Laboratory of Inorganic and Nuclear Chemistry, Division of Environmental Health Sciences, Wadsworth Center, New York State Department of Health, Albany, NY, 12237, USA; Department of Environmental Health Sciences, School of Public Health, The University at Albany, State University of New York, Rennselaer, NY, 12144, USA.
Westat, Rockville, MD, 20850, USA.
Environ Res. 2021 Feb;193:110302. doi: 10.1016/j.envres.2020.110302. Epub 2020 Oct 10.
Harmonization and traceability are related metrological principles that are indispensable to assuring measurement comparability across different biomonitoring studies. The Children's Health Exposure Analysis Resource (CHEAR) was established in 2015 with six laboratories providing environmental exposure measurements on biospecimens. To ensure harmonization across studies for trace elements, CHEAR used a multi-faceted approach that included: 1) an initial interlaboratory validation exercise based on the analysis of certified blood and urine reference materials; 2) frequent participation in an established interlaboratory proficiency program for trace elements; and 3) analysis of a common pool of well-characterized biological reference materials with each analytical batch. Method accuracy and precision were established for each laboratory via analysis of NIST SRM 955c Toxic Elements in Caprine Blood, SRM 2668 Toxic Elements in Frozen Human Urine and SRM 3668 Mercury, Perchlorate, and Iodide in Frozen Human Urine. The differences among the six laboratories for As, Cd, Hg, and Mn in urine and Cd, Hg, and Pb in whole blood were judged to be fit-for-purpose. Interlaboratory performance over a 5-year period demonstrated an improvement in performance, such that for 2018-2019, >99% of challenges for urine As, Cd, Hg, and Mn, and 95% for whole blood Cd, Hg, Pb, and Mn, were found to be satisfactory. The CHEAR common reference materials were analyzed by at least 5 laboratories for 22 elements in urine and 13-14 elements in whole blood, thus providing a rich source of data to assess intra- and inter-run performance. The suite of trace elements with assigned values in both blood and urine matrices are more comprehensive than similar reference materials from other sources, and is reflective of the concentrations necessary to support biomonitoring studies. While some areas for future improvement were identified, significant progress was made to improve harmonization of trace element measurements in biological matrices among the CHEAR network labs.
协调和可溯源性是相关的计量学原则，对于确保不同生物监测研究之间的测量可比性是不可或缺的。儿童健康暴露分析资源（CHEAR）于 2015 年成立，有 6 个实验室提供生物标本的环境暴露测量。为了确保研究之间的微量元素协调，CHEAR 采用了多方面的方法，包括：1）基于对认证血液和尿液参考物质的分析，进行初始的实验室间验证；2）频繁参与已建立的微量元素实验室间能力验证计划；3）与每个分析批次一起分析一批特征良好的生物参考物质。通过分析 NIST SRM 955c 山羊血液中的毒元素、SRM 2668 冷冻人尿中的毒元素和 SRM 3668 冷冻人尿中的汞、高氯酸盐和碘化物，为每个实验室建立了方法的准确性和精密度。对尿液中的 As、Cd、Hg 和 Mn 以及全血中的 Cd、Hg 和 Pb，6 个实验室之间的差异被认为是适合目的的。在 5 年期间，实验室间的性能得到了改善，例如，2018-2019 年，尿液中 As、Cd、Hg 和 Mn 的挑战中有超过 99%，全血中 Cd、Hg、Pb 和 Mn 的挑战中有 95%是令人满意的。CHEAR 常见的参考物质由至少 5 个实验室分析，尿液中有 22 种元素，全血中有 13-14 种元素，因此提供了丰富的数据来评估内和运行性能。在血液和尿液基质中都有赋值的微量元素套件比来自其他来源的类似参考物质更全面，反映了支持生物监测研究所需的浓度。虽然确定了一些未来改进的领域，但在 CHEAR 网络实验室中，微量元素测量的协调得到了显著改善。
