In the summer after my freshman year of high school, I had a skin cancer scare. Actually, “scare” didn’t even describe it; I had convinced myself that I had skin cancer because of my tan from the summer and unnerving strings of Google searches. This “scare” made me very conscious of the time I spent in the sun. I would always wear sunscreen wherever I went, but at the time, naive and undereducated, I knew little about how things like that worked. I would ask questions like:
–Wait, so can the sun give people cancer? And can the world getting hotter lead to increased sun exposure?–
Skin cancer, oftentimes, is caused by overexposure to ultraviolet rays (UVR) from the sun. UV rays damage skin cells, which can cause sunburns and, over time, changes in skin texture, aging, and skin cancer. Environmental factors, like climate change, can amplify the impacts of UV rays. UV radiation is affected by changes in the stratospheric ozone and global climate change. Changes in the stratospheric ozone and climate over the years can alter the solar ultraviolet (UV) radiation conditions at the Earth’s surface. Decreased stratospheric ozone allows more UV rays to reach the Earth’s surface. Climate change modifies UV exposure and affects how people and ecosystems respond to these UV rays. Long periods of clear skies and recorded dry and warm conditions lead to unusually high UVI values. Such exceptional conditions are part of record-setting heat waves that affect large parts of the world and have been occurring more frequently in recent decades. Furthermore, rising temperatures due to climate change result in behavioral changes, such as increased time outdoors and less protective clothing that lead to more UV radiation exposure. These changes in human behavior in response to temperature increases increase the exposure humans have to UV rays, negatively impacting public health. Climate change modifies UV exposure, which affects how people and ecosystems respond to UV rays. These changes affect human health, ecosystem services, and food and water security.
The skin, the largest organ of the human body, protects us against physiological and molecular damage from the environment. The skin has profound capacities to undergo processes of regeneration to repair that damage. Deficiencies in the repair mechanisms of said damage caused by UV rays, genetically or non-genetically based, are linked to cellular stress and aging skin. UV rays are responsible for both the direct introduction of mutagenic changes to DNA and indirect effects executed by reactive oxygen species and photosensitizing reactions linked to the expression of the redox-sensitive signaling molecules. These molecules are involved in the induction of the biological responses in non-irradiated neighboring cells, including DNA mutagenesis and alterations in gene expression, as a result of the signals received from irradiated cells. The damage to genomic DNA can be linked to both direct and indirect exposure of a cell nucleus to radiation, which inevitably involves rapid as well as delayed biochemical responses to such exposure. This is an example of the biological bystander effect. The bystander effect refers to the biological response of one cell caused by an event in a nearby cell.
Such effects depend on intercellular communication and amplify the consequences of the original event. The biological relationship between irradiated and non-irradiated cells in the bystander effect demonstrates that irradiation of 1% of the cells, for example, can lead to corresponding DNA damage to over 30% of the cells. This effect is why protection from UV rays is important. UV rays have the capacity to change our genes and alter our DNA. This is also why climate mitigation is important. Mitigating and adapting to climate change can reduce the effects of UV rays.
So now, to answer the inquiries of little me, googling his life away, yes, exposure to UV rays from the skin can lead to skin damage and cancer over time. The world is getting hotter, and increased global temperatures can mean changes and alterations in the genome and DNA.
–But that doesn’t mean we are all doomed, does it?–
No, but it takes understanding the importance of skin protection, the dangers of UV rays, and the impacts of climate change on the planet and people to work towards a healthier future. A future where you and I can lay on the beach, protected from the sun and without fear of skin damage.
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The views and opinions expressed are those of the authors and do not necessarily reflect nor represent the Earth Chronicles and its editorial board.
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