Many fungi have been isolated from the area around the destroyed Chernobyl Nuclear Power Plant, some of which have been observed directing their growth of hyphae toward radioactive graphite from the disaster, a phenomenon called “radiotropism”.
[3][4] Study has ruled out the presence of carbon as the resource attracting the fungal colonies, and in fact concluded that some fungi will preferentially grow in the direction of the source of beta and gamma ionizing radiation, but were not able to identify the biological mechanism behind this effect.
[5] While there are many cases of extremophiles (organisms that can live in severe conditions such as that of the radioactive power plant), a hypothetical radiotrophic fungus would grow because of the radiation, rather than in spite of it.
Examples of these environments include the Chernobyl Nuclear Power Plant, the International Space Station, and the Transantarctic Mountains.
It is hypothesized that radiotrophic fungi could potentially be used as a shield to protect against radiation,[2] specifically in affiliation to the use of astronauts in space or other atmospheres.
[2] The growth of this fungus and its ability to deflect the effects of ionizing radiation were studied for 30 days aboard the International Space Station.
[2] Estimations indicate that approximately a 21 cm thick layer could significantly deflect the annual amount of radiation received on Mars’ surface.
However as a viable substitute to reduce overall mass on potential Mars missions, a mixture with equal mole concentration of Martian soil, melanin, and a layer of fungi roughly 9 cm thick, could be used.