University of Saskatchewan, Canada. Professor Ekaterina Dadachova studies specimens of Cladosporium sphaerospermum, Cryptococcus neoformans, and Wangiella dermatitidis, three species of fungi collected from reactor number 4 of the Lenin nuclear power plant in Chernobyl, Ukraine, discovering their ability to grow faster in radiation-rich environments than other fungi. They possess large amounts of melanin, the pigment also found in our skin to protect it from solar radiation. Melanin is known for its ability to absorb light and dissipate ultraviolet radiation. This substance, abundant in fungi, converts nuclear radiation into chemical energy for their growth, perhaps similar to what happens in plants, which use chlorophyll to obtain energy in the process of photosynthesis. The fungi in question (Cladosporium sphaerospermum, Cryptococcus neoformans, and Wangiella dermatitidis) were exposed in the laboratory to radiation levels 500 times higher than background radiation, and were observed to proliferate much more vigorously and abundantly than at lower radiation levels. Therefore, black fungi exist, and are thriving in Chernobyl, attached to the most radioactive areas of reactor number 4. These fungi intrigued researchers as early as 1991, when they sent a remote-controlled robot into the eerie chambers of the abandoned Chernobyl nuclear power plant. They had already noticed the presence of various fungi growing on the reactor walls, apparently destroying the radioactive graphite. The fungi also seemed to grow toward sources of radiation, as if attracted to them. The good news is: life on Earth is very robust and can adapt to conditions considered prohibitive for humankind. The existence of bacteria that thrive in the vicinity of radioactive uranium was already known: Arthur W. Anderson discovered the bacterial species Deinococcus radiodurans in the 1950s during radiation sterilization sessions. This bacterium survives intense doses of radiation and even thrives inside nuclear reactors. Even the flora and fauna in the irradiated area around Chernobyl, after the initial radiation shock, have generally recovered and are even thriving, thanks largely to the absence of humans. But the discovery of melanin-rich fungi clinging to the highly radioactive reactor raises an intriguing possibility: there could be places in the universe colonized by melanin-rich organisms, capable of thriving in highly radioactive environments.
