Abstract: A description is given of a filter cigarette, whose filtera) contains fibrous filter material,b) contains an additive with an antimutagenic action on the cigarette smoke in a quantity of less than 15 wt. %, based on the fiber weight of the filter andc) on smoking a similar unventilated filter cigarette, but not containing additive, has a nicotine retention R.sub.N (in %) (determined according to CORESTA recommended method No. 9) satisfying the following formula:R.sub.N .gtoreq.100*(1-D)in which:D=exp(A*B+C),withA=21 mm-filter length (mm) for filter lengths.ltoreq.25 mm orA=-4 mm for filter lengths>25 mm,B=9.3*10.sup.-3 (1/mm) andC=-(d.sup.4 *.DELTA.p*K+L)with d=filter diameter (mm),.DELTA.p=draw resistance of filter (mm hydraulic pressure),K=1.0228*10.sup.-6 (1/(mm.sup.4 *mm hydraulic pressure)) andL=0.2334.

Abstract: Structures are formed from cellulose acetate in which an additive is present or on this surface the additive consisting of a nitrogenous organic compound which by degradation by microorganisms forms basic decomposition products, in particular ammonia, and/or--basic--compounds having an NH group or NH groups and/or an NH.sub.2 group or NH.sub.2 groups. The structures may have the form of filaments, staple fibers, films, foils, sheets or other objects. The structures in the form of filaments and/or staple fibers are used for the manufacture of filter tows. The filter tow of this kind is described. The filter tow is for the manufacture of a tobacco smoke filter element, and such a tobacco smoke filter element is described.

Abstract: A filter tow from cellulose acetate filaments and/or staple fibers is described on the surface of which an additive from cellulose chain-splitting enzymes is present, at least the surface of the filaments and staple fibers consisting of a cellulose acetate having an acetyl number of less than 53%, preferably less than 49%. The method for the production of such a filter tow comprises spinning cellulose acetate filaments from a solution in acetone, of cellulose acetate of an acetyl number of at least 53% if necessary, cutting the filaments to staple fibers, gathering the filaments and/or staple fibers to a filter tow and applying an additive, the filaments and staple fibers being hydrolyzed and as additive one of cellulose chain-splitting enzymes is used. There are described also a tobacco smoke filter element from such a filter tow and a method for its production.

Abstract: A filter tow of cellulose acetate filaments and/or cellulose acetate staple fibers, has at least the surface of the filaments and staple fibers consisting of a cellulose acetate having an acetyl number of less than 53%, preferably less than 49%. The method for the manufacture of the filter tow comprises the spinning of cellulose acetate filaments from a solution of cellulose acetate having an acetyl number of at least 53% in acetone, if necessary, cutting the filaments into staple fibers, and combining the filaments and/or staple fibers to a filter tow, the filaments or staple fibers being hydrolyzed so that at least the cellulose acetate at the surface of the filaments and staple fibers has an acetyl number of less than 53%, preferably less than 49%. The invention involves also a tobacco smoke filter element made from the filter tow, as well as a method for the manufacture of the tobacco smoke filter element.