Mineral UV Filters: is often referred to inorganic UV filters (Zinc Oxide and Titanium dioxide) in sun protection products that form a physical shield on the skin surface to reflect the radiation.

Chemical UV Filters: this often refers to organic UV filters in sun protection products that form a chemical reaction to the UV radiation by taking it and converting to heat.

MYTH: "Chemical UV filters are more harmful to us and the environment because they will sink in."
FACT: "Both types of filters have the property to reflect the UV radiation on the surface, but will also be absorbed. However, the danger of this is not proven."

In reality, most UV filters already work immediately when applying as a shied for UV radiation and will slowly be absorbed. Both converts UV radiation to heat.

Mineral filters might reflect a little more UV rays on the surface, however, this is so minimal that it does not have to influence your choice. Old generations of chemical filters did have a bigger risk of irritations and allergies, but this is no longer the case with the newer generations.

Mineral filter advantage: can work like a tone up base on light skin tones because of the white cast.
Chemical filter advantage: no white cast and gives a higher UVA protection making it ideal for those with hyper pigmentations.

Both types of filters should be reapplied to the skin after a while as indicated on the packaging of the sunscreen product. This is not because the effect is reduced, but because the coverage is reduced by sweat, friction, etc.

Also there is actually not enough good evidence showing that our sunscreens are killing the coral reefs according to some coral researchers. The concentration of our sunscreens found on these corals are too low to have negative effect. However other things that we do as humans will have considerably impact on them such as overfishing, trampling while swimming near them, sewage system near civilisation, etc.

For the best UVA and UVB protection, we recommend to use a combination of both types of filters along with the correct and generous application!

A recent blog from Michelle van Labmuffin Science will tell you more about sunscreen myths.