Special Issues-11-01-2011

This article describes a way to measure 226Ra using inductively coupled plasma–mass spectrometry (ICP-MS) rather than the conventional method of gamma spectroscopy, taking into account an undocumented interference (207Pb19F) that is caused by the requirement to use hydrofluoric acid during sample preparation. The unusually high Pb levels observed in a number of soil samples caused significant interferences at the very low concentrations of 226Ra that were measured. The expected 208Pb18O interference was insignificant under optimized instrument conditions.

The direct analysis of seawater by inductively coupled plasma–mass spectrometry (ICP-MS) is notoriously difficult because of the high matrix content of the sample that leads to both spectroscopic (for example, polyatomic interferences) and nonspectroscopic interferences (for example, signal suppression). Additionally, the low target concentration levels demand a noncontaminating, robust sample introduction technique. The latest ICP-MS techniques provide high-throughput methods that are able to process large numbers of samples presented for analysis.

The current United States Pharmacopeia (USP) General Chapter <231> "heavy metals limit test" will be replaced by new instrumental methods, USP <232> (Limits) and <233> (Procedures), in 2013.

This study focuses on the use of inductively coupled plasma–mass spectrometry (ICP-MS) in Chinese laboratories for measuring toxic, essential, and nutritional elements in foods. In particular, we describe recent advances in detection systems and interference removal capabilities to provide fast and simple multielement analysis over a wide concentration range for many different types of food samples.