AVALIAÇÃO DE INCERTEZA DE MEDIÇÃO NA DETERMINAÇÃO DE INTERFERENTES ENDÓCRINOS EM ÁGUA SUPERFICIAL POR CROMATOGRAFIA GASOSA COM DETECÇÃO POR ESPECTROMETRIA DE MASSAS

DOI: 10.14684/intertech.13.2014.277-284 The uncertainty was estimated for the determination of some endocrines disruptors content in superficial water using gas chromatography with mass spectrometry detection. The endocrine disruptors were extracted from superficial water by solid-phase extraction procedures, derivatisation and quantification by GC/MS. In the estimation of uncertainty, sample processing and chromatographic determination that may significantly influence the uncertainty of analytical data were considered. The results show that the method recovery and matrix-matched calibration are the two main contributors to uncertainty. The method has a relative expanded uncertainty (coverage factor k = 2,447 for 6 degrees of freedom at a 95% confidence level) of about 8 to 19% and endocrine disruptors content of approximately 4 ng.mL-1 to 2 μg.mL-1, depending on the compound. Index Terms - uncertainty measurement; endocrine disruptors; gas chromatography.