title: Dioxin intoxication from chronic exposure of horses to pentachlorophenol-contaminated wood shavings.
abstract: Investigations into the cause of health problems on a horse-breeding farm led to the discovery of high concentrations (630 to 9,810 mg/kg of bedding) of pentachlorophenol in wood shavings used as bedding for horses over a period of 2 to 4 years. Toxicologic signs in the horses were characteristic of toxic effects associated with exposure of polychlorinated dibenzo-p-dioxins and dibenzofurans. Tissue residue analysis confirmed presence of toxic polychlorinated dibenzo-p-dioxin and dibenzofuran isomers known to be in pentachlorophenol, substantiating the bioavailability of polychlorinated dibenzo-p-dioxins and dibenzofurans in the wood shavings. The findings provide evidence that residue concentrations in the range of 2 ng/g of toxic polychlorinated dibenzo-p-dioxin isomers in liver or fat correlate with toxicologic effects in horses.
authors.affiliation: College of Veterinary Medicine, Environmental Health Sciences Center, Oregon State University, Corvallis 97331.
authors.forename: N I
authors.initials: NI
authors.lastname: Kerkvliet
authors.forename: S L
authors.initials: SL
authors.lastname: Wagner
authors.forename: W B
authors.initials: WB
authors.lastname: Schmotzer
authors.forename: M
authors.initials: M
authors.lastname: Hackett
authors.forename: W K
authors.initials: WK
authors.lastname: Schrader
authors.forename: B
authors.initials: B
authors.lastname: Hultgren
mesh_terms: D000818:Animals; D003872:Dermatitis / Q000209:etiology / Q000662:veterinary*; D005260:Female; D006734:Horse Diseases / Q000139:chemically induced*; D006736:Horses; D008099:Liver / Q000473:pathology; D007752:Obstetric Labor, Premature / Q000139:chemically induced / Q000662:veterinary; D010416:Pentachlorophenol / Q000506:poisoning*; D011041:Poisoning / Q000209:etiology / Q000662:veterinary; D011247:Pregnancy; D011248:Pregnancy Complications / Q000139:chemically induced / Q000662:veterinary*; D014934:Wood
chemical_list: D010416:Pentachlorophenol