Determination of aluminium in serum: findings of an external quality assessment scheme

The analytical performance of laboratories participating in the serum aluminium programme of the Guildford Trace Element Quality Assessment Scheme has been evaluated. The considerable disparity between reported results was not attributable to the nature of the samples distributed, nor to the standard aluminium solutions used in different laboratories. All laboratories used electrothermal atomic absorption spectrometry but sample preparation procedures and temperature programmes varied enormously. While some laboratories performed better than others in the scheme, and the standard of analysis appears to be improving with time, no laboratory showed consistent acceptable performance.