell foci in male mice. In male and female mice, nonneoplastic liver lesions associated with pentachloroanisole administration included hepatocellular cytologic alteration, Kupffer cell pigmentation, biliary tract hyperplasia, and subacute inflammation. Synonyms: 2,3,4,5,6-pentachloroanisole; methyl pentachlorophenate; methyl pentachlorophenyl ether; o-methylpentachlorophenol; pentachloromethoxybenzene; pentachlorophenyl methyl ether
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Natl Toxicol Program Tech Rep Ser · Feb 1993
Toxicology and Carcinogenesis Studies of Mercuric Chloride (CAS No. 7487-94-7) in F344 Rats and B6C3F1 Mice (Gavage Studies).
Mercuric chloride is an inorganic compound that has been used in agriculture as a fungicide, in medicine as a topical antiseptic and disinfectant, and in chemistry as an intermediate in the production of other mercury compounds. The widespread use of mercury has resulted in increased levels of mercury in rivers and lakes. Mercuric chloride was evaluated in toxicity and carcinogenicity studies because of its extensive use and its occurrence as an environmental pollutant, and because of the lack of adequate long-term rodent studies. ⋯ Increased incidences of nasal mucosa inflammation were associated with mercuric chloride administration in rats. Increased incidences of olfactory epithelial metaplasia in mice were also associated with mercuric chloride administration. Synonyms: Abavit B, calochlor, corrosive sublimate, dichloromercury, mercuric bichloride, mercury chloride, mercury (II) chloride, mercury bichloride, mercury perchloride, sublimate, sulem, bichloride of mercury, corrosive mercury chloride, perchloride of mercury, mercury dichloride Trade name: Fungchex
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Natl Toxicol Program Tech Rep Ser · Jan 1993
Toxicology and Carcinogenesis Studies of Furan (CAS No. 110-00-9) in F344 Rats and B6C3F1 Mice(Gavage Studies).
Furan serves as an intermediate in the synthesis and preparation of numerous linear polymers used to prepare temperature-resistant structural laminates and to prepare copolymers used in machine dishwashing products as alternatives to phosphorus- and nitrogen-containing detergents. Toxicology and carcinogenesis studies were conducted by administering furan (purity > 99%) in corn oil by gavage to groups of F344/N rats and B6C3F1 mice of each sex for 16 days, 13 weeks, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Drosophila melanogaster, mouse bone marrow cells, mouse L5178Y lymphoma cells, and Chinese hamster ovary cells. 16-Day Studies: Groups of five male rats received doses of 0, 5, 10, 20, 40, or 80 mg of furan per kg of body weight and groups of five female rats and five mice of each sex received doses of 0, 10, 20, 40, 80, and 160 mg/kg in corn oil by gavage. ⋯ Nonneoplastic liver lesions associated with furan administration in rats and mice included biliary tract fibrosis, hyperplasia, inflammation, and proliferation, as well as hepatocellular cytomegaly, degeneration, hyperplasia, necrosis, and vacuolization. In rats, increased severity of nephropathy with an associated increased incidence of parathyroid hyperplasia was associated with exposure to furan. Synonyms: Divinylene oxide, tetrole, furfuran, oxole, 1,4-epoxy-1,3-butadiene, axole, oxacyclopentadiene
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Natl Toxicol Program Tech Rep Ser · Mar 1992
NTP Toxicology and Carcinogenesis Studies of Ethylene Thiourea (CAS: 96-45-7) in F344 Rats and B6C3F1 Mice (Feed Studies).
Ethylene thiourea is a white crystalline solid used extensively in the rubber industry as an accelerator in the vulcanization of elastomers. It is also a trace contaminant and metabolic degradation product of a widely used class of ethylene bisdithiocarbamate fungicides. Ethylene thiourea is known to produce thyroid neoplasms in rats and liver neoplasms in mice following long-term administration; thus, it was chosen by the National Toxicology Program in an investigation of the potential value of perinatal exposures in assessing chemical carcinogenicity. ⋯ However, increasing perinatal exposure from 0 to 90 ppm had no effect on incidences of thyroid neoplasms in rats receiving adult exposure to 83 ppm. Increasing perinatal exposure from 0 to 330 ppm was associated with a marginally increased incidence of thyroid neoplasms in female mice receiving adult exposure to 330 ppm, but there were no enhancing effects of perinatal exposure in mice receiving adult exposure to 1,000 ppm. Synonyms: 2-Imidazolidinethione; Imidazoline-2-thiol; 2-mercaptoimidazoline; N,N'-ethylenethiourea; 1,3-ethylenethiourea; 2-imadazoline-2-thiol