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.

Tattoo-Associated Skin Reactions: A Danish Population-Based Survey in 5,914 Tattooed Individuals.

BACKGROUND: In Europe, Australia, and the USA, the estimated overall prevalence of tattooing is around 10-20%. Tattoo ink often comprises harmful chemicals and epidemiological studies on adverse effects of tattoos are lacking. OBJECTIVES: We aimed to estimate the prevalence of tattoo-associated skin reactions in the general Danish population and describe individuals with tattoo-associated skin reactions by socio-demographic factors and tattoo characteristics. METHODS: The study was based on respondents aged 16 years or older from a population-based 2021 survey entitled "How are you?" conducted in the Central Denmark Region (n = 33,925). Logistic regression was used to characterise individuals with tattoo-associated skin reactions by socio-demographic factors (gender, age, educational level, and ethnic background). Also, the relationship between size, age and colour of the tattoo, and tattoo-associated skin reactions was studied. Model 1 was adjusted for all socio-demographic variables (gender, age, educational level, and ethnic background); model 2, for all socio-demographic variables and tattoo characteristics (size, age, and colour). RESULTS: In total, 21.1% reported that they had at least one tattoo, 10.2% hereof reported that they had experienced tattoo-associated skin reactions (itching, pain, inflammation, and swelling) beyond the first 3 weeks after the tattoo was made. Lower age (16-44 years) (adjusted odds ratio (AOR) ≥1.75), larger tattoos (AOR ≥1.61) and having had tattoos for more than 10 years (AOR = 2.92, 95% confidence interval 1.45-5.88) increased the odds of tattoo-associated skin reactions. In general, tattooed individuals with colours other than black had higher odds of tattoo-associated skin reactions. CONCLUSION: Among participants with at least one tattoo, 10.2% had experienced tattoo-associated skin reactions beyond the first 3 weeks after their tattoo was made. This finding highlights the need for safer tattoo inks to prevent the adverse health problems experienced by many individuals with tattoos.

"Tattoo Characteristics and Testing for Body Dysmorphic Disorder: An Internet-based Self-questionnaire Survey of 4,809 Individuals with Tattoos".

Tattoos have become very popular worldwide in recent years. The aim of this study was to analyse a group of people interested in having tattoos, and screen them for body image disturbances. This cross-sectional self-administered internet-based survey included 4,809 individuals interesting in having tattoos. The majority of the study population were female (79.1%). The survey was conducted using a self-created questionnaire and the Body Dysmorphic Disorder Questionnaire - Dermatology version. Most tattoos in the study group were located on the forearms and hands (28.1%). The most popular motifs were plants (17.5%) and animals (16.9%). Out of 4,809 individuals, 19.9% had problems with acceptance of some parts of their body and 9.8% were screened for body dysmorphic disorder with the Body Dysmorphic Disorder Questionnaire - Dermatology version. Four percent of individuals reported that tattoos helped to improve their own perception of the appearance of their body by distracting attention from the other problems. Limitations of this study include possible participant selection bias and the overrepresentation of women. In conclusion, clinicians may expect to see more patients with tattoos and, of these, approximately 10% may be screened for body dysmorphic disorder.

Tattoo-induced allergic contact dermatitis presents diagnostic challenge as a cellulitis mimic.

Allergic contact dermatitis (ACD) is a prevalent condition associated with numerous potential allergen exposures. Tattoo ink is variable and may contain allergens that can be overlooked in patient education and diagnosis. We present a 27-year-old female with ACD following a new tattoo. The patient was repeatedly misdiagnosed with cellulitis by three different clinicians and treated with multiple antibiotics without improvement. The correct diagnosis was eventually made in the emergency department (ED). Although the patient was aware of her allergies to nickel and cobalt from patch testing, she was not aware of the potential for tattoo ink to contain these allergens because prior tattoos had not provoked an allergic reaction. Consequently, the appropriate care was delayed by a month, resulting in significant morbidity. This case demonstrates the potential for ACD to present similarly to cellulitis in an ED setting and the need for clinical vigilance in diagnosis of ACD. It also highlights the importance of detailed patient education on potential allergen sources particularly in the context of tattooing, which is performed with unregulated and variable ink products.

Features of tattoo-associated cutaneous lymphoid hyperplasia on reflectance confocal microscopy and line-field confocal optical coherence tomography.

The popularity of tattoos has led to an increase in associated skin reactions, including complications such as infection, allergic reactions and rare conditions such as tattoo-induced cutaneous lymphoid hyperplasia (CLH). CLH is a benign lymphoproliferative reaction with clinical features resembling malignant cutaneous lymphomas. Non-invasive diagnostic tools like reflectance confocal microscopy (RCM) and the new line-field confocal optical coherence tomography (LC-OCT) are being studied in dermatology better to understand the morphological patterns of many dermatological diseases. Between September 2021 and May 2023, patients with suspicious lesions for tattoo-related CLH were analysed using RCM and LC-OCT before confirming the diagnosis of CLH through skin biopsy and histopathological examination. The study included five cases of CLH. It focused on the analysis of high-quality LC-OCT images/videos and RCM images to investigate the features of CLH in tattooed individuals. Most (80%) cases exhibited a mixed T and B lymphocyte infiltration subtype, while 20% showed a predominant T infiltration subtype. RCM and LC-OCT revealed characteristic features, including architectural disarray, fibrosis, lymphoid infiltrates, and pigment deposits in the epidermis and dermis. Non-invasive tools such as RCM and LC-OCT are valuable in diagnosing tattoo-related CLH. While skin biopsy remains the current standard for diagnosis, RCM and LC-OCT can serve as helpful adjuncts in identifying the most representative area for biopsy. They may potentially become alternative diagnostic options in the future, offering benefits in terms of cost, diagnostic efficiency, aesthetics and patient satisfaction as the prevalence of tattoo-related adverse reactions continues to rise.

Does corneal tattooing affect the conjunctival microbiota?

PURPOSE: This study aimed to investigate the effects of commercial tattoo inks used in corneal tattooing on conjunctival microbiota. METHOD: This prospective case control study consisted of 125 participants divided in the following three groups: 35 patients with corneal tattoos, 40 patients with corneal leukoma, and 50 healthy subjects. Corneal tattooing was performed in all the cases in this study using a tattoo pen machine and commercial tattoo ink. A total of 500 cultures were taken from 250 eyes of 125 individuals on chocolate and sheep blood agar. Bacteriological samples were taken from the inferior eyelid conjunctiva using a sterile cotton swab. Without any contact elsewhere, the swabs were smeared on bedside chocolate agars and 5% sheep blood agar. RESULTS: In tattooed eyes, bacterial growth was detected in 42.9% of the chocolate and sheep blood agar samples. In other healthy eyes of patients with corneal tattoos, 54.5% bacterial growth on chocolate agar and 57.1% on sheep blood agar were detected. No statistical difference was detected in the conjunctival microbiota of chocolate and sheep blood agar (p = 0.254, p = 0.134, respectively) in the tattooed eyes compared to the other eye of the individual. No statistically significant difference was found in terms of bacterial growth in tattooed, leukoma, or healthy eyes on chocolate and sheep blood agar (p = 0.408, p = 0.349). The growth rate of Staphylococcus epidermidis decreased by 33.3% (from 12 to 8) on chocolate agar in 35 tattooed eyes, and it decreased by 28.5% (from 14 to 10) on sheep blood agar, while gram-negative bacteria Brevundimonas diminuta, Acinetobacter lwoffii, and Psychrobacter faecalis were detected in three patients. CONCLUSION: Corneal tattooing using commercial dye does not affect conjunctival microbiota. In the past 3 years, 120 patients have been tattooed with commercial tattoo ink in Istanbul Medeniyet University Göztepe Training and Research Hospital. No complications related to infection were found in the 3-year follow-up. The gram-negative bacteria detected in the healthy control group and tattooed eyes were bacteria found on normal skin or in the respiratory tract. Although some gram-negative bacteria do not cause infection, careful eye examination, follow-up, and culture are required in suspicious cases.

Are Some Metals in Tattoo Inks Harmful to Health? An Analytical Approach.

Tattoo application is widely performed all over the world; however, injection of coloring substances into the skin as metals may pose a risk for allergies and other skin inflammations and systemic diseases. In this context, tattoo inks in green, black, and red colors of three brands were purchased. Before starting the analysis, the acid mixture suitable for microwave burning was determined, and according to these results, the inks were digested with nitric acid, hydrochloric acid, and hydrofluoric acid. Then, method validation was performed for tattoo inks using inductively coupled plasma-mass spectrometry. The relative contribution of metals to the tattoo ink composition was highly variable between colors and brands. Elements found in the main components of inks are as follows (in mg kg-1): Al, 1191.1-3424.9; Co, 0.04-1.07; Cu, 1.24-2523.4; Fe, 16.98-318.42; Ni, 0.63-17.53; and Zn, 2.6-46.9. It has been determined by the Environmental Protection Agency that in some products, especially the copper element is above the determined limit. The analysis results obtained were classified by chemometric analysis, and the color and brand relationship were determined. More toxicological studies are necessary to understand the effects of tattoo inks containing heavy metals and/or organic components.

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.

Aesthetic corneal tattooing/keratopigmentation using tattoo pen machine: choosing suitable method and color.

PURPOSE: This article aims to present the corneal tattooing method and how using a tattoo pen machine can improve aesthetic appearance in patients with corneal leukoma. METHODS: In this study, 42 patients were evaluated who had no visual potential and who had undergone colored corneal tattooing using an automatic tattoo pen machine for aesthetic purposes. The procedure was conducted according to the principles of the Declaration of Helsinki. The commercially available tattoo ink that has traditionally been used on human skin (brown, green, and black) for years was used for all the patients in this study, and 252 corneal photographs (with a Topcon slit lamp imaging device at 16 magnifications, i.e., 16 ×) taken within the last 2 years were evaluated retrospectively. Red, green, and blue (RGB) and hue, saturation, and lightness (HSL) values of the tattooed areas, such as pupils and iris, in corneal photographs were determined online using the Color Code Finder program. The RGB and HSL values of the pupil and iris were compared before surgery on the first day and first week, first month, third month, and twelfth month after surgery. RESULTS: In the first postoperative month, the mean pupil lightness (L) and iris L values were found to have increased by 10.7% and 5.7%, respectively. Between the first month and the first year, the L value of the mean pupil and that of the iris increased by 1.7% and 5.2%, respectively. The increase in the RGB value of the mean pupil in the first month was statistically significant (p = 0.02). The highest increase in RGB values of the iris was observed in the first week and first month (p = 0.113). This result shows that the majority of fading occurred in the first month. After the first month, the increase in the L value in the black-colored pupil was less than that in the brown- or green-colored iris. These results show that light colors fade faster and more. CONCLUSION: Esthetically, corneal leukoma causes severe psychological problems. Many patients are unable to use prosthetic contact lenses. Evisceration surgery has many complications, and limbal stem cells are used in evisceration surgery. Corneal tattooing using a tattoo pen machine is an easy, practical, and repeatable method used for aesthetic purposes. Successful results require the use of appropriate methods, ink, and ophthalmologist's experience. All patients in this study had a more aesthetic appearance than the preoperative white eye. Further studies are needed to develop a colored aesthetic tattooing method with a tattoo pen machine.

Granulomatous tattoo reaction treated with topical allopurinol.

Granulomatous reactions to tattoo ink have been frequently associated with exogenous pigment, although sometimes they are the manifestation of a cutaneous or an underlying systemic sarcoidosis. We report a case of a patient with a granulomatous reaction to a black tattoo pigment treated with 3% topical allopurinol for 3 months. We observed complete resolution without any side-effects. Examination and follow-up ruled out sarcoidosis. Oral allopurinol has been proven to be effective for the management of granulomatous reactions to tattoos. Based on the significant improvement we have described in our patient, we recommend new studies to reveal all the potential benefits of the topical use of allopurinol for the treatment of granulomatous reactions to tattoo ink.

On the mechanism of painful burn sensation in tattoos on magnetic resonance imaging (MRI). Magnetic substances in tattoo inks used for permanent makeup (PMU) identified: Magnetite, goethite, and hematite.

BACKGROUND: Persons with cosmetic tattoos occasionally experience severe pain and burning sensation on magnetic resonance imaging (MRI). OBJECTIVE: To explore the culprit magnetic substances in commonly used permanent makeup inks. MATERIAL AND METHODS: 20 inks used for cosmetic tattooing of eyebrows, eyeliners, and lips were selected. Ink bottles were tested for magnetic behavior with a neodymium magnet. Eight iron oxide inks qualified for the final study. Metals were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The magnetic fraction of inks was isolated and analyzed by X-ray fluorescence (XRF). Magnetic iron compounds were characterized by Mössbauer spectroscopy and powder X-ray diffraction (XRD). RESULTS: ICP-MS showed iron in all magnetic samples, and some nickel and chromium. Mössbauer spectroscopy and XRD detected ferromagnetic minerals, particularly magnetite, followed by goethite and hematite. CONCLUSION: This original study of cosmetic ink stock products made with iron oxide pigments reports magnetic impurities in inks for cosmetic tattooing, e.g., magnetite, goethite, and hematite. These may be the main cause of MRI burn sensation in cosmetic tattoos. The mechanism behind sensations is hypothesized to be induction of electrical stimuli of axons from periaxonal pigment/impurity activated by magnetic force. Magnetite is considered the lead culprit.

Efficacy and Safety of 5-Fluorouracil Tattooing to Repigment Idiopathic Guttate Hypomelanosis: A Split-Body Randomized Trial.

BACKGROUD: Idiopathic guttate hypomelanosis (IGH) is a common skin disorder with no standard treatment. OBJECTIVE: Assess the efficacy and safety of 5-fluorouracil (5FU) compared with saline, delivered using a tattoo machine, to repigment IGH lesions. METHODS: This split-body randomized single-blinded trial recruited adults with symmetrical IGH lesions. A tattoo machine was used to deliver 5FU in IGH lesions of 1 limb and saline in the contralateral limb. Outcomes were the number of achromic lesions 30 days after treatment compared with baseline, patient satisfaction, and local or systemic adverse events. RESULTS: Twenty-nine patients (28 women) were included. The median number of achromic lesions decreased significantly in 5FU-treated limbs (baseline: 32, interquartile range (IQR) 23-37 × post-treatment: 12, IQR 6-18, p = .000003) and saline-treated limbs (baseline: 31, IQR 24-43 × post-treatment: 21, IQR 16-31, p = .000006), but reduction was significantly more pronounced in 5FU-treated limbs ( p = .00003). All participants were satisfied or very satisfied with results on 5FU-treated limbs. There were no adverse events. CONCLUSION: 5-fluorouracil delivery using a tattoo machine was more effective than saline to repigment IGH lesions, with high patient satisfaction and no adverse events.Clinicaltrials.gov : NCT02904564.

Don't Go Breaking My Heart: Not Your Ordinary Tattoo Reaction.

ABSTRACT: Necrobiosis lipoidica (NL) is a rare, chronic idiopathic granulomatous dermatitis with a somewhat controversial association with diabetes and other systemic diseases. We report a case of NL developing within a polychromic tattoo on the lower leg of a 53-year-old woman. Characteristic histopathologic findings of both active and chronic "burnt-out" NL appeared to originate from the tattoo where red ink was used 13 years prior. To the best of our knowledge, only 3 other cases of tattoo-associated NL have been reported.

Microblading-Induced Granulomatous Reaction: Case Report and Review of the Literature.

ABSTRACT: Microblading is a common cosmetic procedure that can modify the appearance of one's eyebrows. Although generally well-tolerated, the procedure can cause a number of dermatologic issues; on rare occasions, granulomatous reactions can manifest. We use this case to highlight a presentation of a nonsarcoidal granulomatous dermatitis and review the literature on granulomatous reactions secondary to microblading. Of the 21 cases included in our review, approximately half (10/21) were diagnosed with foreign-body granulomas and the other half with sarcoidosis (7 of 21 with systemic sarcoidosis and 4 of 21 with cutaneous sarcoidosis). Although microblading remains a commonplace cosmetic technique, it is not without risk. Much like other types of tattoos, microblading can cause granulomatous reactions for which we must be vigilant, and further workup for sarcoidosis might be considered in select patients.

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.

Lasers for the treatment of eyebrow microblading and cosmetic tattoo pigment: a review of the literature.

We aim to discuss the use of laser for the treatment of eyebrow microblading and cosmetic tattoo complications through a review of the literature. Our research question is whether quality-switched or picosecond laser is superior for the removal of eyebrow tattoos. This structured review was conducted using a PubMed search using the search terms "laser tattoo removal" AND "cosmetic tattoo" AND "eyebrow" with the article type filtered to "case reports," "clinical trial," and "randomized controlled trial" ranging from dates 1994-2023. All case reports or series evaluating the effect of laser on eyebrow cosmetic tattooing pigment were included. We summarize the results of 11 studies evaluating the use of laser for cosmetic tattoo removal, with 129 patients treated specifically for eyebrow pigment. Most studies (8/11) report Fitzpatrick skin type or race. Seven studies utilize quality-switched (QS) neodymium-doped yttrium aluminum garnet (Nd:YAG), alexandrite or ruby, three used picosecond (PS) Nd:YAG or alexandrite, and three used carbon dioxide (CO2) laser. We report laser energy, spot size, and pulse duration, as well as treatment outcomes and adverse events. Historically, methods of pigment removal included dermabrasion, cryosurgery, electrosurgery, radiofrequency, infrared light, intense pulsed light, and surgical excision; however, these methods often led to poor cosmetic outcomes including scarring and further dyspigmentation. QS laser treatments provided superior cosmetic outcomes and thus were considered the gold standard treatment option for pigment removal. However, the advent of PS lasers has challenged this given their increased selectivity, lower fluence requirements, and reduction in surrounding thermal damage. Our review demonstrates that PS Nd:YAG is quicker and more effective that QS Nd:YAG in the treatment of eyebrow tattoos. Additionally, the paradoxical darkening seen with QS lasers is less common with PS lasers. We also demonstrate that CO2 laser may be a helpful adjunct to QS or PS laser. This review focuses on Fitzpatrick skin type and race, providing a unique perspective on the use of laser treatment in skin of color, which often poses an additional treatment challenge.

Monkeypox virus transmission in tattoo parlor.

In monkeypox virus (MPXV) transmission caused by contaminated material, we have to consider that recently the outbreak of several MPXV cases was linked to tattoo parlors in Cadiz, Spain. These tattoo parlors did not cause a single outbreak, but instead are an established transmission route for MPXV, underscoring the need for increased awareness. We recommend increasing awareness among tattooists and piercers not only to protect their own safety and health, but also to prevent spreading the virus to their customers. Personal protective equipment such as gloves should be utilized and vaccination can be considered for those at risk of occupational exposure.

Tattoo Pigment Identification in Inks and Skin Biopsies of Adverse Reactions by Complementary Elemental and Molecular Bioimaging with Mass Spectral Library Matching.

Tattooing has become increasingly popular throughout society. Despite the recognized issue of adverse reactions in tattoos, regulations remain challenging with limited data available and a missing positive list. The diverse chemical properties of mostly insoluble inorganic and organic pigments pose an outstanding analytical challenge, which typically requires extensive sample preparation. Here, we present a multimodal bioimaging approach combining micro X-ray fluorescence (µXRF) and laser desorption ionization-mass spectrometry (LDI-MS) to detect the elemental and molecular composition in the same sample. The pigment structures directly absorb the laser energy, eliminating the need for matrix application. A computational data processing workflow clusters spatially resolved LDI-MS scans to merge redundant information into consensus spectra, which are then matched against new open mass spectral libraries of tattoo pigments. When applied to 13 tattoo inks and 68 skin samples from skin biopsies in adverse tattoo reactions, characteristic signal patterns of isotopes, ion adducts, and in-source fragments in LDI-MS1 scans yielded confident compound annotations across various pigment classes. Combined with µXRF, pigment annotations were achieved for all skin samples with 14 unique structures and 2 inorganic pigments, emphasizing the applicability to larger studies. The tattoo-specific spectral libraries and further information are available on the tattoo-analysis.github.io website.

Chemical characterization of inks in skin reactions to tattoo.

Skin reactions are well described complications of tattooing, usually provoked by red inks. Chemical characterizations of these inks are usually based on limited subjects and techniques. This study aimed to determine the organic and inorganic composition of inks using X-ray fluorescence spectroscopy (XRF), X-ray absorption spectroscopy (XANES) and Raman spectroscopy, in a cohort of patients with cutaneous hypersensitivity reactions to tattoo. A retrospective multicenter study was performed, including 15 patients diagnosed with skin reactions to tattoos. Almost half of these patients developed skin reactions on black inks. XRF identified known allergenic metals - titanium, chromium, manganese, nickel and copper - in almost all cases. XANES spectroscopy distinguished zinc and iron present in ink from these elements in endogenous biomolecules. Raman spectroscopy showed the presence of both reported (azo pigments, quinacridone) and unreported (carbon black, phtalocyanine) putative organic sensitizer compounds, and also defined the phase in which Ti was engaged. To the best of the authors' knowledge, this paper reports the largest cohort of skin hypersensitivity reactions analyzed by multiple complementary techniques. With almost half the patients presenting skin reaction on black tattoo, the study suggests that black modern inks should also be considered to provoke skin reactions, probably because of the common association of carbon black with potential allergenic metals within these inks. Analysis of more skin reactions to tattoos is needed to identify the relevant chemical compounds and help render tattoo ink composition safer.

Inking outside the box: systematic review on the utility of tattooing lesions in rectal cancer.

PURPOSE: Endoscopic tattooing in rectal cancer is infrequently utilized for fear of tattoo ink obscuring anatomical planes, increasing the difficulty of surgical excision. Colon cancer tattooing has demonstrated increased lymph node yields and increased accuracy in establishing adequate margins. Rectal cancer tattooing may be especially helpful after neoadjuvant chemoradiation, where complete clinical responses could limit lesion identification and lymph node yields are typically less robust. We seek to review and identify the effects of tattooing in rectal cancer. METHODS: A systematic literature search was performed in PubMed, Embase, and SCOPUS. Studies on endoscopic tattooing with cohorts consisting of at least ≥ 25% of rectal cancer patients were selected. Studies focusing solely on rectal cancer were also reviewed separately. RESULTS: Of 416 studies identified, 10 studies encompassing 2460 patients were evaluated. Seven studies evaluated lymph node yields; five reported beneficial effects of endoscopic tattooing, while two reported no significant difference. Among four studies reporting lesion localization, successful localization rates were between 63 and 100%. Rates of intraoperative endoscopy performed to reevaluate lesion location ranged from 5.7 to 20%. The distal margin was evaluated in two studies, which reported more accurate placement of the distal resection margin after tattooing. When complications of tattooing were documented (7 studies with 889 patients), only five direct complications of endoscopic tattooing were observed (0.6%). CONCLUSIONS: Although the data is heterogenous, it suggests that endoscopic tattooing in rectal cancer may improve lymph node yields and assist in determining accurate distal margins without high rates of complication. Further research must be completed before practice management guidelines can change. TRIAL REGISTRATION: No. CRD42021271784.