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

Applicability of In Silico New Approach Methods for the Risk Assessment of Tattoo Ink Ingredients

Tattoo inks contain several substances, including organic and inorganic pigments, additives, and solvents, which may pose a health risk to not only the tattooed skin but also to other parts of the human body due to intradermal exposure. Substances in tattoo inks are regulated by entry 75 in Annex XVII of REACH Regulation (EC) No. 1907/2006. However, despite these legal requirements, a well-defined criterion for the safety assessment of tattoo inks remains lacking. In this context, 2021 BfR opinion titled "Tattoo inks: minimum requirements and test methods" proposed a comprehensive risk assessment of pigments using in vitro/in-chemico data in accordance with OECD Guidelines and CLP Regulations. In the absence of experimental data, new approach methodologies (NAMs) may be used for data-gap filling. Therefore, this work evaluates the applicability of in silico NAMs for data-gap filling for a list of tattoo ink ingredients identified by the Joint Research Centre (JRC) and BfR for genotoxicity assessment. Experimental in vitro genotoxicity data were acquired from the International Uniform Chemical Information Database (IUCLID) which makes non-confidential REACH Study Results publicly accessible. The specific aims of this analysis were the evaluation of in silico genotoxicity predictions from publicly available QSAR tools and structural alerts, the development and validation of new QSAR models specific to tattoo ink ingredients, and the application of in silico models for categorization and prioritization of data-poor ingredients for further screening. Based on the workflow developed in this study, 4 high priority, 18 medium priority, and 2 low priority substances were identified for further assessment.

Melanoma Arising in Tattoos: A Case Series and Scoping Review of the Literature

BACKGROUND/OBJECTIVES

The prevalence of tattoos has risen globally in recent decades, ranging from 10% to 29%. Although rare, melanomas arising within tattoos are challenging for dermatologists due to the complexities in clinical and dermoscopic evaluation. In this article, we report two cases of melanoma on tattoos, review the reported cases in the literature, and examine the role of reflectance confocal microscopy (RCM) in improving the diagnosis of melanoma on tattooed skin.

METHODS

We conducted a systematic literature search on Medline/Pubmed for the period from the inception of the databases to 31 October 2024, using the Mesh major topics 'melanoma' AND 'tattoo' OR 'tattoo skin tumor'. Out of the 268 citations identified by our search, 37 studies met the eligibility criteria.

RESULTS

In total, 43 cases of melanoma arising on tattooed skin were identified, to which we add our 2 cases, bringing the total to 45. The most common locations were the upper limbs (53%) and trunk (38%), predominantly arisen on black and blue tattoos. Of 40 cases with known depth of invasion, 4 were in situ and 36 invasive, with a mean Breslow thickness of 2.7 mm. Seven patients had a positive sentinel lymph node. Of 16 cases with an available horizontal diameter, 12 melanomas had a diameter of ≥1 cm.

CONCLUSIONS

The limited cases of ''melanoma on tattoos" reported in the literature suggest a coincidental association rather than a direct causal link. Nevertheless, increased awareness among patients and tattoo artists about potential risks and preventive measures may enhance the management of melanocytic lesions in tattooed individuals. Lastly, integrating reflectance confocal microscopy with dermoscopy increases the overall diagnostic accuracy for melanoma, enhancing the identification of pigmented and non-pigmented skin lesions.

Accelerated aging modulates the toxicological properties of the diazo tattoo pigment PO13

Pigment particles used in tattooing may exert long terms effect by releasing diffusible degradation products. In the present work, aqueous suspensions of the organic orange diazo pigment PO13 were aged by exposure to simulated sunlight at 40 °C. The morphology and the surface charge of PO13 particles were barely modified upon aging, but primary particles were released by de-agglomeration. Soluble photoproducts were detected in the liquid fractions. One of this photoproduct (DCBP) was produced in large amount in suspension in isopropanol and purified. The toxicological profiles of aged suspensions, their soluble fractions and DCBP were then determined on the keratinocyte cell line HaCaT. Impact of suspensions of PO13 on viability was hardly affected by aging. In contrast, the soluble fractions were more toxic after photo-aging. Suspensions and filtrates induced neither release of reactive oxygen species nor formation of DNA strand breaks. The samples exhibited only limited effects on the proteome of HaCaT cells. Conversely, DCBP was cytotoxic and induced the production of ROS, but was not genotoxic. DCBP was found to activate CYP450 monooxygenases known to be involved in the metabolism of xenobiotics. Altogether, our results show that aging of PO13 leads to the release of toxic soluble compounds.

Identification of the pigments used in permanent makeup and their ability to elicit allergic contact dermatitis

BACKGROUND

Decorative tattoos are known to contain ingredients that may elicit allergic contact dermatitis; it is less well-known if permanent makeup pigments carry the same risk.

OBJECTIVE

Identify pigments used in permanent makeup inks sold in the United States and review cases of allergic contact dermatitis to these pigments.

METHODS

Using internet searches, permanent makeup inks sold in the United States were identified. Safety data sheets were used to catalog pigments used in permanent makeup. A subsequent literature search was performed to identify cases of allergic contact dermatitis to these pigments.

RESULTS

A total of 974 permanent makeup inks were reviewed, and 79 unique pigments were identified. The average product contained 4 pigments. Twenty of the pigments were inorganic metals, including carbon, iron, chromium, manganese, and molybdenum. Fifty-nine pigments were organic, of which most were azo, quinacridone, or anthraquinone dyes. A literature search revealed that 10 of the 79 pigments were associated with allergic contact dermatitis.

CONCLUSION

Permanent makeup primarily uses organic pigments, although some metallic pigments are still used. Physicians should also be aware that some of these pigments-both organic and inorganic-are known causes of allergic contact dermatitis. Of note, patch testing to these ingredients can be negative.

Biodistribution of iron oxide tattoo pigment: An experimental murine study

Tattoo pigment is expected to migrate beyond the skin to regional lymph nodes and the liver. Modern tattoo ink commonly contains metals that may pose a clinical problem during MRI examinations. This study aimed to investigate the biodistribution of iron oxide pigment to internal organs in mice. Moreover, when exposed to a static magnetic field, we studied whether any reactions followed in the tattooed skin. Twenty-seven hairless C3.Cg-Hrhr/TifBomTac mice were included; 20 were tattooed with iron oxide ink in a rectangular 3 cm2 pattern; seven were controls. Ten of the tattooed mice were exposed to a 3 T MRI scanner's static magnetic field. Following euthanasia, evaluations of dissected organs involved MRI T2*-mapping, light microscopy (LM) and metal analysis. T2*-mapping measures the relaxation times of hydrogen nuclei in water and fat, which may be affected by neighbouring ferrimagnetic particles, thus enabling the detection of iron oxide particles in organs. Elemental analysis detected a significant level of metals in the tattooed skin compared to controls, but no skin reactions occurred when exposed to a 3 T static magnetic field. No disparity was observed in the liver samples with metal analysis. T2* mapping found no significant difference between the two groups. Only minute clusters of pigment particles were observed in the liver by LM. Our results demonstrate a minimal systemic distribution of the iron oxide pigments to the liver, whereas the kidney and brain were unaffected. The static magnetic field did not trigger skin reactions in magnetic tattoos but may induce image artefacts during MRI.

Hypersensitivity to permanent tattoos: Literature summary and comprehensive review of patch tested tattoo patients 1997-2022

We outline constituents of tattoo and permanent make-up ink with regard to inflammatory tattoo reactions and population-based confounders. The comprehensive review of patch-tested tattoo patients between 1997 and 2022 shows that tattoo allergy cannot be reliably diagnosed via patch testing with today's knowledge. Weak penetration and slow haptenization of pigments, unavailability of pigments as test allergens and a lack of knowledge concerning relevant epitopes hamper the diagnosis of tattoo allergy. Patch testing p-phenylenediamine and disperse (textile) dyes is not able to close this gap. Sensitization to metals was associated with all types of tattoo complications, although often not clinically relevant for the tattoo reaction. Binders and industrial biocides are frequently missing on ink declarations and should be patch tested. The pigment carbon black (C.I. 77266) is no skin sensitizer. Patch tests with culprit inks were usually positive with cheap ink products for non-professional use or with professionally used inks in patients with eczematous reactions characterized by papules and infiltration. Tape stripping before patch testing and patch test readings on Day 8 or 10 may improve the diagnostic quality. The meaningfulness of the categorical EU-wide ban of Pigment Green 7 and Pigment Blue 15:3 is not substantiated by the presented data.

Solar photodegradation of irinotecan in water: optimization and robustness studies by experimental design

Irinotecan, a widely prescribed anticancer drug, is an emerging contaminant of concern that has been detected in various aquatic environments due to ineffective removal by traditional wastewater treatment systems. Solar photodegradation is a viable approach that can effectively eradicate the drug from aqueous systems. In this study, we used the design of experiment (DOE) approach to explore the robustness of irinotecan photodegradation under simulated solar irradiation. A full factorial design, including a star design, was applied to study the effects of three parameters: initial concentration of irinotecan (1.0-9.0 mg/L), pH (5.0-9.0), and irradiance (450-750 W/m²). A high-performance liquid chromatography coupled with a high-resolution mass spectrometry (HPLC-HRMS) system was used to determine irinotecan and identify transformation products. The photodegradation of irinotecan followed a pseudo-first order kinetics. In the best-fitted linear model determined by the stepwise model fitting approach, pH was found to have about 100-fold greater effect than either irinotecan concentration or solar irradiance. Under optimal conditions (irradiance of 750 W/m², 1.0 mg/L irinotecan concentration, and pH 9.0), more than 98% of irinotecan was degraded in 60 min. With respect to irradiance and irinotecan concentration, the degradation process was robust in the studied range, implying that it may be effectively applied in locations and/or seasons with solar irradiance as low as 450 W/m². However, pH needs to be strictly controlled and kept between 7.0 and 9.0 to maintain the degradation process robust. Considerations about the behavior of degradation products were also drawn.

When Body Art Goes Awry-Severe Systemic Allergic Reaction to Red Ink Tattoo Requiring Surgical Treatment

The aim of this report is to present a case of a patient who developed unusual systemic hypersensitivity reaction to a red-pigmented tattoo and to discuss diagnostic difficulties in case of systemic reactions to tattoo ink. The patient reported erythroderma on his arms and chest accompanied by plaque elevation of red parts of his most recently performed forearm tattoo as his primary symptoms. His health condition entailed a prolonged topical and intravenous immunosuppressive therapy, which proved ineffective. Over a year after emergence of initial symptoms, he presented to the Plastic Surgery Clinic with generalized erythroderma, systemic lymphadenopathy, elevation and granuloma formation in red tattoos on his forearm and complaints of fatigue and inability to participate fully in work-related and social activities. The patient underwent six staged excisions with direct closures, flap plasties and full-thickness skin grafts. Following completion of each surgical resection, the patient's symptoms gradually subsided. We find this case illustrative of a clinical challenge that delayed hypersensitivity reactions to red tattoos may pose. Furthermore, we provide insights on management of hypersensitivity reactions. This report underlines the importance of social awareness of and public health approach to tattoo complications as key to successful prevention, identification and treatment of adverse reactions to tattoos.

In Vivo Visualization of Tattoo Particles Using Multiphoton Tomography and Fluorescence Lifetime Imaging

With increased popularity of decorative tattoos, awareness of tattoo-based dermatological complications has been raised. Health issues include a broad spectrum dominated by allergies and infections. To examine the etiopathology and prognose the outcome of an appropriate therapy, a non-invasive intravital diagnostic approach is indicated. The present pilot study introduces multiphoton tomography equipped with fluorescence lifetime imaging as a diagnostic technique to examine the morphological and metabolic status of tattooed human skin at patient's bedside. The distributing course of tattoo particles can be visualized over time. By providing optical biopsies, inflammation-based alterations in freshly tattooed skin and tattoo complications can be analyzed. The study concludes that multiphoton tomography combined with fluorescence lifetime imaging is a suitable technique for in vivo visualization of tattoo pigments as well as for the assessment of quantitative and qualitative skin changes after injection of tattoo ink into human skin.

“For Asia Market Only”: A Green Tattoo Ink between Safety and Regulations

Due to the increasing tattoo practicing in Eastern countries and general concern on tattoo ink composition and safety, the green tattoo inks Green Concentrate by Eternal, for European and “for Asia Market Only” were analyzed, under the premise that only the former falls under a composition regulation. A separation of the additives from the pigment was carried out by successive extraction in solvents of different polarities, i.e., water, acetone and dichloromethane. The solid residues were analyzed by IR and Raman spectroscopies, the liquid fractions by GC/mass spectrometry. The relative pigment load and element traces were also estimated. We found that the European and the Asian inks are based on the same pigment, PG7, restricted in Europe, though at different loads. They have a similar content of harmful impurities, such as Ni, As, Cd and Sb and both contain siloxanes, including harmful D4. Furthermore, they have different physical-chemical properties, the European ink being more hydrophilic, the Asian more hydrophobic. Additionally, the Asian ink contains harmful additives for the solubilization of hydrophobic matrices and by-products of the phthalocyanine synthesis. Teratogenic phthalates are present as well as chlorinated teratogenic and carcinogenic compounds usually associated to the laser treatment for removal purposes, to a larger extent in the European ink. The composition of the inks does not seem to reflect regulatory restrictions, where issued.