Breakthrough development for quantitative analysis of total metals in soil by portable HDXRF

Heavy metal contamination from industrialization in developing countries is an important environmental issue today. Hand Held X-ray Fluorescence (HHXRF) analysis recently become a powerful tool to screen metal contamination... [ view full abstract ]

Heavy metal contamination from industrialization in developing countries is an important environmental issue today. Hand Held X-ray Fluorescence (HHXRF) analysis recently become a powerful tool to screen metal contamination in brown field sites. However, HHXRF on site analysis does not meet the needs in many contamination site survey and risk assessments due to two major reasons: 1) Not accurate enough to provide good assessment of contamination site, and 2) poor detection limits at low level contamination survey, especially for As, Cd, Ni and Hg contamination sites. Currently, comprehensive site assessment is heavily dependent on field sample collection and lab analysis. The large scale sample collection and lab analysis is a severe bottle neck for environmental cleanup in both cost and resource aspects.
Recently, a portable soil metal analyzer has successfully developed base on an innovative multiple monochromatic focused beams XRF technology, called high-definition XRF (HDXRF). This new analyzer is designed with miniature doubly curved crystal optical system coupled with a miniature x-ray tube. It provides superior detection limits for low level metal analysis due to the use of monochromatic excitation. In this paper, in-depth data set of various soil standards and soil samples from actual survey sites will be presented. Comparison between HDXRF data and lab ICP results will also summarized. It is demonstrated that on site non-destructive quantitative analysis for low level metals (1-10ppm range) in soil has been achieved for the first time.