If Not Applied Appropriately During Sunbaths, Sunscreens Can Damage the Skin

Everyone knows that sunscreens are a must when it comes to sun exposure. It does not matter if you are fairer or darker skinned, blond or brunette, everyone should use sunscreens when lying on the beach under the caressing rays of the sun. However, as idyllic this may sound or be, we should all be aware of the fact that all sun rays are laden with ultraviolet (UV) radiation which harms the unprotected skin and may lead to serious skin problems and even skin cancer.

A recent study conducted by researchers at the University of California, Riverside, shows that when sunscreens are not applied appropriately on the skin, the filters in these healthcare products penetrate all the layers of the skin and attack both epidermis and dermis cells.


The skin consists of two main layers: the epidermis and the dermis. The epidermis is the layer found on the outer side of the skin that acts as a barrier against possibly exterior harmful agents. The dermis is placed on the inner side of the skin and it contains all the "ingredients" of this organ: nerves, hair follicles, sweat glands etc.

The cells and tissues of our skin perform the main role of protecting our body against the exterior harmful agents and factors. Besides this, it has several other roles such as offering a base for the hair follicles that allow hair growth (hair also provides protection against outer agents) and permitting the body to release the toxins through perspiration. The skin also helps regulating the body's temperature and the amount of water in the body, controls the infections etc.

If people taking sunbaths do not apply repeatedly sunscreens throughout all their bodies, it will allow UV radiation to penetrate their skin and cause severe disorder.

Sun rays are divided into three categories that have different effects upon our body: UVA, UVB and UVC rays. Therefore, the ultraviolet (UV) radiation is of A, B and C type. Out of these, only UVA and UVB types are harmful to our skin, damaging its surface and inner structure when taking prolonged sunbaths. This happens because the third type, the UVC radiation, does not penetrate the atmosphere's ozone layer and does not reach Earth.

However, UVB and UVA act differently upon our skin and do not equally damage it. The UVB rays are mostly responsible for most cases of sunburn, as they are shorter than UVA rays and only reach the surface of the skin that is made up of the epidermis layer. The UVB radiation is absorbed by the stratum corneum on the epidermis surface. This stratum corneum is the dead cells layer - the visible layer of the skin. The UVA radiation is partly absorbed and blocked by the ozone layer before reaching Earth.

Besides that fact that an inappropriate use of sunscreens during sun exposure lets harmful UV radiation pierce the skin, scientists showed that filter particles in sunscreens also penetrate the skin and can attack skin cells. This is why they called for more professional sunscreens with filter molecules which keep to the surface of the skin and do not go beyond the dead cells layer of the epidermis.

"Sunscreens do an excellent job protecting against sunburn when used correctly. This means using a sunscreen with a high sun protection factor and applying it uniformly on the skin. Our data show, however, that if coverage at the skin surface is low, the UV filters in sunscreens that have penetrated into the epidermis can potentially do more harm than good. More advanced sunscreens that ensure that the UV-filters stay on the skin surface are needed; such filters would reduce the level of UV-induced ROS. Another solution may be to mix the UV-filters with antioxidants since antioxidants have been shown to reduce UV-induced ROS levels in the skin," explains Kerry M. Hanson, lead researcher of the study and a senior research scientist in the Department of Chemistry at the University of California, Riverside.