A certified reference material (CRM), KRISS CRM 108-10-003, has been developed for analysis of acrylamide in potato chips, as a representative of carbohydrate-rich food cooked in high-temperature oil. The material was prepared by grinding commercially available potato chips to a paste which was then homogenized, bottled in 15-g units, and stored at -70 °C. Certification, homogeneity and stability testing, were carried out by liquid chromatography-isotope-dilution mass spectrometry (ID-LC-MS). A single ID-LC-MS measurement was performed for each of 10 selected units for certification and homogeneity assessment. The mean measurement result for the 10 bottles, 0.455 ± 0.012 mg kg(-1), was assigned as the certified value of the CRM. The between-bottle homogeneity was 0.8% of the certified value. The within-bottle homogeneity, tested by measuring three replicate sub-samples from each of three randomly selected bottles, was similar to the between-bottle homogeneity. The stability of the CRM under storage conditions (-70 °C) was tested for 21 months and no change in the acrylamide content was observed within the measurement uncertainty. Stability of the CRM at -20 °C (storage at user's site) and room temperature (for regular use and transportation) was also tested. Also presented is the newly designed procedure for evaluating the uncertainty of the certified value for the characterization scheme used in this study.

The key comparison CCQM-K34 was organized jointly by the inorganic and electrochemistry working groups of the CCQM as a follow-up to the pilot study CCQM-P36 to test the abilities of the metrology institutes to measure the amount content of acid in solid weak acids. The Slovak Institute of Metrology acted as the coordinating laboratory, and seven NMIs expressed interest in participation. All participants used constant current coulometry at different levels of sophistication. In general very good agreement of the results was observed; some possible problems were highlighted.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCQM.

Accurate measurement of the hazardous elements in cosmetics is considerably important in response to cosmetics safety issues. A sample preparation method using microwave-assisted acid digestion combined with double isotope dilution inductively coupled plasma/mass spectrometry (ID ICP-MS) was used for certification of the hazardous elements Cd, Hg and Pb in cosmetic powder samples. The HF-free sample preparation method was validated and applied to analyse Cd and Pb in cosmetic powder. The Hg content in the sample was determined by employing a fast valve sample introduction system to resolve the severe memory effect in Hg analysis. Homogeneity and stability were also evaluated. The certified values of Cd, Hg and Pb were (24.8 ± 1.3) mg/kg, (0.648 ± 0.065) mg/kg and (24.55 ± 0.31) mg/kg, respectively. The relative combined standard uncertainty was 2.7 % for Cd, 5.1 % for Hg and 0.62 % for Pb. The detailed procedure for certification and evaluation of the associated uncertainty is also presented. The proper use of the developed CRM for quality control and method validation in testing laboratories and the cosmetics industry is expected to significantly improve the reliability and quality of test results for hazardous elements in cosmetics, thereby contributing to cosmetics safety.

The key comparison CCQM-K96 was organized jointly by the inorganic and electrochemistry working groups of CCQM to test the abilities of the metrology institutes to measure the amount content of dichromate. Slovak Institute of Metrology with help of KRISS acted as the coordinating laboratories. Eight NMIs took part in the comparison. All participants used high accuracy constant current coulometry. Good agreement of the results was observed.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

CCQM-K125 was organized by the Inorganic Analysis Working Group (IAWG) of CCQM to assess and document the capabilities of the national metrology institutes (NMIs) or the designated institutes (DIs) to measure the mass fractions of trace elements (K, Cu and I) in infant formula. Government Laboratory, Hong Kong SAR (GLHK) acted as the coordinating laboratory. In CCQM-K125, 25 institutes submitted the results for potassium, 24 institutes submitted the results for copper and 8 institutes submitted the results for iodine. For examination of potassium and copper, most of the participants used microwave-assisted acid digestion methods for sample dissolution. A variety of instrumental techniques including inductively coupled plasma mass spectrometry (ICP-MS), isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS), inductively coupled plasma optical emission spectrometry (ICP-OES), atomic absorption spectrometry (AAS), flame atomic emission spectrometry (FAES) and microwave plasma atomic emission spectroscopy (MP-AES) were employed by the participants for determination. For analysis of iodine, most of the participants used alkaline extraction methods for sample preparation. ICP-MS and ID-ICP-MS were used by the participants for the determination. Generally, the participants' results of CCQM-K125 were found consistent for all measurands according to their equivalence statements. Except with some extreme values, most of the participants obtained the values of di /U(di ) within ± 1 for the measurands. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).