Variables: dissolved_organic_carbon concentration electric_conductivity pH Substances: 1-Propanesulfonate (KCXFHTAICRTXLI-UHFFFAOYSA-N) 18-beta-Glycyrrhetinic acid (MPDGHEJMBKOTSU-YKLVYJNSSA-N) 4-5-Dichloro-2-n-octyl-isothiazol-3(2H)-on (DCOIT) (PORQOHRXAJJKGK-UHFFFAOYSA-N)