Determination of 54 elements in lichen transplants

Abstract

Three multi-element techniques employed for analysis of lichen transplants deployed at sites in Romania with strongly differing exposure to air pollutants were compared with respect to precision and determination limits for 54 elements. The results obtained for Evernia prunastri (unexposed and 6 months’ exposure at three sites) are presented here. The techniques were energy dispersive X-ray fluorescence analysis (EDXRF), sector-field inductively-coupled plasma mass spectrometry (ICPMS), and instrumental neutron activation analysis (INAA). From an assessment of the data the EDXRF values were preferred for 3 elements (Ni, Cu, Pb), ICPMS for 18 elements (B, Mg, P, Ga, Rb, Sr, Y, Mo, Ag, Cd, In, Sn, Cs, Ba, Pr, Hg, Tl, Bi), and INAA for 23 elements (Na, Al, Cl, Ti, Cr, Co, Se, Br, I, La, Ce, Sm, Eu, Tb, Dy, Yb, Lu, Hf, Ta, W, Au, Th, U). For the remaining 10 elements (S, K, Ca, Sc, V, Mn, Fe, Zn, As, Sb) two or all three techniques gave results of similar quality. In spite of good performance relative to certified reference materials the ICPMS data for some elements were systematic low relative to corresponding data from INAA and EDXRF, presumably because the samples contained mineral matter not dissolved in the nitric acid dissolution for ICPMS.