A method for reducing antimicrobial compound levels in a liquid composition containing at least one antimicrobial compound. The method comprises contacting said liquid composition with a functionalized resin. Antimicrobial compounds that may be removed by this method include isothiazolin-3-ones, e.g., 2-methyl-4-isothiazolin-3-one； 5-chloro-2-methyl-4-isothiazolin-3-one； 2-n-octyl-4-isothiazolin-3-one； 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one； 1,2-benzisothiazolin-3-one and N-alkyl derivatives thereof, especially N-methyl and N-n-butyl； 2, 2-dibromo-3-nitrilopropionamide (DBNPA)； 2-bromo-2-nitropropanediol (BNPD)； dithio-2,2'-bis(benzmethylamide) (DTBMA)； hexetidine； chlorphenesin, C 1 -C 4 alkyl-4-hydroxybenzoates (alkyl parabens)； 3-iodopropynylbutylcarbamate (IPBC)； formaldehyde releasers and mixtures thereof.
