Determination of the Phototoxicity Potential of Commercially Available Tattoo Inks Using the 3T3-neutral Red Uptake Phototoxicity Test

Abstract

Tattooing is an ancient practice and its popularity has been increasing in the recent years. After tattooing, complications may occur related to compose tattoo inks. In this study, the phototoxicity potential of the blue, red and black colors of the most commonly used three different commercially-available tattoo ink brands have been examined by performing in vitro 3T3-neutral red uptake (NRU) phototoxicity test. In the study, the phototoxicity of serial diluted concentrations of tattoo inks were evaluated with in vitro 3T3-NRU phototoxicity test method according to OECD guide 432. The data obtained from the NRU test result were uploaded to Phototox software (version 2.0) and the phototoxicity potentials of tattoo inks were determined via the calculation of the mean photo effect (MPE) and photo irritation factor (PIF) values. The red, black and blue colors of three different commercially available tattoo inks did not cause a cytotoxic activity on BALB/c 3T3 cells with 3T3-NRU test. The IC50 values could not be determined +ultraviolet (UV) and -UV conditions. PIF values could not be calculated and MPE values were <0.1, which predicts the absence of phototoxic effect for all of the tested tattoo inks. All tested inks were evaluated as non-phototoxic according to the results of MPE values calculated using Phototox software. However, test results should be verified by other phototoxicity test methods to obtain a comprehensive evaluation of phototoxic complications of different tattoo inks.