Certifying the contents of trimethyllead in an artificial rainwater reference material

Abstract

Certified Reference Materials are needed to verify the performance of analytical techniques used in lead speciation and for the quality control of trimethyllead determinations in environmental matrices. An interlaboratory programme has been conducted by the Standards, Measurements and Testing Programme to improve the state of the art of trimethyllead determination in urban dust and artificial rainwater. This paper describes the preparation of an artificial rainwater reference material containing trimethyllead, its homogeneity and stability studies and the analytical work performed for the tentative certification of the trimethyl- lead content at a level of ≈55 ng kg^–1 (as trimethyllead). While the analytical results obtained by the certifying laboratories were considered to be suitable for certification, doubts on the long term stability of the material did not allow certification to be recommended.