Photodecomposition of Pigment Yellow 74, a Pigment Used in Tattoo Inks¶

Abstract

Tattooing has become a popular recreational practice among younger adults over the past decade. Although some of the pigments used in tattooing have been described, very little is known concerning the toxicology, phototoxicology or photochemistry of these pigments. Seven yellow tattoo inks were obtained from commercial sources and their pigments extracted, identified and quantitatively analyzed. The monoazo compound Pigment Yellow 74 (PY74; CI 11741) was found to be the major pigment in several of the tattoo inks. Solutions of commercial PY74 in tetrahydrofuran (THF) were deoxygenated using argon gas, and the photochemical reaction products were determined after exposure to simulated solar light generated by a filtered 6.5 kW xenon arc lamp. Spectrophotometric and high-pressure liquid chromatography (HPLC) analyses indicated that PY74 photodecomposed to multiple products that were isolated using a combination of silica chromatography and reversed-phase HPLC. Three of the major photodecomposition products were identified by nuclear magnetic resonance and mass spectrometry as N-(2-methoxyphenyl)-3-oxobutanamide (o-acetoacetanisidide), 2-(hydroxyimine)-N-(2-methoxyphenyl)-3-oxobutanamide and N,N''-bis(2-methoxyphenyl)urea. These results demonstrate that PY74 is not photostable in THF and that photochemical lysis occurs at several sites in PY74 including the hydrazone and amide groups. The data also suggest that the use of PY74 in tattoo inks could potentially result in the formation of photolysis products, resulting in toxicity at the tattoo site after irradiation with sunlight or more intense light sources.

Incidence of Health Problems Associated with Tattooed Skin: A Nation-Wide Survey in German-Speaking Countries

“…Five percent of the participants noticed a fading of the initial tattoo color (table 2). In case azo pigments are decomposed by any kind of radiation, hazardous products appear in skin, which has already been proven in vitro [30,31]. Besides coloring the skin, tattoo colorants are transported inside the body like medical drugs.…”

“…Such pigments can strongly absorb the ultraviolet part of solar radiation and are able to generate reactive oxygen species that might be responsible for those adverse skin reactions. At the same time, azo pigments can be decomposed to the corresponding hazardous aromatic amines [30,31]. …”

In situ chemical analysis of modern organic tattooing inks and pigments by micro‐Raman spectroscopy

“…Recently, some focus has shifted from identifying the organic pigments themselves to the products created by photodecomposition through laser or UV/sunlight exposure. Using a combination of HPLC, MS, UV/visible spectroscopy and proton nuclear magnetic resonance spectroscopy ( 1 H-NMR), specific organic pigments (monoazo Pigment Yellow 74 22 and naphthol AS Pigment Red 22 23 ) were found to be susceptible to cleavage by natural and simulated solar light and long-wave ultraviolet radiation into potentially toxic or carcinogenic aromatic amines. A recent survey 24 published in September 2006 revealed that almost 25% of people in the United States had one or more tattoos, with 17% of them having considered undergoing treatment to remove their tattoos.…”

Azoles and <i>bis</i>-Azoles: Synthesis and Biological Evaluation as Antimicrobial and Anti-cancer Agents

“…The 1 H-NMR spectra of the studied compounds showed signal in the region of δ= 13.72-14.42 ppm assignable to hydrazone proton (-CH= N-NH-). [26][27][28] Signal at δ= 5.27 29) ppm, which is characteristic for the CH protons of CH-azo form, was not detected. Also, IR spectra did not reveal broad signal at 3434 cm −1 , which is characteristic for OH of azo-enol form.…”