Mercury content and bio-concentration potential of Slippery Jack, Suillus luteus, mushroom

Abstract

This study aimed to assess the total Hg intake due to the meals made of fruit bodies of wild-grown Slippery Jack ( Suillus luteus) fungus, which is popular and numerous species in young the common pine tree ( Pinus sylvestris) forests of the northern chemosphere with temporal climate. Total mercury content has been determined separately in 120 composite samples of 383 caps and stipes of Slippery Jack and in surface soil layer (0–10 cm; <2 mm fraction) underneath to fruit bodies. The material originated from eight spatially distant background (unpolluted) areas across of Poland and was collected in 2002–2007. Determination of mercury was by cold-vapour atomic absorption (CV-AAS) after direct sample matrix pyrolysis and further released mercury amalgamation and desorption from gold wool. Slippery Jack effectively accumulated Hg in fruit bodies. Depending on the area of mushrooms collection, the median values of Hg bio-concentration factor varied between 2.5 and 14 for caps and between 1.0 and 8.8 for stipes. For well-developed fruit bodies of Slippery Jack a majority of Hg occurs in caps, when compared to much smaller in size stipes. The means of Hg content varied between 0.095 ± 0.082 and 0.28 ± 0.07 μg/g in caps and between 0.045 ± 0.018 and 0.13 ± 0.03 μg/g dry weight in stipes. A meal consisting of 300 g caps (fresh weight) of Slippery Jack mushroom collected from unpolluted sites could constitute up to 14–40% of daily reference dose (RfD) value of mercury.