Determination of Glyphosate, Aminomethylphosphonic Acid, Perchlorate and 5 Disinfection By-Products in Drinking Water by Ion Chromatography-Tandem Mass Spectrometry

To achieve green, rapid, and highly sensitive simultaneous detection of glyphosate (GLY), aminomethylphosphonic acid, perchlorate (ClO₄⁻), and 5 disinfection by-products dichloroacetic acid, trichloroacetic acid (TCAA), bromate (BrO₃⁻), chlorite, and chlorate (ClO₃⁻) in drinking water, the study mentioned by the title was conducted. The drinking water samples were passed through a 0.22 μm polyethersulfone (PES) filter membrane, and the filtrate was directly introduced into the ion chromatograph-tandem mass spectrometer. The 8 target compounds were separated on Ionpac AS20 anion analytical column by gradient elution using the potassium hydroxide solution generated by an online eluent generator, ionized in negative ion mode with electrospray ionization source, detected by multiple reaction monitoring, and quantified by external standard method. It was shown that linear relationships between the mass concentrations of the 8 target compounds and their corresponding peak areas were kept in definite ranges, with detection limits in the range of 0.05-1.0 μg · L⁻¹. Test for recovery was made using standard addition method, giving recoveries in the range of 71.1%-115%, and RSDs (n=6) of the determined values ranged from 1.1% to 6.5%. The proposed method was applied to the analysis of 61 drinking water samples, and ClO₄⁻, ClO₃⁻, BrO₃⁻, TCAA, and GLY were detected at detection amounts in the range of 0.6-38.5 μg · L⁻¹.