Mushrooms · Wild culinary mushroom
Bay bolete
Imleria badia · also called Bay boletus, Boletus badius, Xerocomus badius
Bay bolete is a wild edible mushroom, eaten fresh or dried in Central Europe. We found no human trial showing a health benefit from eating it. Its big research topic is pollution: it is one of the strongest mushrooms at taking up radioactive caesium from forest soil, and it can carry cadmium and arsenic, depending on where it grew. Never eat a wild mushroom unless an expert has identified it in person.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Bay bolete
Bay bolete is a wild edible mushroom collected in European forests. Most research on it is about pollution rather than health: it is among the strongest mushrooms at taking up radioactive caesium from old fallout, and it can carry cadmium and arsenic depending on where it grew. We found no human health trial. The practical cautions are location, identification by an expert, and allergy.
Radioactive caesium: why bay bolete is a famous example
After the 1986 Chernobyl accident, caesium-137 settled in European forest soil, and mushrooms that live on tree roots take it up. Bay bolete is one of the strongest at this. In a Czech survey of 25 species sampled in 2023 it had the highest level, up to 7,842 Bq per kg dry mass. No sample passed the 1,250 Bq per kg fresh-mass limit the abstract quotes, but two passed the 600 Bq per kg fresh-mass import limit. The authors estimate the yearly dose for an adult is well below 1 mSv.
In north-eastern Poland, 31 bay bolete samples had a median of 61.9 Bq per kg fresh mass and none passed the limit; levels were roughly eight times lower than in earlier Polish studies. Near a Czech hot spot, caps held up to 11.8 kBq per kg, with an estimated yearly dose of 0.102 mSv against 0.004 at a low-exposure area. In a heavily contaminated Ukrainian reserve it reached 2,680 kBq per kg dry mass, with an estimated 8.71 mSv a year in the authors' scenario, and the authors call eating wild mushrooms there still dangerous. Porcini was lower at the same reserve.
Why it holds caesium
Lab chemistry shows a mushroom pigment called norbadione A binds caesium ions strongly, and the authors assume it is involved in how mushrooms accumulate caesium-137. This is a proposed explanation from test-tube work, not proof, and the abstracts we read do not name the species.
What it is
Bay bolete is a fungus, Imleria badia, in the family Boletaceae. GBIF lists the name as accepted and lists Xerocomus badius and Boletus badius as older names, so you may meet any of the three in papers and recipes. It lives on tree roots, so it is collected wild. The part eaten is the mushroom itself, the cap and stalk. It is a different species from porcini; see our porcini page.
Food use and traditional use
A 2021 Czech paper calls it one of the most popular edible mushrooms in the Czech Republic. It is sold fresh and dried. We found no traditional medicine use in the sources we read, so none is claimed.
What the research shows on benefits
A 2025 Polish study compared three boletes and found bay bolete rich in beta-glucan (about 34 g per 100 g dry weight), vitamin C and citric acid. It also gave the strongest result of the three in one antioxidant test-tube assay. Test-tube antioxidant results do not show a benefit in people. We found no human trial of bay bolete for any health outcome; our search was not exhaustive.
Cadmium, arsenic and other metals
Metals vary hugely by place. Cadmium in Czech bay bolete ran from 0.07 to 23 mg per kg across six locations, with the highest at one granite location. In north-western Poland the mean was 0.43 mg per kg, lower than porcini (2.74) in the same study. Mercury was low. Arsenic was very high in some polluted Polish areas and in two commercial samples, and in a 2026 survey of dried mushrooms one bay bolete sample held 369 mg per kg, far above the authors' safety limit. That is one outlier, not a typical result, but it shows why the seller and origin matter. Organic-certified products had lower mercury and arsenic in that survey.
Legal and regulatory status
The caesium limits quoted above (1,250 Bq per kg fresh mass for food, 600 for imports) are taken from a paper's abstract; we did not open the EU regulations. We did not read EFSA, FDA or national cadmium and arsenic limits, so none is stated. A 2021 study says EU rules set no maximum content of elements for dried wild mushrooms. Rules differ by country and change.
At a glance
Traditional uses history, not proof
- Eaten as a popular wild mushroom, fresh or dried, in the Czech Republic and Poland (papers from 2021 and 2025).
- No traditional medicine use was confirmed in the sources we read.
Studied for research
- Nutrition as a food (beta-glucan, vitamin C, citric acid), insufficient evidence of any health effect
- Antioxidant activity in the test tube, insufficient (lab only; no people studied)
Main compounds
- Beta-glucan, alpha-glucan and chitin, the fibres in the mushroom's cell walls
- Ascorbic acid (vitamin C) and citric acid
- Norbadione A, a pigment that binds caesium in lab chemistry
- Also cadmium, arsenic and radioactive caesium-137 taken up from the soil
Common forms
- Fresh, cooked mushroom
- Dried mushroom, soaked before use
- Powder, extract or capsule (not assessed in the sources we read)
Research links: Czech caesium-137 survey, 25 species (abstract) · Radiocaesium in mushrooms from north-eastern Poland (abstract) · Chernobyl-area Ukrainian mushrooms (abstract) · Bay bolete and 34 elements, Czech locations (abstract) · Three boletes: compounds, antioxidants, metals (abstract) · Penn State Extension: Preparing and preserving mushrooms · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Imleria badia
- Naming authority
- (Fr.) Vizzini (GBIF)
- Synonyms
- Xerocomus badius (Fr.) Kuhner (GBIF synonym); Boletus badius (Fr.) Fr. (GBIF heterotypic synonym)
- Common names
- Bay bolete (English); Bay boletus (English); Maronen-Röhrling (German); Podgrzybek brunatny (Polish)
- Family or group
- Boletaceae (a fungus family; boletes), not a plant
- Classification
- Fungi > Basidiomycota > Agaricomycetes > Boletales > Boletaceae > Imleria > Imleria badia
- Native range
- Not checked as a range. The studies read sampled the Czech Republic, Poland and Ukraine.
- Habitat
- A 2026 Czech abstract groups Imleria badia with the mycorrhizal Boletales (fungi that live on tree roots), a Polish table lists it as mycorrhizal, and the Ukrainian abstract calls it a symbiotroph. The Czech 2025 study sampled forests on granite, amphibolite and peridotite.
- What it looks like
- Fruiting body: Not described here. Identification of wild mushrooms must be done in person by an expert, so no field description is given.
- Cultivation
- Wild-collected in all sources read; no cultivation source was read.
- Harvest and processing
- Sold fresh or dried and soaked; drying concentrates caesium and metals per gram (see Safety). Details not checked.
- Look-alikes and adulterants
- Name: Bitter bolete (Tylopilus felleus); Note: Listed as inedible in the Missouri Department of Conservation page and in a 2022 Polish study. The Missouri page says it resembles the king bolete, not the bay bolete. No source we read says the two are confused.; Name: Other boletes; Note: A 2026 report describes poisonings from Neoboletus boletes in China. No source we read names poisonous look-alikes of the bay bolete.
- Sustainability and conservation
- Not checked.
Traditional use and history history, not clinical proof
| Tradition or era | Documented use | Source |
|---|---|---|
| Food use | A 2021 Czech paper calls Xerocomus badius one of the most popular edible mushrooms in the Czech Republic, and a 2025 Polish paper says wild-mushroom eating in Central Europe has risen in recent years. No traditional medicine history source was read, so none is stated. | p34947901 |
Traditional use shows how it was used. It does not show that it works or is safe today.
What is inside, and how it may work
What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.
Main compounds
| Compound | Family | Where it is concentrated | Activity studied | Level of evidence |
|---|---|---|---|---|
| Norbadione A PubChem 54679293 | pigment (pulvinic-acid type) | Fruiting body (per the lab papers; the abstracts do not name the species) Not given in the abstracts. | Binds caesium ions in test-tube chemistry; assumed by the authors to be involved in caesium-137 accumulation. 5 8 14 | Laboratory research |
| Beta-glucan, alpha-glucan and chitin | cell-wall polysaccharides | Fruiting body Mean beta-glucan 34.0 g, alpha-glucan 3.31 g and chitin 22.2 g per 100 g dry weight (Sotek 2025). | Structural; no bay bolete health effect shown. 17 | Compositional analysis |
| Ascorbic acid and citric acid | organic acids | Fruiting body Ascorbic acid 43.35 mg and citric acid 128.34 mg per 100 g dry weight (means, Sotek 2025). | Linked by the authors to the strongest DPPH radical-scavenging result in the test tube. 17 | Laboratory research |
| Cadmium (contaminant) | toxic metal | Upper parts (caps) more than stalks 0.07 to 23 mg per kg across Czech locations; mean 0.43 mg per kg in north-western Poland. | Contaminant taken up from soil and air deposits. 1 17 | Compositional analysis |
| Caesium-137 (contaminant) | radionuclide | Caps higher than stipes in the Czech hot-spot study Median 61.9 Bq per kg fresh mass in north-eastern Poland; up to 7,842 Bq per kg dry mass in a Czech survey; up to 2,680 kBq per kg dry mass in a Ukrainian reserve. | Contaminant from old fallout. 11 20 6 7 | Compositional analysis |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Caesium uptake (norbadione A as a possible binder) | not applicable | Test-tube chemistry shows norbadione A forms strong complexes with caesium ions. The authors assume it is involved in caesium accumulation; the abstracts do not show this in living mushrooms. 5 8 | Laboratory research |
| Antioxidant assays | not specified | Extract antioxidant scores tracked phenolic acids and small reducing acids in test-tube assays. This is not a finding in people. 17 | Laboratory research |
Absorption, metabolism and elimination
- Absorption
- Not found for bay bolete.
- Distribution
- Not found.
- Metabolism
- Not found.
- Elimination
- Not found.
- Bioavailability
- Not established.
Isolated compounds versus whole extracts
Bay bolete is eaten as a whole food, fresh or dried. Dried, ground samples were used in the lab study. No bay bolete capsule, powder or extract product was assessed in the sources read.
Nutritional composition
The 2025 Polish study gives beta-glucan, ascorbic acid and citric acid values per 100 g dry weight. USDA has no bay bolete entry in the files we hold, so no nutrient table is given.
2 not enough evidence
What was looked at
The 2 benefits and uses checked for Bay bolete, each with how strong the evidence is. Tap one to open it.
What is Bay bolete good for?
The uses people ask about and how strong the human evidence is for each. None is proven for bay bolete. Read this together with the Safety tab.
Benefits, one by one
Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.
Nutrition as a food
Not enough evidenceBay bolete is a wild edible mushroom. A 2025 Polish study measured what is in it: about 34 g of beta-glucan (a fibre in the cell wall) per 100 g dry weight, and more vitamin C (ascorbic acid) and citric acid than two other boletes tested. This describes the food. No trial shows a health benefit from eating it.
2 studiesEaten fresh and cooked, or dried and soaked. Drying removes water, so…
Studies, doses and limits
What the trials found
No human trial of eating bay bolete was found.
Results
Mean beta-glucan 34.0 g per 100 g dry weight (30.3 to 37.7 by region), against 46.6 for Boletus edulis (porcini) in the same study. Mean ascorbic acid 43.35 mg and citric acid 128.34 mg per 100 g dry weight; chitin about 22 g per 100 g. A Czech study found the mushroom concentrated potassium, phosphorus, rubidium, sulphur, selenium and silver relative to the soil. USDA has no bay bolete entry in the files we hold, so no nutrient table is given.
Why this rating
Composition data only; no study measured a health effect of eating bay bolete.
Form and dose studied
Eaten fresh and cooked, or dried and soaked. Drying removes water, so a figure per gram of dried mushroom is far higher than per gram of fresh. Always check which basis a number uses.
Who was studied
General food use
Limits
Wild samples differ by place and age. Two regions of one country were sampled; units for some compounds were read from tables.
Why researchers looked
Bay bolete is mainly a food. Most papers measure what it contains, or what it picks up from the soil, not what it does in people.
Traditional use
No traditional medicine use was confirmed in the sources we read.
Proposed mechanism Compositional analysis
Not applicable: this is a composition fact, not a mechanism.
A proposed mechanism does not show that the effect happens in people.
Wild bay bolete is among the strongest accumulators of radioactive caesium and can carry cadmium and arsenic; see the Safety tab.
Antioxidant activity in the test tube
Not enough evidenceIn a 2025 Polish study, extracts of dried bay bolete scored highest of three boletes in one antioxidant test tube assay (DPPH). The authors link this to vitamin C, citric acid and phenolic compounds. This is a laboratory result, not a finding in people.
1 studiesDried, ground mushroom extracts in the lab. No supplement was assesse…
Studies, doses and limits
Results
I. badia had the strongest DPPH result of the three boletes; Leccinum scabrum had the strongest ABTS and FRAP results. No effect on any marker in people was measured.
Why this rating
Test-tube assays only; no study in animals or people was found for bay bolete.
Form and dose studied
Dried, ground mushroom extracts in the lab. No supplement was assessed.
Limits
Antioxidant assays are chemical tests and do not show a benefit when eaten.
Why researchers looked
Researchers measure antioxidant capacity of mushroom extracts as a first look at what they contain.
Proposed mechanism Laboratory research
Radical-scavenging assays (DPPH, ABTS, FRAP) measure how well an extract neutralises a chemical dye in a test tube. In this study, antioxidant results tracked phenolic acids and small reducing acids. Cadmium was inversely linked to antioxidant potential.
A proposed mechanism does not show that the effect happens in people.
The same study notes the cadmium found in wild boletes and calls for monitoring.
Connections to the rest of health
How Bay bolete connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.
Explore every connection: goals, body systems, organs, symptoms, genes
E. Health conditions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Mushroom poisoning | Adverse effect or risk | Low certainty | Neoboletus poisoning report; no bay-bolete-specific look-alike source read. Preparation or compound: Look-alike boletes |
10 18 |
| Mushroom allergy | Adverse effect or risk | Low certainty | Title-only case report. Preparation or compound: Boletus badius |
3 9 |
F. Functional actions
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Antioxidant | Biological association | Not enough evidence | Test-tube assays only; no trial. Preparation or compound: Dried bay bolete extracts |
17 |
G. Root causes and contributing factors
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Environmental toxins | Moderate certainty | Among the strongest caesium accumulators in several European surveys; depends on location. Preparation or compound: Wild bay bolete (radiocaesium) |
20 11 6 7 | |
| Heavy metal exposure | Moderate certainty | Cadmium varied about a hundred-fold between locations; arsenic outliers reported. Preparation or compound: Wild and dried bay bolete |
1 12 2 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Norbadione A | Biological association | In vitro | Binds caesium ions in test-tube chemistry; assumed by the authors to be involved in caesium-137 accumulation. Preparation or compound: Fruiting body (per the lab papers; the abstracts do not name the species) |
5 8 14 |
| Beta-glucan, alpha-glucan and chitin | Biological association | Compositional analysis | Structural; no bay bolete health effect shown. Preparation or compound: Fruiting body |
17 |
| Ascorbic acid and citric acid | Biological association | In vitro | Linked by the authors to the strongest DPPH radical-scavenging result in the test tube. Preparation or compound: Fruiting body |
17 |
| Cadmium (contaminant) | Biological association | Compositional analysis | Contaminant taken up from soil and air deposits. Preparation or compound: Upper parts (caps) more than stalks |
1 17 |
| Caesium-137 (contaminant) | Biological association | Compositional analysis | Contaminant from old fallout. Preparation or compound: Caps higher than stipes in the Czech hot-spot study |
11 20 6 7 |
Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 25, 2026).
Evidence at a glance: what the research found for 2 outcomes
Each outcome below is one thing researchers measured. Certainty is how far the evidence can be trusted, not how well it works. The full studies are on the next tab.
The evidence
The research centre for Bay bolete. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).
How we rate evidence
High certainty
Several well-run trials or reviews agree; further research is unlikely to change the picture much.
Moderate certainty
Good trials point the same way, but some doubt remains.
Low certainty
Small, short or inconsistent trials. The finding could change with better research.
Very low certainty
Very little or very weak human data. Treat as a possibility only.
Mixed findings
Trials or reviews disagree with each other.
Not enough evidence
Not enough human research to say either way.
Evidence against
Good research found no benefit, or found harm.
We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We read PubMed records for 16 papers: abstracts for 14 (eleven contamination or composition surveys, one poisoning case report and two test-tube chemistry papers), and title-and-record only for two (a mushroom allergy case report and a letter). We also read three full texts for their tables (Czech elements, Polish bioactives, Polish radiocaesium) and two guidance pages (Missouri Department of Conservation and Penn State Extension), and checked the name in GBIF and a pigment in PubChem. Index Fungorum, EFSA, FDA and poison-centre statements were not read. Only abstracts were read for most papers, so numbers come from abstracts or the tables named. Certainty ratings are the compiler's own reading.
Study library: every study we checked 20
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Andronikov 2025 Effect of Compositionally Different Substrates on Elemental Properties of Bay Bolete Mushrooms: Case Study of 34 Essential and Non-essential Elements from Six Areas Affected Differently by Industrial Pollution. Biological Trace Element Research · PMID 39477854 · DOI |
Laboratory survey fungus (lab survey) |
Imleria badia and soil from six Czech forest locations on granite, amphibolite and peridotite | Wild Imleria badia fruiting bodies (caps, stipes, sporophore) fruiting body Not shown here |
The abstract says the mushrooms concentrated Ag, K, P, Rb, S and Se relative to the soil and held back most other elements, and that most elements were found mostly in the upper parts of the fruiting body, with Cd and Cu moving most. It says I. badia seems sensitive to taking up As, Cd and Pb from air deposits. In the full text, cadmium in mushroom samples ran from 0.07 to 0.4 mg per kg at the two amphibolite locations and from 0.2 to 23 mg per kg elsewhere, with the highest values (4.2 to 23 mg per kg) at one granite location. Cadmium in whole samples from the two granite locations was 1.9 to 12 mg per kg. Cadmium varied by about a hundred-fold between locations Methods, limits and fundingOutcomes: 34 elements, bioconcentration, within-mushroom distribution Limitations: Part of the data are in supplement files that were not opened; sampling year not found; dry or fresh basis not checked; six locations in one country. Funding and conflicts: Funded by the Czech Geological Survey (internal grant); conflict statement not fully read Read: abstract and full text |
| Domagalska 2026 Evaluation of Toxic Elements in Commercial Dried Mushrooms from the Polish Market: Exposure Assessment and Health Risk Characterization. Molecules · PMID 42280168 · DOI |
Laboratory survey fungus (lab survey) |
164 164 commercial dried mushroom samples, six species, Poland |
Dried commercial fruiting bodies incl. Imleria badia fruiting body Not shown here |
Contamination depended on species, supplier and certification. Median levels for most species were within the safety thresholds the authors used. The abstract reports an incidental extreme arsenic value of 369.048 mg per kg in one Imleria badia sample, with a hazard index of 63.57 against a limit of 1. Organic-certified samples had significantly lower mercury and arsenic. One extreme arsenic outlier in a bay bolete sample; large variation between suppliers Methods, limits and fundingOutcomes: Cd, Pb, Hg, As Limitations: Abstract only; Poland only; one sample, so it shows an outlier can occur, not how common it is; thresholds are the authors' own. Funding and conflicts: Authors declare no competing interests Read: abstract |
| Fischer 2017 Rare Ingestive Food Allergy to Mushroom Boletus badius. Acta Dermato-Venereologica · PMID 28597023 · DOI |
Case report human (case report) |
Short communication from a Munich allergy department (details not read) | Boletus badius, an older name for bay bolete fruiting body Not shown here |
Only the title and record were available; the abstract is missing. The title says it reports an uncommon allergy after eating Boletus badius. Nothing else is stated from it. Title only: a published allergy case after eating the mushroom Methods, limits and fundingOutcomes: Food allergy Limitations: No abstract or details read; the number of people, symptoms and tests are unknown. Funding and conflicts: Not stated Read: title and record only |
| GBIF 2026 GBIF Backbone Taxonomy: Imleria badia (Fr.) Vizzini (key 7832732), checked 2026-10-25 GBIF API · Source |
Taxonomy record n/a |
n/a | n/a Not shown here |
GBIF returns Imleria badia (Fr.) Vizzini as ACCEPTED (key 7832732), kingdom Fungi, phylum Basidiomycota, class Agaricomycetes, order Boletales, family Boletaceae, genus Imleria. Xerocomus badius (Fr.) Kuhner is listed as a SYNONYM of it, and Boletus badius (Fr.) Fr. (key 9048142) as a HETEROTYPIC_SYNONYM. Several other, unrelated names also spelled Boletus badius appear in GBIF and are not this mushroom. Methods, limits and fundingOutcomes: Accepted name and synonyms Limitations: A database record; Index Fungorum was not checked. Funding and conflicts: Public database Read: record |
| Garaudée 2002 Allosteric effects in norbadione A. A clue for the accumulation process of 137Cs in mushrooms? Chemical Communications · PMID 12123060 · DOI |
Laboratory research chemistry (in vitro) |
Chemistry in solution (no mushroom samples in the abstract) | Norbadione A, a mushroom pigment pigment Not shown here |
The abstract describes two caesium complexes of norbadione A (one with one caesium ion, one with two) and gives their stability constants at about pH 6. It reports that binding of the second caesium ion is helped by the first. The title asks whether this is a clue to how mushrooms accumulate caesium-137. Norbadione A binds caesium in test-tube chemistry Methods, limits and fundingOutcomes: Caesium complexes Limitations: Test-tube chemistry; the abstract does not name the mushroom species; a clue, as the title says, not proof of the mechanism in the living mushroom. Funding and conflicts: Research support from a government source (non-US); no competing interests stated Read: abstract |
| Grodzinskaya 2022 Radioactive Contamination of Wild Mushrooms from Ukraine under Conditions of Contrasting Radiation Loads: 36 Years after the Chernobyl Nuclear Power Plant Catastrophe. International Journal of Medicinal Mushrooms · PMID 36004707 · DOI |
Laboratory survey fungus (lab survey) |
Wild mushrooms from Drevlyanskyi Nature Reserve (Zhytomyr Polissya, Ukraine), sampled since 2013 | Wild fruiting bodies incl. Imleria badia fruiting body Not shown here |
The abstract says consumption of wild mushrooms in Ukrainian Polissya is still dangerous because the area is heavily contaminated. In the reserve, Imleria badia had the highest caesium-137 of the species listed, up to 2,680 kBq per kg dry mass, against up to 96 kBq per kg for Boletus edulis. At locations with low contamination, I. badia still reached 7,698 Bq per kg dry mass. The authors calculate annual doses for adults, counting caesium-137 only, of 8.71 mSv for I. badia from highly contaminated locations and 0.009 mSv from low ones. I. badia was the top accumulator at both heavily and lightly contaminated locations Methods, limits and fundingOutcomes: Caesium-137, strontium-90, estimated dose Limitations: Abstract only; the eating amounts behind the dose figures are not in the abstract; a reserve with an unusually heavy load is not typical of food on sale. Funding and conflicts: Not stated in the abstract Read: abstract |
| Harkut 2021 Radiocaesium Contamination of Mushrooms at High- and Low-Level Chernobyl Exposure Sites and Its Consequences for Public Health. Life (Basel) · PMID 34947901 · DOI |
Laboratory survey fungus (lab survey) |
Three mushroom species at a Czech Chernobyl hot spot (Opava, Silesia) and a low-exposure area (Beskydy), 2011 | Wild caps and stipes of Xerocomus badius (the older name for Imleria badia), Russula ochroleuca, Armillariella mellea fruiting body Not shown here |
The abstract says the highest caesium-137 was in caps of Xerocomus badius (11.8 kBq per kg) and Russula ochroleuca (8.77 kBq per kg) in the Opava area. The 134Cs/137Cs ratio confirmed the source. For X. badius the authors estimate a yearly dose from radiocaesium of at most 0.102 mSv in the Opava area and 0.004 mSv at the low-exposure area, and say this is not a significant public-health risk. Highest caesium in X. badius caps at the hot spot; estimated dose small Methods, limits and fundingOutcomes: Caesium-137 in caps and stipes, estimated dose Limitations: Abstract only; the dry or fresh basis is not stated in the abstract; one year (2011); the eating amount behind the dose is not in the abstract. Funding and conflicts: Authors declare no conflict of interest Read: abstract |
| Korovitch 2010 Norbadione a: kinetics and thermodynamics of cesium uptake in aqueous and alcoholic media. Journal of Physical Chemistry B · PMID 20831226 · DOI |
Laboratory research chemistry (in vitro) |
Chemistry in water and alcohol (no mushroom samples in the abstract) | Norbadione A, a mushroom pigment pigment Not shown here |
The abstract calls norbadione A a mushroom pigment that is assumed to be involved in caesium-137 accumulation across Europe after Chernobyl. It measures how fast and how tightly it binds caesium ions in ethanol, ethanol-water and water, and says the efficiency is comparable to some synthetic crown-ether-type compounds. Strong caesium binding by the pigment in test tubes Methods, limits and fundingOutcomes: Caesium binding kinetics Limitations: Test-tube chemistry; 'assumed to be involved' is the authors' wording; the abstract does not name the mushroom species. Funding and conflicts: Research support from a government source (non-US); no competing interests stated Read: abstract |
| Lee Qiyu 2026 Edible mushroom allergy: a clinically heterogeneous and under-recognized condition. European Annals of Allergy and Clinical Immunology · PMID 42788552 · DOI |
Letter human (letter) |
Edible mushrooms in general | Edible mushrooms (not bay-bolete-specific) fruiting body Not shown here |
Only the title and record were available; no abstract. The title says edible mushroom allergy is varied and under-recognised. Title only Methods, limits and fundingOutcomes: Allergy Limitations: No abstract or figures read; says nothing specific about bay bolete. Funding and conflicts: Not stated Read: title and record only |
| Li 2026 Beyond gastroenteritis: first evidence of systemic biochemical disturbances, predominantly coagulation dysfunction, in Neoboletus poisoning. Toxicon · PMID 42476469 · DOI |
Case report human (case report) |
8 Two poisoning episodes in Yunnan, China (2022 and 2023), eight people who ate wild boletes |
Wild mushrooms of the bolete genus Neoboletus, not bay bolete fruiting body Not shown here |
In the first episode four adults ate one wild species and one had abdominal pain, dizziness and sweating that settled within an hour. In the second, a mixed wild meal was eaten by four people and three had vomiting and tiredness. In the two men who ate most, blood tests showed longer thrombin time (up to 37.5 seconds), high blood sugar (up to 11.3 mmol/L), raised creatine kinase, and mild liver and kidney or metabolic changes, rising with the amount eaten. The authors say one of these species is traditionally eaten in parts of China. Dose-related multi-system blood changes, mainly clotting, after eating certain boletes Methods, limits and fundingOutcomes: Symptoms and blood tests Limitations: About boletes of another genus; says nothing about bay bolete look-alikes; two small incidents; abstract only. Funding and conflicts: Authors declare no competing interests Read: abstract |
| Mirończuk-Chodakowska 2025 Forty Years After Chernobyl: Radiocaesium in Wild Edible Mushrooms from North-Eastern Poland and Its Relevance for Dietary Exposure and Food Safety. Toxics · PMID 40711045 · DOI |
Laboratory survey fungus (lab survey) |
230 230 wild mushroom samples, 19 species, north-eastern Poland (31 of them Imleria badia) |
Wild fruiting bodies incl. Imleria badia (gamma spectrometry) fruiting body Not shown here |
Across all species caesium-137 ranged from 0.94 to 159.0 Bq per kg fresh mass and no sample went over the 1,250 Bq per kg limit. In the full text, the 31 Imleria badia samples had a median of 61.9 Bq per kg fresh mass (middle half 39.8 to 79.8) and a median of 696.4 Bq per kg dry mass. The paper places I. badia in the group with high caesium accumulation, with Sarcodon imbricatus and Cortinarius caperatus, and says its levels were roughly eight times lower than in earlier Polish studies (2006), which it links to the time gap. It notes that Euratom 2016/52 requires dried products to be judged in their reconstituted form, and says that after this adjustment even the most contaminated dried samples complied. The highest estimated yearly dose was 2.32 microsieverts from caesium-137. Bay bolete was among the higher accumulators in the region, with all samples under the regulatory limit Methods, limits and fundingOutcomes: Caesium-137, potassium-40, dose Limitations: Fresh-mass table values read from the full text; one region and period; the authors' dose scenarios are theirs. Funding and conflicts: Authors declare no conflicts of interest; the research received no external funding Read: full text |
| Niedzielski 2013 Selected arsenic species: As(III), As(V) and dimethylarsenic acid (DMAA) in Xerocomus badius fruiting bodies. Food Chemistry · PMID 23993523 · DOI |
Laboratory survey fungus (lab survey) |
Xerocomus badius (the older name for Imleria badia) from Polish forests with very low or high human pressure, plus commercial samples | Wild and commercial fruiting bodies fruiting body Not shown here |
The abstract reports arsenic as high as 27.1 mg per kg As(III), 40.5 As(V) and 88.3 DMAA in mushrooms from areas with high human pressure and in two commercial samples. In mushrooms from lightly affected areas and two other commercial samples each arsenic form was below 0.5 mg per kg. The authors say arsenic can reach concentrations toxic for humans and should be monitored in mushroom foods. Arsenic was very high at some polluted areas and in two commercial samples, and low elsewhere Methods, limits and fundingOutcomes: Arsenic species Limitations: Abstract only; 2013 data; dry or fresh basis not stated in the abstract. Funding and conflicts: Not stated in the abstract Read: abstract |
| Orywal 2021 Health risk assessment of exposure to toxic elements resulting from consumption of dried wild-grown mushrooms available for sale. PLoS One · PMID 34161345 · DOI |
Laboratory survey fungus (lab survey) |
Dried wild-grown mushrooms on sale (Boletus edulis and Xerocomus badius) | Dried fruiting bodies fruiting body Not shown here |
In dried Xerocomus badius (the older name for Imleria badia) the means were 0.102 mg per kg mercury, 1.154 cadmium, 0.928 lead and 0.278 arsenic. Boletus edulis had higher mercury (3.039) and cadmium (1.983). The health-risk calculation highlighted dried Boletus edulis, not X. badius. The authors say EU rules set no maximum content of elements for dried wild mushrooms and that the contents should be monitored. Dried X. badius carried cadmium and lead in the low mg per kg range Methods, limits and fundingOutcomes: Hg, Cd, Pb, As, hazard index Limitations: Abstract only; one country; samples bought for sale, origin not given in the abstract. Funding and conflicts: Authors declare no competing interests Read: abstract |
| PubChem 2026 PubChem: norbadione A (name search returned CID 54679293), checked 2026-10-25 PubChem API · Source |
Chemistry record n/a |
n/a | n/a Not shown here |
A PubChem name search for 'norbadione A' returned CID 54679293, formula C35H18O15. Methods, limits and fundingOutcomes: Compound identity Limitations: A chemistry record only; the record title is a systematic name, not 'norbadione A'; it does not say which mushroom contains it. Funding and conflicts: Public database Read: record |
| Ronda 2022 Accumulation of radioisotopes and heavy metals in selected species of mushrooms. Food Chemistry · PMID 34359008 · DOI |
Laboratory survey fungus (lab survey) |
Seven forest mushroom species from several Polish regions | Wild fruiting bodies incl. Imleria badia (edible) and Tylopilus felleus (inedible) fruiting body Not shown here |
The abstract lists Imleria badia among four edible species tested, with three inedible species including the bitter bolete Tylopilus felleus. The authors compared results with EFSA recommendations and European radioisotope standards and conclude that eating mushrooms may lead to significantly exceeding consumption limits for cadmium, copper and caesium-137. The abstract does not give a result for I. badia alone. Consumption limits for Cd, Cu and Cs-137 could be exceeded for mushrooms as a group Methods, limits and fundingOutcomes: Cs-137, K-40, metals Limitations: Abstract only; no species-specific numbers in the abstract. Funding and conflicts: Not stated in the abstract Read: abstract |
| Skibniewski 2025 The Assessment of Mercury Concentrations in Two Species of Edible Forest Mushrooms, Aureoboletus projectellus and Imleria badia, and Their Impact on Consumers' Health. Foods · PMID 40002075 · DOI |
Laboratory survey fungus (lab survey) |
Two edible bolete species from the central coast of Poland | Wild Imleria badia caps and stipes fruiting body Not shown here |
Mercury in Imleria badia was 0.055 mg per kg dry matter in caps and 0.025 in stipes. The authors conclude the two species do not pose a mercury risk to consumers and that the area is free of mercury pollution. Low mercury; caps higher than stipes Methods, limits and fundingOutcomes: Total mercury Limitations: Mercury only; one area; abstract only. Funding and conflicts: Authors declare no conflicts of interest Read: abstract |
| Sotek 2025 Bioactive Compounds and Antioxidant Activity of Boletus edulis, Imleria badia, Leccinum scabrum in the Context of Environmental Conditions and Heavy Metals Bioaccumulation. Molecules · PMID 40807452 · DOI |
Laboratory survey fungus (lab survey) |
Three wild bolete species from two forest regions of north-western Poland | Dried, ground wild fruiting bodies incl. Imleria badia fruiting body Not shown here |
The abstract says I. badia had the highest ascorbic and citric acid and the strongest DPPH radical-scavenging (a test-tube antioxidant test) of the three species. In the full text, I. badia held a mean of 34.0 g beta-glucan per 100 g dry weight (30.3 to 37.7 by region; 46.6 for B. edulis), 43.35 mg ascorbic acid and 128.34 mg citric acid per 100 g, and a mean cadmium of 0.43 mg per kg against 2.74 for B. edulis. The abstract says all metal concentrations stayed inside EU food-safety limits, and that B. edulis, not I. badia, showed consistent cadmium bioaccumulation. Antioxidant activity tracked phenolic acids, and cadmium was inversely linked to it. Composition data and test-tube antioxidant results only Methods, limits and fundingOutcomes: Glucans, acids, antioxidant assays, Cd/Pb/Ni Limitations: Test-tube assays say nothing about effects in people; dry-weight basis assumed for the metal units; two regions of one country. Funding and conflicts: Authors declare no conflicts of interest Read: abstract and full text |
| n/a 2024 Penn State Extension: Preparing and Preserving Mushrooms (updated 22 November 2024) extension.psu.edu · Source |
Authoritative guidance n/a |
n/a | n/a Not shown here |
Page text read on 2026-10-25 for the porcini page. Says only an expert can tell poisonous from edible mushrooms, that unless you are an expert you should not forage your own, and that no matter how much you cook or dry mushrooms you will not destroy their toxins. It says not to can wild mushrooms. Methods, limits and fundingOutcomes: Identification and safety statements Limitations: University extension page about mushrooms in general; US food-safety guidance, not specific to bay bolete. Funding and conflicts: University extension (public) Read: full text |
| n/a 2026 Missouri Department of Conservation: Bitter Bolete (field guide page) mdc.mo.gov · Source |
Authoritative guidance n/a |
n/a | n/a Not shown here |
Page text read on 2026-10-25 for the porcini page and re-checked here. It lists the bitter bolete (Tylopilus felleus) as not recommended or not edible and says it can be extremely bitter. It says this species resembles the king bolete (Boletus edulis). It says to be absolutely sure of the ID of any mushroom. It does not mention the bay bolete. Methods, limits and fundingOutcomes: Identification and safety statements Limitations: State conservation agency field guide for Missouri; not a poison-centre or regulator statement; says nothing about bay bolete; no date on the page. Funding and conflicts: Public agency Read: full text |
| Šlemar 2026 Investigation of long-term caesium-137 radioactivity in fungal species of the Czech Republic. Radiation and Environmental Biophysics · PMID 42573753 · DOI |
Laboratory survey fungus (lab survey) |
25 mushroom species from seven Czech forest locations, collected in 2023 | Wild fruiting bodies incl. Imleria badia (gamma spectrometry) fruiting body Not shown here |
The abstract says Imleria badia had the highest caesium-137 of the 25 species, up to 7,842 Bq per kg of dry mass, which the authors describe as 63 percent below the EU safety threshold. Other mycorrhizal Boletales followed, including Boletus edulis, Tylopilus felleus and Suillus grevillei. No sample went over the 1,250 Bq per kg fresh-mass limit in Council Regulation Euratom 2016/52, but two I. badia samples went over the 600 Bq per kg fresh-mass import limit in Commission Regulation (EU) 2020/1158. The authors estimate an adult's dose is well below 1 mSv a year and call the risk minimal. I. badia was the strongest caesium accumulator of 25 species; two samples were over the import limit Methods, limits and fundingOutcomes: Caesium-137 activity, estimated dose Limitations: Dry-mass and fresh-mass bases are mixed in the abstract; regulation texts were not opened; abstract only. One year of sampling (2023), Czech Republic only. Funding and conflicts: Authors declare no competing interests Read: abstract |
What we do not know yet
- No human trial of bay bolete for any health outcome was found.
- No source naming poisonous look-alikes of bay bolete was read.
- No regulatory text was opened; the caesium limits are quoted from a paper's abstract.
- No study of cooking, soaking or drying effects on caesium or metals in bay bolete was found, and no data on allergy rates, pregnancy or breastfeeding, or powders, extracts and capsules.
- Survey figures are for particular places and years and may not match any product you buy.
How new research is added
New studies are found by a saved PubMed search and placed in a review queue. A person reads each one before it changes any evidence rating or safety wording. New publications never change ratings automatically.
Lab markers
What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 4
- Wild bay bolete is among the strongest accumulators of radioactive caesium. Bay bolete takes up caesium-137 from forest soil more than most edible mushrooms. In a Czech survey of 25 species it had the highest level, up to 7,842 Bq per kg dry mass, and two samples went over the EU 600 Bq per kg fresh-mass import limit as the abstract states. In Polish samples (31 of them) the median was 61.9 Bq per kg fresh mass and none went over the 1,250 Bq per kg limit. In a heavily contaminated Ukrainian reserve it reached 2,680 kBq per kg dry mass, and the authors there call eating wild mushrooms in that region still dangerous. The amount in the mushroom depends mainly on where it grew, so a result from one place says little about another. Laboratory survey 20 11 6 7
- Wild mushrooms can be mistaken for others, and cooking does not remove toxins. Penn State Extension says only an expert can tell poisonous from edible mushrooms, that you should not forage your own unless you are one, and that cooking or drying does not destroy toxins. The Missouri Department of Conservation lists the bitter bolete as not edible and extremely bitter; a 2022 Polish study also lists it as inedible. A 2026 report describes people poisoned in China by other wild boletes (the genus Neoboletus), with changes in blood clotting and blood sugar. That report is not about bay bolete and does not say they look alike. We read no source naming bay-bolete-specific poisonous look-alikes, so none is named here. Never eat a wild mushroom on the strength of a web page or an app. Authoritative guidance 18 19 10 15
- Cadmium and arsenic vary hugely by place, and outliers exist. Cadmium in Czech bay bolete ran from 0.07 to 23 mg per kg depending on the location (highest at one granite location). In north-western Poland the mean was 0.43 mg per kg, lower than porcini (2.74) in the same study. Mercury was low (0.055 mg per kg in caps). Arsenic was very high in Xerocomus badius from some polluted Polish areas and in two commercial samples (up to 88.3 mg per kg of one form), and one dried bay bolete in a 2026 market survey held 369 mg per kg arsenic, far above the authors' safety limit. Organic-certified products had lower mercury and arsenic in that survey. Laboratory survey 1 17 16 12 2
- Allergy to the mushroom has been reported. A 2017 short communication is titled as a rare ingestive food allergy to Boletus badius, an older name for bay bolete. Only the title was available to us. Mushroom allergy in general is described by another letter as varied and under-recognised. Wheezing, swelling or hives after eating mushrooms need emergency care. Case report 3 9
Side effects 3
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| Radiation dose from eating contaminated wild bay bolete These are authors' calculated doses from mushroom measurements and assumed eating amounts. No illness from eating bay bolete radiocaesium was reported in the sources read. | Estimated, not measured in people: for Xerocomus badius at a Czech hot spot, 0.102 mSv a year against 0.004 at a low-exposure area; in a Ukrainian reserve, 8.71 mSv a year in the authors' scenario (caesium-137 only) | Depends on location and amount; small for typical Czech and Polish samples, large for the heavily contaminated reserve Not applicable (a cumulative dose estimate) | Laboratory survey 7 6 20 |
| Poisoning from look-alike boletes (sickness, dizziness, sweating; clotting changes in poisonings by other bolete species) The report is about Neoboletus boletes, not bay bolete, and it does not say they look like bay bolete. | Not found for bay bolete look-alikes; the 2026 Neoboletus report covers 8 people | mild to moderate in the report The first episode settled within an hour; follow-up of the second was not in the abstract | Case report 10 |
| Allergic reaction after eating Only titles and records were read. | Not found | unknown unknown | Case report 3 9 |
Liver
No liver injury from eating bay bolete was found in the sources read. Mild liver blood-test changes occurred in a Neoboletus poisoning report, which was a different mushroom. 10
Monitoring. Seek medical care for poisoning signs; no routine monitoring is suggested by the sources read.
- p42476469.
This is a safety connection. It is not evidence that Bay bolete supports liver health.
Medicines and supplements 2
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Prescription and over-the-counter medicines prescription | No interaction report for bay bolete was found in the sources read. This is absence of evidence, not proof of safety. | None found Not enough evidence | Ask a pharmacist if you take regular medicines and plan to eat large amounts of any wild mushroom. | |
| Low-oxalate diets (for example after kidney stones) condition | Inference only from composition: the 2025 Polish study measured oxalic acid in bay bolete (25 to 43 mg per 100 g dry weight by region) and notes oxalic acid can bind minerals such as calcium and iron. | No source linked bay bolete to kidney stones or low minerals. Raised only because the compound is present. | Theoretical Very low certainty 17 | If you have been told to limit oxalate, ask your doctor or dietitian about large amounts of any mushroom. |
Who should check first 4
| Situation | Advice | Evidence |
|---|---|---|
| Anyone who cannot be sure of the mushroom's identity | Do not eat it. Only an expert can separate poisonous from edible mushrooms, and cooking or drying does not destroy toxins (Penn State Extension). | Authoritative guidance 18 19 |
| Known mushroom allergy | Ask an allergy specialist before eating. | Case report 3 9 |
| Pregnancy, breastfeeding and young children | No bay-bolete-specific safety data were found. Wild mushrooms can carry caesium and metals, and small bodies get a bigger dose per kilo, so ask a clinician before giving wild or dried mushrooms to these groups. | Theoretical |
| Living or collecting in an area with high radioactive fallout or industrial pollution | Levels in the mushroom rose with local contamination, so local health authorities' advice is the right guide. | Laboratory survey 6 1 12 |
Overdose, product quality and regulators
Summary. Bay bolete is a widely eaten edible mushroom. The hazards in the sources read are caesium-137, cadmium and arsenic taken up from the soil, mistaken identity of wild mushrooms, and allergy, not a toxin made by the mushroom itself.
Animal. Not reviewed.
Human doses studied. No dose studies. No amounts are advised here.
High dose or long term signals. Authors estimate radiation doses and metal intakes from measured levels; no harm was measured in people in the papers read.
Genotoxicity. Not read.
Toxic or hazardous parts. Fungus: cap and stalk are eaten. Cadmium and mercury were higher in the upper parts (caps) than in stalks in the studies read.
Bay bolete is wild-collected, so what it carries depends on the soil, the air deposits and the year. Dried products are concentrated: drying removes water, so a result per kg of dried mushroom is far higher than a per-kg-fresh figure for the same mushroom, and every number must be read with its basis.
Radiocaesium (caesium-137) across Europe. Highest of 25 species in a Czech survey (up to 7,842 Bq per kg dry mass); in the high group in north-eastern Poland (median 61.9 Bq per kg fresh, about eight times lower than in earlier Polish work, which the authors link to time passing); caps up to 11.8 kBq per kg at a Czech hot spot; up to 2,680 kBq per kg dry mass in a Ukrainian reserve, and still 7,698 Bq per kg dry mass at lightly contaminated Ukrainian locations. A related species, Boletus edulis (porcini), was lower at the same Ukrainian reserve (up to 96 kBq per kg). 20 11 7 6
Why bay bolete holds caesium (lab chemistry). A pigment called norbadione A binds caesium ions in test-tube chemistry, and the authors say it is assumed to be involved in caesium accumulation in mushrooms. This is a proposed explanation from chemistry in solution, not proof, and the abstracts do not name the mushroom species. 5 8 14
Cadmium and other metals. Cadmium ranged from 0.07 to 23 mg per kg across Czech locations, with the highest at one granite location. Bay bolete concentrated silver, potassium, phosphorus, rubidium, sulphur and selenium relative to soil. In Poland cadmium averaged 0.43 mg per kg against 2.74 for porcini. In dried retail Xerocomus badius, means were 1.154 mg per kg cadmium and 0.928 lead. Authors of a seven-species Polish study say eating mushrooms may exceed consumption limits for cadmium, copper and caesium-137. 1 17 13 15
Mercury and arsenic. Mercury was low (0.055 mg per kg in caps). Arsenic was high in Xerocomus badius from some polluted Polish areas and in two commercial samples, and one dried Imleria badia sample in a 2026 survey had 369 mg per kg arsenic, a hazard index of 63.57 against a limit of 1. That is an outlier in one sample, not typical. 16 12 2
Dried mushrooms and rules. The Polish north-east study notes that Euratom 2016/52 requires dried products to be judged in their reconstituted form, and says that after this adjustment the most contaminated dried samples complied. A 2021 study says EU rules set no maximum content of elements for dried wild mushrooms. Cooking or soaking effects on caesium in bay bolete specifically were not found. 11 13
| Body | Action | Date |
|---|---|---|
| Missouri Department of Conservation (United States (state)) | Field guide page lists the bitter bolete as not edible and extremely bitter and says it resembles the king bolete. It does not mention the bay bolete. Not a regulator statement about bay bolete. source | 2026-10-25 |
| Penn State Extension (United States (university)) | Says only an expert can tell poisonous from edible mushrooms, that cooking or drying will not destroy toxins, and not to can wild mushrooms. source | 2024-11-22 |
When to get medical help
- Severe or repeated vomiting, diarrhoea or belly pain, dizziness, confusion or heavy sweating after eating a wild mushroom: get emergency medical help or call your local poison service now. Do not wait for it to pass.
- Unusual bleeding, easy bruising, passing very little urine, yellow skin or eyes, or dark urine after eating wild mushrooms: get medical help now.
- Wheezing, chest tightness, swelling of the lips or face, or hives after eating mushrooms: treat as an emergency.
If someone may be poisoned or in a crisis, contact a clinician or emergency service straight away. In the US, Poison Control is 1-800-222-1222.
General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.
Frequently asked questions
What is bay bolete?
Bay bolete is Imleria badia, a wild edible mushroom, also called Boletus badius or Xerocomus badius in older papers. It is eaten fresh or dried; the papers we read come from the Czech Republic, Poland and Ukraine.
Is bay bolete healthy?
It is a food rich in fibre such as beta-glucan and has vitamin C, according to a 2025 Polish study. No human trial shows a specific health benefit from eating it.
Is wild bay bolete radioactive?
It can hold radioactive caesium-137 from old fallout, and it is one of the strongest mushrooms at taking it up. In a Czech survey it had the highest level of 25 species, while in north-eastern Poland the median was 61.9 Bq per kg fresh, under the 1,250 limit. In a heavily contaminated Ukrainian reserve it reached 2,680 kBq per kg dry mass.
Is it safe to eat bay bolete from my area?
Does bay bolete contain heavy metals?
What mushrooms look like bay bolete?
Can other boletes poison you?
Does cooking or drying remove caesium or metals?
We found no study of this for bay bolete. Drying removes water, so a figure per kg of dried mushroom is much higher than per kg of fresh. A Polish study notes EU rules judge dried products in their reconstituted form.
Can you be allergic to bay bolete?
Is bay bolete safe in pregnancy, breastfeeding or for children?
No bay-bolete-specific safety data were found. Ask a clinician about wild or dried mushrooms in these groups.
Does bay bolete interact with medicines?
No interaction report was found in the sources we read, which is not proof of safety. Ask a pharmacist if you take regular medicines.
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Editorial transparency
- Written by
- AlternativeMed editorial team. Research compiled with AI assistance, then checked against PubMed records.
- Medical review
- None. This page has not been reviewed by a physician or pharmacist.
- First published
- 2026-10-25
- Last substantive update
- 2026-10-25
- How we research
- We read PubMed records for 16 papers: abstracts for 14 (eleven contamination or composition surveys, one poisoning case report and two test-tube chemistry papers), and title-and-record only for two (a mushroom allergy case report and a letter). We also read three full texts for their tables (Czech elements, Polish bioactives, Polish radiocaesium) and two guidance pages (Missouri Department of Conservation and Penn State Extension), and checked the name in GBIF and a pigment in PubChem. Index Fungorum, EFSA, FDA and poison-centre statements were not read. Only abstracts were read for most papers, so numbers come from abstracts or the tables named. Certainty ratings are the compiler's own reading.
- How we rate evidence
- See "How we rate evidence" in the Evidence tab.
- Independence
- No product is promoted on this page. No affiliate links are shown. This page is information, not a recommendation to eat wild mushrooms.
Sources 20
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
- Andronikov AV, Andronikova IE, Sebek O, et al. Effect of Compositionally Different Substrates on Elemental Properties of Bay Bolete Mushrooms: Case Study of 34 Essential and Non-essential Elements from Six Areas Affected Differently by Industrial Pollution.. Biological Trace Element Research. 2025. PMID 39477854. DOI 10.1007/s12011-024-04429-5. (abstract and full text)
- Domagalska J, Rusin M, Rogala D, et al. Evaluation of Toxic Elements in Commercial Dried Mushrooms from the Polish Market: Exposure Assessment and Health Risk Characterization.. Molecules. 2026. PMID 42280168. DOI 10.3390/molecules31111865. (abstract)
- Fischer T, Eberlein B, Brockow K, et al. Rare Ingestive Food Allergy to Mushroom Boletus badius.. Acta Dermato-Venereologica. 2017. PMID 28597023. DOI 10.2340/00015555-2721. (title and record only)
- GBIF. GBIF Backbone Taxonomy: Imleria badia (Fr.) Vizzini (key 7832732), checked 2026-10-25. GBIF API. 2026. (record)
- Garaudée S, Elhabiri M, Kalny D, et al. Allosteric effects in norbadione A. A clue for the accumulation process of 137Cs in mushrooms?. Chemical Communications. 2002. PMID 12123060. DOI 10.1039/b201929a. (abstract)
- Grodzinskaya AA, Nebesnyi VB, Landin VP, Gabriel J. Radioactive Contamination of Wild Mushrooms from Ukraine under Conditions of Contrasting Radiation Loads: 36 Years after the Chernobyl Nuclear Power Plant Catastrophe.. International Journal of Medicinal Mushrooms. 2022. PMID 36004707. DOI 10.1615/IntJMedMushrooms.2022044725. (abstract)
- Harkut O, Alexa P, Uhlář R. Radiocaesium Contamination of Mushrooms at High- and Low-Level Chernobyl Exposure Sites and Its Consequences for Public Health.. Life (Basel). 2021. PMID 34947901. DOI 10.3390/life11121370. (abstract)
- Korovitch A, Mulon JB, Souchon V, et al. Norbadione a: kinetics and thermodynamics of cesium uptake in aqueous and alcoholic media.. Journal of Physical Chemistry B. 2010. PMID 20831226. DOI 10.1021/jp1060232. (abstract)
- Lee Qiyu ML, Song Chia J. Edible mushroom allergy: a clinically heterogeneous and under-recognized condition.. European Annals of Allergy and Clinical Immunology. 2026. PMID 42788552. DOI 10.23822/EurAnnACI.1764-1489.452. (title and record only)
- Li J, Lu YT, Li XJ, et al. Beyond gastroenteritis: first evidence of systemic biochemical disturbances, predominantly coagulation dysfunction, in Neoboletus poisoning.. Toxicon. 2026. PMID 42476469. DOI 10.1016/j.toxicon.2026.109224. (abstract)
- Mirończuk-Chodakowska I, Kapała J, Kujawowicz K, et al. Forty Years After Chernobyl: Radiocaesium in Wild Edible Mushrooms from North-Eastern Poland and Its Relevance for Dietary Exposure and Food Safety.. Toxics. 2025. PMID 40711045. DOI 10.3390/toxics13070601. (full text)
- Niedzielski P, Mleczek M, Magdziak Z, et al. Selected arsenic species: As(III), As(V) and dimethylarsenic acid (DMAA) in Xerocomus badius fruiting bodies.. Food Chemistry. 2013. PMID 23993523. DOI 10.1016/j.foodchem.2013.06.103. (abstract)
- Orywal K, Socha K, Nowakowski P, et al. Health risk assessment of exposure to toxic elements resulting from consumption of dried wild-grown mushrooms available for sale.. PLoS One. 2021. PMID 34161345. DOI 10.1371/journal.pone.0252834. (abstract)
- PubChem. PubChem: norbadione A (name search returned CID 54679293), checked 2026-10-25. PubChem API. 2026. (record)
- Ronda O, Grządka E, Ostolska I, et al. Accumulation of radioisotopes and heavy metals in selected species of mushrooms.. Food Chemistry. 2022. PMID 34359008. DOI 10.1016/j.foodchem.2021.130670. (abstract)
- Skibniewski M, Skibniewski B, Lasocka I, Skibniewska E. The Assessment of Mercury Concentrations in Two Species of Edible Forest Mushrooms, Aureoboletus projectellus and Imleria badia, and Their Impact on Consumers' Health.. Foods. 2025. PMID 40002075. DOI 10.3390/foods14040631. (abstract)
- Sotek Z, et al. Bioactive Compounds and Antioxidant Activity of Boletus edulis, Imleria badia, Leccinum scabrum in the Context of Environmental Conditions and Heavy Metals Bioaccumulation.. Molecules. 2025. PMID 40807452. DOI 10.3390/molecules30153277. (abstract and full text)
- n/a. Penn State Extension: Preparing and Preserving Mushrooms (updated 22 November 2024). extension.psu.edu. 2024. (full text)
- n/a. Missouri Department of Conservation: Bitter Bolete (field guide page). mdc.mo.gov. 2026. (full text)
- Šlemar D, Litomiská B, Řezanka P. Investigation of long-term caesium-137 radioactivity in fungal species of the Czech Republic.. Radiation and Environmental Biophysics. 2026. PMID 42573753. DOI 10.1007/s00411-026-01244-5. (abstract)
