The acute effects of oral administration of a single dose of T-2 toxin (2.0 mg/kg body wt) to rats on whole liver lipid metabolism were studied at 8, 16 and 24 h post-treatment. Administration of T-2 toxin significantly increased liver and microsomal total lipids, free cholesterol, esterified cholesterol and triglycerides initially at 8 h, which subsequently returned to control values at 24 h. However, no significant alterations were observed in the contents of whole liver and liver microsomal total phospholipids and phosphatidyl choline, except that phosphatidyl ethanolamine and sphingomyelin + lysophosphatidyl ethanolamine contents in liver at 16 and 24 h and sphingomyelin + lysophosphatidyl ethanolamine content in liver microsomes at all three periods were significantly lower. The incorporation of 1-14C-acetate into whole liver and liver microsomal total lipids was reduced at 16 and 24 h post feeding. However, the incorporation of 1-14C-acetate into liver and microsomal free cholesterol, esterified cholesterol and triglycerides was significantly higher at 8 h, subsequently returning to the control value at 24 h; incorporation was significantly lower even into microsomal triglycerides. The incorporation of 1-14C-acetate into liver and its microsomal total phospholipids, phosphatidyl choline, phosphatidyl ethanolamine and sphingomyelin + lysophosphatidyl ethanolamine, was significantly decreased at all three periods post toxin treatment. The results suggested that T-2 toxin inhibited the incorporation of 14C-acetate mainly into liver and its microsomal phospholipids and their subfractions in rats.