Determination of Pb (Lead), Cd (Cadmium), Cr (Chromium), Cu (Copper), and Ni (Nickel) in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry  Wen-Si Zhong, Ting Ren, Li-Jiao Zhao  Journal of Food and Drug Analysis  Volume 24, Issue 1, Pages 46-55 (January 2016) DOI: 10.1016/j.jfda.2015.04.010 Copyright © 2015 Terms and Conditions

Fig. 1 Pyrolysis and atomization temperature curves for lead, cadmium, chromium, copper, and nickel. 1, no matrix modifier; 2, 3, and 4: with 2 μL, 5 μL, and 10 μL of modifier, respectively. (10 g/L NH4H2PO4 solution for Pb and Cd; 1 g/L Mg(NO3)2 solution for Cr; 0.5 g/L Mg(NO3)2 solution for Cu and Ni). Cd = cadmium; Cr = chromium; Cu = copper; Ni = nickel; Pb = lead. Journal of Food and Drug Analysis 2016 24, 46-55DOI: (10.1016/j.jfda.2015.04.010) Copyright © 2015 Terms and Conditions

Fig. 2 The nonlinear standard curves for lead, cadmium, chromium, copper, and nickel. Cd = cadmium; Cr = chromium; Cu = copper; Ni = nickel; Pb = lead. Journal of Food and Drug Analysis 2016 24, 46-55DOI: (10.1016/j.jfda.2015.04.010) Copyright © 2015 Terms and Conditions

Fig. 3 Lead, cadmium, chromium, copper, and nickel contents in tea samples determined with high-resolution continuum source-graphite furnace atomic absorption spectrometry. Cd = cadmium; Cr = chromium; Cu = copper; Ni = nickel; Pb = lead. Journal of Food and Drug Analysis 2016 24, 46-55DOI: (10.1016/j.jfda.2015.04.010) Copyright © 2015 Terms and Conditions

Fig. 4 Distribution of the lead, cadmium, chromium, copper, and nickel contents in the seven types of tea. Cd = cadmium; Cr = chromium; Cu = copper; Ni = nickel; Pb = lead. Journal of Food and Drug Analysis 2016 24, 46-55DOI: (10.1016/j.jfda.2015.04.010) Copyright © 2015 Terms and Conditions