Persistent dye staining of the skin rarely occurs in industry. When it does occur it presents three distinct problems. First, the mechanism of the staining must be studied to obtain some idea of the strength of the bonding or adherence of the dye to its substrate. Second, the anatomy and physiology of the substrate (the skin) must be considered. Third, the method of removal of the dye stain is important in order to keep skin damage to the minimum.
Buckley WR, West W. Persistent Dye Staining of the Skin. Arch Dermatol. 1970;102(1):71-77. doi:10.1001/archderm.1970.04000070073011