Certification of reference materials for Cd, Cr, Hg and Pb in polypropylene

Abstract

Two reference materials, at relatively low and high concentrations (GBW08404 and GBW08405), for analysis of the mass fractions of Cd, Cr, Hg and Pb in polypropylene were developed. The reference materials were prepared by doping blank polypropylene base material with Cd, Cr, Hg and Pb in the form of oxides, salts or pigments. Homogeneity and stability studies were performed by inductively coupled plasma mass spectrometry. The certification of the four analytes was carried out by isotope-dilution mass spectrometry (IDMS) with microwave-assisted digestion. Combined uncertainties were calculated from the IDMS uncertainty evaluation budget and the uncertainty of the homogeneity. The mass fractions of Cd, Cr, Hg and Pb of the two certified reference materials (CRMs) were from 8 to 1,000 mg kg(-1). The two samples were also used in an interlaboratory comparison scheme in which National Institute of Metrology, China, National Metrological Institute of Japan and Korea Research Institute of Standards and Science participated. The agreement of the comparison results proved that the certification procedure of the CRMs is valid and that the certified values of Cd, Cr, Hg and Pb are accurate and reliable.

Development of reference procedures for the quantification of toxic metals and S in plastics

“…Recently published data on the certification of Cd, Cr, Hg and Pb in polypropylene stated expanded uncertainties between 1 and 3.5% for IDMS analysis. 10 The expanded uncertainties being achieved with the reference procedures described here are lower by nearly a factor of 10 for Cd, Cr and Pb and by a factor of more than 2 for Hg.…”

“…Recently published data for the certification of a polypropylene reference material showed expanded uncertainties between 1 and 3.5%, which are close to the requirement as stated above, but still leave space for further improvement. 10 The calibration technique which is suited best for the quantification of trace elemental mass fractions is undoubtedly isotope dilution mass spectrometry (IDMS). 11 When performed properly, it offers smallest measurement uncertainties, which in former terms means highest accuracy and highest precision.…”

Atomic spectrometry update. Industrial analysis: metals, chemicals and advanced materials

“…One has a relatively low level of the analytes Cd, Cr, Hg and Pb in polypropylene (GBW 08404), whereas the other has higher concentrations (GBW 08405). 237 The authors of the report, Feng et al described how the materials had been prepared by doping blank materials with the analytes in the form of oxides, salts or pigments. The concentrations of the analytes were determined by microwave assisted digestion followed by ID-MS detection.…”

The production of polymer reference materials for microanalysis with high homogeneity by a 3D printing method

“…1 Specifically, the contents of As, Br, Cd, Cl, Cr, Hg, Pb, S, and Sb elements in products are strictly controlled because they can be toxic to humans, animals and the environment. 2 To accurately measure these elements, relevant certified reference materials (CRMs), such as ERM EC680m, 681m (IRMM, Belgium), 3 GBW08404-08411, GBW(E)081121-081123, GBW(E)083090 and GBW(E)083091 (NIM, China), 4 were developed. Such samples are usually analyzed by wet chemical methods.…”