Atomic spectrometry update. Clinical and biological materials, foods and beverages

This is the 25th Update to have been prepared with the title Clinical and Biological Materials, Foods and Beverages. There has been much change in the content with new techniques having emerged, more elements attracting interest, different applications being featured and fine work coming from countries that previously made little or no contribution to these topics. The volume of work surveyed each year has increased approximately five-fold although the length of the review has not grown proportionately. The features this year include the traditional favourites of lead, mercury and selenium. While it may have been thought of as no longer a problem element there is growing interest in aspects of iodine nutrition and its metabolism. Use of gadolinium-containing contrast agents for NMR has suddenly emerged both from clinical and environmental perspective. Work mentioned in this review considers the stability of agents in serum as well as techniques for measurement. An interference on the measurement of selenium has been spotted but not yet reported in the clinical literature. Speciation work continues unabated. Faecal material was taken to investigate the formation of As species and, in one particularly dedicated piece of work, new mixed As–S and As–Se species were found by headspace sampling with GC separation and simultaneous ES-MS and ICP-MS. Yet more selenium species were discovered and attention has spread to antimony. An intriguing report describes the production of a volatile intermediate, CH₃HgH, during the determination of MeHg by CVAAS. Allied to speciation is the description of extraction methods using sonication and/or enzymes aimed at preserving in vivo chemical structures. The use of nails as a test material is growing, tempered perhaps by an indication that there are considerable inter-finger and inter-toe concentration variations. Alarmingly high concentrations of several elements were found in urine samples from inhabitants in a copper mining area of the Democratic Republic of Congo. One of the most unlikely pieces of work involved the measurement of lead in bone of grouse shot in Scotland and Yorkshire. Exposure was said to derive from the habit of birds ingesting used shots found on the ground. Given the ultimate fate of the birds and how they will be killed, their previous dietary history is probably unimportant.