Gavage dosing

Gavage dosing of male and female rats with endosulfan (65.3% a-endosulfan, 33.7% P-endosulfan) for 30 days resulted in a greater accumulation of endosulfan in fatty tissue from females than males (Dikshith et al. 1984). The authors speculated that the difference between males and females was a function of more rapid excretion of endosulfan by males than females, and that this could account for the higher sensitivity of female rats to endosulfan toxicity. However, excretion of endosulfan and its metabolites was not directly measured in this study therefore, alternative explanations for the differences in residue content and toxicity caimot be discounted. 

No acute-duration oral MRL was derived for endosulfan because no suitable end point was available among the reliable acute-duration studies. The lowest LOAEL, 1.8 mg/kg/day, was for a serious end point, convulsions in pregnant rabbits, appearing 10 days after the start of daily gavage dosing in the EMC (1981) study. Because animals from both the control and the test groups developed ascites, and six rabbits were added without concurrent controls, the reliability of these results is questionable. 

Marmoset, adult 241 Am in potato powder single gavage dose, 2.0 ng 0.06 Absorption estimate based on comparisons with liver and carcass 241 Am after an intraperitoneal dose Ham et al. 1994... 

Pig, adult Pig, miniature 241 Am citrate aqueous solution, single gavage dose, 190 pig/kg 241 Am citrate aqueous solution, single gavage dose, 75 pig/kg 0.16 0.06 Absorption estimate based on maximum whole-body 241 Am (8 days), without adjustment for excretion Eisele et al. 1987... 

Guinea pig, adult 241 Am nitrate, aqueous solution, single gavage dose, 2-4.4 pig 0.017- -0.031 Absorption estimate based on sum of liver, skeletal and urine 241 Am Sullivan 1980a... 

Rat, adult 241 Am oxide, aqueous suspension, single gavage dose, 33 ig/kg 0.015 ... 

An LD50 of 503 mg/kg was calculated from the results of a study in which adult female mink were administered single doses of diisopropyl methylphosphonate by gavage (doses of 75, 150, 300, 450, 500,... 

In a series of acute lethality studies on U.S. military fluids, single gavage doses (4,250 or 5,000 mg/kg) of one of several polyalphaolefin hydraulic fluids did not produce signs of neurological toxicity in rats within... 

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