Abstract: A porous open-cell reactive filled material containing a polymeric matrix and a reactive filler. According to the invention, use is made as the polymeric matrix of foamed polyvinylformal and foamed polyurethane. As the reactive filler use is made of finely divided ion-exchange fibres, complex-forming fibres or mixtures thereof in an amount of from 10 to 80% by mass of the final material. Use is made of ion-exchange fibres on the basis of polyvinylalcohol, polyacrylic, cellulose-regenerated, phenolaldehyde, polyolefine, polyvinylhalide fibres. As the complex-forming fibres use is made of fibres based on polyacrylic, polyvinylalcohol, cellulose-regenerated fibres.