Objectives To improve the influencing factors of inductively coupled plasma mass spectrometry method for the determination of arsenic in water and to provide a new method for accurate quantitative analysis of arsenic in water.

Methods Samples were directly determined by inductively coupled plasma mass spectrometry based on collided reaction cell technology.Internal standard element of Yttrium (⁸⁹Y) was used to correct matrix interference and signal drifting; high-performance Xs interface was used to reduce non-mass spectrum interferences, and collided reaction cell technology (CCT mode) was used to eliminate mass spectrum interferences.

Results The optimal linear range of the standard curve for this method was 0~20 μg/L with a correlation coefficient of 0.9999.The detection limit of the method was 0.064 μg/L; the lowest quantitative limit was 0.19 μg/L; the relative standard deviation was 1.4%~4.0% and the recovery rate was 95.7%~104.0%. The detection results of two standard reference materials were satisfactory.

Conclusions The detection limit of the method was low; and the method was simple, fast, accurate, and suitable for accurate quantitative analysis of arsenic in water.