AN ATTEMPT TO CERTIFY PHENYLTIN COMPOUNDS IN A MUSSEL REFERENCE MATERIAL

Organotin contamination of the marine environment can be considered on e of the main environmental problems in the last 20 years. Starting fr om the 'Arcachon case', monitoring campaigns have been carried out wor ldwide in order to evaluate the concentration levels of these compound s in the marine environment. In 1987 the EC Standards, Measurements an d Testing Programme (formerly BCR) started a 'tin speciation' project to assess and improve the quality of measurements in this field and. t o make available reference materials. Ten years of study within the fr amework of this project have produced results in the fields of method development and production of reference materials, particularly for bu tyltins. The quality of the phenyltin analytical results was lower tha n for butyltins and further efforts are still needed. To overcome this shortfall, the last certification campaign was aimed towards the cert ification of phenyltins, as well as butyltins, in a candidate mussel c ertified Reference Material. The results of the homogeneity and stabil ity tests for phenyltins and of the certification campaign are present ed here. The preparation of the material and the analytical methods us ed in the certification campaigns are also described. The certificatio n of phenyltins was hindered by their lack of long-term stability; nev ertheless, the exercise provided information about the state-of-the-ar t of phenyltin measurements in biological samples. (C) 1998 John Wiley & Sons, Ltd.