Variables: dissolved_organic_carbon Substances: MCPA (WHKUVVPPKQRRBV-UHFFFAOYSA-N) 1-3-Dimethyl-2-imidazolidinon (CYSGHNMQYZDMIA-UHFFFAOYSA-N) 1-(3-Chlorophenyl)-piperazin (VHFVKMTVMIZMIK-UHFFFAOYSA-N)