Keywords: monitoring Substances: 5-Methylpyridine-3-carboxylic-acid (DJDHHXDFKSLEQY-UHFFFAOYSA-N) 1-Methyl-Benzotriazole (HXQHRUJXQJEGER-UHFFFAOYSA-N) 1-Hydroxy-Benzotriazole (ASOKPJOREAFHNY-UHFFFAOYSA-N) Acetochlor-ESA (HXAIQOCRALNGKB-UHFFFAOYSA-N)