Mercury and its bioconcentration factors in King Bolete (Boletus edulis) Bull. Fr.

Abstract

The total mercury content for a representative number of the carpophores of King Bolete from 13 sites across Poland averaged from 1.1 ± 1.4 to 7.6 ± 3.1 μg/g dry matter in the caps (total variation between 0.02 and 14 μg/g dm), and from 0.82 ± 0.71 to 3.8 ± 1.8 μg/g dm in stalks (total variation between 0.03 and 6.7 μg/g dm). A top soil layer (0–10 cm) collected from the mushroom sampling sites showed mean mercury content at range from 0.02 ± 0.01 to 0.05 ± 0.02 μg/g dm (total variation between 0.01 and 0.08 μg/g dm). King Bolete is effective mercury accumulator in the carpophores and bioconcentration factor (BCF) of this element in the caps ranged from 41 ± 6 to 130 ± 39 (total variation between 13 and 170) and in the stalks were from 27 ± 18 to 72 ± 22 (total variation between 4.0 and 90). Based on a relatively large set of data on the total mercury concentrations obtained in this survey, and dataset available for King Bolete from various sites in Europe, it seems reasonable to state that the upper food hygienic limit for the total mercury content in this species collected from unpolluted (background) sites should not exceed 20 μg/g dm in a single cap or a carpophore, while on an average, per site or consignment, should not exceed 10 μg/g dm in the caps or the carpophores.

Keywords:

• BCF
• bioindication
• fungi
• heavy metals
• mineral composition
• mushrooms
• nutrition
• wild food

Acknowledgment

This study has been supported by the Ministry of Science and Higher Education under Grant No. DS-8205-4-0092-7.

Notes

†n = 3

*Informative value

#ng/g.

*Number of samples and number of specimens (in parentheses)

**4.1 μg/g dm in tubes

^# Summer Bolete Boletus aestivalis (B. recticulatus)

^aWithout tubes – in tubes was 6.4 μg/g dm

^bInorganic 0.79 and organic 0.51 μg/g dm (61 and 39%)

^cCH₃Hg⁺ (monomethylmercury) = 0.02 μg/g dm (0.6%)

^dCH₃Hg⁺ = 0.04 μg/g dm (0.8%) and BCF_Hg = 32

^† No information was provided if the region sampled nearby to the city of Paris was contaminated with mercury or not, while concentrations noted are record high.