Natural background levels of trace elements in wild plants: Variation and distribution in plant species

Abstract

The natural levels of trace elements in wild plants of Japan were investigated. Wild plant shoots were collected at 16 sites from central to eastern Japan. The concentrations of various trace elements, namely, Be, Cu, Zn, Mo, Cd, Sb, Cs, Ba, La, Tl, Pb, and Bi, in the 410 samples of 209 species were simultaneously analyzed by inductively coupled plasma mass spectroscopy. Geometric means were calculated with the data arranged according to plant species, and some basic statistical parameters were calculated. Distribution of all the elements except La showed significant logarithmic normal pattern. The average concentrations of Sb, Cs, Ba, La, Pb, and Bi in Pterophyta were higher than those in Anthophyta. The concentrations of Be, Cu, Ba, La, and Pb were higher in Dicotyledonopsida than in Monocotyledonopsida and the reverse was true for Mo concentrations. Cu, Cd, and Cs concentrations were higher in Sympetalidae than Archichlamiidae. Concerning plant families, Moraceae and Cyperaceae contained more Mo, Compositae, Polygonaceae, and Liliaceae more Cd, Saxifragaceae more Cs, Polygonaceae more Tl, and the families belonging to Pterophyta showed higher Cd, Sb, La, Pb, and Bi concentrations.