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... The corresponding spectra are reported in Figure 1A,B. The choice of the reference pigments was made on the basis of the declared content on the bottle of EGC and what was actually found in the GC ink bottles [19,38]. ...
... Both SedAGC and SedEGC display a one-to-one correspondence to the PG7 Raman features, within 4 cm −1 , a difference which can be related to instrumental error as well as to the contribution of residual additives [19]. Therefore, also Raman spectra indicate that both Asian and European inks contain PG7. ...
... The detailed assignments of the IR features can be retrieved from [19], whereas the assignment of the Raman features of PG7, PG36, SedAGC and SedEGC are reported in Table S1 of the Supplementary Information. ...
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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.
... In addition, the inks often contain by-products or precursors from the production of the pigments, many of which were originally designed for other industries [8]. The pigments can consist of inorganic molecules, such as titanium dioxide, in the case of white inks and many coloured inks as a tinting agent, organometallic complexes, such as phthalocyanines in the case of blue and green inks, or organic molecules, such as azo compounds in the case of yellow-, red-and orange-coloured inks [1,9], examples of which are given in Fig. 1. As these pigments tend to have a low solubility in the carrier, which is often either water, glycerol, alcohols, witch hazel or some combination thereof, dispersants are often required to avoid aggregation [9]. ...
... The pigments can consist of inorganic molecules, such as titanium dioxide, in the case of white inks and many coloured inks as a tinting agent, organometallic complexes, such as phthalocyanines in the case of blue and green inks, or organic molecules, such as azo compounds in the case of yellow-, red-and orange-coloured inks [1,9], examples of which are given in Fig. 1. As these pigments tend to have a low solubility in the carrier, which is often either water, glycerol, alcohols, witch hazel or some combination thereof, dispersants are often required to avoid aggregation [9]. In addition, the concentration of tattoo pigment that is deposited in the skin can vary significantly, with reported ranges between 0.60 and 9.42 mg/cm 2 [10]. ...
... However, increasingly, concerns have been raised about the safety and long-term health effects of tattoo inks and their components as indicated by the drafting of tattoo ink guidelines [11,12]. Initially, health concerns regarding ink composition focused on metals such as arsenic, lead and mercury that were originally used as pigments [1,9]. In a study undertaken by the New Zealand Ministry of Health, nine metals were found to be greater than the United States Environmental Protection Agency's recommended concentrations in as many as 24% of the samples tested, though, with the exception of barium and copper, most metals tested were likely impurities. ...
Article
The popularity of tattooing has increased significantly over recent years. This has raised concerns about the safety of tattoo inks and their metabolites/degradation products. The photolytic and metabolic degradation of tattoo pigments may result in the formation of toxic compounds, with unforeseen health risks. A systematic literature review was undertaken to determine the current state of knowledge of tattoo pigments’ degradation products when irradiated with sunlight, laser light or metabolised. The review demonstrates that there is a lack of knowledge regarding tattoo pigment degradation/metabolism, with only eleven articles found pertaining to the photolysis of tattoo pigments and two articles on the metabolism of tattoo pigments. The limited research indicates that the photolysis of tattoo pigments could result in many toxic degradation products, including hydrogen cyanide and carcinogenic aromatic amines.
... Addressing tattoos with lasers usually carries an unknown, because the composition of the earliest inks on the market did not need to be declared, and in many countries, it is still the case. In countries where regulations were enforced on tattoo inks labeling (Code of Federal Regulations 2015;ResAP 2008;TätoV 2008;Swiss Regulation 2005), systematic violations and false declarations (Bauer et al. 2019;Hauri 2014) jeopardize suited laser treatments. ...
... In Bocca et al. (2017), analyzed 9 inks of different colors and found a large size polydispersion, with particles continuously distributed from tens to hundreds of nanometers. TiO 2 nanoparticles in the 20-30 nm range were found in a green ink, with the white pigment as a lightening agent (Bauer et al. 2019). As for the fate of the inks nanoparticles and aggregates upon laser treatments, to date, we found only one paper reporting ink re-aggregation and ejection at high speed (Murphy 2018), which is of potential harm to personnel removing the tattoos and may have consequences for the treated person. ...
... The ensuing spectra are reported in Fig. 1a), whereas, the list of the peaks are reported in Table SI1 of the Supplementary Information. The features of PG36 and PG7 were previously analyzed (Bauer et al. 2019) and the assignments are briefly summarized here. The most significant bands and largest differences between the two pigments are in the region 1800-400 cm −1 . ...
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Since tattoos became overwhelmingly fashionable worldwide, the demand for removal has proportionally increased, Nd:YAG Q-switch laser being the most commonly used tool for the purpose. In this framework we investigated the composition and products of laser treatment of green tattoo ink, the Green Concentrate from Eternal. The ink characterization has been carried out by IR, UV–Vis, EDX spectroscopies, and SEM imaging. It revealed the presence of the pigment PG7, rather than PG36 as reported on the bottle label, along with non-fully halogenated analogues. The morphology is an extended sheath with embedded grains. Subsequent laser treatments were performed on both dried and extracted inks, dispersed either in water or in propan-2-ol, chosen for their different polarities, as it is the case in the skin layers. The products were analyzed by gas chromatography-mass spectrometry, UV–Vis spectroscopy, SEM imaging, and dynamic light scattering. The outcome is a complex fragmentation pattern that depends both on the solvent and on the initial aggregation state. The fragment compounds are toxic at various degrees according to the Classification Labelling and Packaging regulations. Several shapes of aggregates are produced as an effect of both downsizing and re-aggregation, with potentially harmful aspect ratios.
... Also, in parallel, numerous regulation violations were revealed. 32,33 Italy is one of the European countries in which such legislation has not yet been implemented. In 2016, a law was proposed on safety conditions for tattooing, but it has still to be passed. ...
... One issue can be the correspondence between the real and declared composition of inks and possible false declarations. 33 In this case, the issue can be developed regarding the methods to determine the ink composition. 51 In other cases, if the legislation becomes the main topic, it can be assessed whether to find the regulations, 27−32 and how to compare them to the labels. ...
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Within the framework of a nationwide project to boost students’ enrollment in scientific disciplines in Italy, a multilevel science project was designed with a focus on the chemistry of tattoo inks, offering immediate connection with 16–18 year-old high school students. The approach takes into account time constraints, since all sessions have a maximum span of 8 h, and the heterogeneity of the audience, made up of students without background restrictions. Tattoos are perceived as a form of body art and can be conveniently used as the “A” in the STEAM (science, technology, engineering, art, and mathematics) methodology. The project involved active lectures and guided inquiry into the simple chemical concepts related to tattoo inks, addressed in practical units with multioutcome experiments and comparative instrumental analysis. The connections with correlated issues, such as norms regarding tattoo ink composition and verification, were also discussed. The efficacy of the tattoo ink Scientific Degree Plan experience was then evaluated through two types of surveys: one on the enjoyment of the plan and the other on mastery of the chemical concepts at the end of the experience.
... Obtained by inserting pigment micro-or nano-particles into the dermis using needles, tattoos can cause various cutaneous reactions, such as non-allergic inflammatory reactions and allergic reactions to certain pigments and metal particles contained in the tattoo ink. CRM was used to characterize ex vivo and in vivo tattoo inks of different colors [34][35][36] and identify tattoo inks causing skin reactions [37,38]. CRM is also capable of providing ink composition and one-dimensional (1D) depth distribution down to 400 µm [36], which could be of interest for laser removal. ...
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Line-field confocal optical coherence tomography (LC-OCT) is an optical modality that provides three-dimensional (3D) images of the skin at cellular resolution. Confocal Raman microspectroscopy (CRM) is a label-free optical technique that can provide point measurement of the molecular content of the skin. This work presents a method to co-localize LC-OCT and CRM acquisitions for morpho-molecular analysis of ex vivo skin tissues at cellular level. The co-localization method allows acquisition of Raman spectra at specific locations in a sample identified from a 3D LC-OCT image, with an accuracy of ± 20 µm. The method was applied to the characterization of tattooed skin biopsies with adverse tattoo reactions. LC-OCT images allowed to target specific regions in the biopsies where the presence of tattoo ink was revealed by detection of the Raman signature of ink pigments. Micrometer-sized foreign bodies of various materials as well as inflammatory cells were also identified within the biopsies. From these results, we demonstrate the value of the LC-OCT-CRM co-localization method and its potential for future ex vivo analysis of suspicious skin lesions.
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The tattoos removal has become an issue upon spread of the tattooing practice worldwide and hindsight regrets. Lasers are typically used for the purpose, though some colours such as green are considered “recalcitrant” to the treatment. In the current investigation, we aim at determining the efficacy of removal of a green ink water dispersion, using 5 laser treatments: Nd:YAG nano- and picosecond lasers in normal and array mode and Ruby nanosecond laser, keeping the total irradiated energy constant. The UV–Vis spectroscopy of the treated samples indicate that Nd:YAG picosecond laser is most effective, and the Ruby nanosecond laser is the least efficient. Fragment compounds generated from the pigment and siloxanes are common to all treatments, whereas hydrocarbon emerge by a larger amount upon Nd:YAG nanosecond treatment. Fibres are formed upon picosecond treatments and when operating in array mode, and lamellae are achieved by Ruby nanosecond laser treatment. Residual particles suspensions are very heterogeneous upon nanosecond treatments.
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The painted sculptures in ancient Chinese folk temples are important traditional folk painting art forms, and it is of great significance for painted sculptures conservation to study the materials and techniques employed in their production. In this study, firstly, the samples from eight different colored painted sculptures were collected at Fushan Temple (1595–1882 AD) in Heyang County, Shaanxi Province, China. Secondly, the surface morphology and cross-sectional structure of the painted sculptures were investigated using optical microscopy and scanning electron microscopy (SEM). In addition, qualitative and semi-quantitative studies of the elemental and physical phase compositions of the materials used in the manufacture of the painted sculptures were conducted by X-ray diffraction (XRD), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). The results showed that the painted sculpture samples from Fushan Temple comprised a pigment layer, white powder layer, fine clay layer, and coarse clay layer from the outside to the inside. The white powder layer was made of chalk, with functions in color development and leveling. The fine clay layer comprised quartz and other sand particles with small grain sizes. The coarse clay layer comprised feldspar and cotton silk, with larger grain size. In addition, the pigments used in the painted sculptures were chrome red, lapis lazuli, phthalocyanine green, earth green, amorphous carbon black, iron oxide red, and pyrite. The green pigment was earth green in the early stages but it was later repainted with phthalocyanine green mixed with some lapis lazuli pigments for toning. In addition, the dark green and brown pigments comprised mixtures of amorphous carbon black and phthalocyanine green, and amorphous carbon black and iron oxide red, respectively.
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Comparative laser and thermal treatments were carried out on PG36, a green phthalocyanine-based pigment, permitted in European countries where legislation on tattoo composition was issued. Prior to the treatments, PG36 was characterized by SEM imaging, EDX, IR and UV–Vis spectroscopies, revealing an excess of Si and C and O as compared to the pure halogenated Cu-phthalocyanine. Laser treatments were carried out with a Nd:YAG device applied to H2O and propan-2-ol dispersions. Pyrolysis and calcinations were carried out in air or under N2 flow. The outcome of the different procedures was analyzed by UV–Vis spectroscopy, GC–mass spectrometry, X-ray diffraction of the solid residues, SEM microscopy and dynamic light scattering. The comparative analysis indicated the production of different fragment compounds depending on the treatment, (pyrolysis or laser), and, to some extent, to the solvent of the dispersion, with pyrolysis generating a larger number of hazardous compounds. Hydrocarbons and cyclic siloxanes present as additives in PG36 were stable or degraded depending on the treatment. The morphology of the products is also treatment-dependent with nanoparticles < 20 nm and fibers being produced upon laser treatments only. Based on the experimental findings, the equivalence of laser and thermal treatments is evaluated.
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This study presents the synthesis of a series of new tetra-substituted phthalocyanines bearing 3,5-bis(trifluoromethyl)phenoxy groups on non-peripheral positions. The resulting macromolecules were characterized by performing different spectroscopic methods including 1H NMR, UV-Vis, FT-IR, and mass spectroscopy. In this study, the synergistic effect of phthalocyanines used as colorants in ink formulas with other chemicals available has been probed for the first time. The synergistic effects of compounds (2-5) on biological activity with methyl laurate were examined and antioxidant activities of the compounds were explored. Moreover, the therapeutic properties of the complexes (3, 6, and 7) were investigated using photochemical methods. As compared, complex 7 (∆=0.42) was found more effective than complex 6 (∆=0.40) and complex 3 (∆=0.27) in terms of producing singlet oxygen. The results confirmed that the heavy atom effect improves the therapeutic effects.
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This paper presents the results of the research on the influence of catalytic activity of iron(II) octacarboxyphthalocyanines (FePcOC) on the transformation of diclofenac (DCF) which is the most popular anti-inflammatory analgesic. Diclofenac poses a serious threat to the natural environment. The paper demonstrates that diclofenac, in the presence a monomeric form of iron octacarboxyphthalocyanine and hydroxyl radicals (HO•) (from H2O2), undergoes a transformation into diclofenac-2,5-iminoquinone (DCF-2,5-IQ), causing distinct changes in the UV–Vis absorption spectrum. In the presence of iron octacarboxyphthalocyanine and H2O2, the previously colourless diclofenac solution becomes intense orange. As a result, a new band at approx. 450 nm appears in the absorption spectrum. HPLC analysis has shown that the concentration of diclofenac decreases with time. TD-DFT calculations using the CAM-B3LYP/6-31+G (d, p) method have been conducted to confirm experimental data concerning the formation of a new band at λmax = 450 nm.
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The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body. We used skin and lymphatic tissues from human corpses to address local biokinetics by means of synchrotron X-ray fluorescence (XRF) techniques at both the micro (μ) and nano (ν) scale. Additional advanced mass spectrometry-based methodology enabled to demonstrate simultaneous transport of organic pigments, heavy metals and titanium dioxide from skin to regional lymph nodes. Among these compounds, organic pigments displayed the broadest size range with smallest species preferentially reaching the lymph nodes. Using synchrotron μ-FTIR analysis we were also able to detect ultrastructural changes of the tissue adjacent to tattoo particles through altered amide I α-helix to β-sheet protein ratios and elevated lipid contents. Altogether we report strong evidence for both migration and long-term deposition of toxic elements and tattoo pigments as well as for conformational alterations of biomolecules that likely contribute to cutaneous inflammation and other adversities upon tattooing.
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It is a subject of exploration whether the phase pure anatase or rutile TiO2 or the band alignment due to the heterojunctions in the two polymorphs of TiO2 plays the determining role in efficacy of a photocatalytic reaction. In this work, the phase pure anatase and rutile TiO2 have been explored for photocatalytic nitroarenes reduction to understand the role of surface structures and band alignment towards the reduction mechanism. The conduction band of synthesized anatase TiO2 has been found to be more populated with electrons of higher energy than that of synthesized rutile. This has given the anatase an edge towards photocatalytic reduction of nitroarenes over rutile TiO2. The other factors like adsorption of the reactants and the proton generation did not play any decisive role in catalytic efficacy.
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The widespread use of titanium dioxide nanoparticles (TiO2 NPs) is gradually increasing the risk of exposure to these potentially hazardous materials. Although numerous health effects of TiO2 NPs have been investigated, it remains unknown whether they could affect the respiratory cellular epigenome. We explored the viability, membrane integrity, intracellular ROS and genomic DNA methylation of human respiratory cells, as well as their expression of methylation-related genes, after treatment with TiO2 NPs with diameters of 25 nm (nanotube morphology) or 60 nm (anatase morphology). Two cell lines relevant to inhalation exposure, namely human bronchial epithelial cell line (16HBE) and human non-small cell lung cancer cells (A549), were tested, with treatment concentrations ranging from 0.1 to 100 μg mL⁻¹. The TiO2 NPs induced time- and concentration-dependent decreases in cell viability in both A549 and 16HBE cells. The reduction in cell viability was greater for the smaller particles (size 25 nm) of the nanotube type. Cellular membrane integrity assays revealed that 16HBE cells were less sensitive to TiO2 NPs-25 nm (nanotube-type) than were A549 cells, as higher concentrations were required for cytotoxicity against the former. TiO2 NPs-25 nm (nanotube-type) showed greater toxicity against both cell lines than TiO2 NPs-60 nm (anatase-type). Intracellular ROS levels in both A549 and 16HBE cell were increased by TiO2 NPs whereas pretreatment with the antioxidant N-acetyl-L-cysteine eliminated TiO2 NPs-induced ROS accumulation and reduced cell death. Moreover, the anatase-type TiO2 NPs resulted in decreased global DNA methylation and altered expression levels of methylation-related genes and proteins, suggesting that these NPs induce cellular epigenomic toxicity. These results allowed us to confirm the epigenetic mechanism by which TiO2 NPs damage human respiratory cells.
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We have applied different analytical techniques for studying the size and metal composition of nanoparticles (NPs) and microparticles in tattoo inks. The morphology and size distribution of particles were determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS). These techniques allowed us to obtain size information on all particles in tattoo mixtures. Higher resolution characterization of the size distributions was achieved by means of asymmetric flow field fractionation (AF4) combined with multi-angle light scattering (MALS) detection, which allowed for particle fraction separation and sizing. The high sensitivity and multi-elemental capability of inductively coupled plasma mass spectrometry (ICP-MS) enabled the off-line determination of the metal concentration of the particles in the AF4 fractions. Counting and sizing of particles were also performed by single particle (SP)-ICP-MS. The TEM images of the tattoo inks indicated the presence of individual particles and of aggregates and agglomerates of different shapes; carbon black was recognized in black inks and TiO2 in lighter shades. The DLS measurements showed that the inks were polydispersed with particles continuously distributed from tens to hundreds of nanometers (the Z-average hydrodynamic diameter range was 31-421 nm). The use of AF4 revealed the presence of two different fractions of particles in colored inks and one fraction in black inks, with mean sizes ranging from ca. 50 nm to ca. 400 nm. AF4 and off-line ICP-MS analyses of these fractions showed micronic and sub-micronic Al and Ti particles and Cu at the nanometer level (<100 nm). SP-ICP-MS analysis confirmed these latter findings: the inks contained nanosized materials of Cu (such as CuO or Cu-phthalocyanine), while Al (as Al2O3) and Ti (as TiO2) were detected as larger sized particles. Overall, this work confirms the power of different analytical techniques in detecting and characterizing NPs and microparticles in tattoo inks. We show that tattoo ink suspensions unquestionably contain NPs, suggesting the need for an assessment of how they interact with human skin as well as if they can penetrate the derma to reach the bloodstream.
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The implementation of regulation for tattoo ink ingredients across Europe has generated the need for analytical methods suitable to identify prohibited compounds. Common challenges of this subject are the poor solubility and the lack of volatility for most pigments and polymers applied in tattoo inks. Here, we present pyrolysis coupled to online gas chromatography and electron impact ionization mass spectrometry (py-GC/MS) as quick and reliable tool for pigment identification using both purified pigments and tattoo ink formulations. Some 36 organic pigments frequently used in tattoo inks were subjected to py-GC/MS with the aim to establish a pyrogram library. To cross-validate pigment identification, 28 commercially available tattoo inks as well as 18 self-made pigment mixtures were analyzed. Pyrograms of inks and mixtures were evaluated by two different means to work out the most reliable and fastest strategy for an otherwise rather time-consuming data review. Using this approach, the declaration of tattoo pigments currently used on the market could be verified. The pyrolysis library presented here is also assumed suitable to predict decomposition patterns of pigments when affected by other degradation scenarios, such as sunlight exposure or laser irradiation. Thus, the consumers’ risk associated with the exposure to toxicologically relevant substances that originate from pigment decomposition in the dermal layers of the skin can be assessed. Differentiation between more or less harmful pigments for this field of application now will become feasible. Electronic supplementary material The online version of this article (doi:10.1007/s00204-016-1739-2) contains supplementary material, which is available to authorized users.
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The determination methods of polycyclic aromatic hydrocarbons (PAHs), phthalates, primary amines, phenols, and metals in tattoo dyes have been optimized and validated using gas chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry, and inductively coupled plasma-mass spectrometry. Twelve PAHs, 3 phthalates, 4 amines, and 15 metals were identified and quantified in 16 different tattoo dyes purchased from shops in the Republic of Korea. Phenols were not detected in any sample. The total PAHs in six inks and benzo(a)pyrene in one tattoo ink exceeded the legal limit set by the Council of Europe, and their maximum detected concentrations were about 10 and 5 times the limits of the compounds, respectively. 3,3′-Dichlorobenzidine and o-anisidine, which should not be present in tattoo inks by Resolution ResAP (2008) of the Council of Europe, were detected in tattoo inks. Also, Cd, Pb, Cu, Ba, Ni, Sb, Zn, and As exceeded the limits. These hazardous compounds should be controlled to the lowest possible concentrations in the raw materials and the production procedure of tattoo ink.
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Tattoos have become increasingly popular in recent years. In the United States, the estimated percentage of adults with one or more tattoos increased from 14% in 2008 to 21% in 2012.(1) The process of tattooing exposes the recipient to risks of infections with various pathogens, some of which are serious and difficult to treat. Historically, the control of tattoo-associated dermatologic infections has focused on ensuring safe tattooing practices and preventing contamination of ink at the tattoo parlors - a regulatory task overseen by state and local authorities.(2) In recent months, however, reported outbreaks of nontuberculous mycobacterial infections associated with contaminated . . .
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Nowadays, practice of tattooing is very common worldwide and, along with this increasing trend, there is also an increased risk of adverse reactions to tattoo pigments that are well known and described in literature. Previous studies have reported that cutaneous and allergic reactions to a particular pigment can manifest in several ways (allergic contact dermatitis and photo-allergic dermatitis). In this paper, a new high-throughput method is presented, in order to achieve a new system for the quality control on tattoo inks based on chromatographic-spectroscopic approach. The samples, twenty-one tattoo inks and three permanent makeup, comprised the following colors: black inks, yellow, blue, green, white, pink and various shades of red (pigment that gives many allergic responses) were analyzed through the combination of chromatographic and spectroscopic techniques, the HPTLC-Raman. In particular, Raman technique has been chosen because of its high sensitivity towards the inorganic and organic pigments, main constituents of tattoo inks. Moreover, the advantage of this hyphenated technique is to overcome the problem of analysing the complex mixture of tattoo inks, allowing to obtain a Raman spectrum of each single component, isolated by chromatographic separation. This approach aims at developing a powerful instrument to establish the nature of tattoo inks and substances that could be cause adverse reactions in tattooed patients.
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As a result of the increase in the practice of tattooing, the US Food and Drug Administration has identified a need for improved analytical methods to detect the pigments and potential impurities in the inks. Raman spectroscopy allows for nondestructive identification of compounds and is commonly used in art, archaeology, and forensics; however, the technique has only limitedly been applied to the identification of tattoo pigments. In this study, approximately 30 inorganic, organometallic, and organic pigments were evaluated with Raman spectroscopy by using 532, 633, and 780-nm lasers. Individual optimization of the instrumental parameters was performed for each pigment in order to enhance spectral quality. This research highlights the need for multiple laser interrogation, as the spectra of some pigments were difficult to obtain by using a particular wavelength due to interferences from absorption or fluorescence. However, by using these multiple wavelengths, all pigments could be identified by their unique spectral features. A spectral library of the pigments was created for each laser wavelength and then challenged with pigments from multiple manufacturers. All pigments were identified correctly, and the method is poised to be an effective, noninvasive means for qualitatively identifying tattoo pigments. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
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Currently, the incidence of tattooing is on the rise compared to the past, especially among adolescents, and it leads to the urgency of monitoring the security status of tattooing centers, as well as to inform people about the risks of tattoo practice. In our clinical experience, 20% of tattooed patients presented adverse reactions, like allergic contact dermatitis, psoriasis with Koebner’s phenomena and granulomatous reactions, with the latter most prevalent and most often related to red pigment. Adverse reactions to tattoo pigments, especially the red one, are well known and described in literature. Great attention has to be focused on the pigments used, especially for the presence of new substances, often not well known. For this reason, we decided to perform a study on 12 samples of red tattoo ink, obtained by patients affected by different cutaneous reactions in the site of tattoo, to analyze their chemical composition. © 2016 Associazione Italiana Allergologi Immunologi Territoriali e Ospedalieri - AAITO.
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This comprehensive book covers various aspects of nanoscience and nanotechnology and what is known about the potential environmental and health impacts. Divided into three main sections, the book addresses the toxicity of nanomaterials, fate and transport of nanomaterials in the environment, and occupational health aspects of nanotechonology.
Article
Raman spectroscopy has proven to be a very useful tool for the forensic examination of various colored evidence, including its use in identifying pigments and dyes in paint and inks. Because both paint and inks consist of complex heterogeneous matrices, forensic scientists typically use a battery of different tests to characterize them, with each method contributing information that will be evaluated and integrated to produce an overall compositional profile. The contribution of the Raman method for the examination of these types of evidentiary materials will be described as well as the factors, which will show why this technique is suitable for the forensic endeavor. The literature offers abundant examples that show how Raman spectroscopy produces data that provide a very high degree of discrimination between samples, can perform non-destructive microscopical in situ analyses, requires minimal or no sample preparation, and produces data that can be easily stored for database purposes. In this review article, a comprehensive review of the forensic applications of Raman spectroscopy for the characterization, differentiation, comparison, and identification of trace evidence and questioned documents, consisting of paint and ink, respectively, is presented. Copyright © 2015 John Wiley & Sons, Ltd.
Article
Long perceived as a form of exotic self-expression in some social fringe groups, tattoos have left their maverick image behind and become mainstream, particularly for young people. Historically, tattoo-related health and safety regulations have focused on rules of hygiene and prevention of infections. Meanwhile, the increasing popularity of tattooing has led to the development of many new colours, allowing tattoos to be more spectacular than ever before. However, little is known about the toxicological risks of the ingredients used. For risk assessment, safe intradermal application of these pigments needs data for toxicity and biokinetics and increased knowledge about the removal of tattoos. Other concerns are the potential for phototoxicity, substance migration, and the possible metabolic conversion of tattoo ink ingredients into toxic substances. Similar considerations apply to cleavage products that are formed during laser-assisted tattoo removal. In this Review, we summarise the issues of concern, putting them into context, and provide perspectives for the assessment of the acute and chronic health effects associated with tattooing. Copyright © 2015 Elsevier Ltd. All rights reserved.
Article
Today's tattoo inks are no longer just simple solids in liquid suspension. Nowadays, these inks are high-tech dispersions made from finely spread pigments in a binder-solvent mixture. These so-called colour dispersions must follow the modern standards of tattooing, which are increasing every year. They must be rich in chromophoric pigments and yet fluid, they must not dry rapidly, and there should be no occurrence of any sedimentation, even during longer tattoo seasons. An innovative tattoo ink should enable long-lasting, brilliant tattoos without a negative impact on the artist's workflow and of course without endangering the consumer. The high standard in tattoos, regarding the motives and techniques, that is witnessed today could not be achieved by the artists without quality tools and modern tattoo ink. This article will give the reader a brief overview of the different ingredients of tattoo ink and of the function of binding agents and solvents in modern tattoo ink as well as describe what additives are used to achieve the desired behaviour during application. Furthermore, the article will take a look into the pigments that are used in tattoo ink and show why certain pigments are not suited for tattoo ink. The differences, advantages and disadvantages of organic and inorganic pigments will be explained. © 2015 S. Karger AG, Basel.
Article
Hair is one of the most common types of physical evidence found at a crime scene. Forensic examination may suggest a connection between a suspect and a crime scene or a victim, or demonstrate an absence of such associations. Therefore, forensic analysis of hair evidence is invaluable to criminal investigations. Current hair forensic examinations are primarily based on a subjective microscopic comparison of hair found at the crime scene with a sample of suspect's hair. Since this is often inconclusive, development of alternative and more accurate hair analysis techniques are critical. In this study, we utilized surface-enhanced Raman spectroscopy (SERS) to demonstrate that artificial dyes can be directly detected on hair. This spectroscopic technique is capable of a confirmatory identification of analytes with single molecule resolution, requires minimal sample, and has the advantage of fluorescence quenching. Our study reveals that SERS can (1) identify whether hair was artificially dyed or not, (2) determine if a permanent or semi-permanent colorants were used, and (3) distinguish the commercial brands that were utilized to dye hair. Such analysis is rapid, minimally destructive, and can be performed directly at the crime scene. This study provides a novel perspective of forensic investigations of hair evidence.
Article
Direct identification of pigments in mediaeval illuminated manuscripts was one of the first applications of Raman spectroscopy in art and archaeology. In previous in situ analysis of handwritings, the equipment was typically provided with a single excitation source. In this work, a portable Raman spectrometer (EZRAMAN-I-DUAL Raman system) is introduced to characterise the pigments used in an important illuminated mediaeval manuscript, De Civitate Dei (Library in Bruges, Ms.106). Characteristics important for these in situ measurements were discussed. We introduce a set-up that allows stable positioning of the equipment and point out the advantage of the availability of two lasers, which are part of the instrument. Good performance of the introduced Raman spectrometer, to allow pigment identification in a short time, is proved. Finally, pigments such as lead white (2PbCO3 · Pb(OH)2), lead–tin yellow type I (Pb2SnO4), malachite (Cu2CO3(OH)2), mosaic gold (SnS2), vermillion (HgS), carbon black (C), red lead (Pb3O4) and azurite (Cu3(CO3)2(OH)2) could be identified. These pigments were often used in mediaeval artworks and contribute to the enrichment of information of the materials used by the illuminator. Copyright © 2014 John Wiley & Sons, Ltd.
Article
Micro-Raman spectroscopy was applied to forensic identification of pigments in paint chips and provided differentiation between paint samples. Sixty-six blue automotive paint samples, 26 solid and 40 metallic were examined. It was found that the majority of the collected Raman spectra provided information about the pigments present. However, in some cases, fluorescence precluded pigment identification. Using laser excitation at longer wavelengths or pretreatment to effect photobleaching often resulted in reduced fluorescence, particularly for solid color samples, and allowed pigment identification. The examined samples were compared pairwise taking into account number, location, and intensity of absorption bands in their infrared spectra. The estimated discrimination power ranged from 97% for solid paint samples to 99% for metallic paint samples.
Article
Titanium dioxide (TiO2) is widely used in food products, which will eventually enter wastewater treatment plants and terrestrial or aquatic environments, yet little is known about the fraction of this TiO2 that is nano-scale, or the physical and chemical properties of TiO2 that influence its human and environmental fate or toxicity. Instead of analyzing TiO2 properties in complex food or environmental samples, we procured samples of food-grade TiO2 obtained from global food suppliers and then, using spectroscopic and other analytical techniques, quantified several parameters (elemental composition, crystal structure, size, surface composition) that are reported to influence environmental fate and toxicity. Another sample of nano-TiO2 that is generally sold for catalytic applications (P25) and widely used in toxicity studies, was analyzed for comparison. Food-grade and P25 TiO2 are engineered products, frequently synthesized from purified titanium precursors, and not milled from bulk scale minerals. Nano-sized materials were present in all of the food-grade TiO2 samples, and TEM showed that Samples 1-5 contained 35%, 23%, 21%, 17%, and 19% of nano-sized primary particles (diameter below 100 nm) by number, respectively (all primary P25 particles were < 100 nm). Both types of TiO2 aggregated in water with an average hydrodynamic diameter above 100 nm. Food-grade samples contained phosphorous (P), with concentrations ranging from 0.5 to 1.8 mg P/g TiO2. The phosphorous content in P25 was below ICP-MS detection limits. Presumably owing to a P-based coatings detected by XPS, the zeta potential of the food-grade TiO2 suspension in deionized water ranged from -10 to -45 mV around pH 7, and iso-electric point for food grade TiO2 (< pH 4) were significantly lower than that for P25. The presence of other elements in/on the TiO2 (Si content was 0.026%-0.062% and Al content was 0.0006%-0.810%) were also unique from P25 and would influence the environmental fate of TiO2. X-ray diffraction analysis confirmed the presence of anatase and/or rutile in the food-grade materials, and although the presence of amorphous TiO2 could not be ruled out, it is unlikely on the basis of Raman analysis. The food grade TiO2 was solar photo-active. Cationic dyes adsorbed more readily to food-grade TiO2 than P25, indicating very different potentials for interaction with organics in the environment. This research shows that food-grade TiO2 contains engineered nanomaterials with properties quite different from P25, which has previously been used in many eco-toxicity studies to date, and because food-grade TiO2 is more likely than P25 to enter the environment (i.e., potentially higher exposure levels) there is a need to design environmental (and human) fate and toxicity studies comparing food-grade to catalytic TiO2.
Article
A group of the late 12th–13th century Byzantine pottery glazes, mostly related to Zeuxippus Ware Type pottery from the Kuşadası Kadıkalesi/Anaia site in western Anatolia, was characterized non-destructively using Raman spectrometry. SEM–EDX was also used complementarily for the glaze characterization. The nature and composition of the glazes, firing conditions, aspects of colour formation and pigments used were discussed. The glazes were found to be lead-rich silicates, fired close to 700°C on the basis of the Si–O stretching peak maxima of the Raman spectra recorded at ∼920–980 cm–1, as also confirmed by SEM–EDX analysis. The polymerization index values calculated are between approximately 0.05 and 0.1. The use of biscuit-fired bodies prior to glaze application was suggested based on the results of SEM–EDX analysis. In particular, the detection of Naples yellow pigment variations on a locally produced pottery sample is quite significant, since the use of this type of pigment has hardly ever been reported between the Roman period and the Renaissance.
Article
The mass, IR- and NMR-spectra of 18 compounds were interpreted; one of these compounds has been15N-labelled. Fragmentation processes give evidence that azo- and hydrazone-tautomeres are present in the gaseous state. IR-and NMR-spectroscopic investigations show, that the phenyl-hydrazones as solids and in solution exist as bis chelated (Z)-isomers only. An approximately linear relationship is given between the chemical shifts of NH-Protons and pK B-and Hammett σ-values resp.
Article
Cobalt(II) phthalocyanine (CoPc), cobalt(II) tetrachloro phthalocyanine (CoPcCl4), cobalt(II) octachloro phthalocyanine (CoPcCl8) and cobalt(II) hexadecachloro phthalocyanine (CoPcCl16) are synthesized pure and characterized using elemental analysis, UV-visible, IR-spectroscopy, magnetic susceptibility, X-ray crystallography, and thermogravimetry. All four complexes have monoclinic structure with different crystal lattice constants. Broido's, Coats-Redfern and Horowitz-Metzger relations were employed to calculate the kinetic and activation parameters associated with thermal decomposition of the above complexes. The compounds are analyzed for kinetic parameters, activation energies for decomposition and the Arrhenious pre-exponential factors, in their pyrolysis. Using these factors and standard equations, thermodynamic parameters such as enthalpy, entropy and free energies are calculated. The activation energies are evaluated based on their electrical conductivity conducted over the temperature range 30–200°C. The electrical conductivities observed at 30°C are in the order CoPcCl16 > CoPcCl4 > CoPcCl8 > CoPc. The relevant electrical conductivity data are reported.
Article
The chemical composition of tattooing pigments has varied greatly over time according to available technologies and materials. Beginning with naturally derived plant and animal extracts, to coloured inorganic oxides and salts, through to the modern industrial organic pigments favoured in today's tattooing studios. The demand for tattooing is steadily growing as it gains cultural popularity and acceptance in today's society, but ironically, increasing numbers of individuals are seeking laser removal of their tattoos for a variety of reasons. Organic pigments are favoured for tattooing because of their high tinting strength, light fastness, enzymatic resistance, dispersion and relatively inexpensive production costs. Adverse reactions have been reported for some organic inks, as well as potential complications, during laser removal procedures stemming from the unintentional creation of toxic by-products. Currently, regulatory bodies such as the US Food and Drug Administration have not approved any coloured inks to be injected into the skin, and tattoo ink manufacturers often do not disclose the ingredients in their products to maintain proprietary knowledge of their creations. A methodology was established using micro-Raman spectroscopy on an animal model to correctly identify the constituents of a selection of modern, organic tattoo inks in situ or post procedure, within the skin. This may serve as a preliminary tool prior to engaging in Q-switched laser removals to assess the risks of producing potentially hazardous compounds. Likewise, the pigments responsible for causing adverse reactions in some patients may be quickly identified to hasten any corresponding treatment.
Article
Nanoparticles (NPs) are of similar size to typical cellular components and proteins, and can efficiently intrude living cells. A detailed understanding of the involved processes at the molecular level is important for developing NPs designed for selective uptake by specific cells, for example, for targeted drug delivery. In addition, this knowledge can greatly assist in the engineering of NPs that should not penetrate cells so as to avoid adverse health effects. In recent years, a wide variety of experiments have been performed to elucidate the mechanisms underlying cellular NP uptake. Here, we review some select recent studies, which are often based on fluorescence microscopy and sophisticated strategies for specific labelling of key cellular components. We address the role of the protein corona forming around NPs in biological environments, and describe recent work revealing active endocytosis mechanisms and pathways involved in their cellular uptake. Passive uptake is also discussed. The current state of knowledge is summarized, and we point to issues that still need to be addressed to further advance our understanding of cellular NP uptake.
Article
Various spectral methods (IR absorption and reflectance-absorption, Raman scattering and UV–Vis absorption) were used for investigations of a family of copper phthalocyanines in non-polarized and polarized light. The spectra of bulk and thin film samples were compared and discussed; an orientation of selected copper phthalocyanines in Langmuir–Blogdett layers and interaction between the phthalocyanine dyes with solid substrates were studied and discussed. Molecular arrangement of the molecular skeleton on the solid substrates was also evaluated. The presence of dye aggregates in the Langmuir–Blodgett layers was shown confirming the data obtained in concentrated solutions and in Langmuir layers.
Article
The purpose of this paper is to follow the influence of chlorine or fluorine substituents of phthalocyanine dyes on their spectroscopic, photothermal and photoelectric properties. Such influence is discussed in term of the resonance effects occurring in organic macrocycles. The domination of mesomeric effect was indicated due to the large enhancement of photocurrent created by the studied systems and other changes in spectroscopic and photothermal properties of the investigated phthalocyanines. The occurrence of steric effect was supported by the photothermal experiments. The differences between electronegative substituents of phthalocyanine dyes on photophysical properties of macromolecular systems are also discussed.
Article
Fluorescent background is a major problem in recoding the Raman spectra of many samples, which swamps or obscures the Raman signals. The background should be suppressed in order to perform further qualitative or quantitative analysis of the spectra. For this purpose, an intelligent background-correction algorithm is developed, which simulates manual background-correction procedure intelligently. It basically consists of three aspects: (1) accurate peak position detection in the Raman spectrum by continuous wavelet transform (CWT) with the Mexican Hat wavelet as the mother wavelet; (2) peak-width estimation by signal-to-noise ratio (SNR) enhancing derivative calculation based on CWT but with the Haar wavelet as the mother wavelet; and (3) background fitting using penalized least squares with binary masks. This algorithm does not require any preprocessing step for transforming the spectrum into the wavelet space and can suppress the fluorescent background of Raman spectra intelligently and validly. The algorithm is implemented in R language and available as open source software (). Copyright ?2009 John Wiley & Sons, Ltd.
Article
SummaryA patient with sarcoidosis who presented with a granulomatous tattoo reaction is described. Although tattoo granulomata usually represent a local hypersensitivity reaction to tattoo pigments, they can be a manifestation of systemic sarcoidosis. In this case the lesions were confined to the red areas of tattoos suggesting that tattoo sarcoid may be more than just an example of the Koebner response.
Article
Eighteen patients who developed cutaneous reactions to red tattoos were studied to identify the chemicals responsible for the reactions to modern red tattoo pigments. Biopsies from the tattoos were examined histologically and the chemical composition of the red pigments was analysed by X-ray microanalysis. A variety of metallic elements including aluminium, iron, calcium, titanium, silicon, mercury and cadmium were detected. Patch tests were performed to the relevant chemicals in nine cases, and only one patient reacted to mercury. This study demonstrates that although reactions to mercury still occur, other red dyes containing a variety of inorganic pigments may provoke a cutaneous inflammatory response.
Article
Disazoacetoacetanilides provide the most important classical organic pigments in the yellow shade area, especially for printing ink applications. As a first step in attempting to establish the colour and constitution relationships in this series of products, a number of disazo pigments were synthesised and their UV/visible spectral behaviour in solution investigated. PPP molecular orbital calculations, using a generalised set of parameters optimised previously for a series of monoazoacetoacetanilides and assuming that the compounds exist exclusively in bisketohydrazone tautomeric forms with planar molecular geometry, provided a good correlation between calculated and experimental λmax values for the principal absorption band, and in addition there was a reasonable qualitative agreement between molar extinction coefficients and the calculated oscillator strengths. The spectroscopic evidence for the bisketohydrazone form is discussed. The effect of rotation about the biphenyl link in C.I. Pigment Yellow 12 on the predicted spectroscopic properties was investigated using an empirical correction to the calculations.
Article
All three pigments crystallise in the triclinic system, space group P, and with one molecule in the unit cell so that all molecules have crystallographic Ci symmetry. The molecules exist in the bisketohydrazone tautomeric form. The intramolecular hydrogen bonding normally associated with this structural arrangement is observed, but there is no intermolecular hydrogen bonding. The molecules are not quite planar, but deviate from planarity by only a few degrees of torsional bond rotations. In each structure the molecules pack together in inclined interleaved stacks so that the ketohydrazonoarylamide groups lie above and below one another in antiparallel arrangements. The colour and technical performance of the pigments are discussed in relation to the structural details.
Article
Monoazoacetoacetanilides provide some of the most important classical organic pigments in the yellow to orange shade area for a range of applications. As a first step in attempting to establish the colour and constitution relationships in this series of products, a range of monoazoacetoacetanilides was synthesised and their UV/visible spectral behaviour in solution investigated. PPP molecular orbital calculations, using the generalised set of parameters approach, were refined by parameter optimisation to provide an excellent correlation between calculated and experimental λmax values for the principal absorption band, and in addition there was generally good qualitative agreement between molar extinction coefficients and the calculated oscillator strengths. The nature of the electronic excitation process is discussed in terms of the calculated changes in π-electron charge densities.
Article
Micrometre-sized aluminium particles are used as pigments in silver inks and for environmental reasons it is desirable to develop water-based formulations of such pigments. In waterborne coatings, however, aluminium is prone to react with water, with subsequent hydrogen gas evolution and loss of the silvery lustre. The protection against water of aluminium pigments by adsorption of either a nonionic or an anionic surfactant has been evaluated. Phosphate esters with different lengths of the hydrocarbon tail have been synthesised and tested, and were found to provide very effective protection of the pigments. Sodium dodecyl sulphate (SDS), on the other hand, was completely ineffective as inhibitor, even though the adsorption isotherm was about the same as for the structurally similar sodium dodecyl phosphate (SDP). This difference may be explained by formation of different types of complexes with the aluminium oxide surface. Outer-sphere complexes are suggested for SDS, whilst SDP can form more stable inner-sphere complexes. Tests with the non-surface active methyl phosphate as inhibiting agent gave insufficient protection, indicating that surface activity is crucial for the inhibition, and that the use of the phosphates as such is not enough to give proper protection. The work shows that amphiphilic compounds having phosphate as anchoring group are efficient in providing water resistance to aluminium pigments.
Article
Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system and, subsequently, enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO(2), and discusses the impact of the nanoscale fraction of TiO(2) entering the environment. The foods with the highest content of TiO(2) included candies, sweets, and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO(2) (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that, while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to wastewater treatment plants (WWTPs) deserves attention. A Monte Carlo human exposure analysis to TiO(2) through foods identified children as having the highest exposures because TiO(2) content of sweets is higher than other food products and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium-based white pigment used annually, testing should focus on food-grade TiO(2) (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).
Article
To our knowledge tattooing has never been thought of as a method of introducing nanoparticles (NPs) into the human body by the intradermal route, and as such it has never been a topic of research in nanotoxicology. The content of NPs in tattoo inks is unknown. To classify the particle sizes in tattoo inks in general usage. The particle size was measured by laser diffraction, electron microscopy and X-ray diffraction. The size of the pigments could be divided into three main classes. The black pigments were the smallest, the white pigments the largest and the coloured pigments had a size in between the two. The vast majority of the tested tattoo inks contained significant amounts of NPs except for the white pigments. The black pigments were almost pure NPs, i.e. particles with at least one dimension <100 nm. The finding of NPs in tattoo inks in general usage is new and may contribute to the understanding of tattoo ink kinetics. How the body responds to NP tattoo pigments should be examined further.
Article
Nanotoxicology studies require investigations of several physico-chemical aspects of the particle/body fluid interaction, here described by reviewing recent literature in the light of new experimental data. Current characterization mostly covers morphology and metric-related characteristics (form, chemical composition, specific surface area, primary particle size and size distribution), and is mandatory in any experimental study. To unveil toxicity mechanisms, several other physico-chemical properties relevant to (geno) toxicity need to be assessed, typically the release or quenching of radical/ROS (Reactive Oxygen Species), the presence of active metal ions, evidence of structural defects. Major tasks for physical chemists working on nanoparticles-induced genotoxicity are described with some examples: (i), Tailored preparation of the same material in different sizes; (ii) particle modification changing a single property at a time; and (iii) identification of appropriate reference materials. Phenomena occurring during the contact between nanoparticles and cellular media or biological fluids (dispersion, agglomeration/aggregation, protein adsorption) are discussed in relation to the surface properties of the nanoparticles considered.
Article
Tattooing practice is adopted worldwide and represents an important socio-cultural phenomenon, but, the injection into the skin of coloring agents as metals might pose a risk for allergies and other skin inflammations as well as for systemic diseases. In this context, 56 inks for tattooing purchased from 4 different supply companies were analyzed for metal concentration. Aliquots of pigments were microwave digested by nitric acid, fluoridric acid and hydrogen-peroxide and Al, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Sr and V were quantified by sector field inductively coupled plasma mass spectrometry. Limits of quantification varied from 0.07 ng/ml (Cd) to 10 ng/ml (Al and Fe); recoveries ranged from 92% (Cd and Sb) to 109% (Sr); within- and between-day precisions were 3.2% and 4.67% on average. The relative contribution of metals to the tattoo inks composition was highly variable between brands and colors, even in pigments with the same base color. Elements found as the main components of inks were as follows (in microg/g): Al, 1.59-5893; Ba, 0.058-1226; Cu, 0.076-31,310; Fe, 0.717-88,443; Sr, 0.174-36.4. Toxic metals as Cd, Mn, Pb, Sb and V were over the 1 microg/g in a few cases, while Hg was in traces. Among the allergenic metals, Cr was the highest (0.315-147 microg/g), followed by Ni (0.037-9.59 microg/g) and Co (0.0028-6.43 microg/g) then. On 56 tattoo inks, Cr, Ni and Co exceeded the safe allergological limit of 1 microg/g in 62.5%, 16.1% and 1.8% of cases, respectively.
Article
A review of past and present published works examining the interaction of polymeric dispersants with titania pigment particles is presented. Titania is the most important white pigments currently used in the world and its suspension properties are very important for consumer industries such as paints, papermaking and plastics; if aggregates are present, the end-use properties including gloss, opacity and storage stability will be highly affected. As polymeric dispersants are generally used to disperse titania pigment particles, it is very important to understand the interactions between the pigment particles and polymeric dispersants of varying functionality. Although, in principle, the adsorption of polymers onto titania pigment and influences on pigment dispersion and stabilisation are fairly known, it is nevertheless hardly possible to forecast the behaviour of a given polymeric dispersant in advance, unless to have a broad knowledge of the interaction occurring between pigment and dispersants and effect of dispersant structure upon adsorption. While only titania pigment is discussed, the issues raised may also apply to other mineral oxides such as alumina or zirconia.
Article
This work deals with the vibrational spectroscopy of p-hydroxyanisole (PHA) and p-nitroanisole (PNA) by means of quantum chemical calculations. The mid and far FT-IR and FT-Raman spectra were recorded in the condensed state. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) with the standard B3LYP/6-31G* method and basis set combination and were scaled using various scale factors which yield a good agreement between observed and calculated frequencies. The vibrational spectra were interpreted with the aid of normal coordinate analysis based on scaled density functional force field. The results of the calculations were applied to simulate infrared and Raman spectra of the title compounds, which showed excellent agreement with the observed spectra.
Article
The effects of exposure of human dermal fibroblasts to rutile and anatase TiO(2) nanoparticles are reported. These particles can impair cell function, with the latter being more potent at producing damage. The exposure to nanoparticles decreases cell area, cell proliferation, mobility, and ability to contract collagen. Individual particles are shown to penetrate easily through the cell membrane in the absence of endocytosis, while some endocytosis is observed for larger particle clusters. Once inside, the particles are sequestered in vesicles, which continue to fill up with increasing incubation time till they rupture. Particles coated with a dense grafted polymer brush are also tested, and, using flow cytometry, are shown to prevent adherence to the cell membrane and hence penetration of the cell, which effectively decreases reactive oxygen species (ROS) formation and protects cells, even in the absence of light exposure. Considering the broad applications of these nanoparticles in personal health care products, the functionalized polymer coating can potentially play an important role in protecting cells and tissue from damage.
Article
Some 170 organic pigments relevant to artist's paints have been collected from historic collections and modern manufacturers. The number includes multiples of the same pigment from different sources and comprises 118 different color indices (C.I.). All of them have been analysed with FTIR spectroscopy and 125 pigments (93 different C.I. No.s) of particular relevance to artist's paints have been characterised with Raman spectroscopy so far. The pigment collection encompasses the following pigment classes and subgroups: monoazo pigments represented by acetoacetic arylide yellow (hansa yellow), beta-naphthol, BON, naphthol AS and benzimidazolone; disazo pigments with disazo condensation, diarylide, bisacetoacetarylide, pyrazolone; azo-azomethin metal complex pigments; non-azo, polycyclic pigments such as phthalocyanines, diketopyrrolo-pyrroles (DPP), perylenes and perinones, quinacridones, isoindolinones, polycarbocyclic anthraquinones and dioxanines. The selection of references was based on availability (historic collections) and current use in 16 acrylic, alkyd and oil-based artist's paints, and it covers pigment colors PY yellow (27 C.I. No.s), PR red (38), PO orange (9), PB blue (8), PV violet (6), PG green (3) and PBr brown (2). Besides peak tables and spectra patterns, flow charts based on color, pigment class, group and individual color index are presented to help identification of unknowns and mixed paint samples. While Raman could isolate all different C.I. numbers, multiple references of the same C.I. from different sources could not be distinguished.
Article
A patient with sarcoidosis who presented with a granulomatous tattoo reaction is described. Although tattoo granulomata usually represent a local hypersensitivity reaction to tattoo pigments, they can be a manifestation of systemic sarcoidosis. In this case the lesions were confined to the red areas of tattoos suggesting that tattoo sarcoid may be more than just an example of the Koebner response.
Article
Eighteen patients who developed cutaneous reactions to red tattoos were studied to identify the chemicals responsible for the reactions to modern red tattoo pigments. Biopsies from the tattoos were examined histologically and the chemical composition of the red pigments was analysed by X-ray microanalysis. A variety of metallic elements including aluminium, iron, calcium, titanium, silicon, mercury and cadmium were detected. Patch tests were performed to the relevant chemicals in nine cases, and only one patient reacted to mercury. This study demonstrates that although reactions to mercury still occur, other red dyes containing a variety of inorganic pigments may provoke a cutaneous inflammatory response.
Article
Aluminium salts are used as the active antiperspirant agent in underarm cosmetics, but the effects of widespread, long term and increasing use remain unknown, especially in relation to the breast, which is a local area of application. Clinical studies showing a disproportionately high incidence of breast cancer in the upper outer quadrant of the breast together with reports of genomic instability in outer quadrants of the breast provide supporting evidence for a role for locally applied cosmetic chemicals in the development of breast cancer. Aluminium is known to have a genotoxic profile, capable of causing both DNA alterations and epigenetic effects, and this would be consistent with a potential role in breast cancer if such effects occurred in breast cells. Oestrogen is a well established influence in breast cancer and its action, dependent on intracellular receptors which function as ligand-activated zinc finger transcription factors, suggests one possible point of interference from aluminium. Results reported here demonstrate that aluminium in the form of aluminium chloride or aluminium chlorhydrate can interfere with the function of oestrogen receptors of MCF7 human breast cancer cells both in terms of ligand binding and in terms of oestrogen-regulated reporter gene expression. This adds aluminium to the increasing list of metals capable of interfering with oestrogen action and termed metalloestrogens. Further studies are now needed to identify the molecular basis of this action, the longer term effects of aluminium exposure and whether aluminium can cause aberrations to other signalling pathways in breast cells. Given the wide exposure of the human population to antiperspirants, it will be important to establish dermal absorption in the local area of the breast and whether long term low level absorption could play a role in the increasing incidence of breast cancer.