title: Hexachlorobenzene toxicity in the monkey primordial germ cell without induced porphyria.
abstract: Hexachlorobenzene is a persistent chlorinated organic chemical that has been detected in many tissues from a variety of species including human ovary and human ovarian follicular fluid. When administered in high dosage to nonhuman primates, hexachlorobenzene causes destruction of ovarian primordial germ cells in association with systemic toxicity. The purpose of these experiments was to assess relative ovarian germ cell sensitivity at much lower dosages of hexachlorobenzene that do not produce systemic effects and additionally to evaluate oocyte function by means of the response to superovulation, fertilization, and embryo cleavage during a cycle of in vitro fertilization in the cynomolgus monkey. Hexachlorobenzene in dosages of 0.1, 1.0, and 10.0 mg/kg/day was administered orally by gelatin capsule for 90 days. There was a dose-dependent accumulation of HCB in serum and other tissues without any change in the serum estradiol response to human menopausal gonadotropin, oocyte recovery, oocyte maturation, oocyte fertilization in vitro, and early embryo cleavage rate. There was a dose-related toxic effect observed in primordial germ cells at the lowest dose despite no evidence of systemic or hepatic effects. As there were no changes in the urinary porphyrin excretion, the mechanism of hexachlorobenzene ovotoxicity may be distinct from hexachlorobenzene-induced cytochrome P-450-dependent inhibition of uroporphobilinogen decarboxylase in the liver, although such intraovarian metabolism cannot be excluded.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Calgary/Foothills Hospital, Alberta, Canada.
authors.forename: J F
authors.initials: JF
authors.lastname: Jarrell
authors.forename: A
authors.initials: A
authors.lastname: McMahon
authors.forename: D
authors.initials: D
authors.lastname: Villeneuve
authors.forename: C
authors.initials: C
authors.lastname: Franklin
authors.forename: A
authors.initials: A
authors.lastname: Singh
authors.forename: V E
authors.initials: VE
authors.lastname: Valli
authors.forename: S
authors.initials: S
authors.lastname: Bartlett
mesh_terms: D000818:Animals; D005260:Female; D005307:Fertilization in Vitro; D005854:Germ Cells / Q000187:drug effects*; D006581:Hexachlorobenzene / Q000493:pharmacokinetics / Q000633:toxicity*; D008099:Liver / Q000503:physiopathology; D008111:Liver Function Tests; D008252:Macaca fascicularis; D009865:Oocytes / Q000187:drug effects; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects; D011164:Porphyrias / Q000139:chemically induced* / Q000473:pathology; D011166:Porphyrins / Q000652:urine; D011247:Pregnancy; D014018:Tissue Distribution
chemical_list: D011166:Porphyrins; D006581:Hexachlorobenzene