Coral trout killed by skin cancer – what happens when sun cream isn’t an option.

During my time at university one of the units I studied that I found was of most ‘practical’ value was “The History of Climate Change”. When I say practical value, I mean it taught me things that are and will be hugely beneficial to my understanding of the climate. One of the things I learnt about was the ozone layer and how human activities have contributed to ozone depletion. The ozone layer surrounds the Earth and is made up of molecules of O3. O3 molecules are not as stable as the O2 we breathe. This means O3 is highly reactive with other molecules such as halogens. How do halogens reach the ozone layer? During the 1980s CFCs (found in fridges and degreasing solvents) were the main cause and contributed significantly to ozone depletion. But why should we worry about ozone depletion?

The ozone protects us against harmful UV rays from our sun. As it depletes, more UV rays penetrate the Earth’s atmosphere and reach our skin. This can cause skin mutations, and potentially cases of skin cancer. For humans we can cope with extra UV ray exposure by applying more sun cream and keeping out of the sun, but what if you couldn’t access sun cream? What if you were an animal?

For animals, they don’t have the option to slap on some sun cream and in many cases they aren’t even able to find shade. Just as in humans, prolonged exposure to the sun’s harmful UV rays causes cancerous lesions to form on the skin of exposed animals.

The latest animal to be found with cancer is the coral trout of the Great Barrier Reef. A recent study carried out by representatives of the University of Newcastle found that 15% of sampled fish had cancerous lesions in their skin. This finding is significant because it is the first recorded case of cancer in wild fish. If the coral trout is susceptible to cancer, it stands to reason other fish species could be at risk. The implications of that throughout the ecosystem would be phenomenal, to humans as well other species reliant on fish for their survival.

Coral trout - a) unaffected b) affected
Coral trout - a) unaffected b) affected

Researchers at the University of Newcastle have stated the most likely explanation for the cancer is the hole in the ozone layer, which increases radiation in this region. The solution is therefore not to just ‘slap on some sun cream’ but to deal with the issue at hand. Through international agreements such as the Montreal Protocol, compounds that damage the ozone are beginning to be removed from the atmosphere. Scientists predict that through such measures the ozone will begin to recover by 2024, with recovery to pre-1980s levels by 2068. But only by the public continually putting pressure on policy makers, will this goal be achieved. So next time you take to a sun lounger, with a sun hat, sun glasses and sun cream, consider the comparatively defenceless coral trout.