Table 1.

Search strategy.

Databases	Keywords
PubMed	(“3d skin model”[tiab] OR “reconstructed human skin model”[tiab] OR “human skin model”[tiab] OR “epidermis model”[tiab] OR “episkin”[tiab] OR “epidermis”[tiab] OR “skin equivalent model”[tiab] OR “reconstructed human epidermis”[tiab]) AND (“titanium dioxide”[tiab] OR “tio2”[tiab] OR “titanium”[tiab] OR “titanium”[mesh]) AND (“nanoparticles”[tiab] OR “NP”[tiab] OR “nanomaterials”[tiab] OR “nanoparticles”[Mesh] OR “metal nanoparticles”[mesh]) AND (“skin corrosion”[tiab] OR skin “irritation”[tiab] OR “toxicity”[tiab] OR “cytotoxicity”[tiab] OR “phototoxicity”[tiab] OR “irritation”[tiab] OR “corrosion”[tiab] OR “Skin Irritancy Tests”[Mesh])
Science Direct	(“skin model” OR epidermis OR episkin OR “skin equivalent model” OR “reconstructed human epidermis”) AND (titanium OR tiO2) AND (nano*) AND (corrosion OR irritation OR toxicity OR cytotoxicity OR phototoxicity)
Web of science	(“skin model” OR “epidermis model” OR “episkin” OR “skin equivalent model” OR “reconstructed human epidermis”) AND (“tio2” OR “titanium”) AND (“nanoparticles” OR “NP” OR “nanomaterials”) AND (“skin corrosion” OR “skin irritation” OR “toxicity” OR “cytotoxicity” OR “phototoxicity” OR “irritation” OR “corrosion”)
Scopus	(“skin model” OR “epidermis model” OR “episkin” OR “epidermis” OR “skin equivalent model” OR “reconstructed human epidermis”) AND (“tio2” OR “titanium”) AND (“nano*”) AND (“toxicity” OR “citotoxicity” OR “phototoxicity” OR “irritation” OR “corrosion”)
Scielo	(“skin model” OR “epidermis model” OR “episkin” OR “epidermis” OR “skin equivalent model” OR “reconstructed human epidermis”) AND (“tio2” OR “titanium”) AND (“nano*”) AND (“toxicity” OR “citotoxicity” OR “phototoxicity” OR “irritation” OR “corrosion”)
Gray Literature	(skin OR epidermis) AND (titanium OR tio2) AND (skin irritancy test OR *toxicity)