Comparison of GC and LC determinations of hexabromocyclododecane in biological samples – Results from two interlaboratory comparison studies

In order to assess the quality and comparability of results from determinations of 1, 2, 5, 6, 9, 10-hexabromocyclododecane (HBCD) in biological samples, two interlaboratory comparison studies have been organized. Up to 13 laboratories determined either the total HBCD concentration, or concentrations of α-, β- and γ-HBCD, or both in cod liver oil, herring filet, salmon filet, butter and chicken meat. The laboratories were able to determine total HBCD concentrations in the marine samples with satisfying quality (RSD <35%). However, the analysis of samples with low HBCD contamination (