Safe by Design of nanomaterials in industrial production processes: nanomaterials in the cosmetic field

Cosmetic pleasantness of products containing inorganic UV filters depends on an unwanted whitening effect which is inversely correlated to their size. To overcome this effect, diameter has been reduced to nanosized but thus increasing the surface area and biological reactivity and carrying questions about the safety of humans and environment. Following a “safe and sustainability by design” approach, we designed a new class of optimized sunscreen UV filters by chemical functionalization of ZnO and TiO2 with Oxisol. If compared with the simple physical mixture, the new coated filters show different properties and benefits: a higher SPF (ISO 24443:2012), a better cytotoxic profile (MTT and NRU assay), a radical scavenging action (PCL assay) and an improved safety profile with a strong reduction of photocatalytic activity (Acid blue 9 test). In conclusion, our Safe by Design (acronym SbD) approach presents a new generation of UV filters bonded with booster molecules (by means of synergistic antioxidant effects) as the best compromise in the conscientious UV protection