Method validation and measurement uncertainty of possible thirty volatile organic compounds (VOCs) presented in the polyethylene present in bottled drinking waters sold in Turkey

Abstract

This study was actualized for the simultaneous determination of possible thirty VOCs presented in drinking waters in Turkey by direct injection to purge and trap (PT) gas chromatography-mass spectrometry (GC-MS). It consists of selectivity, linearity, the limit of detection (LOD) and limit of quantification (LOQ), accuracy (recovery), precision, trueness, and measurement uncertainty studies. In linearity, the values of correlation coefficients (r2) for the matrix-matched calibration curves were higher than 0.998 for all analytes. This method showed high sensitivity (LOD: 0.011–0.040 μg/L; LOQ: 0.035–0.133 μg/L), quite sufficient recovery (82.6% to 103.1%) for accuracy, and acceptable precision (intra-day recovery: 81.5–104.4%, relative standard deviation (RSD): 1.04–9.81%; inter-day recovery: 92.6–104.1%, RSD: 1.15–7.52%). All the recovery and RSD values obtained below 10% are evaluated agreeable in point of the AOAC and EURACHEM/CITAC validation guidelines. The recovery percentages of all analytes in CRM changed between 80.3 and 109.9% and the RSD (%) values for each analyte obtained below 10%. The proficiency test results were satisfactory and comparable (z score less than or equal to 2.0 is no questionable or satisfactory) to those obtained by other laboratories participating in the round. The calculated percentage of relative uncertainties for each analyte changed from 2.99 to 10.10% and the major contribution to uncertainty budget arises from the calibration curve and repeatability. Therefore, the results demonstrate that this method is applicable for the determination of possible thirty VOCs in drinking waters in routine analysis for custom laboratories.