Simultaneous Determination of Multiple Elements in Environmental Water Samples by Microwave Plasma Atomic Emission Spectrometry

Vapor generated elements (As, Hg, Sb and Se) and heavy metals (Cd, Cu, Cr, Ni, Pb, Ti, V and Zn) in environmental water samples digested by the different acid were simultaneously analyzed by microwave plasma atomic emission spectrometry (MP - AES) with multi. mode sample introduction system (MSIS). The hydride generation conditions were optimized according to signal intensity of elements, and the matrix and spectral interference were investigated by the recoveries of the standard addition concentrations. Result showed that the more satisfied results of elements were obtained under the optimal reductant concentration (1.0% NaBH4) and carrier solution (5% HCl) when the samples were digested by nitrate other than hydrochloric acid. The analytical results of elements in the environmental standard samples were consistent with the standard values, and the relative standard deviation was in range of 0.4% - 3.2%. High concentration of K, Ca, Na and Mg had no influence on the measurements of the target elements, but rare earth elements had the significant spectral interference to the target heavy metals. The detection limits of the method were 1. 6-9. 8 mu g/L for most of the target elements except for Hg (6.5 mu g/L) and Se (37.1 mu g/L), which could meet the analysis requirements of environmental quality standards for surface water and standards for drinking water quality.