Paternal effects from methamidophos administration in mice.
Burruel-RV; Raabe-GO; Overstreet-WJ; Wilson-WB; Wiley-ML
Toxicol Appl Pharmacol 2000 Jun; 165(2):148-157
In this study, the mouse was used to evaluate paternal germline exposure to the organophosphate methamidophos for its potential to produce adverse effects on spermatozoa and in the offspring. There have been reports that organophosphate exposure can increase abnormal sperm morphology in mice. However, effects transmitted to the offspring following paternal exposure have not been reported previously. The maximum tolerated dose (MTD) was 7.5 mg kg21 body weight and this dose resulted in no deaths, although blood plasma cholinesterase activity was still decreased. Males were euthanized 4 weeks after an acute intraperitoneal injection of methamidophos (0.5, 3.75, 5.0, and 7.5 mg kg21 body wt) and the number of spermatids per gram testes and sperm morphology were analyzed. In this study, abnormal sperm morphology on a per group basis exhibited a dose-response significantly related to increased methamidophos exposure as indicated by regression analysis and a nested ANOVA (p < 0.0001). Preimplantation embryos that were conceived 6 weeks after paternal methamidophos exposure (5 mg kg21 body wt) exhibited a significant increase in cleavage arrest. Fertility of males was also affected as shown by a decrease in the number of two- to four-cell embryos per male (postexposure week 6) and an increase in the number of degenerated embryos (postexposure weeks 4-6). We conclude that methamidophos may have the potential to produce transmissible adverse embryonic effects following an acute paternal germline exposure.
Exposure-assessment; Exposure-levels; Exposure-limits; Chemical-properties; Chemical-extraction; Spermatozoa; Animal-studies; Blood-sampling; Blood-serum; Blood-tests; Reproductive-effects; Reproductive-hazards; Dose-response; Fertility; Germ-cells; Germicides; Pesticides; Pesticides-and-agricultural-chemicals; Insecticides; Organo-phosphorus-pesticides
Victoria R. Burruel, Institute of Toxicology and Environmental Health, University of California, Old Davis Road, One Shield Ave, Davis, CA 95616-8615
Toxicology and Applied Pharmacology
University of California - Davis