Non-steroidal anti-inflammatory drugs diclofenac and naproxen are widely used for the treatment of arthritis, ankylosing spondylitis, and acute muscle pain. However, most of them are usually not metabolized and simply pass through human body. These drugs are difficult to be decomposed by general waste treatment strategies and have caused serious environmental concerns. We report a rapid and efficient conversion of diclofenac and naproxen by chloroperoxidase-catalyzed H2O2-oxidation, a heme protein isolated from Caldarimyces fumago. Complete conversion of diclofenac and naproxen was achieved in only 9 and 7 min respectively with 0.1 mmol L-1 H2O2 and nanomolar enzyme concentration at pH 3.0. The converted products were identified by HPLC-MS and NMR, suggesting involvement of multiple steps in CPO catalyzed conversion. Our work demonstrated that CPO treatment (with COD removal of 4.9%, 9.1% for diclofenac and naproxen, respectively) followed by existing bioremediation technologies (activated sludge) greatly improved the decontaminating these two drugs from waste water (COD removal was enhanced to 85% and 86%, respectively). The eco-toxicity evaluation according to the 72-h EC50 value using the green algae Chlorella Pyrenoidos as ecological indicators showed that the converted products of diclofenac and naproxen had lower toxicity than the original drugs. (C) 2017 Elsevier B.V. All rights reserved.