Toxicity studies of methamidophos on the physiological aspects of mammalian organs are limited in the literature. This study aimed to assess hepatic and renal functions in response to a sublethal dose of methamidophos in male domestic rabbits. A daily dose of 1/10 LD50 metha- midophos was given orally to rabbits for 6 weeks. Control animals were given distilled water. Blood samples were collected and analyzed weekly. Serum glucose and bilirubin were increased upon methamidophos intake versus control, with the significant change commenced from the second and fifth weeks, respectively. In general, alanine aminotransferase, aspartate aminotransferase, g-glutamyl transferase, and alkaline phosphatase showed significant elevation throughout the whole experiment. Conversely, cholinesterase was significantly inhibited all over the experimental intervals studied. Serum urea and creatinine showed a significant increase whereas total protein, albumin, and globulin exhibited a significant decrease during the last five weeks of the experiment. Hypocalcemia and hyperphosphatemia were also observed in methamidophos- treated rabbits. Methamidophos exposure at a sublethal dose had a potential toxic effect on liver and kidney functions as indicated by significant alterations in their biomarkers. Such findings can then be extrapolated to human beings to assess the potential hazards in human populations due to methamidophos exposure.
