The objective of this study was to identify a possible effect of food on the accelerationof decontamination in blue mussels, Mytilus edulis, containing diarrhetictoxins belonging to the okadaic acid (OA) structural group. An experimental protocol wasdesigned to describe and compare the decontamination kinetics and detoxification rates ofnaturally OA-contaminated mussels that had either received or not received food for threeweeks. The protocol was applied in two trials (in June 2006 and June 2007, called Ker06and Ker07), conducted one year apart on samples of mussels collected in the same area, atthe same season. Okadaic acid (OA), the main lipophilic toxin produced by the toxic algaDinophysis acuminata, was analysed over the course of thedecontamination, in hydrolysed (total OA) and non hydrolysed (free OA) digestive glandextracts, in order to estimate acyl-esters (7-O-acyl-ester derivatives ofOA) concentrations. OA analyses were also made for toxin presence in biodeposits and inthe aqueous phase. Bivalve physiological status was evaluated by biomass measurements (dryweight of flesh) and two biochemical compounds (total lipid and glycogen concentrations).Measured physiological parameters showed that mussels did not suffer under experimentalconditions. Both trials showed that the food accelerated the elimination of free and totalOA. This effect cannot be attributed to a dilution of the toxin in the tissue, as resultsexpressed in toxin burden led to the same conclusion. The kinetic models ofdecontamination differed between the two experiments: the model was linear for Ker06,provided that the values corresponding to the first two days were discarded, whereas datafitted a decreasing exponential curve better in Ker07. Detoxification rates increased asthe food supply increased. After three weeks of experimentation, the detoxification ratesfor total OA in Ker06 and Ker07 were 52 and 61%, respectively, in unfed mussels and 90 and89% in fed mussels (with the highest level in Ker07). Comparisons between the free OA andesters showed that detoxification rate was higher for free OA than for esters, whateverthe level of food supply. The results of this study suggest that food increase probablyaccelerates elimination of OA and OA-esters but the latter are eliminated at a lowerspeed.