Substances: 2-n-Octyl-4-isothiazolin-3-on (OIT) (JPMIIZHYYWMHDT-UHFFFAOYSA-N) 4-Hydroxy Diclofenac (KGVXVPRLBMWZLG-UHFFFAOYSA-N) 4-Acetamidoantipyrin ( N-Acetyl-4-Aminoantipyrin 4-AAA) (OIAGWXKSCXPNNZ-UHFFFAOYSA-N) Keywords: high resolution mass spectrometry monitoring