Direct speciation analysis of organophosphorus environmental pollutants in water by HPLC-ICPMS/MS

Abstract

A new and optimized HPLC-ICPMS/MS method for the simultaneous determination of five of the most common phosphorous environmental pollutants in various water matrices has been developed, including aminomethylphosphonic acid (AMPA), glufosinate, glyphosate, fosamine, and ethephon. We show that the ICPMS/MS confers an average of 20-fold improvement in the detection limit (0.1–0.3 µg P L−1) relative to comparable methods based on single quadrupole ICPMS detection, without the incorporation of any sample purification or preconcentration step. The method was validated by determining the intra-day repeatability (< 6%), inter-day repeatability (< 10%) and recovery (86–112%) of 4 levels of spiking (5.0–250 µg L−1). The developed method involved utilizing the carbon enhancement effect which yielded up to 3-fold increase in sensitivity. A signal suppression effect exerted by the carbonate content of the analyzed water samples was identified, and should be generally taken into consideration when analyzing untreated hard water samples by HPLC-ICPMS. The developed method can be an important contribution in order to keep up with increasingly more stringent future regulations for the levels of the analyzed pollutants given their rising health concerns.