Rare Earth Elements in Boletus edulis (King Bolete) Mushrooms from Lowland and Montane Areas in Poland

Mining/exploitation and commercial applications of the rare-earth elements (REEs: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in the past 3 decades have raised concerns about their emissions to the environment, possible accumulation in food webs, and occupational/environmental health effects. The occurrence and distribution of REEs Y and Sc in the fruitbodies of Boletus edulis collected from geographically diverse regions in Poland were studied in 14 composite samples that were derived from 261 whole fruiting bodies. Individual REE median concentrations ranged from 0.4–95 µg kg(−1) dry weight (dw). The summed REE concentrations varied widely, with a median value of 310 µg kg(−1) dw and a range of 87 to 758 µg kg(−1). The Sc and Y median concentrations (dw) were 35 and 42 µg kg(−1), respectively. Ce, La, and Nd, with median values of 95, 51, and 32 µg kg(−1), respectively, showed the highest occurrence. B. edulis collected from a forested area formerly used as a military shooting range—possibly a historically contaminated site—had an elevated summed REE content of 1796 µg kg(−1). REE concentrations were generally low in Polish King Bolete. Dietary intake from a mushroom meal was negligible, posing no health risk to consumers.