BCR (NON-CERTIFIED) REFERENCE MATERIALS FOR DIOXINS AND FURANS IN MILK POWDER

Milk powders spiked with different quantities of polychlorinated diben zo-p-dioxins (PCDD) and dibenzofurans (PCDF) have been prepared by bot h freeze drying and spray drying. In 1991, the freeze dried batches we re used in a BCR intercomparison. The spray dried batches have now bee n compared to the freeze dried ones. The obtained results show that: t here is no significant difference between the materials; the recoverie s of the added amounts of D48, D54, D66, D67, D70, F83, F94, F114, F11 8, F121 and F130 are of the order of 90%. On this basis, assigned valu es are proposed for the spray dried materials which will became availa ble as a set of three (non-certified) BCR reference materials (RM 532, RM 533, RM 534).