600276 Disclosed is a process for reducing and/or maintaining the total viable count of bacteria in an aqueous mineral preparation comprising a steps of: (a) adding at least one aldehyde-containing and/or aldehyde-releasing and/or phenolic and/or isothiazoline biocide to said aqueous mineral preparation (such as formaldehyde, glutaraldehyde, benzyl alcoholmono(poly)-hemiformal, ethyleneglycolhemiformal (EGHF), [1,2-ethanediylbis(oxy)]-bis-methanol, tetrahydro-1,3,4,6-tetrakis(hydroxylmethyl)imidazo[4,5-d]imidazole-2,5(1H,3H)-dione (TetraMethylolAcetyleneDiurea / TMAD), orthophenylphenol (OPP), 2-methyl-4-isothiazoline-3-one (MIT), 5-chloro-2-methyl-2H-isothiazolin-3-one (CIT) or 1,2-benzisothiazoline-3-one (BIT)) in an amount corresponding to from 90 to 1350 ppm based on the weight of the aqueous phase of said aqueous preparation wherein: said mineral comprises at least one of: a ground natural calcium carbonate, a precipitated calcium carbonate, a dolomite, a surface-modified calcium carbonate, or a mixture thereof and step (b), which may be simultaneous and/or distinct relative to step (a), of adding at least one monoalcohol primary alkanol amine selected from 2-amino-2-methyl-1-propanol, 2-aminoethanol and mixtures thereof, in an amount corresponding to from 600 to 1200 ppm based on the weight of the aqueous phase of said aqueous preparation. Also disclosed is an aqueous preparation obtained by the above process. Further disclosed is the use of a monoalcohol primary alkanol amine selected from 2-amino-2-methyl-1-propanol, 2-aminoethanol and mixtures thereof as a biocidal activity enhancing compound in an aqueous ground natural calcium carbonate and/or precipitated calcium carbonate and/or dolomite and/or surface-reacted calcium carbonate-comprising mineral preparation comprising at least one aldehyde containing and/or aldehyde-releasing and/or phenolic and/or isothiazoline biocide, where the total amount of said biocide(s) in the aqueous preparation is from 90 pp
