Tattoos - more than just colored skin? Searching for tattoo allergens

Detection of anaerobic and aerobic bacteria from commercial tattoo and permanent makeup inks

Tattooing and use of permanent makeup (PMU) have dramatically increased over the last decade, with a concomitant increase in ink-related infections. Studies have shown evidence that commercial tattoo and PMU inks are frequently contaminated with pathogenic microorganisms. Considering that tattoo inks are placed into the dermal layer of the skin where anaerobic bacteria can thrive and cause infections in low-oxygen environments, the prevalence of anaerobic and aerobic bacteria should be assessed in tattoo and PMU inks. In this study, we tested 75 tattoo and PMU inks using the analytical methods described in the FDA Bacteriological Analytical Manual Chapter 23 for the detection of both aerobic and anaerobic bacterial contamination, followed by 16S rRNA gene sequencing for microbial identification. Of 75 ink samples, we found 26 contaminated samples with 34 bacterial isolates taxonomically classified into 14 genera and 22 species. Among the 34 bacterial isolates, 19 were identified as possibly pathogenic bacterial strains. Two species, namely Cutibacterium acnes (four strains) and Staphylococcus epidermidis (two strains) were isolated under anaerobic conditions. Two possibly pathogenic bacterial strains, Staphylococcus saprophyticus and C. acnes, were isolated together from the same ink samples (n = 2), indicating that tattoo and PMU inks can contain both aerobic (S. saprophyticus) and anaerobic bacteria (C. acnes). No significant association was found between sterility claims on the ink label and the absence of bacterial contamination. The results indicate that tattoo and PMU inks can also contain anaerobic bacteria.

IMPORTANCE

The rising popularity of tattooing and permanent makeup (PMU) has led to increased reports of ink-related infections. This study is the first to investigate the presence of both aerobic and anaerobic bacteria in commercial tattoo and PMU inks under aerobic and anaerobic conditions. Our findings reveal that unopened and sealed tattoo inks can harbor anaerobic bacteria, known to thrive in low-oxygen environments, such as the dermal layer of the skin, alongside aerobic bacteria. This suggests that contaminated tattoo inks could be a source of infection from both types of bacteria. The results emphasize the importance of monitoring these products for both aerobic and anaerobic bacteria, including possibly pathogenic microorganisms.

Lessons learned in a decade: Medical-toxicological view of tattooing

Tattooing has been part of the human culture for thousands of years, yet only in the past decades has it entered the mainstream of the society. With the rise in popularity, tattoos also gained attention among researchers, with the aim to better understand the health risks posed by their application. 'A medical-toxicological view of tattooing'-a work published in The Lancet almost a decade ago, resulted from the international collaboration of various experts in the field. Since then, much understanding has been achieved regarding adverse effects, treatment of complications, as well as their regulation for improving public health. Yet major knowledge gaps remain. This review article results from the Second International Conference on Tattoo Safety hosted by the German Federal Institute for Risk Assessment (BfR) and provides a glimpse from the medical-toxicological perspective, regulatory strategies and advances in the analysis of tattoo inks.

Tattoo inks: evaluation of cellular responses and analysis of some trace metals

After tattoo application, inks remain in the skin, mostly in the dermal layer, and manufacturers use inks that have not been adequately evaluated for safety in tattoo production. In this study, the metal contents (Cd, Hg, Pb, and Cr) of tattoo inks available in the Turkish market were determined and the relationship between cell viability and inflammatory response of the detected metal levels was investigated. Nine tattoo inks (3 colors) from 3 different brands abbreviated as E, I, and W were examined. ICP-MS was used for element analysis. The viability of human keratinocyte cells was determined by the WST-1 assay following ink exposures at various dilutions. IL-18 levels were measured in cell culture supernatant by ELISA method following ink or metal (Cd, Cr, Hg, and Pb) exposures. The concentrations of trace elements were found in inks as follows: Cd, 0.0641-1.3857; Hg, 0.0204-0.2675; Pb, 0.8527-6.5981; Cr, 0.1731-45.3962 µg mL-1. It was observed that the levels of Pb and especially Cr in the samples exceeded the limit values. Tattoo inks reduced the cell viability in a dose- and color-dependent manner. IL-18 release was significantly increased in all groups except Cr and black ink of brand I treated cells (p < 0.05). Our results show that the metal contents of tattoo inks exceed Council of Europe Resolution values in some samples and some inks induce immune system activation (IL-18 secretion) and cytotoxic effects. It is thought that these findings may contribute to the toxic/adverse effects of tattoo inks commonly used.

Cutaneous Adverse Reactions Associated with Tattoos and Permanent Makeup Pigments

Tattooing is the procedure of implanting permanent pigment granules and additives into the dermal layer of the skin, serving various purposes such as decoration, medical identification, or accidental markings. There has been a significant rise in the popularity of decorative tattooing as a form of body art among both teenagers and young adults. Thus, the incidence of tattoos is increasing, with expanding applications such as permanent makeup, scar camouflage, nipple-areola, lips, and eyebrows tattooing, and utilization in oncological radiotherapy such as colon marking. However, there have been reported a broad range of adverse reactions linked to tattooing, encompassing allergic reactions, superficial and deep cutaneous infections, autoimmune disorders induced by the Koebner phenomenon, cutaneous tumors, and others. These reactions exhibit different onset times for symptoms, ranging from immediate manifestations after tattoo application to symptoms emerging several years later. Given the limited information on a tattoo's side effects, this review aims to elucidate the clinical spectrum of cutaneous complications of tattoos in different patients. The analysis will investigate both allergic and nonallergic clinical presentations of tattoo-related side effects, microscopic findings from skin biopsies, and therapeutic outcomes. This exploration is essential to improve our understanding of tattoo-related cutaneous complications and associated differential diagnoses and highlight the significance of patient awareness regarding potential risks before getting a tattoo.

Immune Response in Laser Tattoo Removal: A Systematic Review

Introduction: The immune response to laser tattoo removal poses a significant challenge in its management, primarily due to its unpredictable nature, which can range from mild hypersensitivity reactions to severe anaphylaxis. Such responses can potentially hinder the effectiveness of laser tattoo removal procedures. Therefore, gaining a comprehensive understanding of the immune response to tattoo removal using laser techniques is of utmost importance to develop more efficient management strategies. This study aims to address this need by analyzing eight carefully selected articles obtained through a thorough literature review. Methods: To explore the immune response associated with laser techniques in tattoo removal, we employed a rigorous research methodology. A thorough literature review was conducted using reputable search engines such as Google Scholar, SagePub, and PubMed to collect relevant articles. Initially, 788 potential articles were identified through this process. Following meticulous scrutiny, only eight articles that met stringent inclusion criteria were selected for our study. This meticulous selection process ensures that the information presented here is derived from high-quality and pertinent research. Results: Based on the analysis of the eight selected articles, our findings illuminate the various immune responses that emerge following tattoo removal using laser techniques. These responses include hypersensitivity reactions, allergic manifestations, and, in certain instances, anaphylaxis. Hypersensitivity reactions typically manifested as erythema, edema, and pruritus, while allergic responses were observed in the form of urticaria. In summary, our study highlights that the immune response to laser tattoo removal primarily elicits hypersensitivity and, in some cases, anaphylaxis reactions. Conclusion: Our study underscores the significance of clinicians being vigilant regarding potential immune responses during laser tattoo removal. It is crucial to closely monitor patients to promptly address any adverse reactions. Further research holds the potential to enhance our understanding, paving the way for improved management strategies that can enhance patient safety and treatment success.

Types of colourants used in tattoo and permanent make-up techniques, legal regulations, health, and psychological aspects of tattooing

Background

It is estimated that more than 60 million people in Europe, that is, around 12% of the European population, have at least one tattoo. However, there is still little information on the long-term effects of tattoos. Inks used for tattooing are a mixture of chemicals, with pigments being the main components responsible for the visual effect. The pigments used are not produced specifically as ingredients for tattooing, but mainly/primarily for the needs of industry, where lower purity requirements and quality standards are acceptable. It is therefore necessary to understand the risks associated with tattoos, but also to implement appropriate legal regulations. The aim of this article was to collect and summarise the results of research conducted so far on the type of colourants used in tattoo ink and to analyze the impact of these on human health. In addition, as part of this work, the current legal acts regulating the concentration limits and composition of inks used in tattooing as well as the psychological aspects of tattooing were collected and presented.

Methods

Scientific reports and articles from renowned journals from 1994 to 2022, relevant review and research publications in PubMed, and Google Scholar were analyzed. To analyze the available research literature, the Web of Science, Scopus, PubMed databases were used. The following keywords were used to search for publications: tattoos, colourants used in tattoos, side effects of tattoos, legal acts, psychological aspects of tattoos.

Results

The result of the literature analysis indicates a risk to health and side effects associated with tattooing the body. There are still no standardised test methods to analyze tattoo inks and assess their safety. Although the art of tattooing has been known for millennia, European legal authorities have not yet implemented effective regulations. Currently, tattoo products in Europe are covered by the general REACH regulation (Resolution ResAP, 2008; EU regulation 2020/2081, 2020). on product safety. The new amendment in force since January 4, 2022 introduces concentration limits for certain substances used in tattoo and permanent makeup inks. However, these provisions do not sufficiently protect either the consumer or the tattoo industry.

Conclusions

The results of the research indicate a potentially harmful effect on skin health. A more stringent safety assessment of the colourants used for tattooing is recommended, supported by studies and applicable legislation.

[Useful knowledge regarding tattoos]

The number of people with tattoos has continued to increase in recent years. In the USA about 23% and in Europe 9-12% of the population have tattoos. In the German media (2019) and by the infoportal Statista (2017), it is assumed that 21-25% of citizens have tattoos and that the trend is increasing (Statista 2018: 36%). Men and women wear tattoos equally. The age group 20-29 years dominates with almost 50% having tattoos. The following article describes the new regulations especially the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulation, legal basis, and governmental controls on the subject of "tattoos". The composition of tattooing agents and testing options relevant for the user before and for the performance of tattooing are presented. Dermatologically associated diseases and testing procedures are listed. Since 70% of the population denies knowledge of this information even when they have tattoos themselves, this update is written as an overview for treating physicians and users.

Investigation of Adverse Reactions in Tattooed Skin through Histological and Chemical Analysis

BACKGROUND

Just as the number of tattooed people has increased in recent years, so has the number of adverse reactions in tattooed skin. Tattoo colourants contain numerous, partly unidentified substances, which have the potential to provoke adverse skin reactions like allergies or granulomatous reactions. Identification of the triggering substances is often difficult or even impossible.

METHODS

Ten patients with typical adverse reactions in tattooed skin were enrolled in the study. Skin punch biopsies were taken and the paraffin-embedded specimens were analysed by standard haematoxylin and eosin and anti-CD3 stainings. Tattoo colourants provided by patients and punch biopsies of patients were analysed with different chromatography and mass spectrometry methods and X-ray fluorescence. Blood samples of 2 patients were screened for angiotensin-converting enzyme (ACE) and soluble interleukin-2 receptor (sIL-2R).

RESULTS

Histology showed variable skin reactions such as eosinophilic infiltrate, granulomatous reactions, or pseudolymphoma. CD3+ T lymphocytes dominated the dermal cellular infiltrate. Most patients had adverse skin reactions in red tattoos (n = 7), followed by white tattoos (n = 2). The red tattooed skin areas predominantly contained Pigment Red (P.R.) 170, but also P.R. 266, Pigment Orange (P.O.) 13, P.O. 16, and Pigment Blue (P.B.) 15. The white colourant of 1 patient contained rutile titanium dioxide but also other metals like nickel and chromium and methyl dehydroabietate - known as the main ingredient of colophonium. None of the 2 patients showed increased levels of ACE and sIL-2R related to sarcoidosis. Seven of the study participants showed partial or complete remission after treatment with topical steroids, intralesional steroids, or topical tacrolimus.

CONCLUSIONS

The combination of the methods presented might be a rational approach to identify the substances that trigger adverse reactions in tattoos. Such an approach might help make tattoo colourants safer in the future if such trigger substances could be omitted.

“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.

Viral Infections Confined to Tattoos—A Narrative Review

Since ancient times, people have tattooed their skin for various reasons. In the past, tattoos were associated with low social status; nowadays, tattoos are very popular and are considered a form of art. However, tattoos are associated with various clinical problems, including immune reactions, inflammatory disorders, infections, and even skin cancer. Epidemiological and clinical data of infections on tattoos are scarce. Tattoo-related infections are mostly bacterial; only a few localized viral infections have been reported so far and are caused by molluscum contagiosum virus (MCV), human papillomavirus (HPV), and herpes simplex virus (HSV). In most cases, the lesions were strictly confined to the area of the tattoo. In this review, we have analysed reported cases of viral infections localized on tattoos and discussed the possible mechanisms involved in the occurrence of these infections.

What about Your Body Ornament? Experiences of Tattoo and Piercing among Italian Youths

BACKGROUND

tattooing and piercing are increasingly common, especially among youths. However, several health complications may be associated with these practices if basic hygiene rules are not respected. This multicenter study was aimed at exploring tattoo and piercing experiences reported by a large sample of Italian undergraduate students through a public health perspective.

METHODS

tattooed and/or pierced students attending 12 Italian universities were asked to complete a web-based questionnaire regarding their body art experience.

RESULTS

out of 1472 respondents, 833 (56.6%) were tattooed and 1009 (68.5%) were pierced. The greatest proportion of tattooed students (93.9%) got her/his first tattoo in a tattoo studio, while most of the pierced were serviced in a jewelry store (48.0%). The pierced ones were less informed on health issues related to the procedure (56.0% versus 77.8% of tattooed p < 0.001), and tattooists were reportedly more attentive to hygiene rules (instrument sterilization 91.5% versus 79.1% of piercers, p < 0.001; use of disposable gloves 98.2% versus 71% of piercers, p < 0.001).

CONCLUSIONS

educational interventions for both professionals and communities are needed to improve the awareness and the control of health risks related to body art throughout the Italian territory.

Immunological Mechanisms of Metal Allergies and the Nickel-Specific TCR-pMHC Interface

Besides having physiological functions and general toxic effects, many metal ions can cause allergic reactions in humans. We here review the immune events involved in the mediation of metal allergies. We focus on nickel (Ni), cobalt (Co) and palladium (Pd), because these allergens are among the most prevalent sensitizers (Ni, Co) and immediate neighbors in the periodic table of the chemical elements. Co-sensitization between Ni and the other two metals is frequent while the knowledge on a possible immunological cross-reactivity using in vivo and in vitro approaches remains limited. At the center of an allergic reaction lies the capability of a metal allergen to form T cell epitopes that are recognized by specific T cell receptors (TCR). Technological advances such as activation-induced marker assays and TCR high-throughput sequencing recently provided new insights into the interaction of Ni2+ with the αβ TCR-peptide-major histocompatibility complex (pMHC) interface. Ni2+ functionally binds to the TCR gene segment TRAV9-2 or a histidine in the complementarity determining region 3 (CDR3), the main antigen binding region. Thus, we overview known, newly identified and hypothesized mechanisms of metal-specific T cell activation and discuss current knowledge on cross-reactivity.