Variables: dissolved_organic_carbon Keywords: monitoring Substances: 5-Fluorouracil (GHASVSINZRGABV-UHFFFAOYSA-N) 2-n-Octyl-4-isothiazolin-3-on (OIT) (JPMIIZHYYWMHDT-UHFFFAOYSA-N) 1-(3-Chlorophenyl)-piperazin (VHFVKMTVMIZMIK-UHFFFAOYSA-N)