2-Ethylhexanoic acid was evaluated for acute toxicity in female Fischer F-344 rats (4/dose group) administered single doses of 0, 90, 722, 1445, or 2890 mg/kg of test material by gavage in corn oil. No effects were noted on survival at doses up to 1445 mg/kg, while in the 2890 mg/kg group, 4/4 rats died. The acute LD50 was calculated as 2043 (95% confidence interval = 1445 to 2890) mg/kg. No significant sublethal effects were noted. Two female rats were dermally exposed to test material (dose not reported) under occlusion for 96 hours and observed for dermal irritation. Summary information indicates the epidermal layer was seriously damaged by 24 hours post-exposure, and that regeneration of this tissue occurred during the remainder of the 96-hour observation period. No further information was provided. In a pharmacokinetic study, groups of rats were administered radiolabeled 2-ethylhexanoic acid by oral gavage at doses of 0.1 or 1.0 g/kg. Urine and feces were monotored for 96 hours. Urinary excretion of radioactivity was rapid and was the major route of elimination (about 80% of each dose within 96 hours). Within the 1st 24 hours better than 70% of the high dose and 76% of the low dose were excreted. About 12% of the low dose and 6% of the high dose were excreted in feces. Several metabolites were separated by high performance liquid chromatography, but not identified.