Mirończuk-Chodakowska et al. 2013 — Cadmium and lead in wild and cultivated mushrooms, eastern Poland
This study measured cadmium (Cd) and lead (Pb) in 21 edible mushroom species from the low-industry eastern region of Poland known as the Green Lungs, comparing 18 wild-harvested species from Podlaskie Province against 3 commercially cultivated species. Wild mushrooms exhibited wide interspecies variability for Cd (0.10–10.20 µg/g DM) while Pb concentrations were generally below EU tolerance limits; two wild species (Rozites caperatus and Boletus chrysenteron) accumulated Cd at levels whose daily intake from a 100 g fresh-weight serving could marginally exceed the provisional tolerable monthly intake (PTMI) established by FAO/WHO JECFA. Cultivated mushrooms showed markedly lower heavy metal burdens, particularly for Pb, with all cultivated species well below EU regulatory thresholds.
Key numbers
Concentrations expressed as µg/g dry mass (DM) unless noted; fresh mass (FM) values also given where relevant. n = 3 specimens per species.
Wild mushrooms — Lead (Pb, µg/g DM), mean ± SD:
- Tricholoma portentosum: 0.14 ± 0.13 (lowest)
- Boletus chrysenteron: 0.15 ± 0.05
- Suillus grevillei: 0.21 ± 0.09
- Suillus luteus: 0.33 ± 0.03
- Boletus subtomentosus: 0.30 ± 0.18
- Suillus bovinus: 0.27 ± 0.15
- Lactarius deliciosus: 0.34 ± 0.17
- Leccinum aurantiacum: 0.38 ± 0.20
- Leccinum scabrum: 0.37 ± 0.22
- Cantharellus cibarius: 0.47 ± 0.15
- Boletus edulis: 0.47 ± 0.38
- Boletus badius: 0.59 ± 0.37
- Tricholoma flavovirens: 1.39 ± 0.62
- Armillaria mellea: 0.16 ± 0.13
- Russula heterophylla: 2.03 ± 1.70
- Macrolepiota procera: 2.08 ± 1.80
- Rozites caperatus: 0.37 ± 0.18
- Russula vinosa: 2.61 ± 2.06 (highest)
EU tolerance limit for Pb in cultivated mushrooms: 0.3 µg/g FM (EC No. 629/2008). All wild mushroom Pb values remained below this FM-basis limit (FM values ranged 0.01–0.30 µg/g FM).
Wild mushrooms — Cadmium (Cd, µg/g DM), mean ± SD:
- Russula heterophylla: 0.10 ± 0.06 (lowest)
- Cantharellus cibarius: 0.41 ± 0.14
- Suillus bovinus: 0.22 ± 0.09
- Leccinum aurantiacum: 0.44 ± 0.26
- Russula vinosa: 0.32 ± 0.12
- Boletus badius: 0.51 ± 0.24
- Suillus luteus: 0.58 ± 0.27
- Leccinum scabrum: 0.79 ± 0.43
- Boletus subtomentosus: 0.91 ± 0.27
- Suillus grevillei: 2.28 ± 0.56
- Macrolepiota procera: 1.76 ± 0.78
- Armillaria mellea: 4.53 ± 1.20
- Tricholoma portentosum: 1.79 ± 0.34
- Tricholoma flavovirens: 1.11 ± 0.37
- Lactarius deliciosus: 2.79 ± 0.65
- Boletus edulis: 3.70 ± 1.53
- Rozites caperatus: 9.29 ± 2.93
- Boletus chrysenteron: 10.20 ± 4.01 (highest)
EU tolerance limit for Cd in mushrooms other than Agaricus bisporus, Pleurotus ostreatus, and Lentinus edodes: 1 µg/g FM (EC No. 629/2008). On an FM basis, all species except Rozites caperatus (0.68 µg/g FM) and Boletus chrysenteron (0.61 µg/g FM) fall below 0.2 µg/g FM. Per-FM comparisons to the 1 µg/g FM EU limit: all fresh-weight values are below the EU FM limit; the DM values for Rozites caperatus and Boletus chrysenteron are elevated because of their very high moisture content (91–93%).
Cultivated mushrooms — Pb and Cd (µg/g DM), mean ± SD:
- Agaricus bisporus (white): Pb = 0.03 ± 0.01; Cd = 0.09 ± 0.04
- Lentinus edodes: Pb = 0.12 ± 0.05; Cd = 0.42 ± 0.09
- Pleurotus ostreatus: Pb = 0.03 ± 0.01; Cd = 1.20 ± 0.34
All cultivated species below EU limits for both Pb (0.3 µg/g FM) and Cd (0.2 µg/g FM for Agaricus bisporus, Lentinus edodes; 0.2 µg/g FM applies). Pleurotus ostreatus Cd at 0.10 µg/g FM remains below 0.2 µg/g FM EU limit for this genus.
Dietary intake estimates (daily, per 100 g FM, 70 kg consumer):
- Highest Cd intake: Rozites caperatus = 0.068 mg/100g FM; Boletus chrysenteron = 0.061 mg/100g FM
- PTMI for Cd (FAO/WHO JECFA): 0.025 mg/kg BW/month → PDI = 0.056 mg/day for 70 kg adult
- Both Rozites caperatus and Boletus chrysenteron exceed the PTMI-derived PDI from a single 100 g FM serving
- Highest Pb intake: Macrolepiota procera = 0.0295 mg/100g FM; well below PTWI (equivalent to 0.214 mg/day)
Average moisture content across all 21 species: 90.8% FM (range 82.0–95.7%).
Methods (brief)
Wild mushrooms collected from 6 communal areas in Podlaskie Province during 2007–2010; 3 specimens per species, harvested in distant locations to avoid same-mycelium origin, fully developed and non-verminated. Cultivated mushrooms purchased from local food markets. Dried in air-dryer to constant mass, pulverized. Approximately 0.300 g dry sample digested in concentrated HNO3 by microwave (Speedwave, Berghof). ICP-MS analysis (NexION 300D, Perkin Elmer). Certified reference material: Corn Flour INCT-CF-3. Detection limits: Pb = 0.16 µg/L; Cd = 0.017 µg/L. Repeatability (CV): Pb = 2.6%; Cd = 3.5%. Concentrations expressed on both DM and FM basis; moisture determined per sample. Chemical equivalents (molecular weight/valence) used to rank co-contamination by Pb + Cd.
No speciation performed; total Pb and total Cd reported. Study does not cover Hg, As, or other metals. Small sample size per species (n = 3) limits statistical inference; high SD values in several species (e.g., Russula vinosa Pb SD = ±2.06) indicate substantial intraspecies variability.
Implications
Certification: Rozites caperatus and Boletus chrysenteron are the highest-risk wild mushroom species for Cd in this uncontaminated Polish forest context; concentrations 12-fold lower than near-industrial sites confirm significant background-level accumulation is a species-specific property independent of pollution proximity. This species hierarchy is relevant to any certification or labeling involving wild-harvested mushrooms.
Courses: Demonstrates that “uncontaminated area” does not mean “low Cd” for all mushroom species; Boletus chrysenteron and Rozites caperatus consistently accumulate Cd at elevated levels due to intrinsic physiology. Boiling or microwaving with water can reduce Cd by approximately 40% per cited literature.
App: Cultivated Agaricus bisporus presents the lowest heavy-metal exposure risk among common commercial mushroom species. Wild Boletus species present highly variable Cd burdens; Boletus chrysenteron and Rozites caperatus should carry an elevated-Cd flag in any app model for wild mushroom ingredients.