David, Norwich asked:
What were the repercussions of Chernobyl?
Chris - They have obviously isolated the area around Chernobyl and there are some real bad hotspots in there where if you go and take samples, you will find that plants and soil samples are very, very radioactive.
People have actually been in to have a look at the reactor buildings though and there was a very interesting paper, I think it was published in the journal PLoS One, a few years back and they found, bizarrely, a kind of fungus growing inside the remains of the nuclear reactor.
This fungus is very interesting because itís turned on lots of genes that make the pigment melanin, and melanin is the same stuff that makes us have brown skin and a sun tan. Itís there as a way of soaking up ionising radiation or energetic rays which could damage our DNA. By the yeast making itself very, very dark, it has its own in-built body armour against radiation and in this way, itís able to resist a lot of the insults of the radioactive environment.
This is one interesting example of, if you apply enormous selective pressure to nature then you can actually get some quite interesting things happening. And so, itís a really useful study area. Even though itís not necessarily a great thing to have happened, it gives us an insight into what can happen and how nature can respond in this sort of environment.
I guess the plants, Emily, must be doing some interesting things as well?
Emily - Itís true. So plants can actually incorporate radioactive isotopes into their bodies, so radioactive carbon-14 is actually used to study the plants and see how they distribute carbon around their bodies. So yes, the plants in that area would also be affected.
Chris - I suppose itís also worth mentioning, some scientists are looking at modifying plants to make them soak up some radioactive chemicals from the soil better and put them into insoluble forms so they get locked away in the plant and then you can clean up the soil by just harvesting the plants and destroying them. Basically, you get the components that are radioactive now in the plant. They're like a hover, sucking the things out of the soil, and itís a good way of cleaning up soil without having to cut soil away.
Emily - They are also looking at doing that for other toxic compounds. So if you've got lead in the soil, you can have a special type of currently slow growing plant, but they're working on that, and it takes up the lead and cleans up the soil.