National Toxicology Program technical report series
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Natl Toxicol Program Tech Rep Ser · Oct 1994
NTP Toxicology and Carcinogenesis Studies of Ozone (CAS No. 10028-15-6) and Ozone/NNK (CAS No. 10028-15-6/ 64091-91-4) in F344/N Rats and B6C3F1 Mice (Inhalation Studies).
There is widespread concern over the health effects of oxidant air pollutants. The state of California and the Health Effects Institute (HEI) (a nonprofit research institute funded jointly by the U. S. ⋯ There was no evidence that exposure to 0.5 ppm ozone enhanced the incidence of NNK-induced pulmonary neoplasms in male rats. Exposure of male and female rats to ozone for 2 years or 125 weeks was associated with goblet cell hyperplasia and squamous metaplasia in the nose, squamous metaplasia in the larynx, and metaplasia (extension of bronchial epithelium into the centriacinar alveolar ducts) and interstitial fibrosis in the lung. Exposure of male and female mice to ozone for 2 years or 130 weeks was associated with hyperplasia and squamous metaplasia in the nose and inflammation (histiocytic infiltration) and metaplasia (extension of bronchial epithelium into the centriacinar alveolar ducts) of the lung.
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Natl Toxicol Program Tech Rep Ser · Jan 1994
NTP Toxicology and Carcinogenesis Studies of o-Benzyl-p-Chlorophenol (CAS No. 120-32-1) in F344/N Rats and B6C3F1 Mice (Gavage Studies).
o-Benzyl-p-chlorophenol is an aryl halide biocide with widespread use in hospitals and households as a broad-spectrum germicide in disinfectant solutions and soap formulations for general cleaning and disinfecting. Human exposure to o-benzyl-p-chlorophenol occurs by absorption through the skin and mucous membranes and by ingestion. Toxicity and carcinogenicity studies were conducted by administering o-benzyl-p-chlorophenol (approximately 97% pure) in corn oil by gavage to male and female F344/N rats and B6C3F1 mice for 16-days, 13-weeks, and 2-years. ⋯ Other lesions considered to be associated with the nephropathy and the secondary hyperparathyroidism in male rats and in male and female mice included fibrous osteodystrophy and soft tissue mineralization. Increased incidences of squamous cell hyperplasia of the forestomach were observed in mice. Synonyms: 2-benzyl-4-chlorophenol, 4-chloro-2-benzylphenol, 4-chloro-2-(phenylmethyl)phenol, 4-chloro-alpha-phenol o-cresol, p-chloro-o-benzylphenol, 2-hydroxy-5-chlorodiphenylmethane Trade names: Bio-Clave, Chlorophene, Clorofene, Clorophene, Ketolin H, Nipacide BCPR, Preventol BPR, Santophen 1, Septiphene
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Natl Toxicol Program Tech Rep Ser · Aug 1993
NTP Toxicology and Carcinogenesis Studies of Oxazepam (CAS No. 604-75-1) in Swiss-Webster and B6C3F1 Mice (Feed Studies).
Oxazepam is one of a number of benzodiazepines used therapeutically as a sedative-hypnotic and antianxiety agent. Toxicology and carcinogenesis studies were performed by administering oxazepam (greater than 99% pure) in feed to male and female Swiss-Webster and B6C3F1 mice for 14 weeks, 57 weeks (Swiss-Webster), or 2 years (B6C3F1). Neurobehavioral assessments were performed during the studies. ⋯ Administration of oxazepam to Swiss-Webster mice resulted in centrilobular hepatocellular hypertrophy and increased incidences and severity of systemic amyloidosis. Administration of oxazepam to B6C3F1 mice also resulted in centrilobular hepatocellular hypertrophy. Synonyms: 7-Chloro-1,3-dihydro-3-hydroxy-5-phenyl-2 H - 1,4-benzodiazepin-2-one Trade Names: Tazepam, Wy-3498, Serax
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Natl Toxicol Program Tech Rep Ser · Apr 1997
NTP Toxicology and Carcinogenesis Studies of Tetrafluoroethylene (CAS No. 116-14-3) in F344 Rats and B6C3F1 Mice (Inhalation Studies).
Tetrafluoroethylene is used in the production of polytetrafluoroethylene (Teflon(R)) and other polymers. Tetrafluoroethylene was nominated by the National Cancer Institute for toxicity and carcinogenicity studies based on the potential for human exposure to the chemical due to the large production volume and on the lack of adequate data for tetrafluoroethylene in the literature. Male and female F344/N rats and B6C3F1 mice were exposed to tetrafluoroethylene (98% to 99% pure) by whole body inhalation exposure for 16 days, 13 weeks, or 2 years. ⋯ Exposure of rats to tetrafluoroethylene resulted in increased incidences of renal tubule hyperplasia and degeneration in males and females, increased severity of kidney nephropathy in males, and increased incidences of liver angiectasis and cataracts in females. Exposure of mice to tetrafluoroethylene resulted in increased incidences of hematopoietic cell proliferation of the liver in females, liver angiectasis in males and females, renal tubule dilatation in males, renal tubule karyomegaly in males and females, and splenic hematopoietic cell proliferation in males and females. Synonyms: Perfluoroethylene; tetrafluoroethene; 1,1,2,2-tetrafluoroethylene; TFE
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Natl Toxicol Program Tech Rep Ser · Aug 1996
NTP Toxicology and Carcinogenesis Studies of 1-Amino-2,4-Dibromoanthraquinone (CAS No. 81-49-2) in F344/N Rats and B6C3F1 Mice (Feed Studies).
1-Amino-2,4-dibromoanthraquinone is an anthraquinone-derived vat dye, a member of a class of insoluble dyes that are impregnated into textile fibers. Five anthraquinone-derived dyes with representative and diverse structures, as well as the parent chemical, anthraquinone, were selected for NTP Toxicology and Carcinogenesis evaluation. Similar to the benzidine dye initiative, the rationale for selecting these vat dyes was to generate sufficient toxicologic data to permit more reliable predictions of carcinogenicity to be made on other chemicals in this class, thereby eliminating or reducing the need to study every anthraquinone dye. 1-Amino-2,4-dibromoanthraquinone is the last anthraquinone-derived dye in this group to be studied. ⋯ Exposure of male and female rats to 1-amino-2,4-dibromoanthraquinone for 2 years was associated with basophilic focus (males only), clear cell focus, eosinophilic focus, and pigmentation in the liver; renal tubule hyperplasia, renal tubule pigmentation, and transitional cell hyperplasia in the kidney; transitional cell hyperplasia, squamous metaplasia, and stromal metaplasia (females only) in the urinary bladder; squamous hyperplasia, hyperkeratosis, ulceration, and inflammation of the forestomach mucosa; and seminal vesicle atrophy. Exposure of male and female mice to 1-amino-2,4-dibromoanthraquinone for 2 years was associated with centrilobular hepatocellular hypertrophy (males only), basophilic focus, clear cell focus (females only), eosinophilic focus, and pigmentation in the liver; pigmentation in the kidney; and hyperplasia, basal cell hyperplasia, hyperkeratosis, and inflammation of the forestomach mucosa. Synonym: ADBAQ