M. Senila, E. Levei. , L. Senila,O. Cadar, G. Oprea, C. Roman, Comparative study of mercury determination soil and vegetable by methods base don termal decomposition –AAS and wet digestión CV-AFS, Studia Chemia, 1 (2011) 27-34.

Title: Comparative study of mercury determination soil and vegetable by methods base don termal decomposition –AAS and wet digestión CV-AFS

ABSTRACT. The aim of this study was to evaluate and compare the analytical parameters of two methods used for mercury determination from solid samples (soils and vegetables): direct  determination from solid samples by thermal decomposition - atomic absorption spectrometry (TD-AAS) with gold amalgamation and determination using wet digestion followed by measurements by cold vapor atomic fluorescence spectrometry (CV-AFS). Two commercially available mercury (Hg) analyzers were used for the study. Using direct measurement in solid sample by TD-AAS, a detection limit of 1.2 μg kg−1 and a RSD of 3.8% for 1441 μg kg−1 Hg were obtained, while by using wet digestion and CV-AFS measurement, a detection limit of 2.5 μg kg−1 and a RSD of 4.5% for 1438 μg kg−1 Hg were calculated. The accuracy of the methods was verified by the determination of mercury in certified reference materials and good agreement between found concentrations and certified values was obtained for the both methods. Five real soil samples and five vegetable samples from Baia Mare area were analyzed. The Hg concentrations in soils ranged between 653–2004 μg kg−1 using TD-AAS method and between 644-1998 μg kg−1 using CV-AFS method, while in vegetables the concentrations ranged between 4,60-53,4 μg kg−1 using TD-AAS method and between 4,32-55,8 μg kg−1 using CV-AFS method. According to the t- Test and regression analysis, no significant statistical difference between the datasets obtained by the two methods was found.

Keywords: mercury determination, soil samples, vegetable samples, TD-AAS, CV-AFS