Ultrasonic slurry sampling combined with total reflection X-ray spectrometry for multi-elemental analysis of coastal sediments in a ria system

An increased concern on environmental issues has arisen in recent decades. Human activities have a great impact on the environment, efficient methodologies being needed for quick assessment of possible contamination sources and their effects. This paper describes a fast method for analysis of sediments by Total Reflection X-ray Fluorescence (TXRF) using a simple and rapid sample preparation approach, i.e., Ultrasonic Probe Slurry Sampling (UPSS), as an alternative to digestion. UPSS involves minimal consumption of sample and reagents within the range of microanalysis. A case study focused on a coastal area (Ria of Arousa, NW Spain) is presented. The simultaneous determination of 10 elements (Ti, V, Mn, Fe, Cu, Zn, As, Rb, Sr and Pb) was accomplished by UPSS-TXRF. Method validation was performed by means of several certified reference materials. Distribution patterns, natural background levels and enrichment factors that are indicative of contamination were obtained. Application of principal component analysis (PCA) allowed assessing the origin of trace metals in sediments of the Ria of Arousa.