Analysis of toxic elements in polymer samples by ICP-based techniques

Abstract

The European Standard EN 71/3 and the Directive 88/378/CEE limit the migration of some heavy metals (As, Ba, Cr, Cd, Hg, Pb, Sb and Se) and their daily bioavailability in plastics used in toy industry. Other Draft Standard Projects, also based in the later directive, limit the same parameters in plastics used for childcare articles. Previous interlaboratory studies have shown that the migration analyses of heavy metals using European Standard lack of accuracy and reproducibility. In addition, analyte concentration in these materials is too close, or even lower, than the detection limits (LOD) of the analytical techniques recommended (i.e. Flame, Hydride Generation and Cold Vapour Atomic Absorption Spectrometry). The aim of this work is to evaluate the behaviour of different sample introduction devices for the elemental polymer analysis by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). To this end, the limits of quantification (LOQs), defined as 3 times the LODs, obtained with the different devices were compared with the maximum concentration allowed by the CE Standard in the solution obtained after sample microwave digestion treatment (MCA).