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

Essential Mineral Content (Fe, Mg, P, Mn, K, Ca, and Na) in Five Wild Edible Species of Lactarius Mushrooms from Southern Spain and Northern Morocco: Reference to Daily Intake

Mushroom consumption has increased in recent years due to their beneficial properties to the proper functioning of the body. Within this framework, the high potential of mushrooms as a source of essential elements has been reported. Therefore, the present study aims to determine the mineral content of seven essential metals, Fe, Mg, Mn, P, K, Ca, and Na, in twenty samples of mushrooms of the genus Lactarius collected from various locations in southern Spain and northern Morocco, by FAAS, UV-Vis spectroscopy, and ICP-OES after acid digestion. Statistics showed that K was the macronutrient found at the highest levels in all mushrooms studied. ANOVA showed that there were statistically significant differences among the species for K, P, and Na. The multivariate study suggested that there were differences between the accumulation of the elements according to the geographic location and species. Furthermore, the intake of 300 g of fresh mushrooms of each sample covers a high percentage of the RDI, but does not meet the recommended daily intake (RDI) for any of the metals studied, except for Fe. Even considering these benefits, the consumption of mushrooms should be moderated due to the presence of toxic metals, which may pose health risks.

Occurrence, distribution, and associations of essential and non-essential elements in the medicinal and edible fungus "Fuling" from southern China

In Asian countries, the sclerotia of the wild-grown fungus Pachyma hoelen ("Fuling"), have been used as food and as medicinal products for centuries. To close the knowledge gaps about the value and possible environmental impacts, the occurrence, distribution, and associations of a range of elements (Ag, Al, As, Ba, Cd, Co, Cr, Cs, Cu, Li, Mg, Mn, Ni, Pb, Rb, Sb, Sr, Tl, U, V, and Zn) were studied in the inner (core) and outer (shell) morphological parts of the sclerotia from a diverse collection in Southern China. Quality of forest and agricultural soil in terms of a geogenic element source and composition can be considered as the main factor determining the occurrence of minerals in sclerotia through the host wood, largely of Pinus yunnanensis, while the anthropogenic impact (basically at remote rural areas of cultivation) in Southern China was negligible. In general, the mean concentration of each element in the outer part was significantly higher than that in the inner part (t-test, p < 0.01), except for Ag. The concentration of a given element in the outer part tended to have a positive relationship with that in the inner part, except for Cu, Se, Ag, and Zn. The elements in different morphological parts of sclerotia present different relation patterns. Compared to the outer part, there were stronger associations of elements in the inner part, suggesting homeostatic regulation of multiple elements in the inner parts. Further study on the sclerotia, infected wood substrate, and surrounding soil from a range of wild sample collections and intentional cultivation should provide a more complex view and allow assessment of the relationship between minerals and bioactive organic compounds produced by P. hoelen.

Occurrence and Health Risk Assessment of Cadmium Accumulation in Three Tricholoma Mushroom Species Collected from Wild Habitats of Central and Coastal Croatia

This study deals with the biomonitoring of cadmium (Cd) heavy metal in the three selected Tricholoma mushroom species collected from wild habitats of central and coastal Croatia. For this, mushroom (T. columbetta: n = 38, T. portentosum: n = 35, and T. terreum: n = 34) and surface soil samples were collected from nine forest localities of Croatia and analyzed for Cd concentration using inductively coupled plasma−optical emission spectrometry (ICP−OES) through the acid digestion method. The findings revealed that Cd was present in Tricholoma spp. and surface soil. However, the maximum mean Cd concentration (mg/kg dry weight) was recorded in T. portentosum (cap: 0.98; stipe: 0.72), followed by T. columbetta (cap: 0.96; stipe: 0.73) and T. terreum (cap: 0.81; stipe: 0.63). The bioconcentration factor (BCF) value (>1) revealed that the selected Tricholoma spp. had the potential for Cd accumulation. Moreover, the principal component (PC) and hierarchical cluster (HC) analyses were used to derive the interactions and similarities between Cd levels Tricholoma spp. and sampling localities. The multivariate analysis suggested that central sampling localities had higher Cd levels as compared to coastal localities. However, the daily intake of metals (DIM < 0.426) and health risk index (HRI < 1) showed that there was no potential health risk associated with the consumption of selected Tricholoma spp. The findings of this study are helpful to understand the Cd accumulation behavior of wild edible Tricholoma spp. collected from Croatia.

Fungus–Fungus Association of Boletus griseus and Hypomyces chrysospermus and Cadmium Resistance Characteristics of Symbiotic Fungus Hypomyces chrysospermus

Fungi bioaccumulation of heavy metals is a promising approach to remediate polluted soil and water. Boletus griseus could accumulate high amounts of Cd, even in a natural habitat with low Cd contents. This study found a symbiotic association of B. griseus with a fungus. The symbiotic fungus was isolated and identified as Hypomyces chrysospermus. The isolated strain had a strong ability to tolerate Cd. The minimum inhibitory concentration of Cd of fungal growth was 200 mg·L−1. The Cd bioaccumulation capacity of the fungus reached 10.03 mg·g−1. The biomass production of the fungus was promoted by 20 mg·L−1 Cd. However, high concentrations of Cd suppressed fungal growth and significantly altered the morphology and fine texture of fungal hyphae and chlamydospores. The immobilization effects of the cell wall and acid compounds and antioxidant enzymes were employed by the fungus to alleviate the toxic effects of Cd. The results not only demonstrate a new insight into the Cd bioconcentration mechanisms of B. griseus but also provide a potential bioremediation fungus for Cd contamination.

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.

Mushroom Quality Related with Various Substrates' Bioaccumulation and Translocation of Heavy Metals

Mushrooms are popular due to the nutrition contents in the fruit bodies and are relatively easy to cultivate. Mushrooms from the white-rot fungi group can be cultivated on agricultural biomass such as sawdust, paddy straw, wheat straw, oil palm frond, oil palm empty fruit bunches, oil palm bark, corn silage, corn cobs, banana leaves, coconut husk, pineapple peel, pineapple leaves, cotton stalk, sugarcane bagasse and various other agricultural biomass. Mushrooms are exceptional decomposers that play important roles in the food web to balance the ecosystems. They can uptake various minerals, including essential and non-essential minerals provided by the substrates. However, the agricultural biomass used for mushroom cultivation is sometimes polluted by heavy metals because of the increased anthropogenic activities occurring in line with urbanisation. Due to their role in mycoremediation, the mushrooms also absorb pollutants from the substrates into their fruit bodies. This article reviews the sources of agricultural biomass for mushroom cultivation that could track how the environmental heavy metals are accumulated and translocated into mushroom fruit bodies. This review also discusses the possible health risks from prolonged uptakes of heavy metal-contaminated mushrooms to highlight the importance of early contaminants’ detection for food security.

Accumulation of Selected Metal Elements in Fruiting Bodies of Oyster Mushroom

The species Pleurotus ostreatus is a commercially, gastronomically, and biotechnologically important fungus. Its strain variability has been little researched. The study provides an evaluation of 59 oyster mushroom production strains in terms of the ability to accumulate selected metals in the cap and stipe. The fruiting bodies were grown under identical model conditions on straw substrate. Metal concentrations (ET-AAS) in dry fruiting bodies ranged in values 1.7-22.4 mg kg-1 for Al, 2.6-9.7 mg kg-1 Ba, 199-4560 mg kg-1 Ca, 1.7-12.0 mg kg-1 Cu, 12-120 mg kg-1 Fe, 16,000-49,500 mg kg-1 K, 876-2400 mg kg-1 Mg, 0.39-11.0 mg kg-1 Mn, 46-920 mg kg-1 Na and 11-920 mg kg-1 for Zn. More Cu, Fe, K, Mg, Mn, Zn accumulated in the cap, while in the stipe Ba was amassed. No significant difference was found between Al, Ca and Na between the accumulation in the cap and the stipe. Furthermore, the dependence of metal uptake from the substrate depending on the fortification of the substrate was confirmed. Statistically significant (p < 0.05) synergistic relationships were shown in pairs Al and Ba, Al and Fe, Ba and Na, Ba and Ca, Ca and Na, Cu and Fe, Fe and Mn, Fe and Zn, K and Mg, K and Mn, K and Zn, Mg and Mn, Mg and Na, Mg and Zn and Mn and Zn in the substrate without the addition of sodium selenate to the substrate. Altered relationships were observed after the application of sodium selenate to the substrate, synergism of Se and Ni, Se and Co and Se and Hg, Cu and Mn, Cu and Fe, Zn and Co, Zn and Ni, Zn and Hg, Mn and Fe, Mn and Cr, Co and Ni, Co and Hg, Ni and Hg, Pb and Cd. The findings of the study may help in the selection of production strains with hypercumulative properties for a particular metal and subsequent use in the addition of fortified fruiting bodies (e.g., with Zn). Based on the study the strains less sensitive to the accumulation of hazardous metals is possible to select for large-scale production, which is important from the perspective of food safety.

Distribution and Origin of Major, Trace and Rare Earth Elements in Wild Edible Mushrooms: Urban vs. Forest Areas

This paper investigates the composition of major, trace, and rare earth elements in 15 different species of wild edible mushrooms and the possible effect of urban pollution on elemental uptake. The collected mushrooms include different species from the green areas of the city, exposed to urban pollution, and from the forests, with limited anthropogenic influence. Through a comprehensive approach that included the analysis of 46 elements, an attempt was made to expand knowledge about element uptake by mushroom fruiting bodies. The results showed a wide variability in the composition of mushrooms, suggesting a number of factors influencing their element uptake capacity. The data obtained do not indicate significant exposure to anthropogenic influences, regardless of sampling location. While major elements’ levels appear to be influenced more by species-specific affinities, this is not true for trace elements, whose levels presumably reflect the geochemical characteristics of the sampling site. However, the risk assessment showed that consumption of excessive amounts of the mushrooms studied, both from urban areas and from forests, may have adverse health effects.

Natural radioactivity and total K content in wild-growing or cultivated edible mushrooms and soils from Galicia (NW, Spain)

The radioactive isotope, ⁴⁰K, of naturally occurring potassium (0.012%) is present in the Earth's crust in a low percentage of all potassium, leading to its presence in almost all foodstuffs. The impact of ⁴⁰K activity concentrations was assessed in wild and cultivated edible mushrooms and in growing substrates. Samples were analysed by gamma spectroscopy. In the wild mushroom species, the average activity concentration of ⁴⁰K was 1291 Bq kg^-1 dry weight (dw), approximately 140 Bq kg^-1 fresh weight (fw), with a range of average values per species from 748 in Lactarius deliciosus to 1848 Bq kg^-1 dw in Tricholoma portentosum. The cultivated species presented an average value of 1086 Bq kg^-1 dw; and the soils, compost of cultivation and wood of substrate are 876, 510 and 59.4 Bq kg^-1 dw, respectively. The total K content reached a maximum of 59,935 mg kg^-1 dw in T. portentosum. The transfer factors (TF > 1) suggested that mushrooms preferentially bioconcentrated ⁴⁰K. Cantharellus cibarius, Craterellus tubaeformis, Hydnum repandum and T. portentosum by most TF could be considered as bioindicators of ⁴⁰K. Taking into account that the annual radiation dose of ⁴⁰K due to the average consumption of mushrooms analysed (0.15 μSv/year) is very low, it can be concluded that the consumption of these mushrooms does not represent a toxicological risk for human health. Finally, according to the total K content, from the nutritional point of view, these mushrooms could be considered as a potential source of potassium for the human diet.

Mercury in Macrolepiota procera (Scop.) Singer and Its Underlying Substrate-Environmental and Health Risks Assessment

Wild-growing edible mushrooms are valuable food with a high content of proteins, fibers, antioxidants, and they are characterized by their specific taste and flavor. However, from an ecotoxicological point of view, they are a risk commodity because of their extremely high bioaccumulative capacity to accumulate the risk elements and contaminants from the environment. In the present study, we examined mercury (Hg) contamination in 230 fruiting bodies of Macrolepiota procera (Scop.) Singer and 230 soil/substrate samples, which were collected in foraging seasons 2015-2019 from 22 different locations in Slovakia. Total mercury content was determined by cold-vapor AAS analyzer AMA 254. The level of contamination and environmental risks were assessed by contamination factor (Cf), index of geoaccumulation (Igeo), and potential environmental risk index (PER). Bioaccumulation factor (BAF) was calculated for individual anatomical parts of M. procera. Mercury content in the soil/substrate samples varied between 0.02 and 0.89 mg kg-1 DW, and in mushroom samples between 0.03 and 2.83 mg kg-1 DW (stems), and between 0.04 and 6.29 mg kg-1 DW (caps). The obtained results were compared with the provisional tolerable weekly intake for Hg defined by WHO to determine a health risk resulting from regular and long-term consumption of M. procera.

Toxicity, mutagenicity and trace metal constituent of Termitomyces schimperi (Pat.) R. Heim (Lyophyllaceae) and kaolin, a recipe used traditionally in cancer management in Cote d'Ivoire

ETHNOPHARMACOLOGICAL RELEVANCE

Some local communities in Cote d'Ivoire use the mushroom Termitomyces schimperi combined with kaolin (TSK) to manage various cancers in patients. However, there is a paucity of data on toxicity, mutagenicity and trace metal constituent of TSK.

AIM OF THE STUDY

We sought to investigate the acute and sub-chronic toxicities, mutagenic potential, and trace metal constituents of TSK.

MATERIALS AND METHODS

To assess acute toxicity, single doses (1000, 3000 and 5000 mg/kg) of aqueous extract of TSK were administrated per os to Sprague Dawley (SD) rats on Day 1. The rats were then monitored for 13 consecutive days. Sub-chronic toxicity was evaluated by daily administration of 200 and 500 mg/kg of the extract per os for 90 consecutive days. SD rats used as control received distilled water. Signs of toxicity, changes in body weight and mortality were monitored. After the aforementioned monitoring processes, rats were sacrificed and blood collected for full blood count and biochemistry analysis. Animal organs were also collected for histopathological examination. The mutagenic potential of the aqueous extract of TSK (10000 μg/mL) on TA98 Salmonella typhimurium was estimated. Additionally, energy-dispersive X-ray fluorescence (ED-XRF) method was employed to determine trace metal constituents of TSK.

RESULTS

Single-dose administration of 5000 mg/kg of TSK did not cause any death in the SD rats; thus, LD50 was above 5000 mg/kg. Administration of 1000 and 3000 mg/kg of the aqueous extract of TSK did not cause any significant change in behaviour and body weight of SD rats during the 14-day monitoring period. However, the mean corpuscular volume and the mean corpuscular haemoglobin concentration increased significantly (p < 0.01) among rats administered 1000 and 3000 mg/kg of TSK. There was a significant increase (p < 0.0001) in alanine transaminase levels in rats administered 1000 and 3000 mg/kg of TSK extract compared with control. Conversely, there was a significant decrease (p=0.0122) in serum creatine level among rats administered 1000 and 3000 mg/kg of TSK extract compared with control. After 14 days, there were minimal changes with isolated organs of TSK-treated and control rats. Furthermore, 90-day treatment with extract of TSK caused no significant change in parameters assessed. TSK induced frameshift gene mutation in S. typhimurium before (p < 0.05) and after metabolic activation (p < 0.001). Elemental analysis of TSK revealed the presence of toxic (aluminium) or potentially toxic (silver, rabidium, titanium and zirconium) elements.

CONCLUSIONS

The aqueous extract of TSK showed no toxicity (acute and sub-chronic) at doses tested. These findings are consistent with the absence of heavy metals (i.e., cadmium) and potentially toxic elements (i.e., uranium) in TSK samples analysed. TSK showed some level of mutagenic potential. Further mutagenic and chronic toxicity studies on TSK are required.

Transcriptome Analysis and Expression Profiling of Molecular Responses to Cd Toxicity in Morchella spongiola

Morchella is a genus of fungi with the ability to concentrate Cd both in the fruit-body and mycelium. However, the molecular mechanisms conferring resistance to Cd stress in Morchella are unknown. Here, RNA-based transcriptomic sequencing was used to identify the genes and pathways involved in Cd tolerance in Morchella spongiola. 7444 differentially expressed genes (DEGs) were identified by cultivating M. spongiola in media containing 0.15, 0.90, or 1.50 mg/L Cd²⁺. The DEGs were divided into six sub-clusters based on their global expression profiles. GO enrichment analysis indicated that numerous DEGs were associated with catalytic activity, cell cycle control, and the ribosome. KEGG enrichment analysis showed that the main pathways under Cd stress were MAPK signaling, oxidative phosphorylation, pyruvate metabolism, and propanoate metabolism. In addition, several DEGs encoding ion transporters, enzymatic/non-enzymatic antioxidants, and transcription factors were identified. Based on these results, a preliminary gene regulatory network was firstly proposed to illustrate the molecular mechanisms of Cd detoxification in M. spongiola. These results provide valuable insights into the Cd tolerance mechanism of M. spongiola and constitute a robust foundation for further studies on detoxification mechanisms in macrofungi that could potentially lead to the development of new and improved fungal bioremediation strategies.

Source and Health Risk Assessment of Heavy Metals in Soil-Ginger System in the Jing River Basin of Shandong Province, North China

This study investigated the characteristics and sources of heavy metals in a soil-ginger system and assessed their health risks. To this end, 321 topsoil samples and eight soil samples from a soil profile, and 18 ginger samples with root-soil were collected from a ginger-planting area in the Jing River Basin. The average concentration of heavy metals in the topsoil followed the order: Cr > Zn > Pb > Ni > Cu > As > Cd > Hg. In the soil profile, at depths greater than 80 cm, the contents of Cr, Ni, and Zn tended to increase with depth, which may be related to the parent materials, whereas As and Cu contents showed little change. In contrast, Pb content decreased sharply from top to bottom, which may be attributable to external environmental and anthropogenic factors. Multivariate statistical analysis showed that Cr, Ni, Cu, Zn, and Cd contents in soil are affected by natural sources, Pb and As contents are significantly affected by human activities, and Hg content is affected by farmland irrigation. Combined results of the single pollution index (Pi), geo-accumulation index (Igeo), and potential ecological risk assessment (Ei and RI) suggest that soil in the study area is generally not polluted by heavy metals. In ginger, Zn content was the highest (2.36 mg/kg) and Hg content was the lowest (0.0015 mg/kg). Based on the bioconcentration factor, Cd and Zn have high potential for enrichment in ginger. With reference to the limit of heavy metals in tubers, Cr content in ginger exceeds the standard in the study area. Although Cr does not accumulate in ginger, Cr enrichment in soil significantly increases the risk of excessive Cr content in ginger.

Occurrence, behavior, and human exposure and health risks of potentially toxic elements in edible mushrooms with focus on Africa

Understanding the occurrence, behavior, and fate of potentially toxic elements (PTEs) in the substrate-mushroom-human nexus is critical for assessing and mitigating their human health risks. In this review, we (1) summarized the nature, sources, and biogeochemical behavior of PTEs in the substrate-mushroom systems; (2) discussed the occurrence, exposure, and human health risks of PTEs in mushrooms with emphasis on African geological hotspots such as metalliferous and highly mineralized substrates; (3) developed a 10-step conceptual framework for identifying, assessing, and mitigating the human health risks of PTEs in mushrooms, and highlight future directions. High human exposure risks potentially exist in Africa due to the following: (1) widespread consumption of mushrooms from various metalliferrous and highly mineralized substrates such as serpentines and mine waste dumps, (2) inadequate and poorly enforced environmental health and food safety regulations and policies, (3) limited environmental and human health monitoring data, and (4) potential synergistic interactions among PTEs in mushrooms and human health stressors such as a high burden of human diseases and infections. Although the human health effects of individual PTEs are well known, scientific evidence linking human health risk to PTEs in mushrooms remains weak. A framework for risk assessment and mitigation, and future research directions are recommended.

Effects of cadmium stress on physiological indexes and fruiting body nutritions of Agaricus brasiliensis

In this study, 0, 0.5, 1, 1.5, 2, 4, 6 and 8 mg·kg^-1 of cadmium were added to the cultivation materials. In order to study the effects of different concentrations of Cd stress on J1 and J77, the contents of antioxidant enzymes, proline and malondialdehyde, Cd content, agronomic traits and yield of fruiting bodies of Agaricus brasiliensis were determined, and the nutritional components such as polysaccharide, triterpene, protein, total sugar and total amino acid were determined. The results showed that the physiological indexes of strain J1 and J77 changed regularly under different concentrations of Cd stress. J1 was a high absorption and low tolerance variety, while J77 was a low absorption and high tolerance variety. Low concentration of Cd promoted the growth of strain J1, and higher concentration of Cd promoted the growth of strain J77. The contents of protein and total amino acids in the two strains changed greatly, followed by polysaccharides, which indicated that Cd stress had the greatest impact on the three nutrients, and other nutrients were not sensitive to Cd stress.

The Concentration and Probabilistic Health Risk of Potentially Toxic Elements (PTEs) in Edible Mushrooms (Wild and Cultivated) Samples Collected from Different Cities of Iran

The present study was devoted to investigate the PTE concentrations including cadmium (Cd), chromium (Cr), copper(Cu), iron (Fe), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), arsenic(As), and zinc (Zn) among six types of edible wild, 23 cultivated mushroom samples collected from Iran's market by the aid of an inductively coupled plasma-optical emission spectrometry (ICP-OES). Also, the related health risk assessment was established by the aid of the Monte Carlo simulation method (MSC). The limit of detection (LOD) and limit of quantification (LOQ) were ranged 0.001-0.048 and 0.003-0.160 ppm, respectively. The concentrations of As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn were determined in the ranges of 0.003-11. 5, 0.0008-5.89, 0.32-26.32, 9.15-110.08, 15.25-751.17, 0.16-2.24, 2.1-60.47, 1.21-24.22, 0.16-8.92, and 37.13-268.11 mg kg^-1, respectively. According to findings, highest mean concentration of Cr in both types of mushrooms (cultivated and wild) was lower than recommended level by Codex Alimentarius/Food and Agriculture Organization/World Health Organization (CODEX/FAO/WHO) while the corresponding values for Hg (0.87 mg kg^-1), As (1.39 mg kg^-1), Ni (10.08 mg kg^-1), Cu (36.65 mg kg^-1), Cr (10.44 mg kg^-1), Cd (0.589 mg kg^-1), Fe (201.04 mg kg^-1), Mn (10.30 mg kg^-1), Zn (2266.43 mg kg^-1), and Pb (3.81 mg kg^-1) were higher than related standard levels. According to the health risk assessment, no concern regarding the non-carcinogenic risk due to the ingestion of PTEs via the consumption of the edible mushrooms, except Hg in wild mushrooms for children, was noted.

Family and species as determinants modulating mineral composition of selected wild-growing mushroom species

It has been known since the 1970s that differences exist in the profile of element content in wild-growing mushroom species, although knowledge of the role of mushroom species/families as determinants in the accumulation of diverse element remains limited. The aim of this study was to determine the content of 63 mineral elements, divided into six separate groups in the fruit bodies of 17 wild-growing mushroom species. The mushrooms, growing in widely ranging types of soil composition, were collected in Poland in 2018. Lepista nuda and Paralepista gilva contained not only the highest content of essential major (531 and 14,800 mg kg^-1, respectively of Ca and P) and trace elements (425 and 66.3 mg kg^-1, respectively of Fe and B) but also a high content of trace elements with a detrimental health effect (1.39 and 7.29 mg kg^-1, respectively of Tl and Ba). A high content of several elements (Al, B, Ba, Bi, Ca, Er, Fe, Mg, Mo, P, Sc, Ti or V) in L. nuda, Lepista personata, P. gilva and/or Tricholoma equestre fruit bodies belonging to the Tricholomataceae family suggests that such species may be characterised by the most effective accumulation of selected major or trace elements. On the other hand, mushrooms belonging to the Agaricaceae family (Agaricus arvensis, Coprinus comatus and Macrolepiota procera) were characterised by significant differences in the content of all determined elements jointly, which suggests that a higher content of one or several elements is mushroom species-dependent. Graphical abstract.

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).

Trace elements and C and N isotope composition in two mushroom species from a mine-spill contaminated site

Fungi play a key role in the functioning of soil in terrestrial ecosystems, and in particular in the remediation of degraded soils. The contribution of fungi to carbon and nutrient cycles, along with their capability to mobilise soil trace elements, is well-known. However, the importance of life history strategy for these functions has not yet been thoroughly studied. This study explored the soil-fungi relationship of two wild edible fungi, the ectomycorrhizal Laccaria laccata and the saprotroph Volvopluteus gloiocephalus. Fruiting bodies and surrounding soils in a mine-spill contaminated area were analysed. Isotope analyses revealed Laccaria laccata fruiting bodies were 15N-enriched when compared to Volvopluteus gloiocephalus, likely due to the transfer of 15N-depleted compounds to their host plant. Moreover, Laccaria laccata fruiting bodies δ13C values were closer to host plant values than surrounding soil, while Volvopluteus gloiocephalus matched the δ13C composition to that of the soil. Fungal species presented high bioaccumulation and concentrations of Cd and Cu in their fruiting bodies. Human consumption of these fruiting bodies may represent a toxicological risk due to their elevated Cd concentrations.

Elemental composition of Russula cyanoxantha along an urbanization gradient in Cluj-Napoca (Romania)

How far-reaching is the influence of the urban area over the mineral composition of the Russula cyanoxantha mushroom? We studied the metal uptake behavior of this fungus relying on the soil properties. We sampled mushroom and soil from six forests according to an urbanization gradient, and two city parks in Cluj-Napoca (Romania). The elements were quantified using inductively coupled plasma - optical emission spectroscopy (ICP-OES). The concentrations of some elements differed significantly (p < 0.05) in the samples from the city (0.39 ± 0.35 mg kg^-1 for cadmium (Cd), 0.40 ± 0.19 mg kg^-1 for chromium (Cr), 69.1 ± 29.9 mg kg^-1 for iron (Fe), 10.9 ± 1.3 mg kg^-1 for manganese (Mn), 0.76 ± 0.45 mg kg^-1 for titanium (Ti) compared with the samples from the forests (3.15-14.1 mg kg^-1 Cd, < 0.18 mg kg^-1 for Cr, 22.6-34.5 mg kg^-1 for Fe, 15.9-19.1 mg kg^-1 for Mn, 0.19-0.36 mg kg^-1 for Ti). We observed a definite negative trend in the mineral accumulation potential of this fungus along the urbanization gradient. The fungus turned from a cadmium-accumulator to a cadmium-excluder. This highlights a positive environmental influence of the urbanization over the toxic metal uptake of R. cyanoxantha. The hypothesis, that the urban soil pollution would increase the metal content of the mushroom was disproved. The possible explanation might be the elevated carbonate content of the urban soil, which is known to immobilize the metals in the soil.

Toxic trace elements in dried mushrooms: Effects of cooking and gastrointestinal digestion on food safety

Mushrooms can accumulate toxic trace elements. The objectives of the present study are to evaluate levels of mercury, cadmium, lead, and arsenic in dried mushrooms, to determine the effect of cooking on the contents of these elements, and to evaluate their bioaccessibility in the mushrooms ready for consumption. The results showed that Hg levels in Amanita ponderosa, Boletus edulis, Marasmius oreades, and Tricholoma georgii, as well as Cd levels in some samples of Amanita caesarea and T. georgii, exceeded the legislated limits. Cooking significantly reduced the levels of As (26-72%), whereas the reduction in levels of Hg, Cd, and Pb was much lower. However, the bioaccessibility of As (63-81%) was higher than the values obtained for the metals (<40%). Taking the effects of cooking and gastrointestinal digestion into account gives a more realistic estimate of the risk associated with the consumption of mushrooms.

Cadmium mobility in a circular food-to-waste-to-food system and the use of a cultivated mushroom (Agaricus subrufescens) as a remediation agent

Cadmium (Cd) and its mobility and toxicity in the food chain receives considerable public and scientific attention. Levels in soil have been increasing, partly caused by mineral fertiliser use. In many areas in the EU, intake of Cd is not far from the maximum tolerable level. Now, urban and more circular approaches to food production are being promoted, in which waste materials substitute growing media and fertilizers. Can this make the situation worse, or is it, on the contrary, possible to extract Cd from the cycle using practical microbial methods? Cd concentration, availability and accumulation in materials and crops in a closed greenhouse system was investigated first. Secondly, we tested if fungal remediation was able to remove a significant amount of Cd. A sequential extraction analysis showed how anaerobic digestion and composting changed chemical Cd availability. Cd levels in the system were comparable to agricultural soils. The vegetable crops did not accumulate Cd. However, the culture of the edible mushroom Agaricus subrufescens in the greenhouse had a strong effect on Cd mobility: It extracted 80% of the Cd from the growing medium into the mushrooms, mostly at the start of fruiting. These early Cd enriched mushrooms can be treated as special waste, while the later harvest complied with EU Cd limits for foodstuffs and can potentially be consumed. Thus, growing this mushroom species in an integrated waste-to-crop system can be a cost-efficient way to remediate Cd from the food chain.

Elemental composition of selected species of mushrooms based on a chemometric evaluation

The aim of the study was to determine 16 elements by FAAS and ICP-AES in ca. 1500 samples of 22 species of mushrooms collected from different regions of Poland and the area around Umeå in Sweden. Chemometric techniques were applied to differentiate samples with respect to their geographical origin and interspecies differentiation. Samples of Cantharellus cibarius (Fr.), Boletus edulis (Bull.) and Leccinum scabrum (Bull.) Gray from Morąg, Augustów, the Zaborski Landscape Park, Tarnobrzeg and Umeå were discriminated by factor 1 and factor 2. Some species, i.e. Cantharellus cibarius, Boletus edulis, Boletus pinophilus (Pilát & Dermek), Leccinum aurantiacum (Bull.) Gray, Leccinum scabrum and Leccinum versipelle (Fr. & Hök) Snell from one region of Poland (Augustów or Morąg) were discriminated by K, Na, Mg, Ca, Fe, Zn, Cu, Mn and Cd. The results enabled an assessment of the hypothetical percentage realisation of the recommended dietary intake (RDA) for the bio-elements in question and of provisional tolerable weekly intakes (PTWI) of toxic metals from the consumption of 100 g of mushrooms. The most abundant element in all the mushroom samples was K, especially in Gomphidius glutinosus (Schaeff. ex Fr.) (Umeå - Sweden) and Cantharellus cibarius (Poland - Morąg). Lycoperdon perlatum (Pers.) from Poland and Sweden tended to accumulate the highest levels of Mg, Fe, Zn and Cu. The highest percentage of RDA was obtained for K, Mg and Cu. Based on the estimated PTWI, it can be concluded that no health hazard is associated with the consumption of these mushrooms.

Elemental distribution including toxic elements in edible and inedible wild growing mushrooms from South Africa

Macro-elements (Ca, Fe, K, Mg and Na) and trace elements including some toxic (As, Be, Cd, Co, Cu, Mn, Ni, Pb, Se and Zn) were determined in edible and inedible wild-growing mushrooms (Amanita rubescens, Auricularia polytricha, Boletus edulis, Boletus mirabilis, Clavulina cristata, Helvella crispa, Lactarius deliciosus, Suillus luteus, Termitomyces microcarpus, Termitomyces reticulatus, Termitomyces clypeatus, Termitomyces umkowaanii, Amanita foetidissima, Amanita muscaria, Amanita pantherina, Aseroe rubra, Chlorophyllum molybdites, Ganoderma lucidum, Gymnopilus junonius, Hypholoma fasciculare, Lentinus villosus, Lepista caffrorum, Pycnoporus sanguineus, Panaeolus papilionaceus, Pisolithus tinctorius, Pleurotus ostreatus, Podaxis pistillaris, Russula sardonia, Scleroderma citrinum, Scleroderma michiganense). Analyses of samples were carried out using inductively coupled plasma-optical emission spectrometry. The elemental content in both edible and inedible mushrooms, in decreasing order, was found to be K >> Na > Ca > Mg > Fe > Mn > Zn > Cu > Se > Co > Ni > Be > Pb ≥ Cd > As. Our study revealed that the accumulation of metals from the soil is independent of whether mushrooms are edible or inedible as uptake is dependent on the soil quality and its environment. Edible mushroom species studied were found to be rich in Se (145-836% towards the RDA) with B. edulis being rich in it, C. cristata in Cu, S. luteus in Fe and H. crispa in Zn, and all contained low concentrations of toxic metals making them suitable for human consumption.

Is the Yellow Knight Mushroom Edible or Not? A Systematic Review and Critical Viewpoints on the Toxicity of Tricholoma equestre

There is no scientific consensus regarding the safety of the Yellow Knight mushroom Tricholoma equestre (L.) P.Kumm. Following reports of cases of intoxication involving effects such as rhabdomyolysis, and supportive observations from in vivo experimental models, T. equestre is considered as a poisonous mushroom in some countries while in others it is still widely collected from the wild and consumed every year. In this paper, we review all the available information on T. equestre including its morphological and molecular characterization, nutritional value, levels of contaminants observed in fruiting bodies, the possibility of mistake with species that are morphologically similar, and the in vivo data on safety and cases of human intoxication. Based on available data, it is suggested that T. equestre cannot be considered as a toxic species and does not appear to exhibit any greater health threat than other mushroom species currently considered as edible. More care should be taken when reporting cases of human poisoning to fully identify T. equestre as the causative agent and to exclude a number of interfering factors. Specific guidelines for reporting future cases of poisoning with T. equestre are outlined in this paper. Any future research involving T. equestre should present the results of molecular phylogenetic analyses.

Efficient removal of cadmium from soil-washing effluents by garlic peel biosorbent

Paddy field soil contaminated by cadmium may produce cadmium-contained corns causing Itai-itai disease, and in situ washing of soil with the organic acid is a good technical choice due to its convenience and cost-effectiveness. While the bottleneck of this technique is how to recycle the huge volume of washing effluent in an efficient and economical way. Biosorption of cadmium on the garlic peel was attempted in present study and it was found quite satisfactorily effective to remove all cadmium from the real soil leaching effluent after three-time sequential adsorption. The systematical investigation on the effect of various parameters on the adsorption of cadmium on garlic peel in the existence of tartaric ligand was performed and it was found that tartrate could change Cd²⁺ into Cd(tar)⁰ species whose electrical charge state would restrain its approach to the adsorbent particles. The porous microstructure in the transversal surface of garlic peel and the abundant groups of -COOH are the main factors affecting the adsorption capability. A demonstrative flowsheet of soil remediation by chemical washing coupled with biosorption was proposed correspondingly, in which the cadmium could be recovered from the soil washing effluent, and the recovered effluent was reused for next soil washing, and recovered garlic peel was reused for cadmium adsorption from the effluents again, showing a great prospect in the remediation of paddy field soil contaminated by cadmium. Garlic peel was used to remove the cadmium from the soil washing effluent.

Interpolated mapping and investigation of environmental radioactivity levels in soils and mushrooms in the Middle Black Sea Region of Turkey

The activity concentration of natural (²³⁸U, ²³²Th, and ⁴⁰K) and artificial (¹³⁷Cs) radionuclides was determined in 50 samples (obtained from the same station) from various species of mushrooms and soil collected from the Middle Black Sea Region (Turkey). The activities of ²³⁸U, ²³²Th, ⁴⁰K, and ¹³⁷Cs were found as 84 ± 16, 45 ± 14, 570 ± 28, and 64 ± 6 Bq kg^-1 (dry weight), respectively, in the mushroom samples and as 51 ± 6, 41 ± 6, 201 ± 11, and 44 ± 4 Bq kg^-1, respectively, in the soil samples for the entire area of study. The results of all radionuclide activity measurements, except those of ²³⁸U and ²³²Th in the mushroom samples, are consistent with previous studies. In the soil samples, the mean values of ²³⁸U and ²³²Th are above the world mean, and the activity mean of ⁴⁰K is below the world mean. Finally, the activity estimation was made with both the soil and mushroom samples for unmeasured points within the study area by using the ordinary kriging method. Radiological distribution maps were generated.

Determination of mineral contents of wild Boletus edulis mushroom and its edible safety assessment

This study aimed to determine the contents of main mineral elements of wild Boletus edulis and to assess its edible safety, which may provide scientific evidence for the utilization of this species. Fourteen mineral contents (Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Na, Ni, Sr, V and Zn) in the caps and stipes of B. edulis as well as the corresponding surface soils collected from nine different geographic regions in Yunnan Province, southwest China were determined. The analyses were performed using inductively coupled plasma atomic emission spectrometer (ICP-AES) after microwave digestion. Measurement data were analyzed using variance and Pearson correlation analysis. Edible safety was evaluated according to the provisionally tolerable weekly intake (PTWI) of heavy metals recommended by United Nations Food and Agriculture Organization and World Health Organization (FAO/WHO). Mineral contents were significantly different with the variance of collection areas. B. edulis showed relative abundant contents of Ca, Fe, Mg and Na, followed by Ba, Cr, Cu, Mn and Zn, and the elements with the lower content less were Cd, Co, Ni, Sr and V. The elements accumulation differed significantly in caps and stipes. Among them, Cd and Zn were bioconcentrated (BCF > 1) while others were bioexcluded (BCF < 1). The mineral contents in B. edulis and its surface soil were positively related, indicating that the elements accumulation level was related to soil background. In addition, from the perspective of food safety, if an adult (60 kg) eats 300 g fresh B. edulis per week, the intake of Cd in most of tested mushrooms were lower than PTWI value whereas the Cd intakes in some other samples were higher than this standard. The results indicated that the main mineral contents in B. edulis were significantly different with respect to geographical distribution, and the Cd intake in a few of regions was higher than the acceptable intakes with a potential risk.

Investigation and analysis of Galerina sulciceps poisoning in a canteen

INTRODUCTION

Guizhou Province in China has an abundant resource of wild mushrooms, including numerous poisonous species which contain various toxins. The mortality rate from wild mushroom poisoning has been high in this area in recent years. Galerina sulciceps is a dangerously toxic mushroom which can be fatal if ingested.

METHODS

we report on an epidemiological investigation of G. sulciceps poisoning which occurred in Duyun City of Guizhou Province. The characteristics of this species, its toxicity, observed clinical features, laboratory data, treatment modality, and prognosis were investigated in order to provide a reference point for the prevention and treatment of this kind of mushroom poisoning.

RESULTS

Thirteen employees showed toxic symptoms after ingesting wild mushrooms the previous day in a company canteen. Clinical manifestation varied from gastroenteritis to hepatic and renal dysfunction. Most of the 13 patients presented with nausea, vomiting, abdominal pain, diarrhea, and elevated levels of biochemical indices of hepatic and renal function, during which transaminase concentration peaked within 48-72 h. At 48 hours post-ingestion, all patients had hemodialysis, in addition to supportive care for hepatic and renal injury with oral Silibinin and Shenshuaining. All acute renal injury had resolved by day 10, and liver transaminases had trended toward normal in all patients and they were discharged. At follow-up in 30 days, both liver and renal function had completely recovered in all.

CONCLUSION

This poisoning occurs as a result of unintentional consumption of G. sulciceps, which is relatively rare in mushroom poisonings. All patients recovered fully after timely diagnosis and treatment. To prevent wild mushroom poisoning, the best preventive measure is to educate the public not to gather and eat any unidentified wild mushrooms.

Pickling of chanterelle Cantharellus cibarius mushrooms highly reduce cadmium contamination

Mushrooms are considered as potential bio-remediation agents in soil polluted with heavy metals, while many species which efficiently accumulate them in flesh are edible. Question is if there is any possible culinary use of edible mushrooms with high heavy metal contents? This study aimed to investigate and discuss a fate of cadmium (Cd) in common household-treated fruitbodies of common chanterelle Cantharellus cibarius. The samples of Cantharellus cibarius Fr. were collected from five spatially distanced sites in Poland in 2011-2012. We examined from 267 to 358 fruiting bodies per collection, and in total 1565 fruiting bodies were used. Cadmium in fungal materials from all treatments and processes (mushrooms dried, deep frozen, blanched and pickled) was determined using validated methods by inductively coupled plasma mass spectrometry with dynamic reaction cell. Blanching of fresh chanterelles caused decrease of Cd by around 11 ± 7 to 36 ± 7%, while blanching of deep-frozen mushrooms by around 40 ± 6%. A rate of Cd decrease in chanterelles was similar when the fruiting bodies were blanched for 5 or 15 min and when used was potable or deionized water. Pickling of blanched chanterelles with a diluted vinegar marinade had a pronounced effect on further removal of Cd. Blanched chanterelles when pickled lost an extra 37-71% of Cd. Total leaching rate of Cd from fresh or deep-frozen fruitbodies of chanterelle when blanched and further pickled was between 77 ± 7 and 91 ± 4%. Blanching and pickling highly decreased content of Cd in C. cibarius.

Bio- and toxic elements in mushrooms from the city of Umeå and outskirts, Sweden

Edible mushrooms (Albatrellus ovinus, Boletus edulis, Clitocybe odora, Gomphidius glutinosus, Leccinum scabrum, Leccinum versipelle, Lycoperdon perlatum, Suillus bovinus, Suillus luteus, and Xerocomus subtomentosus) collected from unpolluted areas of the city of Umeå and its outskirts in the northern part of Sweden were examined for contents of toxic metallic elements (Cd, Pb, and Ag) and essential macro- and microelements (K, Na, Ca, Mg, Cu, Fe, Mn, and Zn) using a validated method and a final measurement by flame atomic absorption spectroscopy (F-AAS). The median values of the toxic metallic element concentrations (in mg kg^-1 dry biomass, db) ranged from: 0.12-3.9, 0.46-5.1, and 0.91-6.2 for Ag, Cd and Pb, respectively. For the essential metallic elements, the median values of concentrations ranged from: 24000-58000, 15-2000, 59-610, 520-1900, 2.0-97, 16-150, 15-120, and 4.3-26 mg kg^-1 db for K, Na, Ca, Mg, Cu, Zn, Fe, and Mn, respectively. The baseline concentrations of the metallic elements determined in mushrooms were mainly affected by the fungal species. The assessed probable maximal dietary intake of Cd (0.002 mg kg^-1 body mass) solely from a mushroom meal was only slightly below a revised value of the tolerable weekly intake for this element, while for Pb (0.003 mg kg^-1 body mass) it was tenfold below the provisionally tolerable weekly intake.

Analysis of some metallic elements and metalloids composition and relationships in parasol mushroom Macrolepiota procera

The aim of the study was to characterise the multi-elemental composition and associations between a group of 32 elements and 16 rare earth elements collected by mycelium from growing substrates and accumulated in fruiting bodies of Macrolepiota procera from 16 sites from the lowland areas of Poland. The elements were quantified by inductively coupled plasma quadrupole mass spectrometry using validated method. The correlation matrix obtained from a possible 48 × 16 data matrix has been used to examine if any association exits between 48 elements in mushrooms foraged from 16 sampling localizations by multivariate approach using principal component (PC) analysis. The model could explain up to 93% variability by eight factors for which an eigenvalue value was ≥1. Absolute values of the correlation coefficient were above 0.72 (significance at p < 0.05) for 43 elements. From a point of view by consumer, the absolute content of Cd, Hg, Pb in caps of M. procera collected from background (unpolluted) areas could be considered elevated while sporadic/occasional ingestion of this mushroom is considered safe. The multivariate functional analysis revealed on associated accumulation of many elements in this mushroom. M. procera seem to possess some features of a bio-indicative species for anthropogenic Pb but also for some geogenic metals.

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.

Toxic elements and bio-metals in Cantharellus mushrooms from Poland and China

Data on multi-trace element composition and content relationships have been obtained for Cantharellus cibarius, C. tubaeformis, and C. minor mushrooms from Poland and China by inductive coupled plasma-dynamic reaction cell-mass spectroscopy. There is no previous data published on As, Li, V, Tl, and U in chanterelles from Poland and on Ba, Co, Cr, Ni, Rb, and Sr in chanterelles from China. The results implied a role of the soil background geochemistry at the collection site with the occurrence of Ag, As, Ba, Cr, Cs, Li, Mn, Pb, Rb, Sr, U, and V in the fruiting bodies. Both geogenic Cd and anthropogenic Cd can contribute in load of this element in chanterelles from the Świetokrzyskie Mts. region in Poland, while geogenic source can be highly dominant in the background areas of Yunnan. An essentiality of Cu and Zn and effort by mushroom to maintain their physiological regulation could be reflected by data for Cantharellus mushrooms from both regions of the world, but its geogenic source (and possibly anthropogenic) can matter also in the region of the Świetokrzyskie Mountains in Poland. The elements Co, Ni, and Tl were at the same order of magnitude in contents in C. cibarius in Poland and Yunnan, China. C. tubaeformis differed from C. cibarius by a lower content of correlated Co, Ni, and Zn. Soil which is polymetallic and highly weathered in Yunnan can be suggested as a natural geogenic source of greater concentrations of As, Ba, Cr, Li, Pb, Sr, U, and V in the chanterelles there while lower of Mn and Rb, when related to chanterelles in Poland. A difference in Cs content between the sites can be attributed as an effect of the ¹³⁷Cs release from the Chernobyl accident, in which Poland was much more affected than Yunnan, where deposition was negligible.

Total mercury in fresh and processed tuna marketed in Galicia (NW Spain) in relation to dietary exposure

Mercury is a toxic trace metal, which can accumulate to levels threatening human and environmental health. In this study, contents of total mercury have been determined by ICP-MS spectrometry in fresh and processed tuna (110 samples) purchased from supermarkets in NW Spain. Mercury was present in all samples analyzed; however, only one sample of fresh tuna (1.070 mg kg^-1 wet weight (w.w.)) slightly exceeded the limit of the EU (1.0 mg kg^-1 w.w.). The average mercury concentration in processed tuna was lower than fresh, 0.306 mg kg^-1 w.w., and ranged from 0.080 to 0.715 mg kg^-1 w.w. Results were compared with literature data. In regard to the three types of preparation-packaging media for canned tuna, total Hg content was found in the following order: olive oil > natural > pickled sauce; the last showed significant statistical differences (p < 0.01) with the other two preparations. Between the two evaluated canned tuna species, significant statistical differences (p = 0.008) were observed and Thunnus alalunga presented a greater mean content (0.332 ± 0.114 mg kg^-1 w.w.) compared to Thunnus albacares (0.266 ± 0.171 mg kg^-1 w.w.).Taking into account the AESAN recommendation for adults and children, as well as the EU regulations and the tuna consumption by the Spanish population, the Hg levels obtained in this study pose no risk to consumer health. However, additional studies, a monitoring process, and efforts to reduce Hg concentration in tuna would be necessary, as well as considering other sources of exposure to Hg.