Determination of total As, Cd, Pb and Hg in vegetable feed : IMEP-119 proficiency test report

This report presents the results of a proficiency test round (PT, IMEP-119) of the EURL-HM focussing on the determination of total As, Cd, Pb and Hg in vegetable feed in support to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed. The PT exercise was also opened to all laboratories who wish to take part in the exercise as a way to benchmark their performance against NRLs and other laboratories. One hundred and two participants from 45 countries registered to the exercise. Only eight participants did not report their results. Laboratory results were rated using z- and zeta (ζ-) scores in accordance with ISO 13528. The relative standard deviation for proficiency assessment was set to 15 % for the total As, Cd and Pb mass fractions, and to 22 % for the total Hg mass fraction, respectively. An overall adequate performance for NRLs and feed control laboratories is shown by the percentage of satisfactory performance (expressed as z-scores). These percentages were ranging from 93 to 74 % for NRLs and from 92 to 69 %, for feed control laboratories, respectively.