Filters used in sunscreens have been found to penetrate deep into the skin and acting together with UV radiation cause damage below the surface.
Once found themselves deep under, they generate some harmful compounds, which attack the skin cells.

Although they could do a very good job protecting the skin, the lotions need to be applied correctly-uniformly and continuously.

However, not all consumers read the instructions and they need protection too. This is why the manufacturers are being pushed to develop new creams that will not soak so deep into the skin. This study shows that the sunscreen and UV lights act together to cause damage to the skin cells. What causes the damage is ROS, reactive oxygen species, that is being produced by the skin when exposed to the UV rays. Three sunscreen filters have been found to generate ROS in skin when exposed to ultraviolet radiation, increasing their levels. If sunscreen is not applied continually to prevent the UV rays from penetrating in the skin and reaching the filters, damage will occur.

Health experts also warn that sunscreens shouldn’t be rubbed into the skin as they offer no protection that way. It is as if there was no cream at all. The only way to avoid the skin’s damage caused by the sun and the filters is to apply thick layers of creams on the skin and to do it frequently.