Radiocesium Accumulation in Fungal Ecosystems

Radiocesium, principally isotopes 134Cs and 137Cs released by nuclear accidents and weapons testing, exhibits a strong affinity for fungal biomass. Fungi absorb radionuclides from soil and litter via hyphal networks, with mycorrhizal species often showing higher concentration factors than saprophytic ones. Within fruiting bodies, caps typically accumulate greater activity than stipes, reflecting differential element partitioning. The persistence of radiocesium in forest floor layers and its uptake by a diverse array of macrofungi underpin sustained internal exposure risks for wildlife and humans who consume wild mushrooms. Spatial heterogeneity in soil deposition, species‐specific uptake capacities and temporal declines in activity are key determinants of ecosystem contamination. Understanding fungal pathways informs ecological risk assessment and guides public health advisories. Moreover, insights into fungal radionuclide handling may advance bioremediation strategies aimed at reducing soil activity concentrations in contaminated landscapes worldwide.

Research from Nature Portfolio

One long-term study assessed radiocesium in wild mushrooms collected from a village within 30 km of a nuclear power station, revealing that over 90 % of specimens retained measurable 137Cs four years after the accident. Despite detectable levels, committed effective doses from typical annual consumption remained below public radiation limits, emphasising the value of ongoing monitoring to inform food safety. A complementary survey of local foods, including wild fungi, found that only a small fraction of plant and fungal samples exceeded regulatory thresholds. Internal dose estimates were acceptably low, yet the work highlighted the importance of risk communication and systematic follow-up to maintain public confidence during recovery phases.

Radiocesium Accumulation in Fungal Ecosystems publication trend

The graph below shows the total number of articles in radiocesium accumulation in fungal ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Radiocesium: Radioactive isotopes of caesium (134Cs, 137Cs) released by nuclear fission events, notable for environmental mobility and bioavailability.

Mycorrhizal species: Fungi that form mutualistic associations with plant roots, enhancing nutrient and radionuclide uptake via extensive hyphal networks.

Saprophytic species: Fungi that decompose dead organic matter, acquiring nutrients (and radionuclides) directly from litter and soil surfaces.

Bioaccumulation: The process by which organisms concentrate contaminants from their environment into their tissues over time.

Committed effective dose: The calculated radiation dose received by an individual over a defined period (usually 50 years for adults) following intake of a radionuclide.

References

1. Radiocesium concentrations in wild mushrooms after the accident at the Fukushima Daiichi Nuclear Power Station: Follow-up study in Kawauchi village. Scientific Reports (2017).
2. Concentrations of Radiocesium in Local Foods Collected in Kawauchi Village after the Accident at the Fukushima Dai-ichi Nuclear Power Station. Scientific Reports (2016).
3. Extensive analysis of radiocesium concentrations in wild mushrooms in eastern Japan affected by the Fukushima nuclear accident: Use of open accessible monitoring data. Environmental Pollution (2019).
4. Radioactive artificial 137Cs and natural 40K activity in 21 edible mushrooms of the genus Boletus species from SW China. Environmental Science and Pollution Research (2017).
5. Activities concentration of radiocesium in wild mushroom collected in Ukraine 30 years after the Chernobyl power plant accident. PeerJ (2018).