The proposed technology is about the development of an innovative sunscreen obtained from cod fish bones, according to the principles of the circular economy. The sunscreen is a reddish powder, which is constituted of hydroxyapatite (a calcium phosphate main component of human bones) modified with iron. It is prepared with a simple and easily scalable process (treatment of the bones in Fe solution and successively at T = 700 oC) and could be adapted for bones of other fishes.
The powder absorbed the UV radiation in the whole range and it kept this property when incorporated into a cream. For this performance the sunscreen could be classified as 5 stars (maximum) according to the Boots classification system. The Sun Protection Factor (SPF) of the cream, however, was lower than for a commercial inorganic sunscreen.
The powder was incorporated into chitosan, a material used in biomedicine; the composites showed antibacterial and UV-protection properties, suitable for wound dressing.
One advantage of this sunscreen is its non-toxicity; it is in fact made of is hydroxyapatite, a compound already present in our body (main component in human bones).
This product is also not harmful for the environment (marine waters) because, differently from other inorganic sunscreens (TiO2, ZnO), is not photocatalytic, i.e. it does not generate free radicals when irradiated. The accumulation in the environment of photocatalytic sunscreens is a cause of growing concern.
The sunscreen is produced from by-products of the food industry; overall its impact on the environment is lower than other commercial sunscreens.
This sunscreen can also be employed in combination with other sunscreens, to have a synergistic effect.
The particles of the powder are > 100 nm; this is an advantage as new EU regulations make compulsory to indicate on the label when smaller particles are used (smaller particles are not well accepted by the consumers).
Italy, Europe, USA.