Abstract Peroxyacids RCOOOH (R= n C 7 H 15 to n C 13 H 27) are very good decontamination reagents. Paraoxon (O, O-diethyl Op nitrophenyl phosphate, VX [O-ethyl S (2-diisopropylaminoethyl) methylphos-phorothiolate] and HD (2, 2′-dichlorodiethylsulfide) react for example, with perdodecanoïc acid, completely in a few seconds. The reaction rate is enhanced by micellar catalysis.