Trace elements in the pollen of Ambrosia artemisiifolia: what is the effect of soil concentrations?

•Concentrations of ragweed pollens: Zn>Mn>Ba≈Cr≈Cu≈Ni≈Pb>Cd≫Tl.•Mean pollen to root ratios always<1; Cu, Ni and Zn have maximum ratios>1.•Significant models of pollen concentrations for Cd, Ni and Pb, not for Cu and Zn.•All models involve positive relations between trace elements in pollens and soils.•Maximum estimate of monthly trace element inhale by humans through pollens<50ng.