Preparation and Certification of the Reference Materials, Marine Sediment for the Determination of Dioxins and Polychlorobiphenyls

The Japan Society for Analytical Chemistry has developed two new certified reference materials (CRMs) for dioxins: coplanar PCBs and 1 ~ 10 chlorinated PCB homologues. A project team has been organized to prepare 2 kinds of marine sediment and to certify the concentration of dioxins and polychlorobiphenyls. An interlaboratory comparison test was performed by participants from 24 laboratories. In a statistical analysis, the z scores in robust method were applied to reject outliers, followed by the usual statistical procedure. The presented CRMs are expected to be useful for the quality assurance and quality control of dioxins analysis.