Accuracy of biological trace-element determinations.

Mounting evidence suggests that the accuracy of much of the published information on trace-element concentrations in biological matrices leaves much to be desired. Potential sources of error are: (a) inadequate sample collection and preparation (sampling errors); and (b) inaccuracies at the moment of the measurement (measurement errors). Probably much of what has been maintained on trace elements in human health and disease in the past will have to be revised in the future.