Humans are exposed to the hepatotoxic aflatoxin B1 (AFB1) and nephrotoxic ochratoxin A (OTA) through diet. However, kinetic and toxicological data after their co-administration are scarce. In this study, a single oral dose of AFB1 (0.25 mg/kg bw) + OTA (0.5 mg/kg bw) was administered to fasted F344 rats. Blood, liver and kidney were harvested at different timepoints for mycotoxins quantification, relative weight calculation, clinical biochemistry and histopathology analysis. Toxicity parameters pointed to acute toxicity in liver due to AFB1. No remarkable toxicity was observed in kidneys or immunological organs. Maximum observed concentrations in plasma (C-max) were at 10 min and 2 h for AFB1 and OTA, respectively. AFB1 plasma concentration could indicate a rapid absorption/metabolism of the mycotoxin; and AFB1 liver and kidney concentrations were lower than LOQ and LOD, respectively. For OTA, C-max was 4326.2 mu g/L in plasma. In kidney and liver C-max was reached at 8 h and concentrations were very similar between both organs at all timepoints. Due to the low levels of AFB1, the effect of OTA on AFB1 kinetics could not be assessed. However, AFB1 seems not to affect OTA kinetics, as its profile seems very similar to kinetic studies performed only with OTA in similar conditions. (C) 2012 Elsevier Ltd. All rights reserved.