Some of the sun-worshipers out there believe that the use of sunscreens immediately guarantees protection against the most harmful rays. An investigation carried out by the Environmental Working Group showed recently that up to 80 percent of sunscreen lotions available on the market provide little or no protection at all and worse, they could even contain dangerous chemicals. If Neutrogena, Coppertone or Banana Boat rings any bells for you then you might have been exposed to unnecessary risks and these three companies are to blame.

The EWG report was received with severe criticism from both the three companies named above and dermatologists, although it does not attack some of the most controversial subjects regarding the use of sunscreens, such as whether they are capable of offering any protection at all, whether or not they can be replaced with protective clothing or why the safety standards regarding the use of sunscreens did not suffer any significant modification in more than three decades.

The light we see coming from the Sun is just a very narrow part of the electromagnetic spectrum, most of the other light wavelengths being filtered by Earth's atmosphere. However, some of them can penetrate all the way to ground level and among them there are two types of ultraviolet radiation known as UVA and UVB, both having dangerous effects on the health of our skin, and both capable of causing certain types of skin cancers. About 1 percent of all UV-triggered skin cancers eventually lead to the patient's death.

Since UVA penetrates deeper into the skin, it can be held responsible for the vast majority of skin cancer diseases and may in fact worsen the UVB induced effects.

The report points out that almost all sunscreens contain chemicals that break down in the sunlight, which is apparently the mechanism through which they protect the skin. However, the protection only lasts for about 15 minutes, while the manufacturers argue that it is effective for hours in a row. Other creams protect against UVA rays, albeit they contain harmful chemicals, such as oxybenzone which, in the sunlight, has a damaging effect on the DNA, thus can trigger the much feared degenerative disease.

Other previous studies even showed that people using sunscreens are at higher risk of contracting malignant melanoma, the deadliest type of skin cancer. This doesn't seem to be the case with zinc-based sunscreens though, the report found.