National Toxicology Program technical report series
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Natl Toxicol Program Tech Rep Ser · Sep 2000
NTP Toxicology and Carcinogenesis Studies of Primidone (CAS No. 125-33-7) in F344/N Rats and B6C3F1 Mice (Feed Studies).
Primidone is used alone or with other anticonvulsants in the control of grand mal, psychomotor, and focal epileptic seizures. It may control grand mal seizures refractory to other anticonvulsant therapy. Primidone was nominated by the National Cancer Institute for 2-year toxicology and carcinogenicity studies due to its human use as an anticonvulsant. ⋯ Exposure of male mice to primidone resulted in hepatocyte centrilobular hypertrophy and thyroid gland follicular cell hyperplasia. Exposure of female mice to primidone resulted in hepatocyte centrilobular hypertrophy and cytoplasmic vacuolization, eosinophilic focus, and thyroid gland follicular cell hyperplasia. Synonyms: 5-Aethyl-5-phenyl-hexahydropyrimidin-4,6-dion; 2-deoxyphenobarbital; 2-desoxyphenobarbital; desoxyphenobarbitone; 5-ethyldihydro-5-phenyl-4,6 (1H,5H)-pyrimidinedione; 5-ethylhexahydro-4,6-dioxo-5-phenylphrimidine; 5-ethylhexahydro-5-phenylpyrimidine-4,6-dione; 5-ethyl-5-phenylhexahydropyrimidine-4,6-dione Trade names: Cyral; Hexadiona; Hexamidine; Lepimidin; Lepsiral; Majsolin; Midone; Milepsin; Misodine; Misolyne; Mizodin; Mizolin; Mylepsin; Mylepsinum; Mysedon; Mysoline; Prilepsin; Primacione; Primaclone; Primacone; Primakton; Primadon; Prysoline; Pyrimidone; ROE 101; Sertan
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Natl Toxicol Program Tech Rep Ser · Sep 2000
NTP Toxicology and Carcinogenesis Studies of Gallium Arsenide (CAS No. 1303-00-0) in F344/N Rats and B6C3F1 Mice (Inhalation Studies).
Gallium arsenide is used primarily to make light- emitting diodes, lasers, laser windows, and photodetectors and in the photoelectronic transmission of data through optical fibers. Gallium arsenide was nominated for study because of its widespread use in the microelectronics industry, the potential for worker exposure, and the absence of chronic toxicity data. Male and female F344/N rats and B6C3F1 mice were exposed to gallium arsenide particles (greater than 98% pure; mass median aerodynamic diameter = 0.8 to 1.0 &mgr;m) by inhalation for 16 days, 14 weeks, or 2 years. ⋯ There was no evidence of carcinogenic activity in male or female B6C3F1 mice exposed to 0.1, 0.5, or 1.0 mg/m(3). Exposure to gallium arsenide caused a spectrum of nonneoplastic lesions in the lung of rats and mice, the larynx of male rats and hyperplasia of the tracheobronchial lymph node in mice. Synonym: Gallium monoarsenide.
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Natl Toxicol Program Tech Rep Ser · Nov 1999
NTP Toxicology and Carcinogenesis Studies of Triethanolamine (CAS No. 102-71-6) in F344 Rats and B6C3F1 Mice (Dermal Studies).
Triethanolamine is widely used as an ingredient in emulsifiers, thickeners, wetting agents, detergents, and alkalinizing agents in cosmetic products; as a chemical intermediate for anionic and nonionic surfactants and surface active agents in household cleaning agents, textiles, herbicides, pharmaceutical ointments, and other products; as a vulcanization accelerator in the manufacture of rubber; and in many other industrial applications. The National Cancer Institute nominated triethanolamine for study because of its widespread use in cosmetics and other consumer products, its high potential for worker exposure due to its many industrial uses, and its potential for conversion to the carcinogen N -nitrosodiethanolamine. Dermal application was chosen as the route of exposure to mimic the principal means of human exposure to triethanolamine and because considerable systemic exposure is achieved with this route. ⋯ The study in male and female B6C3F1 mice was considered inadequate, because the presence of a Helicobacter hepaticus infection complicated inter pretation of the relationship between triethanolamine administration and liver neoplasms in these animals. Dosed rats and mice had varying degrees of acanthosis and inflammation, dosed rats had ulceration, and dosed female rats had epidermal erosion at the site of skin application. Synonyms: Nitrilo-2,2',2"-triethanol; 2,2',2"-nitrilotriethanol; 2,2',2"-nitrilotrisethanol; TEA; triaethanolamin-NG; triethanolamin; triethylolamine; tri(hydroxyethyl)amine; 2,2',2"-trihydroxytriethylamine; trihydroxytriethylamine; tris(hydroxyethyl)amine; tris(2-hydroxyethyl)amine; triethylolamine; trolamine Trade Names: Daltogen; Sterolamide; Thiofaco T-35
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Natl Toxicol Program Tech Rep Ser · Feb 1999
NTP Toxicology and Carcinogenesis Studies of Isobutyraldehyde (CAS No. 78-84-2) in F344/N Rats and B6C3F1 Mice (Inhalation Studies).
Isobutyraldehyde, a branched alkyl aldehyde, is used as a chemical intermediate and flavoring agent. It was nominated by the National Cancer Institute for toxicity and carcinogenicity studies by the NTP. Reasons for nomination and selection of isobutyraldehyde for study included its high potential for human exposure as suggested by its high production volume, its use as a chemical intermediate and food flavoring agent, suspicion of carcinogenicity due to an increased incidence of cancer at an aldehyde manufacturing plant where workers were exposed to a variety of aldehydes, its structural relationship to formaldehyde (a nasal carcinogen in rats), and the lack of toxicity and carcinogenicity studies on isobutyraldehyde in animals. ⋯ In male and female rats, exposure to isobutyraldehyde induced squamous metaplasia and suppurative inflammation of the nasal respiratory epithelium and degeneration of the nasal olfactory epithelium. In male and female mice, exposure to isobutyraldehyde caused degeneration of the nasal olfactory epithelium. Synonyms: Dimethylacetaldehyde; 2-formylpropane; isobutanal; isobutylcarboxaldehyde; isobutyral; isobutyric aldehyde; isobutyrylaldehyde; isopropylformaldehyde; 2-methylpropanal; 2-methyl-1-propanal; a-methylpropionaldehyde; 2-methylpropionaldehyde; valine aldehyde
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Natl Toxicol Program Tech Rep Ser · Sep 1998
NTP Toxicology and Carcinogenesis Studies of Chloroprene (CAS No. 126-99-8) in F344/N Rats and B6C3F1 Mice (Inhalation Studies).
Chloroprene is used almost exclusively in the manufacture of neoprene (polychloroprene). Chloroprene was chosen for study because it is a high-volume production chemical with limited information on its carcinogenic potential and because it is the 2-chloro analogue of 1,3-butadiene, a potent, multi-species, multi-organ carcinogen. Male and female F344/N rats and B6C3F1 mice were exposed to chloroprene (greater than 96% pure) by inhalation for 16 days, 13 weeks, or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Drosophila melanogaster, and B6C3F1 mice (bone marrow cells and peripheral blood erythrocytes).