Keywords: monitoring Substances: 4-Hydroxy Diclofenac (KGVXVPRLBMWZLG-UHFFFAOYSA-N) 1-Hydroxy-Benzotriazole (ASOKPJOREAFHNY-UHFFFAOYSA-N) 2 -2 -Difluorodeoxyuridin (FIRDBEQIJQERSE-QPPQHZFASA-N) Acetochlor (VTNQPKFIQCLBDU-UHFFFAOYSA-N)