Variables: dissolved_oygen dissolved_organic_carbon total_organic_carbon pH Keywords: MetFrag micropollutants high resolution mass spectrometry land use Substances: 18-beta-Glycyrrhetinic acid (MPDGHEJMBKOTSU-YKLVYJNSSA-N) 1-(3-Trifluoromethylphenyl)-piperazine (KKIMDKMETPPURN-UHFFFAOYSA-N)