Małgorzata Drewnowska

Mercury in bay bolete (Xerocomus badius): bioconcentration by fungus and assessment of element intake by humans eating fruiting bodies

Concentrations of mercury (Hg) were determined in 221 specimens of bay bolete and in 221 samples of corresponding forest topsoil layer (0–10u2009cm) collected from 18 sites across geographically and industrially diverse regions of Poland in 2000–2008. Mercury concentrations in caps and stipes of bay bolete were strongly correlated (pu2009<u20090.0001), whereas the relationship between the Hg concentrations in soil and mushrooms varied depending on the sampling location. The bay bolete showed a lower bioconcentration potential of Hg at sites with elevated soil Hg concentrations and a higher bioconcentration at sites with lower Hg concentrations in soil. In view of Hg content, the consumption of bay boletes (caps or whole mushrooms) at the regions surveyed at least at a rate up to 2.5u2009kg per capita weekly in a mushrooming season is safe and will not result in exceeding of currently allowable Hg intake doses.

Mercury in European Blushers, Amanita rubescens, mushrooms and topsoils: Bioconcentration potential and intake assessment

Total mercury content has been determined in fruiting bodies of European Blushers and topsoils collected from 11 sites across Poland in 2006-2008. Mercury analysis was carried out using a validated analytical method and cold-vapour atomic absorption (CV-AAS). The European Blusher effectively accumulated mercury in fruiting bodies. The mean values of total mercury in caps of European Blushers from background (uncontaminated) areas were from 0.22 to 1.0 (0.067-3.2) and in stipes from 0.16 to 0.65 (0.071-2.7) μg/g dry weight. In topsoil beneath to fruiting bodies, the median Hg concentration at 10 sites in Northern Poland varied between 0.030 and 0.072 (0.0096–0.19) μg/g dw, and in one site in Southern Poland was 0.20 (0.079–0.34) μg/g dw. Data on Hg in European Blushers from different countries were reviewed. The mean concentrations of total Hg in caps of European Blushers from two “pristine” sites in northern part of Poland were ∼1.0 μg/g dw. A meal made with 300–500 g of fresh caps of European Blushers collected at such sites (assuming 90% water content in caps) can result in Hg intake of 0.0003–0.0005 mg Hg/kg bm (assuming a 60 kg bm), which is a dose equipotent to a new provisional tolerable weekly intake (PTWI) value set for inorganic Hg.

Investigation on mineral composition and accumulation by popular edible mushroom common chanterelle (Cantharellus cibarius)

In this study accumulation, content and multivariate relationship of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn in Cantharellus cibarius and topsoil collected from four places of Central and Northeastern Poland were investigated. Mercury was determined using cold vapor atomic absorption spectroscopy and other elements by inductively coupled plasma-optical emission spectroscopy. Principal Component Analysis (PCA) was used to examine the interdependences between 20 elements sequestered in fruit bodies by C. cibarius and in the soil substratum. Fruit bodies of Common Chanterelle from all places investigated can be considered as relatively abundant in essential elements such as: K, P, Mg, Na, Ca, Fe, Zn, Cu, Mn and Co. This mushroom effectively accumulates Rb, K, P, Cu, Cd, Ag, Na and Zn from the soil substratum, while Al, Ba, Cr, Fe and Pb are excluded.

Occurrence and accumulation of mercury in two species of wild grown Pleurotus mushrooms from Southeastern Nigeria.

The aim of this study was to evaluate the degree of contamination and intake rates, as well as the risk of Hg contained in two wild species of Pleurotus mushrooms--Oyster Mushroom (P. ostreatus) and King Tuber Mushroom (P. tuber-regium)--which are widely consumed in southeastern Nigeria; and to also assess their potential to accumulate Hg. The mean Hg concentrations in caps of P. ostreatus from distant sites of Ekeoba, Ntigha, and Ubakala in Abia State, were 31±11, 28±8, and 29±5 ng g(-1) dry weight, respectively; while the mean concentrations for stipes were 37±5, 36±17, and 28±6 ng g(-1) dw, in the respective communities. The caps and stipes were characterized by a mean bioconcentration factor value of ∼2, indicating that P. ostreatus is a very weak Hg accumulator and probably takes in Hg solely from the wooden substratum. Sclerotia of P. tuber-regium, purchased from five different regional markets: Ukwunwangwu (Uturu), Ekeama (Umuobiala), and Ahonta (Eluama) of Abia State; and from Abakpa market and Eke-Okigwe of Imo State; contained Hg in total range of 3.3 to 180 ng g(-1) dw. A meal consisting of 300 g of caps and stipes of P. ostreatus, or of fresh sclerotia of P. tuber-regium, would expose a consumer to <1.2, and between 0.39 and 1.2 μg Hg, respectively; and, if eaten daily for a week, would contribute less than 0.03%, and between 0.76% and 2.3% of the provisionally tolerable weekly intake (PTWI). The consumption of P. ostreatus and sclerotia of P. tuber-regium harvested from the areas investigated, therefore, poses no toxicological or health risks to the inhabitants.

Mercury in fruiting bodies of dark honey fungus (Armillaria solidipes) and beneath substratum soils collected from spatially distant areas.

BACKGROUNDnThis paper reports data on bioconcentration potential and baseline mercury concentrations of fruiting bodies of dark honey fungus (Armillaria solidipes) Peck and soil substrate layer (0-10 cm) from 12 spatially distant sites across Poland. Mercury content of caps, stipes and soil samples were determined using validated analytical procedure including cold-vapor atomic absorption spectroscopy after thermal decomposition of the sample matrix and further amalgamation and desorption of mercury from gold wool.nnnRESULTSnMean mercury concentrations ranged from 20 ± 8 to 300 ± 70 ng g(-1) dry weight (dw) in caps, from 20 ± 6 to 160 ± 40 ng g(-1) dw in stipes, and in underlying soil were from 20 ± 2 to 100 ± 130 ng g(-1) dw. The results showed that stipes mercury concentrations were 1.1- to 1.7-fold lower than those of caps. All caps and the majority of stipes were characterized by bioconcentration factor values > 1, indicating that dark honey fungus can be characterized as a moderate mercury accumulator.nnnCONCLUSIONnOccasional or relatively frequent eating of meals including caps of dark honey fungus is considered safe in view of the low total mercury content, and the mercury intake rates are below the current reference dose and provisionally tolerable weekly intake limits for this hazardous metal.

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

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.

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.

Mercury in Yellow-cracking Boletes Xerocomus subtomentosus mushrooms and soils from spatially diverse sites: Assessment of bioconcentration potential by species and human intake

This study investigated the Hg concentrations in Yellow-cracking Boletes Xerocomus subtomentosus mushrooms and beneath soils collected from the wild at twelve sites across Poland. This mushroom species has some potential to bioconcentrate Hg in the fruiting bodies, and the amount of Hg sequestered, depending on geographical location, can pose health risk to consumers. The values of Hg bioconcentration factor (BCF) varied for the sites between 0.80 ± 0.20 and 17 ± 12 in caps and 0.50 ± 0.10 and 7.9 ± 6.6 in stipes of fruiting bodies but decreased as soil Hg content increased from 72 ± 32 to 570 ± 130 ng/g dry weight. The specimens collected from minerals rich area of Złotoryja contained the highest Hg concentration, which reached 630 ± 400 in caps and 420 ± 260 ng/g dw in stipes, while the lowest observed Hg concentrations at the other sites were 72 ± 32 and 57 ± 13 ng/g, for cap and stipes respectively. Available literature data on Hg in Yellow-cracking Boletes was also up-dated.

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

This study examined the mercury concentration in the Grisette Amanita vaginata Fr. and soil below the fruiting bodies collected between 2000 and 2008 from the wild at seven distant sites across Poland. The Hg content in samples was determined by cold atomic absorption method (CV-AAS) at a wavelength of 253.7 nm. Mean Hg contents varied from 0.096 ± 0.052 to 0.48 ± 0.13 mg kg−1 dry matter (dm) in caps (range, 0.043–0.73 mg kg−1), from 0.047 ± 0.02 to 0.23 ± 0.07 mg kg−1 dm (range, 0.028–0.47 mg kg−1) in stipes, and in underlying soil were from 0.035 ± 0.018 to 0.096 ± 0.036 mg kg−1 dm (range, 0.017 to 0.16 mg kg−1). The median Qc/s values ranged from 1.2 to 2.2 (mean 1.2 ± 0.4 to 2.1 ± 0.5) indicating that Hg content in stipes was generally lower than in caps. This mushroom species has some potential to bioconcentrate Hg in the fruiting bodies, as the values of the bioconcentration factor (BCF) varied for the sites between 1.2 ± 0.6 to 11 ± 5 for caps and 0.61 ± 0.26 to 7.4 ± 3.9 for stipes. Also available literature data on Hg in A. vaginata are reviewed and discussed.

Mineral constituents in common chanterelles and soils collected from a high mountain and lowland sites in Poland

This paper reported the results of the determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (0–10 cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma — atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioconcentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set.