Due to the Ozone Depletion humanity is facing more harmful rays from the sun. These rays cause severe health problems especially skin cancer. Skin cancer is one of the most widely spread cancer type in the world. 86% of skin cancer cases are caused by the harmful UV rays of the sun. The use of a product with an SPF protection factor of at least 15 all year reduces the risk of developing skin cancer by 50%. Skin cancer cases are also seen in Tanzania. 158 people died because of skin cancer.
What are the harms of UV A and UV B?
From the sun three different types of UV radiation reach to mother earth. These are UVA- UVB and UVC. Thanks to the ozone layer UVC is totally reflected and do not manage to reach the world surface, but part of UVB and almost all of UVA reaches to the surface. Both UVA and B causes skin cancer, UVA also causes early aging. One factor is important to keep in mind is the ozone depletion due to human factor. There is a gigantic hole on top of Antarctica where the ozone layer is too thin. This hole affects not only Antarctica but also the regions near to Antarctica. South America, Australia and Africa is the nearest continents to Antarctica so the effect of ozone hole will be more felt on these continents.
Why is Zanzibar/Tanzania or our region at more risk against those harms as compared to other regions?
Near the equator the solar ultra-violet radiation is at the highest level and having more than 8 hours of intense sunlight a day East Africa is one of the hottest regions in the World. Tanzania is in the low geographical attitudes where the UV radiation is highest (George A.Alexander, MD. Journal of the national medical association, Vol 75, No:8, 1983). According to WHO in 2020 Skin Cancer Deaths in Tanzania reached to 744 and 0.25% of the total deaths and ranks as number 22 in the world.
The UV exposure risk can be seen at the following graph where the yellow and red shows the highest UV radiation. As can be seen from the map Tanzania is on the highest risk zone.
How can we protect ourselves against the harmful effects of the sun radiations?
Of course, the main method of protection from the harmful UV rays is not to go outside especially at the noon where the UV radiation is highest. But this is not possible for many people. Especially farmers, fisherman where it is a must to work outside under the sun. The other methods are to use sun glasses to protect eyes, wearing hats, covering our skin with clothes and use sunscreens at the parts of our body which are open to UV radiation.
What do those numbers 30, 40, 45, 50 and 60 mean on bottles of Sunscreens?
These numbers are showing the Sun Protection Factor (SPF) of the sunscreen product.
Sun Protection Factor (SPF) is a method that measures how much sun protection products protect your skin against UVB rays alone. As SPF increases the protection against UVB radiation increases but the increase is not double for example for SPF 15 to SPF 30. The increase of protection fpr SPF 15 is 93%, for SPF 30 97%. So it is not so meaningful to go to very high SPF valued products. To be able to have high SPF the producers must put more UV filter into the product. This not only increases the cost of the product but also increases the toxicological risks as there are more chemicals in the product.