title: Hepatic changes in rats following subchronic administration of FYROL 6, an organophosphorus ester flame retardant.
abstract: This study conducted to evaluate the subchronic toxicity of FYROL 6 [diethyl N,N-bis-(2-hydroxyethyl)aminomethylphosphonate] in rats demonstrated an hepatic effect not commonly reported for related compounds. Sprague-Dawley rats of both sexes were gavaged daily with 0, 10, 100, or 500 mg/kg FYROL 6 in corn oil for 13 wk. No treatment-related mortality and few signs of toxicity were noted during the study. Fyrol 6 did not inhibit plasma, erythrocyte, or brain cholinesterase activities. Treatment-related necropsy and microscopic alterations were restricted to the liver. Increased liver weights, hepatocellular hypertrophy, and eosinophilia of centrilobular hepatocytes were evident in 100-mg/kg females and in both sexes at 500 mg/kg. Morphometric analysis revealed a 40% increase in cross-sectional area of individual hepatocytes in 500-mg/kg males, compared to controls. There was no morphologic evidence of hepatic necrosis or clinical evidence of liver dysfunction. This study demonstrated low toxicity for FYROL 6 and treatment-related changes restricted to the liver suggestive of an adaptive response to FYROL 6.
authors.affiliation: Stauffer Chemical Company, Toxicology Department, Farmington, Connecticut.
authors.forename: A C
authors.initials: AC
authors.lastname: Katz
authors.forename: J C
authors.initials: JC
authors.lastname: Turnier
authors.forename: G M
authors.initials: GM
authors.lastname: Zwicker
authors.forename: G L
authors.initials: GL
authors.lastname: Sprague
mesh_terms: D000818:Animals; D005260:Female; D005411:Flame Retardants / Q000633:toxicity*; D007668:Kidney / Q000187:drug effects / Q000473:pathology; D008099:Liver / Q000187:drug effects / Q000473:pathology*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010755:Organophosphates / Q000633:toxicity*; D009943:Organophosphorus Compounds / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values
chemical_list: D005411:Flame Retardants; D010755:Organophosphates; D009943:Organophosphorus Compounds; C055244:Fyrol 6