"Desormone Lourd" is a 2,4-Dichlorophenoxyacetic based herbicide that includes 600 g/L 2,4-D. In this study we analyzed the toxic effects of 2,4-D on rat liver. Animals were daily treated with 15, 75 and 150 mg/kg, via oral gavage during 4 weeks. Hepatotoxicity was monitored by quantitative analysis of the serum enzymes markers of hepatotoxicity. Oxidative stress markers, catalase and glutathione reductase (CAT and GR), were analyzed in liver. We also investigated liver tissues histopathologically. Our results revealed that, when rats of 2,4-D treated groups were compared with the control group, the body weight decreased and the liver weight increased significantly at the end of the 4th week. The microscopic evaluation showed that 2,4-D induced hepatic cord disruption, focal necrosis, vessel dilation and pycnotic nucleus. Histological effects were found in all treated groups and their severity was dose dependent. Through sub-acute treatment, starting from the low to the high doses of 2,4-D, it was observed that there were effects on the activity of the serum enzyme markers, on TSP, Alb and the glycemia levels. We also observed a significant reduction in the hepatic antioxidant enzyme activities. To conclude, we can suggest that 2,4-D induces hepatoxicity and cellular alterations in rat. (C) 2010 Elsevier B.V. All rights reserved.