Precision criteria of methods for the quantification of metals migrated from Food Contact Materials: Pre-validation data derived from ILCs on elements representative for plastics and ceramics

Abstract

Precision criteria for the quantification of metals in acetic acid 3% and acetic acid 4% migration solutions for different analytical techniques were calculated and are presented in this report. They were derived from two interlaboratory comparisons (ILC03/04 2014) data, including repeatability and reproducibility standard deviations. Three groups of analytical techniques were identified from the ILCs: Inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma Optical emission spectrometry (ICP-OES) and atomic absorption spectrometry (AAS). AAS included graphite furnace (GF-AAS) and flame (F-AAS). Precision criteria were calculated applying robust statistic methods with algorithms A and S (ISO 5725-5 and ISO 13528) and DIN 38402 A45 (Q-method/Hampel-estimator) The robust means calculated according to both algorithms were checked for significant difference (student's t-test) and equivalence test. Relative repeatability standard deviations were very low generally less than 2% and reached 4.4% only for Pb in acetic acid 4%. Relative reproducibility standard deviations for Pb were around 10% for ICP-MS and ICP-OES techniques and 16% for AAS. Relative reproducibility standard deviations for Cd were around 5%, 10% and 20% using respectively ICP-MS, AAS or ICP-OES techniques. For other elements the relative reproducibility standard deviations obtained were for most of the cases less than 10%. From the comparison study it was possible to establish with the exception of Fe, for all elements of the two ILCs in both solutions (corresponding to elements from ceramics and elements from plastics) the analytical techniques were generally equivalent and not significantly different at the concentrations investigated.JRC.I.1-Chemical Assessment and Testin