Last Updated: 05-03-2020 12:51
Within the frame of the HBM4EU project, an External Quality Assurance Scheme (EQUAS) was organised on the determination of four OPFR biomarkers in urine. This was the 4th ICI/EQUAS round for this substance group within the HBM4EU program.
In total, 14 laboratories were invited for this 4th ICI/EQUAS and six laboratories (including three expert laboratories) submitted results. Four labs were able to report results for all four parameters and two labs reported results for three parameters.
In December 2019, each participant received one tube of burdened control materials of human urine (low level – level 1), one tube of burdened control materials of human urine (high level – level 2). The biomarker concentrations were approximately in the range of 2-6 µg/L and 8-25 µg/L for level 1 and level 2, respectively. The concentrations were chosen according to the review of relevant data on the occurrence of OPFRs in urine of the European population published mostly during the last five years.
A homogeneity assessment showed that both materials were sufficiently homogeneous for EQUAS testing. No issues with stability of testing materials occurred for OPFRs.
The determination of expert value based on results from expert laboratories was not possible only for BCEP, because the minimum number of expert results wasn´t reached for this biomarker.
The evaluation of laboratory performance using Z-scores was performed for DPHP, BDClPP and BClPP for the first time. Most laboratories showed well comparable results for BCEP too, although a regular evaluation was not possible. The achieved results for BCEP are present in the report for further comparison between participants and expert labs.