Author/Editor     Horvat, M; Mandić, V; Liang, L; Bloom, NS; Padberg, S; Lee, Y-H; Hintelmann, H; Benoit, J
Title     Certification of methylmercury compounds concentration in marine sediment reference material, IAEA-356
Type     članek
Source     Appl Organomet Chem
Vol. and No.     Letnik 8
Publication year     1994
Volume     str. 533-40
Language     eng
Abstract     An intercomparison exercise was organized between seven laboratories using various isolation procedures (extraction, distillation, ion-exhange and alkaline digestion) and detection systems (CV AAS, cold vapour atomic absorption spectroscopyl; CV AFS, cold vapour atomic fluorescence spetroscopy); GC, ECD, gas chromatrography eletron capture detector and HPLC with CV AFS detection) for determination of methylmercury compounds in sediment sample. All certification criteria were fulfilled and therefore the value for total concentration of methylmercury compounds was certified to be 5.46 ng g-1, with a 95% confidence interval from 5.07-5.84 ng g-1. The acceptable range, calculated as two times the confidence interval of the mean is therefore from 4.68-6.23 ng g-1. This is the first sediment reference material ever to be certified for concentration of methylmercury compounds. Comparison of the data obtained by various methodologies has shown that the most critical step is the isolation of methylmercury compounds from binding sites. Acid leaching only cannot release mthylmercury compounds quantitatively. Total release of methylmercury compounds could only be achieved by alkaline digestion or distillation. This simple intercomparison exercise has shown that since large numbers of laboratories world-wide are performing methylmercury compound analyses using various improved and specific separation methods and sensitive detection systems, certification of methylmercury compounds in defferent biological and environmental samples should not be a problem in the future.
Descriptors     GEOLOGIC SEDIMENTS
METHYLMERCURY COMPOUNDS
SEAWATER
REFERENCE STANDARDS
CHROMATOGRAPHY, GAS