Three species of fungi containing the black pigment melanin—a substance also present in human skin—grew larger and faster when exposed to high levels of radiation, even when deprived of nutrients.
A similar response was not seen in fungi lacking the pigment, as well as in fungi that did not receive the radiation exposure.
Researchers at Albert Einstein College of Medicine at New York's Yeshiva University were inspired by previous observations of enhanced fungus growth inside the destroyed Chernobyl nuclear reactor, after the Ukrainian facility exploded in 1986.
The team performed a series of experiments to test whether the fungi could be harvesting radiation to fuel their own growth, much like plants do when they capture solar energy through photosynthesis.
In addition to the faster fungal growth, the researchers noted changes in the electrical structure of the melanin exposed to radiation.
Lead researcher Ekaterina Dadachova said these observations suggest that the pigment may play a role similar to that of chlorophyll in plants, which traps energy from sunlight and converts it to “food energy“ needed to sustain life.
They later resettled unwilling participants on an island highly contaminated with radiation to learn how humans ingested and absorbed radiation in their environments