Abstract: | The acute ecotoxic effects of ibuprofen and omeprazole and their mixture have been measured using Aliivibrio fischeri as a biomodel. The toxic effects were also tested after 5 days, and an effect-driven approach was used to analyse the results. The toxic effects of the mixtures were compared with the predictions obtained using concentration addition and independent action mathematical methods. According to the Passino and Smith classification, the results indicate that ibuprofen can be considered slightly toxic (10<EC50 <100?mg?L-1), while omeprazole can be denoted as moderately toxic (1<EC50 <10?mg?L-1) to Aliivibrio fischeri. An overestimation of the actual ecotoxic effect of the mixture was found when the concentration addition and independent action methods were applied. Finally, the effect-driven approach indicated that the transformation products of the studied drugs should be prioritized for risk assessment purposes. |