The pilot Global Assessment of Laboratories Analysing Mercury was organized in summer 2018 (August-October) as a first round of the global proficiency test. Participation was by invitation only and invitees were selected from the Mercury Laboratory Databank organized by UN Environment, Chemicals and Health Branch. There were 80 laboratories invited, 42 laboratories from 29 countries registered for the global assessment and 38 laboratories from 28 countries worldwide delivered results.
Test materials for total mercury analyses used included three matrices: (i) test solution of analytical standards and (ii) naturally contaminated samples of biota: (a) fish samples, and (b) human scalp hair samples.
Total mercury was analysed in all test samples and results provided by laboratories are shown in this report. No matrix was compulsory in this pilot laboratory assessment, therefore there was no full participation in analyses of individual matrices. Almost 90% of all laboratories analysed the standard solution and 80% of the delivered results presented satisfactory z-score. Lower amount, 84% of all laboratories analysed biota sample (fish) and almost 85% were with satisfactory z-scores outcome. 73.7% laboratories analysed human scalp hair and there were 82% of satisfactory z-scores outcome.
It is quite encouraging to see a good agreement of reported data with reference values for the individual test samples provided by both developed and developing countries.
