Trace Analysis of Toxic Elements in Surface and Drinking Water by Combined AAS Techniques Application Note · novAA 800

Introduction

Safe drinking water is essential for health. Even low concentrations of toxic elements can be harmful if contaminated water is consumed regularly over a long period of time. Many groundwater sources supplying public and private wells contain a high concentrations of naturally occurring arsenic. Lead contamination can be caused, for example, by slow dissolution of lead water pipes. In addition, groundwater and surface water can be contaminated with toxic elements through environmental pollution. Therefore, strict regulations apply to the control of drinking water, such as the Drinking Water Directive of the European Commission, the U.S. EPA National Primary Drinking Water Regulations (NPDWR), or the German Drinking Water Regulation (TrinkwV). The limits for the most toxic elements are usually regulated from 1 to 10 µg/L. Atomic absorption spectroscopy with graphite furnace and hydride technology meets the high requirements of drinking water analysis, such as lowest detection limits and high accuracy. It is simple, robust, and suitable for routine use by means of automation. The hydride system HS60 with flow injection allows an automated sample processing with detection limits down to 0.05 µg/L for the hydride forming elements. With the integrated gold-collector, mercury can be enriched and measured down to 0.02 µg/L. For even greater sensitivity, the so-called HydrEA technique can be used. This combination of graphite furnace AAS and hydride technology provides in-situ enrichment of mercury as well as the hydride forming elements arsenic, antimony, and selenium inside the graphite tube. Thus, the technique allows trace element analysis with detection limits as low as 0.005 µg/L.