Harmonized Quality Assurance/Quality Control Provisions for Nontargeted Measurement of Urinary Pesticide Biomarkers in the HBM4EU Multisite SPECIMEn Study

Abstract

A set of quality assurance/quality control (QA/QC) criteria for nontargeted measurement of pesticide exposure markers in a large-scale study of human urine has been proposed and applied across five laboratories within the HBM4EU project. Quality control material, including reference standards and fortified pooled urine samples (QC urine) were prepared in a centralized way and distributed across participants to monitor analytical performance and consistency of the liquid chromatography coupled to high-resolution mass spectrometry data generated with a harmonized workflow. Signal intensities, mass accuracy, and retention times of selected QA/QC markers covering a broad range of physicochemical properties were monitored across QC solvent standards, QC urine samples, study urine samples, and procedural blanks, setting acceptance thresholds for repeatability and accuracy. Overall, results showed high repeatability of the collected data. The RSDs of the signal intensities were typically below 20–30% in QC and study samples, with good stability of the chromatographic separation (retention time drift within 2–4 s intrabatch and 5 s interbatch) and excellent mass accuracy (average error < 2 ppm). The use of the proposed criteria allowed for the identification of handling errors, instrumental issues, and potential batch effects. This is the first elaboration of harmonized QA/QC criteria applied across multiple laboratories to assess the quality of data generated by nontargeted analysis of human samples.

Identification and Prioritization of Environmental Organic Pollutants: From an Analytical and Toxicological Perspective

“…On the contrary, a standardized QA/QC protocol is lacking in NTS analysis, probably because NTS is a developing methodology for a broader range of analytes and the harmonization of analytical procedures is more challenging. The issue has attracted attention by the scientific community, and some consensus and definitive reference QA/QC protocols have been recommended recently. − These protocols have commonalities in several crucial points that should be considered, involving sample collection and storage, internal standards, sample pretreatment, chromatographic separation, data acquisition via MS platforms, data preprocessing, and reporting of results. More importantly, analyte coverage, recovery, reproducibility, and quantitative stability are listed as the most critical criteria.…”

“…Authorized standard solutions, fortified pooled urine samples, study urine samples, and procedural blanks were analyzed by a harmonized analytical workflow. Signal intensities, mass accuracy, and RTs of the selected markers were further checked to set acceptance thresholds for repeatability and accuracy (e.g., RT shift ≤ 0.3 min, signal intensity decrease of native markers ≤ 50%, and signal intensity variation ≤ 2-fold across batches), which can be used to recognize handling errors, instrumental failures, and potential batch effects …”

“…Signal intensities, mass accuracy, and RTs of the selected markers were further checked to set acceptance thresholds for repeatability and accuracy (e.g., RT shift ≤ 0.3 min, signal intensity decrease of native markers ≤ 50%, and signal intensity variation ≤ 2-fold across batches), which can be used to recognize handling errors, instrumental failures, and potential batch effects. 242 5.2.5. Data Mining based on Molecular Features.…”