Application of Portable X-ray fluorescence in the in-situ Testing of Heavy Metals in Historic Lead-Zinc Smelting Area in Yungui Plateau of China

Abstract

Purpose Which kind of elements could be determined by the portable X-ray Fluorescence (PXRF) analyzer in field conditions? How about the accuracy of the results? It is necessary to conduct some researches in order to well understand the application of PXRF which is regarded as a new kind of in-situ measurement method. Methods A set of 221 farmland soil samples were collected within a basin once it has been a lead-zinc smelting base. PXRF was used for field detection at all sample sites, then the soil samples were brought back to the laboratory to be analyzed again by atomic absorption spectrometry (AAS), paired T test and linear regression were conducted to analyze the difference and correlation between the result of PXRF and AAS methods. Results There was little difference and high correlation between PXRF and AAS methods, indicating that in field conditions PXRF can effectively predict the concentrations of Pb and Zn in soil. Although there were some differences in the determinationresults of Cu, the pollution level of Cu in this study area still could be predicted. Unfortunately, PXRF method had large errors in the determination of Cd and Cr, so it was not suitable for the in-situ determination of Cd and Cr in this study area. Conclusion The concentrations of Pb and Zn in the soil of lead-zinc smelting area can be accurately monitored by PXRF, while concentrations of Cu in soil can also be predicted by PXRF in the less accuracy level, Cd and Cr should not be monitored by PXRF.