Arsenic Determination in Plant Samples by Hydride Generation and Axial View Inductively Coupled Plasma Atomic Emission Spectrometry

Abstract.

The present work describes a study on the determination of arsenic in plant samples with hydride generation coupled with an axial view inductively coupled plasma atomic emission spectrometer. The accuracy of the measurements was not affected by elements present in high concentrations in the plant matrix (K, Ca, Mg, and P). Interference from transition metals was not observed either. When using real samples (maize and oak leaves) with standard additions, a decrease in the recoveries was sometimes observed when using KI to reduce As(V) to As(III), which reached 13.5% in the most unfavourable case. The use of a mixture containing KI and ascorbic acid is recommended. The accuracy of the method was verified using three certified reference materials. No statistically significant differences were observed between the measured concentrations and the certified values. The optimized method was found to be sensitive (detection limit: 0.1 µg L⁻¹) and reliable. The results obtained under routine conditions over a period of several months also demonstrated its reproducibility.