Mercury in the Grisette, Amanita vaginata Fr. and soil below the fruiting bodies

Bibliometric analysis of European publications between 2001 and 2016 on concentrations of selected elements in mushrooms

This article presents a bibliometric study of 200 European publications released between 2001 and 2016, about the contamination of mushrooms by selected elements. The analysis includes figures on the type of analyte, its concentration, the species of fungi, and its country of origin. In the literature review, 492 species of mushrooms (wild-growing and cultured) found in 26 European countries and their concentration of 74 associated elements were analysed. The papers, which dealt mainly with the heavy metal (Cd, Cu, Fe, Pb, and Zn) concentrations of mushrooms, primarily came from Turkey, Poland, Spain, and the Czech Republic. More than 50% of the publications provided data about edible mushrooms. The results of the bibliometric analysis showed that over the 16 years, European research on fungal contamination by selected analytes has not lessened in popularity and is ongoing. Many of the studies underlined the need to assess the risk to human health arising from the consumption of contaminated mushrooms taken from various habitats. These results were the effect of, among other things, the strong interest in studies carried out on edible species, in which concentrations of mainly heavy metals that are dangerous to health and are marked were indicated (Cd, Pb, and Hg).

Bio-concentration potential and associations of heavy metals in Amanita muscaria (L.) Lam. from northern regions of Poland

Fruiting bodies of Amanita muscaria and topsoil beneath from six background areas in northern regions of Poland were investigated for the concentration levels of Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Rb, Sr, and Zn. In addition, the bioconcentration factors (BCF values) were studied for each of these metallic elements. Similar to studies from other basidiomycetes, A. muscaria showed species-specific affinities to some elements, resulting in their bioconcentration in mycelium and fruiting bodies. This mushroom growing in soils with different levels of the geogenic metallic elements (Ag, Al, Ba, Ca, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Rb, Sr, and Zn) showed signs of homeostatic accumulation in fruiting bodies of several of these elements, while Cd appeared to be accumulated at a rate dependent of the concentration level in the soil substrate. This species is an efficient bio-concentrator of K, Mg, Cd, Cu, Hg, Rb, and Zn and hence also contributes to the natural cycling of these metallic elements in forest ecosystems.

Mercury impact on hematopoietic stem cells is regulated by IFNγ-dependent bone marrow-resident macrophages in mice

, but not MeHg, affects HSC through regulating IFNγ-dependent BM-resident macrophages in mice. These findings reveal a previously unknown toxicity of Hg.

Cooking can decrease mercury contamination of a mushroom meal: Cantharellus cibarius and Amanita fulva

Mushrooms (Cantharellus cibarius and Amanita fulva) were blanched (parboiled) and pickled using different treatment conditions with the aim of carrying out the study into effect on removal of toxic mercury (Hg) accumulated in flesh. Blanching of fresh sliced C. cibarius caused leaching of Hg by approximately 15%, while loss of up to 35% was observed for sliced, deep-frozen fruit bodies. The rate of Hg leaching from the C. cibarius in practice was the same when blanched for 5 or 15 min irrespective of potable or deionized water used. Pickling of blanched C. cibarius with a diluted vinegar marinade had only a minor, if any, effect on removal of Hg and was without effect on blanched caps of A. fulva. Mercury was better extracted by boiling water from the fresh caps of A. fulva (56 ± 2% of the initial level in fresh caps) than from the fresh or frozen fruit bodies of C. cibarius. Total leaching rate of Hg from a pickled C. cibarius when fresh fruit bodies were processed was between 15 ± 5 and 37 ± 7% (median range 13-34%), and when deep-frozen fruit bodies were processed, it was between 37 ± 7 and 39 ± 8% (median range 34-39%). Pickling of the caps of A. fulva with diluted vinegar did not increase leaching of Hg. Blanching of mushrooms before future culinary use is a simple procedure recommended in reduction of contamination with Hg of cooked mushroom meal. Pickling had little if any effect on further removal of Hg from the initially blanched mushrooms.

Accumulation of metallic elements by Amanita muscaria from rural lowland and industrial upland regions

This study was carried out on the accumulation and occurrence of Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Rb, Sr and Zn in the mushroom Amanita muscaria and forest topsoil from two lowland sites in the Tuchola Pinewoods in the north-central region and an upland site in the Świetokrzyskie Mountains in the south-central region of Poland. Topsoil from the upland location showed Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, Na and Zn at significantly higher concentration levels (pseudo-total fraction and often also the labile or extractable fraction) than at both lowland locations, where topsoil was richer in Mg, and similar in Rb. Amanita muscaria from the upland region differed from individuals collected in the lowland sites by higher concentration levels of Cd, Cu, Hg and Mn in caps. This could be related to higher concentration levels of the metallic elements in topsoil in the upland region. On other side, A. muscaria from the upland site was poorer in Co and Fe in caps, and in Ca, Co, Fe and Sr in stipes. In spite of the differences in content of the geogenic metallic elements in topsoil between the lowland and upland locations, A. muscaria from both regions was able to regulate uptake and accumulation of Ag, Al, Ba, Ca, K, Mg, Na, Rb and Zn, which were at similar concentration levels in caps but not necessarily in stipes.

Accumulation and distribution of metallic elements and metalloids in edible Amanita fulva mushrooms

Baseline concentrations of Ag, Al, As, Ba, Ca, Cd, Co, Cu, Cr, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr, Tl, V, U and Zn were presented in Amanita fulva collected from unpolluted areas in Poland. There is no previous data published on the bio-element constituents of A. fulva. A very narrow range of values was determined by ICP-DRC-MS and ICP-AES for the trace elements Ag, Co, Cu, Cr, Ni, Rb, Sr, Tl and Zn in caps and of Ag, Co, Cu, Mn, Ni, Sr, U and Zn in stipes and also for the macro elements K, P, Na and Mg. The fruitbodies of A. fulva from the northern (Baltic Sea coastal forests) and southwestern (Lower Silesia forests) sites differed substantially in cadmium, lead and uranium, and those from the Lower Silesia region showed them in greater concentrations. This observation may imply that A. fulva under typical geochemical site conditions is able to regulate the accumulation of many of the elements mentioned in fruiting bodies.

Mercury in forest mushrooms and topsoil from the Yunnan highlands and the subalpine region of the Minya Konka summit in the Eastern Tibetan Plateau

This study aimed to investigate and discuss the occurrence and accumulation of mercury in the fruiting bodies of wild-growing fungi (Macromycetes) collected from montane forests in two regions of southwestern China with differences in soil geochemistry, climate and geographical conditions. Fungal mycelia in soils of the subalpine region of the Minya Konka (Gongga Mountain) in Sichuan and in the highlands of Yunnan efficiently accumulated mercury in fruiting bodies (mushrooms). The examined sites in Yunnan with highly mineralized red and yellow soils showed Hg contents ranging from 0.066 to 0.28 mg kg^-1 dry biomass (db) which is roughly similar to the results obtained for samples collected from sites with dark soils relatively rich in organic matter from a remote, the subalpine region of Minya Konka. Due to the remoteness of the subalpine section of Minya Konka, as well as its elevation and climate, airborne mercury from long-range transport could be deposited preferentially on the topsoil and the Hg levels determined in soil samples taken beneath the fruiting bodies were up to 0.48 mg kg^-1 dry matter. In Yunnan, with polymetallic soils (Circum-Pacific Mercuriferous Belt), Amanita mushrooms showed mercury in caps of fruiting bodies of up to 7.3 mg kg^-1 dry biomass. Geogenic Hg from the mercuriferous belt seems to be the overriding source of mercury accumulated in mushrooms foraged in the regions of Yunnan, while long-range atmospheric transport and subsequent deposition are the mercury sources for specimens foraged in the region of Minya Konka.

Heavy metal bioaccumulation by wild edible saprophytic and ectomycorrhizal mushrooms

Heavy metals cause serious problems in the environment, and they can be accumulated in organisms, especially in the higher fungi. The concentration of Ni, Cr, Pb, Cd, and Hg in 10 species of edible mushrooms in Medvednica Nature Park, Croatia was therefore determined. In addition, the similarity between the studied species was determined by cluster analysis based on concentrations of the aforementioned metals in the fruiting bodies. The contents of nickel, chromium, lead, cadmium, and mercury in the fruiting bodies of mushrooms were obtained by X-ray fluorescence spectrometry. The highest concentrations of Ni (3.62 mg kg(-1)), Cr (3.01 mg kg(-1)), and Cd (2.67 mg kg(-1)) were determined in Agaricus campestris. The highest concentration of Pb (1.67 mg kg(-1)) was determined in Macrolepiota procera, and the highest concentration of Hg (2.39 mg kg(-1)) was determined in Boletus edulis. The concentration of all heavy metals significantly differed (p < 0.001) between examined saprophytic and ectomycorrhizal mushrooms. Considering anatomical part of the fruiting body (cap-stipe), a considerably higher concentration of the analyzed elements was found in the cap for all mushroom species. According to calculated bioconcentration factors, all the examined species were found to be bioexclusors of Ni, Cr, and Pb and bioaccumulators of Cd and Hg. Cluster analysis performed on the basis of the accumulation of the studied metals revealed great phenotypic similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation.

Evaluation of vulnerability of Suillus variegatus and Suillus granulatus mushrooms to sequester mercury in fruiting bodies

This work determined the mercury (Hg) contents and bioconcentration potential of two Suillus mushrooms, and the probable dietary intake of this element from a mushroom meal. The determination of total Hg content of fungal and soil samples was performed using cold-vapour atomic absorption spectroscopy by a direct sample thermal decomposition coupled with gold wool trap of Hg and its further desorption and quantitative measurement at a wavelength of 253.7 nm. The median values of Hg contents (mg kg(-1) dry biomass) in 213 specimens of S. variegatus from 12 background areas varied widely from 0.087 to 0.51 for caps and from 0.041 to 0.24 for stipes. In 52 specimens of S. granulatus, the Hg contents ranged from 0.30 to 0.41 for caps and from 0.058 to 0.14 for stipes. Both species could be classified as moderate accumulators of Hg and the median bioconcentration factor values ranged from 7.0 to 14 (caps) and 2.1 to 13 (stipes) for S. variegatus and 9.5 (caps) and 1.3 (stipes) for S. granulatus. The estimated intake rates of Hg with the consumption of 300-g caps were from 0.0026 to 0.015 per capita or from 0.000037 to 0.00022 mg kg(-1) body mass and this do not indicate any cause for concern associated with eating a meal once or more in a week during the mushrooming season.

Mercury bioaccumulation by Suillus bovinus mushroom and probable dietary intake with the mushroom meal

This paper reports the results of the study of the efficiency of accumulation and distribution of mercury (Hg) in the fruiting bodies of fungus Suillus bovinus and the probable dietary intake of Hg and the potential health risk. Fungal fruiting bodies and soil materials were collected from 13 background areas in the northern part of Poland between 1993 and 2013. Mercury in the caps of fruiting bodies varied from 0.10 ± 0.06 to 0.79 ± 0.40 mg kg(-1) dry biomass and in the stipes from 0.083 ± 0.028 to 0.51 ± 0.22 mg kg(-1) dry biomass. The mean values of cap to stipe Hg content quotient varied from 1.3 ± 0.2 to 2.6 ± 0.6. The Hg content in the upper 0-10 cm layer of soil substrate varied from 0.015 ± 0.004 to 0.031 ± 0.019 mg kg(-1) dry biomass. S. bovinus could be considered as an efficient accumulator of Hg, at least from low level polluted soils, and the values of Hg bioconcentration factor (BCF) varied from 6.4 ± 2.2 to 45 ± 20 for caps and from 3.8 ± 1.4 to 29 ± 11 for stipes. A conventional meal (300 g) portion of S. bovinus foraged from background areas provides Hg dose far below the provisionally tolerable weekly intake or recommended reference dose set for this element by authorities. An examination of published data on Hg in fruiting bodies of fungi genus Suillus showed low contamination of specimens foraged from background areas. Also reviewed are published data on Hg in fungi genus Suillus collected worldwide.

Mercury bio-extraction by fungus Coprinus comatus: a possible bioindicator and mycoremediator of polluted soils?

The Shaggy Ink Cap (Coprinus comatus), which is a common in wild in northern hemisphere was examined in field for potential to be used as possible bio-extractor of Hg from polluted grounds but also as possible bioindicator of urban soils (roadside, barren lands, lawns) pollution with Hg. The contents of Hg in caps and stipes of C. comatus from the grounds examined in this study correlated positively with the levels of soil contamination. Analysis of sets of data available worldwide on Hg in C. comatus and soils beneath-fruiting bodies showed on a positive correlation between degree of soil and mushroom contamination. Hence, C. comatus could be considered as a sensitive species and with bioindication and bioremediation potency for soils polluted with Hg in further studies. Young-fruiting bodies of C. comatus are edible and considered excellent if consumed soon after pick-up. Eating them when foraged from the urban places can provide to a consumer Hg at relatively high dose, while unresolved question is absorption rate of Hg compounds contained in ingested mushroom meal.

Translocation of mercury from substrate to fruit bodies of Panellus stipticus, Psilocybe cubensis, Schizophyllum commune and Stropharia rugosoannulata on oat flakes

The cultivation and fructification of 15 saprotrophic and wood-rotting fungal strains were tested on three various semi-natural medium. The formation of fruit bodies was observed for Panellus stipticus, Psilocybe cubensis, Schizophyllum commune and Stropharia rugosoannulata in the frame of 1-2 months. Mercury translocation from the substrate to the fruit bodies was then followed in oat flakes medium. Translocation was followed for treatments of 0, 1.25, 2.5, 5, 10 and 20ppm Hg in the substrate. All four fungi formed fruit bodies in almost all replicates. The fruit body yield varied from 0.5 to 15.3g dry weight. The highest bioconcentration factor (BCF) of 2.99 was found for P. cubensis at 1.25ppm Hg. The BCF decreased with increasing Hg concentration in the substrate: 2.49, 0, 2.38, 1.71 and 1.82 for P. stipticus; 3.00, 2.78, 2.48, 1.81 and 2.15 for P. cubensis; 2.47, 1.81, 1.78, 1.07 and 0.96 for S. commune; and 1.96, 1.84, 1.21, 1.71 and 0.96 for S. rugosoannulata. The Hg contents in the fruit bodies reflected the Hg contents in the substrate; the highest contents in the fruit bodies were found in P. cubensis (43.08±7.36ppm Hg) and P. stipticus (36.42±3.39ppm).

Accumulation and distribution of mercury in fruiting bodies by fungus Suillus luteus foraged in Poland, Belarus and Sweden

Presented in this paper is result of the study of the bioconcentration potential of mercury (Hg) by Suillus luteus mushroom collected from regions within Central, Eastern, and Northern regions of Europe. As determined by cold-vapor atomic absorption spectroscopy, the Hg content varied from 0.13 ± 0.05 to 0.33 ± 0.13 mg kg(-1) dry matter for caps and from 0.038 ± 0.014 to 0.095 ± 0.038 mg kg(-1) dry matter in stems. The Hg content of the soil substratum (0-10 cm layer) underneath the fruiting bodies showed generally low Hg concentrations that varied widely ranging from 0.0030 to 0.15 mg kg(-1) dry matter with mean values varying from 0.0078 ± 0.0035 to 0.053 ± 0.025 mg kg(-1) dry matter, which is below typical content in the Earth crust. The caps were observed to be on the richer in Hg than the stems at ratio between 1.8 ± 0.4 and 5.3 ± 2.6. The S. luteus mushroom showed moderate ability to accumulate Hg with bioconcentration factor (BCF) values ranging from 3.6 ± 1.3 to 42 ± 18. The consumption of fresh S. luteus mushroom in quantities up to 300 g week(-1) (assuming no Hg ingestion from other foods) from background areas in the Central, Eastern, and Northern part of Europe will not result in the intake of Hg exceeds the provisional weekly tolerance limit (PTWI) of 0.004 mg kg(-1) body mass.

Mercury in Orange Birch Bolete Leccinum versipelle and soil substratum: bioconcentration by mushroom and probable dietary intake by consumers

The aim of this study was to examine the contamination, accumulation, and distribution of mercury in fruiting bodies by Leccinum versipelle fungus collected from distant sites across Poland. Mercury was determined using validated method by cold-vapor atomic absorption spectroscopy after direct sample matrix combustion. A large set of data gained using 371 fruiting bodies and 204 soil samples revealed the susceptibility of L. versipelle to Hg contamination and permitted the estimation of probable intake of Hg contaminant by consumers foraging for this species. The range of median values of Hg determined in caps of L. versipelle was from 0.20 to 2.0 mg kg(-1) dry biomass, and the median for 19 localities was 0.65 mg kg(-1) dry biomass. The values of the Hg bioconcentration factor (BCF) determined for L. versipelle correlated negatively with Hg contents. Mercury in topsoil beneath L. versipelle ranged from 0.019 to 0.041 mg kg(-1) dry matter for less-contaminated locations (BCF of 17 to 65 for caps) and from 0.076 to 0.39 mg kg(-1) dry matter for more contaminated locations (BCF of 1.9 to 22). Fruiting bodies of L. versipelle collected in some regions of Poland if consumed in amount of 300 g in one meal in a week could provide Hg doses above the provisionally tolerable weekly intake (PTWI) value of 0.004 mg Hg kg(-1) body mass, while regular consumptions for most of the locations were below the limit even with more frequent consumption. Also summarized are available data on Hg for three species of fungi of genus Leccinum foraged in Europe.

Evaluation of the mercury contamination in mushrooms of genus Leccinum from two different regions of the world: Accumulation, distribution and probable dietary intake

This study focused on investigation of the accumulation and distribution of mercury (Hg) in mushrooms of the genus Leccinum that emerged on soils of totally different geochemical bedrock composition. Hg in 6 species from geographically diverse regions of the mercuriferous belt areas in Yunnan of SW China, and 8 species from the non-mercuriferous regions of Poland in Europe was measured. Also assessed was the probable dietary intake of Hg from consumption of Leccinum spp., which are traditional organic food items in SW China and Poland. The results showed that L. chromapes, L. extremiorientale, L. griseum and L. rugosicepes are good accumulators of Hg and the sequestered Hg in caps were up to 4.8, 3.5, 3.6 and 4.7 mg Hg kg(-1) dry matter respectively. Leccinum mushrooms from Poland also efficiently accumulated Hg with their average Hg content being an order of magnitude lower due to low concentrations of Hg in forest topsoil of Poland compared to the elevated contents in Yunnan. Consumption of Leccinum mushrooms with elevated Hg contents in Yunnan at rates of up to 300 g fresh product per week during the foraging season would not result in Hg intake that exceeds the provisional weekly tolerance limit of 0.004 mg kg(-1) body mass, assuming no Hg ingestion from other foods.

Distribution of mercury in Amanita fulva (Schaeff.) Secr. mushrooms: Accumulation, loss in cooking and dietary intake

Representative individual specimens and pooled samples of carpophores of edible wild-grown fungus Amanita fulva (Schaeff.) Secr. and forest topsoil layer (0-10 cm) beneath the carpophores were collected from 15 spatially distant places in Poland and examined for total Hg. The median values of Hg in soils for most of the sites were below 0.05 mgkg(-1) dry matter. The ability of fungus A. fulva to bioconcentrate Hg was low (BCF, bioconcentration factor values of 1.2-3.6 for caps and 0.66-1.7 for stipes) at five sites that showed Hg in soils ranging from 0.066 to 0.21 mgkg(-1) dry matter, while much higher bioconcentration (BCF of 11-25 for caps and 7.0-12 for stipes) were observed for less contaminated soils with Hg contents of 0.018-0.054mgkg(-1) dry matter. Differences were also observed in Hg contamination of A. fulva from spatially and distantly distributed sites, and the median values (mgkg(-1) dry matter) ranged from 0.13 to 0.67 for caps and from 0.065 to 0.34 for stipes, while 0.63mgkg(-1) dry matter was observed in a set of whole fruiting bodies. Boiling of fresh A. fulva for 10min reduced the Hg content by 10%. A meal of A. fulva containing 0.065mgkg(-1) of Hg in the fresh mushroom product will not result in exceeding the reference dose set for inorganic Hg and for majority of the sites assessed (>90%) intake was substantially lower than the reference dose or the provisional tolerable weekly intake of inorganic Hg.

Human exposure to heavy metals and possible public health risks via consumption of wild edible mushrooms from Slovak Paradise National Park, Slovakia

The contamination level of 92 samples (12 species) of wild edible mushrooms and underlying substrates with heavy metals (Cd, Cu, Hg, Pb and Zn) in the Slovak Paradise National Park that borders with a region of historical mining and processing of polymetallic ores, were determined. The collected samples were analyzed using of atomic absorption spectrophotometry. The metals were determined separately in hymenophore (H) and rest of fruit bodies (RFB). Bioaccumulation factor as well as ratio of metal content in H and RFB were calculated. Cadmium and lead contents in hymenophore exceeded statutory limits of the EU (Cd: 0.5 mg/kg dry weight (dw), Pb: 1.0 mg/kg dw) for edible mushrooms in 96% and 83% of the samples, respectively. The risk from the consumption of the collected mushroom species was calculated based on the provisionally tolerable weekly intake (PTWI) values, and the highest health risk arising with consumption of particularly Macrolepiota procera, Marasmius oreades and Russula vesca from the observed area was demonstrated. It was shown that average weekly consumption of tested mushrooms species results the threat of exceeding of PTWI limits in the case of cadmium values (by 164%, 86% and 4% of PTWI for M. oreades, R. vesca and R. puellaris, respectively) and of mercury (by 96% of PTWI for M. procera) but not lead.

Mercury contamination of fungi genus Xerocomus in the Yunnan province in China and the region of Europe

This article presents the results of the study on accumulation, distribution, contamination and probable dietary intake of total mercury (THg) in fruiting bodies of several species of Fungi genus Xerocomus, which emerged in the circum-Pacific mercuriferous belt region in southwestern China in Yunnan and beyond of the mercuriferous belts in the region of Europe. The mushrooms X. puniceus (Boletus amygdalinus), X. spadiceus (Boletus ferrugineus) and X. versicolor (X. rubellus) were from the Yunnan land, and X. badius (Boletus badius) was from the region of Europe in Belarus and X. badius, X. chrysenteron, X. ferrugineus, X. versicolor (X. rubellus) and X. subtomentosus from Poland. The THg in the fungal and soil materials was determined using validated method by cold-vapour atomic absorption spectroscopy. Estimated was also probable dietary intake and health risk from THg in Xerocomus spp. examined by consumers. The data showed that THg content of Xerocomus spp. emerged in the European localizations in Poland and Belarus is at an order of magnitude lower level than determined in samples from the Yunnan Province. A reason for an elevated content of THg in mushrooms from Yunnan can be related to abundance of Hg in the geochemical background of soils there. The assessed doses showed that a single meal composed of 300 g of fresh fruiting bodies of X. spadiceus from the Wuding localization in Yunnan in China if consumed once a week will provide THg at dose close to the provisional tolerable weekly intake (PTWI) value set for THg, while doses will be lower for all other localizations in Yunnan and Europe. In the Wuding localization in Yunnan a frequent consumption of X. spadiceus in volume exceeding 300 g of fresh fruiting bodies per week will provide THg at a dose exceeding the value of PTWI.

Distribution of mercury in Gypsy Cortinarius caperatus mushrooms from several populations: an efficient accumulator species and estimated intake of element

Mushroom Cortinarius caperatus is one of the several edible wild-grown species that are widely collected by fanciers. For specimens collected from 20 spatially and distantly distributed sites in Poland the median values of Hg contents of caps ranged from 0.81 to 2.4mgkg(-1) dry matter and in stipes they were 2.5-fold lower. C. caperatus efficiently accumulates Hg and the median values of the bioconcentration factor for caps range from 120 to 18 and for stipes from 47 to 7.3. This mushroom even when collected at background (uncontaminated) forested areas could be a source of elevated intake of Hg. The irregular consumption of the caps or whole fruiting bodies is not considered to pose a risk. Frequent eating of C. caperatus during the fruiting season by fanciers should be avoided because of possible health risk from Hg. Available data on Hg contents of C. caperatus from several places in Europe are also summarized.