Bioconcentration of chromium in edible mushrooms: Influence of environmental and genetic factors

Fungal species and element type modulate the effects of environmental factors on the concentration of potentially toxic elements in mushrooms

Numerous edible mushrooms accumulate Potentially Toxic Elements (PTE), such as cadmium, mercury, and lead, within their sporocarps. This accumulation poses a potential risk of poisoning for humans and is influenced by factors such as the mushroom species, type of element, and the level of industrialization in the region. In our study, we investigated how soil and tree stand characteristics, including C/N ratio, pH, tree diversity, canopy cover, and the proportion of deciduous trees, influence PTE concentration in mushrooms. We collected edible mushrooms from 20 plots situated in the Białowieża Primeval Forest, one of Europe's best-preserved lowland forests. Plots varied in terms of tree species composition, with other factors minimized. We used ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) technique to analyze the concentration of eight PTE (Ag, As, Cd, Ni, Pb, Sb, Sr, Tl) in eight edible mushroom species (M.procera, L.perlatum, R. butyracea, R.cyanoxantha, R.heterophylla, L.vellereus, A.mellea, and Xerocomellus chrysenteron). Our research revealed that the presence of the effect of specific factors on concentration of PTE and its direction depends on mushroom species and type of PTE. The proportion of deciduous tree species and pH of the topsoil layer emerged as the most influential factors affecting PTE concentration in mushroom samples. Tree species richness in the canopy layer did not affect PTE concentration in mushrooms, except for the concentration of Pb in X. chrysenteron. We observed a consistent profile of PTE concentration in mushrooms with similar ecological roles (ectomycorrhizal, saprotrophic, parasite mushrooms) and from comparable phylogenetic affinities.

Bioactive Peptides and Other Immunomodulators of Mushroom Origin

For centuries, humans have used mushrooms as both food and pro-health supplements. Mushrooms, especially those related to the functions of the human immune system, are rich in dietary fiber, minerals, essential amino acids, and various bioactive compounds and have significant health-promoting properties. Immunoregulatory compounds in mushrooms include lectins, terpenes, terpenoids, polysaccharides, and fungal immunomodulatory proteins (FIPs). The distribution of these compounds varies from one species of mushroom to another, and their immunomodulatory activities depend on the core structures and chemical modifications in the composition of the fractions. In this review, we describe active compounds from medical mushrooms. We summarize potential mechanisms for their in vitro and in vivo activities and detail approaches used in developing and applying bioactive compounds from mushrooms. Finally, we discuss applications of fungal peptides and highlight areas that require improvement before the widespread use of those compounds as therapeutic agents and explore the status of clinical studies on the immunomodulatory activities of mushrooms and their products, as well as the prospect of clinical application of AMPs as 'drug-like' compounds with great potential for treatment of non-healing chronic wounds and multiresistant infections.

White Acqualagna truffle (Tuber magnatum Pico): Evaluation of volatile and non-volatile profiles by GC-MS, sensory analyses and elemental composition by ICP-MS

The White Truffle is the most expensive edible underground mushroom. In this study the first characterization of the Acqualagna white truffle was delivered, taking into consideration the soil of origin and the human perception. The volatile profile was identified by GC-MS and compared with the descriptors obtained by sensory analysis. The non-volatile characterization was done using elemental composition by ICP-MS analysis, elemental analysis, and spectrophotometric assays. The volatile profile consists mainly of bis(methylthio)methane (78.72%) and other minor constituents, linked to seven odorant descriptors: garlic-like, nutty-like, geosmine-like, floral, mushroom-like, pungent and green/herbal. ICP-MS revealed that truffle has a higher content of K, P, S, Ca and Mg (97% of the elements investigated) and that it assimilates the Rare Earth Elements (REE) from the soil without discriminating them. In conclusion, this project is the first step for the enhancement of local food, linked to the territory conditions in which it is produced.

Chromium contents, distribution and bioaccessibility in cultivated mushrooms from market: Health implications for human consumption

Mushrooms are consumed worldwide as they constitute a part of traditional cuisine culture in many countries. However, chromium (Cr) accumulation in mushrooms may constitute a potential pathway for its chronical exposure to humans. In this work, the Cr contents, distribution and bioaccessibility in 140 cultivated mushrooms from 14 species in 10 top-producing provinces in China were examined. Total Cr contents were 0.09-4.71 mg·kg-1 dw (mean 0.74 mg kg-1), with 59% exceeding the 0.5 mg kg-1standard. Additionally, less Cr was accumulated in the caps than stipes, with Cr ratio in caps/stipes being 0.28-2.6, averaging 0.91. Based on the Solubility Bioaccessibility Research Consortium (SBRC) assay, the mean Cr bioaccessibility in the mushrooms was 24.8% and 50.1% in the gastric phase (GP) and intestinal phase (IP). However, samples from Guizhou show the lowest Cr bioaccessibility at 12.5% in GP and 24.8% in IP. Further, a negative correlation between total Cr contents and Cr bioaccessibility suggests that Cr bioaccessibility is critical for accurate assessment of Cr exposure. In addition, drying mushrooms increased their bioaccessibility in the gastric phase. This study shows a high Cr exceeding rate of cultivated mushrooms, which may indicate a potential exposure risk, with Cr contents and bioaccessibility showing species and regional variation.

Safe Production Strategies for Soil-Covered Cultivation of Morel in Heavy Metal-Contaminated Soils

Morel is a popular edible mushroom with considerable medicinal and economic value which has garnered global popularity. However, the increasing heavy metal (HM) pollution in the soil presents a significant challenge to morels cultivation. Given the susceptibility of morels to HM accumulation, the quality and output of morels are at risk, posing a serious food safety concern that hinders the development of the morel industry. Nonetheless, research on the mechanism of HM enrichment and mitigation strategies in morel remains scarce. The morel, being cultivated in soil, shows a positive correlation between HM content in its fruiting body and the HM content in the soil. Therefore, soil remediation emerges as the most practical and effective approach to tackle HM pollution. Compared to physical and chemical remediation, bioremediation is a low-cost and eco-friendly approach that poses minimal threats to soil composition and structure. HMs easily enriched during morels cultivation were examined, including Cd, Cu, Hg, and Pb, and we assessed soil passivation technology, microbial remediation, strain screening and cultivation, and agronomic measures as potential approaches for HM pollution prevention. The current review underscores the importance of establishing a comprehensive system for preventing HM pollution in morels.

Elucidating Heavy Metals Concentration and Distribution in Wild Edible Morels and the Associated Soil at Different Altitudinal Zones of Pakistan: a Health Risk Implications Study

This study evaluates macro-nutrient (MN) and prevailing heavy metal (HM) concentrations in wild edible morels (WEM) species viz., Morchella crassipes, Morchella pulchella, and Morchella eohespera and the associated soil that were collected from different altitudinal zones (Azad Kashmir, Murree, Swat, and Skardu) of Pakistan. A special emphasis on potential health risk analysis for HM in WEM consumption was also explored. In general, MN concentration in fruiting bodies and their associated soil samples were in the following order: potassium (K) > magnesium (Mg) > calcium (Ca) > sodium (Na) and Ca > Mg > K > Na, respectively. The concentration for HM in WEM ranged between 20.0 and 78.0 mg/kg, 1.09 and 22.1 mg/kg, 2.1 and 22.1 mg/kg, 0.26 and 13.1 mg/kg, 0.43 and 9.1 mg/kg, 1.07 and 7.0 mg/kg, 1.01 and 5.4 mg/kg, and BDL and 3.1 mg/kg for zinc (Zn), copper (Cu), nickel (Ni), manganese (Mn), cobalt (Co), chromium (Cr), lead (Pb), and cadmium (Cd), respectively, and those in underlying soil samples, lowest and highest HM concentration were recorded for Zn (33.7-113.6 mg/kg), Cu (13.0-40.8 mg/kg), Ni (3.1-23.0 mg/kg), Pb (1.3-22.0 mg/kg), Co (2.9-5.6 mg/kg), Cr (2.7-11.1 mg/kg), Mn (2.0-7.1 mg/kg), and Cd (1.1 mg/kg 7.6). Although, Cd, Pb, and Zn concentrations in some of the WEM samples and Cd in the soil had exceeded the permissible limits set by different organizations. The greater accumulation/or transfer potential for Zn, Co, Ni, and Cu were recorded in WEM from their associated soil. The health risk index (HRI) for HM in all assessed samples of WEM was < 1, predicting no risk to the consuming population. Furthermore, the correlation analyses depicted that the power of hydrogen (pH), low organic matter contents, and sandy texture are likely to be responsible for HM transfer to the lower pool of soil. But the increasing concentration of HM in WEM warrants threats and suggests further monitoring and future policy plan and implementation to avoid the potential health risks via its regular consumption.

Risk assessment of mercury through dietary exposure in China

Mercury (Hg) is a widespread heavy metal causing various damages to health, while insufficient studies assessed its exposure risk across China. This study explored concentrations in food items and dietary exposure risks across China by comprehensively analyzing the researches on total Hg (THg) in eight food items and methylmercury (MeHg) in aquatic foods published between 1980 and 2021. According to the included 695 studies, the average THg concentration in all food items was 0.033 mg/kg (ranging from 0.004 to 0.185 mg/kg), with the highest concentration in edible fungi. The average daily dietary THg exposure from all foods was 12.9 μg/day. Plant-based foods accounted for 62.7% of the dietary THg exposure. Cereals and vegetables were the primary source of THg exposure. The MeHg concentration in aquatic foods was 0.08 mg/kg, and the average dietary exposure was 3.8 μg/day. Monte Carlo simulations of the dietary exposure risk assessment of THg and MeHg showed that approximately 6.4 and 7.0% of residents exceeded the health-based guidance value set by the European Food Safety Authority, with higher exposure risk in Southwest and South China. The nationwide target hazard quotient index of THg was greater than 1, suggesting that the non-carcinogenic risk of dietary exposure to THg needed further concern. In summary, this study has a comprehensive understanding of dietary Hg exposure risks across China, which provide a data basis for Hg exposure risk assessment and policy formulation.

Exposure to Essential and Toxic Elements via Consumption of Agaricaceae, Amanitaceae, Boletaceae, and Russulaceae Mushrooms from Southern Spain and Northern Morocco

The demand and interest in mushrooms, both cultivated and wild, has increased among consumers in recent years due to a better understanding of the benefits of this food. However, the ability of wild edible mushrooms to accumulate essential and toxic elements is well documented. In this study, a total of eight metallic elements and metalloids (chromium (Cr), arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), and selenium (Se)) were determined by ICP-MS in five wild edible mushroom species (Agaricus silvicola, Amanita caesarea, Boletus aereus, Boletus edulis, and Russula cyanoxantha) collected in southern Spain and northern Morocco. Overall, Zn was found to be the predominant element among the studied species, followed by Cu and Se. The multivariate analysis suggested that considerable differences exist in the uptake of the essential and toxic elements determined, linked to species-intrinsic factors. Furthermore, the highest Estimated Daily Intake of Metals (EDIM) values obtained were observed for Zn. The Health Risk Index (HRI) assessment for all the mushroom species studied showed a Hg-related cause of concern due to the frequent consumption of around 300 g of fresh mushrooms per day during the mushrooming season.

Detrimental and essential elements in fruiting bodies of wild-growing fungi Coprinus comatus, Flammulina velutipes, and Armillaria ostoyae

Edible medicinal wild-growing fungi Coprinus comatus, Flammulina velutipes, and Armillaria ostoyae were analyzed with regard to the contents of 21 elements in their fruiting bodies. The samples were collected from selected sites in South Bohemia, the Czech Republic. C. comatus concentrated Ag, Cd, Cu, Se, and Rb with bioconcentration factors of 12, 2.5, 2.3, 1.8, and 1.1, respectively. High contents (all values expressed in mg kg^-1 dry matter) of Al (260), Ca (480), Cu (61), Fe (340), Mg (1400), and Zn (86) were determined for this species. F. velutipes was characterized with markedly high contents of Ca (360), Fe (110), Mg (1200), Mn (26), and Zn (98), respectively. A considerably high content of Ag (5.6) was revealed for A. ostoyae. High contents of Ca (150), Cu (28), Fe (190), Mg (1100), Mn (30), and Zn (40) were determined in fruiting bodies of this species as well. The data concerning the detrimental elements in fruiting bodies of studied fungi indicate no considerably negative effect on human health if they are consumed as a delicacy or used in alternative medicine.

Hair mineral analysis in the population of students living in the Lower Silesia region (Poland) in 2019: Comparison with biomonitoring study in 2009 and literature data

The paper presents a comparative analysis of biomonitoring research results using hair mineral analysis today and 10 years ago. The aim of the present work was to examine the impact of individual factors, on the content of elements in human hair. The mineral analysis of 115 hair samples was carried out using ICP-OES and AAS technique. It was shown that calcium, barium, copper, mercury, magnesium, manganese and selenium content depend on gender and is higher for women. Statistically significant synergistic correlations were identified between the following pairs of elements: (Ca-Mg), (P-S), (Mo-Sb) and (Ba-Pb). The results of the present work were compared with the previous assessment in 2009 on students of the same age. The content of most of the heavy metals in hair was reduced significantly, which is a sign of the improving state of the local environment. The greatest decrease was recorded for silver (96.6%), arsenic (93.4%), mercury (45.1%), lead (67.7%), antimony (55.2%), thallium (10 times) and cobalt (93.7%). The level of the following elements increased: Ba: 27.3%, Cu: 28.5%, Ni: 22.4%, Ti: 191%, Zn: 11.0%. Changes in the content of most heavy metals in hair have been noted, as well as changes of reference ranges, which may indicate an improvement in the state of the environment in Wrocław, Lower Silesia (Poland) over the last 10 years. These results were confirmed by biomonitoring studies carried out with human hair, which was shown to be a reliable biomarker of human exposure to toxic elements.

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).

Contents and Health Risk Assessment of Elements in Three Edible Ectomycorrhizal Fungi (Boletaceae) from Polymetallic Soils in Yunnan Province, SW China

Ectomycorrhizal fungi (EcMF) can mobilize mineral elements directly from insoluble mineral sources and accumulate various metallic elements and metalloids from soils to their fruiting bodies. Mushrooms from genus Boletus and its related genus are one of the most important EcMF which are consumed worldwide as wild edible mushrooms. Yunnan province (China) is a high biodiversity of genus Boletus mushrooms but is also an area with potential elevated contents of toxic elements in soil. Total contents of As, Ag, Ba, Cd, Co, Cr, Cs, Cu, Li, Mn, Ni, Pb, Rb, Sb, Sr, Tl, U, V, and Zn in three edible EcMF species collected from five sites of Yunnan were analyzed by inductively coupled plasma mass spectrometer. The highest contents for As, Cd, and Pb were 7.8 mg kg^-1 dry weight (dw) in the caps of Butyriboletus roseoflavus, 3.4 mg kg^-1 dw in the caps of B. roseoflavus, and 6.4 mg kg^-1 dw in the stipes of Hemileccinum impolitum. Health risk assessment of As, Cd, and Pb indicated that the estimated exposure due to intakes of some mushroom samples from the sites were above the limits recommended by the Joint FAO/WHO Expert Committee on Food Additives. Since EcMF were considered as bioexclusors of Cr, higher Cr contents in the mushroom samples, compared with previous studies, indicated high geochemical background value of Cr in the sampling sites. Relatively higher V contents in mushrooms from family Boletaceae could also associate with the high V contents in Yunnan soil. Further work is needed to identify the places in Yunnan with geochemical anomalies resulting in high levels of toxic elements in EcMF.

The three-year monitoring of 18 elements in five edible mushroom species collected from an old orchard

The content of Al, As, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Li, Mg, Mn, Ni, Rb, Se, Sr, and Zn in fruiting bodies of edible mushrooms Calocybe gambosa, Entoloma clypeatum, Entoloma saepium, Xerocomellus chrysenteron, and Amanita rubescens growing in an orchard planted with fruit trees and situated close to a high-grown forest was studied during years 2016-2018. A. rubescens showed the highest potential of the element accumulation with bioconcentration factors of 48.5, 16.2, 7.80, 6.53, 1.75, and 1.68 obtained for Rb, Cd, Cu, Zn, Sr, and Mg, respectively. Both Entoloma species accumulated the elements similarly with bioconcentration factors >1.0 obtained for Rb, Cu, Cd, and Mg. Bioconcentration factors <0.05 were obtained for Al, Cr, Fe, and Pb in all studied species. The contents of beryllium (<0.1 mg/kg dry matter) were always the lowest among the studied elements. The contents of some elements of studied mushroom species significantly fluctuated over the years. Despite the fact that some studied elements (As, Be, Cd, Pb, Ni) are considerably toxic for humans, the pronounced effect on health is not expected if the studied mushroom species are consumed occasionally and do not represent the main component of the diet.

Accumulation of heavy metals by wild edible mushrooms with respect to soil substrates in the Athens metropolitan area (Greece)

Six wild edible mushroom species, Agaricus bisporus, A. bitorquis, A. gennadii, Coprinus comatus, Psathyrella candolleana and Volvopluteus gloiocephalus, were collected from the Greater Athens area (Greece), together with their soil substrates (two depth-layers) for studying bioaccumulation of heavy metals in a densely populated urban environment. Total and bioavailable Cr, Cu, Fe, Mn, Ni, Pb and Zn concentrations in soils were assessed along with their respective concentrations in mushrooms, and were evaluated in conjunction with soil properties, including K, P and Na content, CaCO₃ equivalent percentage, mechanical composition, pH and organic matter. In particular, Cu, Pb, Zn and Ni displayed a high variability in their total and bioavailable concentrations measured in the upper soil layer. Relatively high Pb and Ni contents were measured in mushrooms, while Cu, Zn, Fe and Mn concentrations varied considerably. No significant correlations were detected between total concentrations of heavy metals in soils and mushrooms, whereas bioavailable fractions for several metals were significantly correlated with their respective content in A. bisporus, C. comatus, P. candolleana and V. gloiocephalus. K, Na and P concentrations in soils were associated to the content of several metals in fruit-bodies. The effect of soil texture on metals accumulation by mushrooms was species-dependent since high correlations were found for V. gloiocephalus and C. comatus only. Interactions between metals content in fruit-bodies seem to be species-specific except for Ni vs. Fe and Mn vs. Fe, which are positively correlated in all cases. Overaccumulation of metals in fruit-bodies was established only in respect to the bioavailable fractions of Cu, Mn, Zn and Ni in soil. The levels of toxicity for Pb were exceeded in mushrooms of five species, whereas the rest of the heavy metals (with the exception of Cu) were detected at lower contents than their recommended dietary allowances or tolerable upper intake levels.

Analyses of artificial morel soil bacterial community structure and mineral element contents in ascocarp and the cultivated soil

This study explored the differences among various artificial morel cultivations as well as the factors that influence these differences, including soil bacterial community structure, yield, and mineral element contents of ascocarp and the cultivated soil. High-throughput sequencing results revealed that the dominant bacterial phyla in all the samples, including Proteobacteria, Acidobacteria, Chloroflexi, Bacteroides, and Gemmatimonadetes, were found not only in morel soils (experimental group) but also in wheat soil (control group); the highest richness and diversity in the soil bacteria were observed during the primordial differentiation stage. The M6 group exhibited the highest yield (271.8 g/m²) and had an unexpectedly high proportion of Pseudomonas (25.30%) during the primordial differentiation stage, which was 1.77∼194.62 times more than the proportion of Pseudomonas in other samples. Pseudomonas may influence the growth of morel. The mineral element contents of the different soil groups and the ascocarp were determined by electrothermal digestion and inductively coupled plasma mass spectrometry. The results revealed that morel had high enrichment effects on phosphorus (P, bioconcentration factor = 16.83), potassium (K, 2.18), boron (B, 1.47), zinc (Zn, 1.36), copper (Cu, 1.15), and selenium (Se, 2.27). P levels were the highest followed by Se and K, and the mineral element contents in ascocarp were positively correlated with the soil element contents.

Analysis of Nutritional Quality of Black Fungus Cultivated with Corn Stalks

Black fungus is a homologous fungus of medicine and food. Its nutrient content determines the health value, and the accumulation of nutrients is easily affected by the substitute materials. The aim of this study was to analyze the effect of corn stalks as a cultivation substitution material for sawdust on macronutrients, micronutrients, and functional components of black fungus. The results reported that corn stalks could significantly increase the content of ash, protein, copper, and iron in black fungus, but reduce the content of zinc, magnesium, manganese, and colloidal substances; corn stalks had less effect on melanin and polyphenols; its effect on water, total sugar, reducing sugar, crude fiber, and total flavonoids was insignificant. Therefore, the study provided a theoretical basis for the cultivation of black fungus with corn stalks.

Metal Contents, Bioaccumulation, and Health Risk Assessment in Wild Edible Boletaceae Mushrooms

Eight wild edible Boletaceae mushrooms (227 samples) and their soils were collected from 40 locations, Yunnan province, China. Four essential metals (Fe, Mg, Zn, and Cu) and 2 toxic metals (Pb and Cd) were determined. The results showed that Boletaceae mushrooms have abundance of 4 essential metals. The highest Pb mean value was 0.70 mg/kg DW, lower than legal limits, but Cd contents significantly exceeded legal limits. Generally, bioconcentration factor (BCF) indicated that Zn and Cu were easily bioaccumulated by mushrooms. However, the BCF_Cd of Boletus griseus reached to 6.40. Target hazard quotients showed Cd was the main risk metal in Boletaceae mushrooms. The metal compositional variability and the similarity of metal contents were further determined by principal component analysis. Regression model analysis indicated that Cd contents in mushrooms were positively correlated with soil Cd contents, and negatively correlated with soil pH, except for the samples of Boletus bicolor.

Lead, cadmium and mercury contents and bioaccumulation potential of wild edible saprophytic and ectomycorrhizal mushrooms, Croatia

Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trakošćan, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg ^-1 were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg^-1) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg^-1) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.

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.

Cadmium in edible mushrooms from NW Spain: Bioconcentration factors and consumer health implications

Mushrooms do not constitute a significant portion of the human diet, but the consumption of wild and cultivated mushrooms has become increasingly in recent years. Some species accumulate high levels of toxic metals, both in unpolluted and polluted areas. In this study, we examined the accumulation capacity of cadmium in edible mushrooms in relation to certain factors and their possible toxicological implications. Cadmium concentrations were determined by an ICP-MS spectrometer in 238 samples of the fruiting bodies of 28 wild and cultivated growing edible mushrooms species and the underlying soil. The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The highest mean cadmium concentration (mg/kg dry weight) was found in Agaricus macrosporus (52.9 in H and 28.3 in RFB). All mushroom species accumulated cadmium in relation to the underlying soils. There were statistically significant differences between the hymenophore and the rest of the fruiting body (p < 0.001). Cadmium concentrations were compared to data in the literature and to levels set by legislation. It was concluded that consumption of our studied mushrooms is not a toxicological risk as far as cadmium content is concerned, although the species A. macrosporus should not be consumed.

Study of heavy metal concentrations in wild edible mushrooms in Yunnan Province, China

Contamination with heavy metals in several species of edible mushrooms from the Yunnan Province in China was determined. Samples were collected from 16 locations in the Yunnan Province, and the contamination levels of Mn, Fe, Cu, Zn, As, Cd, and Pb were analyzed. The results demonstrated that the concentrations of essential elements (Mn, Fe, Cu, and Zn) in the mushrooms were at typical levels. The concentrations of potentially toxic metals (As, Pb and Cd) were higher than the national standard values of China (1.0 mg/kg for As, 0.2 mg/kg for Cd, and 2.0 mg/kg for Pb) in most cases. Bio-concentration factors suggested that it was easier for As and Cd to be accumulated in mushrooms than Pb, and a Health Risk Index assessment also suggested that As and Cd are greater risks to health than Pb. In conclusion, heavy metal pollution in wild edible mushrooms is a serious problem in the Yunnan Province. Among the toxic metals, As and Cd in the edible mushrooms in the area are the main sources of risk, as they may cause severe health problems. The local government needs to take measures in the form of concrete policies to protect the wild edible mushroom resources in the Yunnan Province.

Radiocaesium activity concentrations in macrofungi from Galicia (NW Spain): Influence of environmental and genetic factors

Radiocaesium ((137)Cs) is an artificial radionuclide that can be captured from the soil through the mycelium of fungi. However, in Spain there are few data on its presence in edible mushrooms. (137)Cs activity concentrations were determined using 54 samples of wild and cultivated mushrooms and 18 samples of soil, all of them collected in Galicia (NW Spain) during 2010. Samples were analyzed by gamma spectroscopy with a High-Purity Germanium (HPGe) detector. The average activity concentration of (137)Cs in wild mushrooms was 249.2Bqkg(-1) dry weight (dw) and about 24.9Bqkg(-1) fresh weight (fw). Genetic factors (species) influenced the uptake of (137)Cs, highlighting Hydnum repandum as the greatest accumulator of all wild species (1016.4Bqkg(-1) dw), while cultivated species showed much lower levels (1.6Bqkg(-1) fw). Accumulation was also favored by fungal mycorrhizal ecology, whose mycelium was distributed in contaminated soil horizons. The mean levels detected in soils were 14Bqkg(-1) fw. Although some species behaved as bioexclusors of radiocaesium, the transfer factors (TF) suggest that mushrooms preferentially bioaccumulate (137)Cs. No sample reached the limit of 600Bqkg(-1) fw (about 6000Bqkg(-1) dw) indicated in the European legislation. In conclusion, the consumption of mushrooms harvested from the investigated areas poses no toxicological risk to human health due to radiocaesium.

Bioconcentration factors and potential human health risks of heavy metals in cultivated Lentinus edodes in Chengdu, People's Republic of China

Lentinus edodes is one of the most popular edible mushrooms in the market. However, it contains heavy metals that are poisonous to humans even at trace concentrations. The concentrations and bioconcentration factors of five heavy metals in cultivated L. edodes in Chengdu were studied, and the potential health risks to local residents associated with the cultivated L. edodes consumption were evaluated. Total concentrations of cadmium (Cd), lead (Pb), chromium (Cr), arsenic (As), and mercury were determined in the fruiting bodies and the substrate from three agricultural areas. Fruiting bodies samples were collected at different growing times (2, 4, 6, and 8 days). The bioconcentration factors of heavy metals from the substrate to the fruiting bodies were estimated, and the potential health risks of local L. edodes were assessed. Because antioxidant enzymes can resist the creation of reactive oxygen species and defend against heavy metals, the activities of three antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) in the fruiting bodies were also determined. A gradual change in heavy metal concentrations occurred across the growing time of the fruiting bodies. Cd transferred from the substrate to the fruiting bodies in larger concentrations than did Pb, Cr, and As. However, Chengdu residents were not exposed to significant health risks associated with consumption of local L. edodes. Nevertheless, more attention should be focused on children because of their higher sensitivity to metal pollutants.

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.