PARENT SESSION
PS1 - Wildlife Toxicology
Sunday, 17 November 2002
8:00 AM to 6:30 PM
Exhibit Hall

(P042) PCB 126 induces mandibular and maxillary pseudocarcinomatous hyperplasia and reproductive dysfunction in mink (Mustela vison).

Beckett, Kerrie^*,1, Yamini, Behzad¹, Aulerich, Richard¹, Bursian, Steven¹, ¹ Michigan State University, East Lansing, MI, USA

ABSTRACT- Previous studies from our laboratory have indicated that young mink fed 24.0 g 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126)/kg diet or 2.4 g 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)/kg diet developed a mandible and maxillary lesion that consisted of proliferation of squamous epithelium in the periodontal ligament, osteolysis of adjacent alveolar bone, and loose and displaced teeth. Additionally, adult female mink fed 5.0 g TCDD/kg diet exhibited only histologically relevant indications of this lesion. The current study was designed to determine if lower concentrations of PCB 126 would induce the lesion when fed to female mink four weeks prior to breeding continuing through lactation and maturation of the developing kits. Standard dark female mink were fed diets containing 0, 0.24, 2.4, or 24.0 g/kg diet of PCB 126. At weaning, the surviving kits were maintained on their respective diet. Females fed 0.24 g PCB 126/kg diet whelped normal litters, and no impaired implantation or fetal death was noted. Females fed 2.4 and 24.0 g PCB 126/kg diet with confirmed matings failed to whelp, but upon necropsy the uteri showed fetal implantation sites. Those females were kept on their respective diets to assess development of the jaw lesion. Female mink on 24.0 g PCB 126/kg diet had clinical signs of the jaw lesion after approximately ten weeks of exposure. Females fed 2.4 g PCB 126/kg diet also exhibited clinical signs of the jaw lesion after approximately 36 weeks of exposure. Characteristically, the lesion is identified as an initial increase in plaque accrual and increased tissue destruction, with eventual resorption of the alveolar bone and loss of fibrous attachments to the teeth root-surface. Apical migration of the junctional epithelium ensues. These are classical conditions of periodontitis, but no inflammation was observed upon histopathologic examination. In addition, significant changes were observed in both serum chemistries and hematologic parameters.

Key words: mink, pcb 126, jaw lesion, reproductive dysfunction