QUASIMEME - A PRELIMINARY-STUDY ON THE EFFECTS OF SAMPLE HANDLING ON THE MEASUREMENT OF TRACE-METALS AND ORGANOCHLORINE RESIDUES IN MUSSELS

As part of the development of quality measurement of trace metals and organochlorine residues in marine biota, the QUASIMEME Project underto ok an interlaboratory study to determine the magnitude of the errors a ssociated with the sample handling of mussels (Mytilus edulis) prior t o analysis. Mussels were distributed to participating laboratories whi ch homogenized and freeze-dried five pools of 10 mussels. Each pool wa s analysed both by the participants and by a reference laboratory. Sys tematic errors resulting from the freeze drying and from contamination during analysis for the trace metals, particularly lead and organochl orines, were identified. In general, the errors associated with the sa mple preparation were of similar magnitude to the final measurement of the trace metals, whereas the errors for the measurement of the chlor obiphenyls and the organochlorine pesticides still dominated the overa ll variance and bias for the analysis. (C) 1997 Published by Elsevier Science Ltd. All rights reserved.