Lead in feed incident--multi-element analysis of cattle feed and tissues by inductively coupled plasma-mass spectrometry and co-operative quality assurance scheme for lead analysis of milk.

Contaminated cattle feed was imported into the UK in 1989 and resulted in lead toxicity in some animals. Rapid analyses for lead and several other possible contaminating elements were required for feed and cattle tissues. Microwave dissolution of samples with measurement by ICP‐MS was used for multi‐element determinations. Lead was found to be the major contaminant. Lead levels in milk samples were measured by several laboratories during the crisis and an analytical quality assurance scheme was devised to monitor the quality of the data. The scheme allowed any poorly performing laboratories to be rapidly identified and excluded from the survey.