Current knowledge of the degradation products of tattoo pigments by sunlight, laser irradiation and metabolism: a systematic review.

The popularity of tattooing has increased significantly over recent years. This has raised concerns about the safety of tattoo inks and their metabolites/degradation products. The photolytic and metabolic degradation of tattoo pigments may result in the formation of toxic compounds, with unforeseen health risks. A systematic literature review was undertaken to determine the current state of knowledge of tattoo pigments' degradation products when irradiated with sunlight, laser light or metabolised. The review demonstrates that there is a lack of knowledge regarding tattoo pigment degradation/metabolism, with only eleven articles found pertaining to the photolysis of tattoo pigments and two articles on the metabolism of tattoo pigments. The limited research indicates that the photolysis of tattoo pigments could result in many toxic degradation products, including hydrogen cyanide and carcinogenic aromatic amines.