Variables: concentration Keywords: monitoring polar organic pollutant Substances: diuron (XMTQQYYKAHVGBJ-UHFFFAOYSA-N) carbendazim (TWFZGCMQGLPBSX-UHFFFAOYSA-N) mecoprop (WNTGYJSOUMFZEP-UHFFFAOYSA-N) terbutryn (IROINLKCQGIITA-UHFFFAOYSA-N)