Mercury in Russula mushrooms: Bioconcentration by Yellow-ocher Brittle Gills Russula ochroleuca

Abstract

The purpose of this study was to examine the contamination and bioconcentration potential of mercury (Hg) in Yellow-ocher Brittle Gills known also as Yellow-ocher Brittle Gill or Common Russula (Russula ochroleuca) mushroom. Matured fruiting bodies of this fungus and soil samples were collected at ten spatially distant unpolluted sites in the northern part of Poland in 2004–2008. Total Hg content of fruiting bodies and soil were determined by cold-vapour atomic absorption spectroscopy (CV–AAS). The total Hg content of the Yellow-ocher Brittle Gills varied between 0.017 and 0.43 μg/g dry weights in individual caps and between 0.011 and 0.24 μg/g dw in the stipes. The mean mercury content of the mushroom varied spatially (p < 0.001) between the sites - in caps between 0.039 ± 0.024 and 0.18 ± 0.11 μg/g dw; and in stipes between 0.027 ± 0.014 and 0.13 ± 0.06 μg/g dw. The caps usually contained Hg in greater concentrations than stipes and the mean values of cap to stipe Hg concentration quotient (Qc/s) varied from 1.3 ± 0.4 to 1.9 ± 0.04. The range of Hg concentrations in the top soil layer (0–10 cm) varied from 0.011 to 0.51 μg/g dw (mean values varied between 0.025 ± 0.010 and 0.18 ± 0.13 μg/g dw). Mean Hg bioconcentration factor (BCF) varied between 0.57 ± 0.30 and 5.6 ± 1.7 for caps and 0.50 ± 0.49 and 3.3 ± 1.8 for stipes. Yellow-ocher Brittle Gills from Trójmiejski Landscape Park contained Hg at greater concentration compared to other sites. Also presented is a review of data on Hg contents of the genus Russula (41 species, both edible and inedible to man) collected from across the world.