Toxic potential assessment of hair dye developer 2,4,5,6-tetraaminopyrimidine sulfate exposed under ambient UVB radiation.

Synthetic cosmetics, particularly hair dyes, are becoming increasingly popular among people of all ages and genders. 2,4,5,6-tetraaminopyrimidine sulfate (TAPS) is a key component of oxidative hair dyes and is used as a developer in several hair dyes. TAPS has previously been shown to absorb UVB strongly and degrade in a time-dependent manner, causing phototoxicity in human skin cells. However, the toxic effects of UVB-degraded TAPS are not explored in comparison to parent TAPS. Therefore, this research work aims to assess the toxicity of UVB-degraded TAPS than TAPS on two different test systems, that is, HaCaT (mammalian cell) and Staphylococcus aureus (a bacterial cell). Our result on HaCaT has illustrated that UVB-degraded TAPS is less toxic than parent TAPS. Additionally, UVB-exposed TAPS and parent TAPS were given to S. aureus, and the bacterial growth and their metabolic activity were assessed via CFU and phenotype microarray. The findings demonstrated that parent TAPS reduced bacterial growth via decreased metabolic activity; however, bacteria easily utilized the degraded TAPS. Thus, this study suggests that the products generated after UVB irradiation of TAPS is considered to be safer than their parent TAPS.

Acid Orange 3.

The Expert Panel for Cosmetic Ingredient Safety reviewed updated information that has become available since their original assessment from year 2000, along with updated information regarding product types, and frequency and concentrations of use, and reaffirmed their original conclusion that Acid Orange 3 is safe for use in hair dye formulations at concentrations <.2%.

HC Yellow 5.

The Expert Panel for Cosmetic Ingredient Safety reviewed updated information that has become available since their original assessment from 2007, along with updated information regarding product types, and frequency and concentrations of use, and reaffirmed their original conclusion that HC Yellow 5 is safe as a hair dye ingredient in the practices of use and concentration as described in this report.

Toxic effects of Arianor Ebony hair dye on human cells.

To evaluate the risks of hair dye exposure, we investigated cellular and molecular effects of Arianor Ebony dye, which is a mixture of azo and anthraquinone dyes, used in the composition of the black color. Cytotoxicity, genotoxicity, and gene expression of relevant molecules of apoptotic and oxidative stress mechanisms were investigated in HepG2 cells exposed to Arianor Ebony. Results showed that the dye did not induce cytotoxicity to exposed cells at a concentration up to 50 µg/mL compared to the negative control. However, genotoxic assays indicated that the dye was able to damage the genetic material at a concentration of 25 µg/mL, with induction factor values of exposed cells two- to five-fold higher than those recorded for the negative control. Moreover, the lowest observed effect concentration was 12.5 µg/mL. For gene expression, relevant changes were observed in cytochrome c and caspase 9, which decreased in cells incubated with the dye in a dose-dependent manner when compared with the negative control. In parallel, the expression of genes for antioxidant enzymes was increased in exposed cells, suggesting the presence of metabolic routes that protect cells against the toxic effect of the dye, avoiding exacerbated cellular death. Results suggested that the dye disrupted cellular homeostasis through mitochondrial dysfunction, which may be hazardous to human health. Thus, further investigations are necessary to deeply understand the mechanisms of action of the dye, considering its toxic potential found in our ex vivo assays.

Do hairdressers comprise a high risk group for genotoxicity? A systematic review.

BACKGROUND AND OBJECTIVES: Nowadays, hair dye products are widely used for aesthetic purposes, in which it generates chemical exposure to customers and, mainly, hairdressers. The aim of this systematic review was designed to elucidate the following question: are hair dye products able to induce DNA damage in hairdressers? METHODS: Studies were included in our analyses if they met the following criteria: (1) studies measuring genetic damage in vivo; (2) studies published in English; (3) studies that provided data clearly presented in scientific standards. RESULTS: Full manuscripts from 13 studies were carefully selected in this setting. Our results demonstrate that hair dye products may contain chemical agents able to induce DNA strand breaks or chromosome damage since the majority of studies demonstrated positive findings for genotoxicity. A total of 7 studies (out of 13) had strong or moderate rates in the quality assessment. The type of genotoxicity assay and sample selection criteria time influenced the outcome. CONCLUSION: In summary, our results reveal that hairdressers are occupationally exposed to genotoxic agents. Such findings are very important for protecting these professionals who are continuously exposed to chemicals for long periods.

Genotoxicity of oxidative hair dye precursors: A systematic review.

This systematic review, conducted according to the PRISMA guidelines, focuses on genotoxicity of oxidative hair dye precursors. The search for original papers published from 2000 to 2021 was performed in Medline, Web of Science, Cochrane registry, Scientific Committee on Consumer Safety of the European Commission and German MAK Commission opinions. Nine publications on genotoxicity of p-phenylenediamine (PPD) and toluene-2,5-diamine (p-toluylenediamine; PTD) were included, reporting results of 17 assays covering main genotoxicity endpoints. PPD and PTD were positive in bacterial mutation in vitro assay, and PPD tested positive also for somatic cell mutations in the Rodent Pig-a assay in vivo. Clastogenicity of PPD and PTD was revealed by in vitro chromosomal aberration assay. The alkaline comet assay in vitro showed DNA damage after PPD exposure, which was not confirmed in vivo, where PTD exhibited positive results. PPD induced micronucleus formation in vitro, and increased micronucleus frequencies in mice erythrocytes following high dose oral exposure in vivo. Based on the results of a limited number of data from the classical genotoxicity assay battery, this systematic review indicates genotoxic potential of hair dye precursors PPD and PTD, which may present an important health concern for consumers and in particular for professional hairdressers.

Dermal exposure and hair dye: Assessing potential bladder cancer risk from permanent hair dye.

Hair dye products include a range of chemicals, depending on the type and color. A common primary intermediate compound used to achieve the permanent effect of hair dye is para-phenylenediamine (PPD). 4-aminobiphenyl (4-ABP) has reportedly been found as a trace contaminant (presumably from the para-phenylenediamine [PPD] ingredient) in consumer permanent hair dye. While several regulatory agencies have designated 4-ABP as a human bladder carcinogen based on evidence in humans and experimental animals, only the Office of Environmental Health Hazard Assessment (OEHHA) have established a cancer risk value for 4-ABP of 0.03 µg/day based on liver tumors developed in mice. A hypothetical dermal risk assessment was performed to estimate the bladder cancer risk associated with exposure to 4-ABP from personal use of permanent hair dye potentially containing incidental 4-ABP. Previously published laboratory analyses characterizing 4-ABP concentrations in consumer hair dyes indicate the concentrations can range from below the limit of detection to 8120 ppb. Precautionary estimates of human scalp surface area, maximum skin adherence, hair dye retention factor, and percent dermal absorption were used to estimate the daily systemic exposure doses (SEDs) from dermal application of hair dye. The estimated SEDs ranged from 0.05 to 3000 pg/day. A margin of safety (MOS) was calculated as the ratio of the NSRL to the SED and ranged from 10 to 570,000. The results of this study suggest that there is no indication of increased risk of bladder cancer in humans from exposure to 4-ABP in consumer hair dye, especially as it is extremely unlikely that a consumer would use permanent hair dye on a daily basis (as this assessment models).

Pre- and postnatal maternal hair dye use and risk of wheeze and asthma in 5-year-old Japanese children: the Kyushu Okinawa Maternal and Child Health Study.

The present study investigated the association between pre- and postnatal maternal hair dye use and the risk of wheeze and asthma in Japanese children aged 5 years. Study participants were 1199 mother-child pairs. Information on the variables under study was obtained using repeated questionnaires completed by parents. Prenatal maternal hair dye use was associated with an increased risk of current wheeze and ever doctor-diagnosed asthma; the adjusted odds ratios (ORs) (95% confidence intervals [CIs]) were 1.44 (1.02-2.02) and 1.51 (1.00-2.25), respectively. Postnatal maternal hair dye use was related to the risk of doctor-diagnosed asthma; the adjusted OR (95% CI) was 1.58 (1.03-2.40). Children who were exposed to maternal hair dye use both prenatally and postnatally had an increased risk of childhood current wheeze and ever doctor-diagnosed asthma; the adjusted ORs (95% CIs) were 1.59 (1.03-2.42) and 1.76 (1.06-2.88), respectively. Our findings suggest that perinatal maternal hair dye use is associated with the risk of wheeze and asthma in children.

Amended Safety Assessment of Persulfates as Used in Cosmetics.

The Expert Panel for Cosmetic Ingredient Safety (Panel) reassessed the safety of 3 persulfate ingredients, which function as oxidizing agents in cosmetic products. The Panel reviewed relevant data relating to the safety of these ingredients and concluded that Ammonium, Potassium, and Sodium Persulfate are safe as used as oxidizing agents in hair colorants and hair lighteners designed for brief discontinuous use followed by thorough rinsing from the hair and skin. The Panel also concluded that the available data are insufficient for determining the safety of these persulfates in leave-on products and dentifrices.

Hair Dye Ingredients and Potential Health Risks from Exposure to Hair Dyeing.

Given the worldwide popularity of hair dyeing, there is an urgent need to understand the toxicities and risks associated with exposure to chemicals found in hair dye formulations. Hair dyes are categorized as oxidative and nonoxidative in terms of their chemical composition and ingredients. For several decades, the expert panel's Cosmetic Ingredient Review (CIR) has assessed the safety of many of the chemicals used in hair dyes; however, a comprehensive review of hair dye ingredients and the risk of exposure to hair dyeing has not been documented. Herein, we review the safety of the various chemicals in oxidative and nonoxidative hair dyes, toxicities associated with hair dyeing, and the carcinogenic risks related to hair dyeing. While many compounds are considered safe for users at the concentrations in hair dyes, there are conflicting data about a large number of hair dye formulations. The CIR expert panel has ratified a number of coloring ingredients for hair dyes and banned a series of chemicals as carcinogenic to animals and unsafe for this application. The use of these chemicals as raw materials for producing hair dyes may result in the synthesis of other contaminants with potential toxicities and increased risk of carcinogenesis. It is an open question whether personal or occupational hair dyeing increases the risk of cancer; however, in specific subpopulations, a positive association between hair dye use and cancer occurrence has been reported. To address this question, a better understanding of the chemical and mechanistic basis of the reported toxicities of hair dye mixtures and individual hair dye ingredients is needed. It is anticipated that in-depth chemical and systems toxicology studies harnessing modern and emerging techniques can shed light on this public health concern in the future.

Para-phenylenediamine deteriorates oocyte quality by impairing mitochondrial function.

Several studies demonstrate that para-phenylenediamine (PPD) is often added to permanent oxidative hair dyes. Sub-chronic topical exposure to PPD in male rats damages their testicular function; however, little is known about the effects of PPD exposure on the female reproductive system, especially on oocyte quality. In this study, we found that PPD can affect the meiotic capacity of oocytes and their fertilization potential. In particular, PPD can damage the spindle/chromosome structure and prevent oocytes from developing and maturing normally. Furthermore, PPD exposure compromised the dynamics of cortical granules and their component, ovastacin. In addition to the protein level of Juno, the sperm receptors on the egg membrane, were substantially impaired in PPD-administered oocytes, thus leading to fertilization failure. Finally, we found that PPD exposure resulted in abnormal mitochondrial function, which led to oocyte degeneration, apoptosis, and increased ROS levels. Altogether, our study illustrates that mitochondrial dysfunction and redox perturbation are the major causes of the poor quality of oocytes exposed to PPD.

Impact of two commercially available hair dyes on germination, morpho-physiology, and biochemistry of Cicer arietinum L. and cytotoxicity study on Allium cepa L. root tip.

Contamination of agricultural land and surface water by personal care products and pharmaceutical constituents is a potential environmental threat. The active ingredients of personal care products are life-threatening for users. Present work highlighted the efficacy of the different components of two commercially available hair dyes (synthetic and herbal) on germination, morpho-physiological, biochemical parameters of Cicer arietinum, and cytotoxicity study by Allium cepa root tip. Different treatments such as T1 (control), T2 (cream colour rich), T3 (developer) (The ingredients T2 and T3 are from the same hair dye), T4 (an equal mixture of T2 and T3), and T5 (herbal dye) were considered to run this experiment. The results revealed that all the treatments improve germination with respect to control. Moreover, GSI data suggests that T2 showed the highest germination speed and T3 showed the lowest with respect to other treatments. But root lengths are severely affected by the treatments T3 (100% developer of synthetic hair dye), T4 (an equal mixture of T2 (100% cream colour rich) and T3), and T5 (100% herbal hair dye) with respect to control.T2 also showed the highest root tolerance of all treatments other than control. Similarly, one-way ANOVA results revealed that both fresh weight of roots (p ≤ 0.03) and shoots (p ≤ 0.03) are statistically significant among the different treatments. Moreover, both proline and root ion leakage are higher in the treatment T4 and T5 with respect to control, respectively. On the other hand, the cytotoxicity study highlighted that treatments T3 and T4 showed a higher level of aberration and significantly lower mitotic index compared to treatment T5. Therefore, finally, it may be concluded that both individual and combined forms of ingredients of hair dyes are toxic with respect to cell division and overall plant growth and development.

Investigations on detoxification mechanisms of novel para-phenylenediamine analogues through N-acetyltransferase 1 (NAT-1).

Para-phenylenediamine (PPD) is one of the most used chemicals in oxidative hair dyes. However, its use has been associated with adverse effects on health, including contact dermatitis and other systemic toxicities. Novel PPD derivatives have been proposed as a safer replacement for PPD. This can be achieved if these molecules minimally permeate the skin and/or are easily metabolised by enzymes in the skin (e.g., N-acetyltransferase-1 (NAT-1)) into innocuous compounds before gaining systemic entry. This study investigated the detoxification pathway mediated by NAT-1 enzymes on 6 synthesized PPD analogues (namely, P1-P6) with different chemical properties, to study the role of functional groups on detoxification mechanisms in HaCaT skin cells. These compounds were carefully designed with different chemical properties (whereby the ortho position of PPD was substituted by nucleophile and electrophile groups to promote N-acetylation reactions, metabolism and clearance). Compounds P2-P4 N-acetylated at 54-49 nmol/mg/min, which is 1.6 times higher than N-acetylation of PPD, upregulated NAT-1 activity from 8-7% at 50 µM to 22-11% at 100 µM and showed 4 times higher rate of elimination (k equal to 0.141 ± 0.016-0.124 ± 0.01 h-1) and 3 times faster rate of clearance (0.172 ± 0.007-0.158 ± 0.005 h-1mgprotein-1) than PPD (0.0316 ± 0.0019 h-1, 0.0576 ± 0.003 h-1mg protein-1, respectively). The data suggest that nucleophile substituted compounds detoxify at a faster rate than PPD. Our metabolic and detoxification mechanistic studies revealed significantly higher rates of N-acetylation, NAT-1 activity and higher detoxification of P2-P4 in keratinocytes, suggesting the importance of nucleophilic groups at the ortho position in PPD to reduce toxicity of aniline-based dyes on human skin cells.

Associations of hair dye and relaxer use with breast tumor clinicopathologic features: Findings from the Women's circle of Health Study.

BACKGROUND: Building upon our earlier findings of significant associations between hair dye and relaxer use with increased breast cancer risk, we evaluated associations of select characteristics of use with breast tumor clinicopathology. METHODS: Using multivariable-adjusted models we examined the associations of interest in a case-only study of 2998 women with breast cancer, overall and stratified by race and estrogen receptor (ER) status, addressing multiple comparisons using Bonferroni correction. RESULTS: Compared to salon application of permanent hair dye, home kit and combination application (both salon and home kit application) were associated with increased odds of poorly differentiated tumors in the overall sample. This association was consistent among Black (home kit: OR 2.22, 95 % CI: 1.21-5.00; combination: OR 2.46, 95 % CI: 1.21-5.00), but not White women, and among ER+ (home kit: OR 1.47, 95 % CI: 0.82-2.63; combination: OR 2.98, 95 % CI: 1.62-5.49) but not ER-cases. Combination application of relaxers was associated with increased odds of tumors >2.0 cm vs. <1.0 cm (OR = 1.82, 95 % CI: 1.23-2.69). Longer duration and earlier use of relaxers and combination application of permanent hair dyes and relaxers were associated with breast tumor features including higher tumor grade and larger tumor size, which often denote more aggressive phenotypes, although the findings did not maintain significance with Bonferroni correction. CONCLUSIONS: These novel data support reported associations between hair dye and relaxer use with breast cancer, showing for the first time, associations with breast tumor clinicopathologic features. Improved hair product exposure measurement is essential for fully understanding the impact of these environmental exposure with breast cancer and to guide risk reduction strategies in the future.

Influence of cosmetic hair treatments on hair of methamphetamine abuser: Bleaching, perming and coloring.

Various cosmetic hair manipulations are known to interfere with the drug of abuse concentrations in hair. It is important to know the effects of cosmetic hair treatments as they may cause false-positive or false-negative results. The article aimed to investigate the effect of bleaching, perming, and dyeing treatment on the hair of methamphetamine（MA）abusers. The research results show that during the bleaching treatment, the content of MA in the hair is positively correlated with the degree of the treatment. Bleaching caused strong chemical degradation on MA, while perming exerted more a leaching out effect. Temporary dyes in single applications had only little effects on MA, Semi-permanent dyes can penetrate into the hair and exert a stronger matrix effect. The effect of permanent hair dye on the content of MA in hair mainly depends on the concentration of hydrogen peroxide.

Assessment of the compounds formed by oxidative reaction between p-toluenediamine and p-aminophenol in hair dyeing processes: Detection, mutagenic and toxicological properties.

Previous studies have demonstrated the presence of precursors and coupling agents in wastewater from hair dyeing processes. The complex reaction involved in the oxidation of these compounds can generate extremely hazardous sub-products, leading to an increase in the mutagenicity and toxicity of wastewater. Without proper treatment, this highly toxic wastewater may find its way into the drinking water treatment plant. The present work aimed to investigate the main products generated after the oxidation reaction involving p-toluenediamine (PTD) and p-aminophenol (PAP) - precursors that widely used in the composition of commercial permanent hair dyes, under experimental conditions close to the routine hair dyeing process (in the presence and absence of hydrogen peroxide in ammoniacal medium), using spectroscopic techniques. The study also investigated the mutagenicity and toxicity of the products formed in the hairdressing wash water and conducted detection analysis to determine the presence of the precursors and Bandrowski's Base Derivative (BBD) in samples of wastewater, surface and drinking water using HPLC-DAD and linear voltammetry techniques. Based on this investigation, we identified several PTD and PAP self-oxidation products and eleven sub-products derived from the reaction between PTD and PAP. Assays conducted using Salmonella typhimurium YG1041, with and without activation-induced rat liver metabolism (S9), indicated mutagenicity of the reaction products in concentrations above 10.0 µg µL-1. The concentrations of PTD, PAP, and several reactions and oxidation products of these precursors were detected in wastewater and water samples.

Analysis of mutagenic components of oxidative hair dyes with the Ames test.

Oxidative hair dyes consist of two components (I and II) that are mixed before use. Aromatic amines in component I and their reaction with hydrogen peroxide after mixing them with component II have been of primary concern. In addition, two in vitro genotoxicity assays are still required for the approval of the final products of oxidative hair dyes in China, and the substance in the oxidative hair dye that causes the high rate of positive results in genotoxicity tests, especially the Ames test, has not been fully elucidated. In this study, we analyzed the formulation of 55 different oxidative hair dyes from 7 color series and performed Ames tests in the strain TA98 with the S9 mix (oxidative hair dyes No. 1-30) and in strain TA97a without the S9 mix (oxidative hair dyes No. 31-55). We found that toluene-2,5-diamine sulfate (2,5-diaminotoluene sulfate, DATS) in component I may be the cause of mutagenicity in TA98, and hydrogen peroxide in component II may be the cause of mutagenicity in TA97a, and their positive concentrations were consistent with those that we calculated from Ames tests. The results suggest that the positive results for the oxidative hair dye in the Ames test were inevitable because of the existence of DATS in component I and of hydrogen peroxide in component II. Therefore, we should carry out safety assessments on each raw material and carry out risk assessments on the final products of oxidative hair dyes instead of genotoxicity tests in China.

Demonstration of the first-pass metabolism in the skin of the hair dye, 4-amino-2-hydroxytoluene, using the Chip2 skin-liver microphysiological model.

We used TissUse's HUMIMIC Chip2 microfluidic model, incorporating reconstructed skin models and liver spheroids, to investigate the impact of consumer-relevant application scenarios on the metabolic fate of the hair dye, 4-amino-2-hydroxytoluene (AHT). After a single topical or systemic application of AHT to Chip2 models, medium was analysed for parent and metabolites over 5 days. The metabolic profile of a high dose (resulting in a circuit concentration of 100 µM based on 100% bioavailability) of AHT was the same after systemic and topical application to 96-well EpiDerm™ models. Additional experiments indicated that metabolic capacity of EpiDerm™ models were saturated at this dose. At 2.5 µM, concentrations of AHT and several of its metabolites differed between application routes. Topical application resulted in a higher Cmax and a 327% higher area under the curve (AUC) of N-acetyl-AHT, indicating a first-pass effect in the EpiDerm™ models. In accordance with in vivo observations, there was a concomitant decrease in the Cmax and AUC of AHT-O-sulphate after topical, compared with systemic application. A similar alteration in metabolite ratios was observed using a 24-well full-thickness skin model, EpiDermFT™, indicating that a first-pass effect was also possible to detect in a more complex model. In addition, washing the EpiDermFT™ after 30 min, thus reflecting consumer use, decreased the systemic exposure to AHT and its metabolites. In conclusion, the skin-liver Chip2 model can be used to (a) recapitulate the first-pass effect of the skin and alterations in the metabolite profile of AHT observed in vivo and (b) provide consumer-relevant data regarding leave-on/rinse-off products.

Diatomite encapsulated AgNPs as novel hair dye cosmetics: Preparation, performance, and toxicity.

Naturally-occurring diatomite has been successfully utilised as a unique encapsulating material to obtain a highly dispersed suspension of uniformly-sized silver nanoparticles (AgNPs). Plant derived gallic acid was used as the reducing and capping agent. High-resolution scanning and transmission electron microscopy results confirmed the attachment of AgNPs on the surface of diatom frustule and maintained an excellent dispersion stability against particle aggregation. The AgNPs obtained were employed for the colouration of bleached human hair owing to the local surface plasmonic absorption (LSPR) of the AgNPs. The effects of Ag/diatomite concentration, dyeing pH, temperature and time on the produced colour were investigated. Hair fibres treated under optimised conditions display good colour fastness toward solar radiation. The morphology and chemical composition of AgNP-dyed hair were determined by energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses. The biocompatibility of the Ag/diatomite composite, AgNPs, and the dyebaths were confirmed by in vitro acute dermal and ocular toxicity tests. The diatomite supporting AgNPs therefore hold good promise and enormous potential to be exploited for sustainable dyeing of human hair.

Development of novel alternative hair dyes to hazardous para-phenylenediamine.

Most of the permanent hair dye products contain p-phenylenediamine (PPD), a well-known skin sensitizer. PPD may cause cutaneous reactions and leads to allergic contact dermatitis (ACD), a condition with major medical and financial repercussions. Hair dye-induced ACD represents a growing concern both for consumers and the cosmetics industry. In this study we introduced novel side chains on the PPD molecule with the goal of overcoming the hazard potential of PPD. Our strategy relies on the replacement of the colorless PPD with new, larger and intrinsically colorled PPD derivatives to reduce dermal penetration and thus the skin sensitization potential. We synthesized two oligomers with bulky side-chains, which displayed 7-8 times lower cytotoxicity than PPD, a significantly weaker sensitization potential (22.0 % and 23.8 % versus 55.5 % for PPD) in the Direct Peptide Reactivity Assay, minimal cumulative penetration through excised skin and an intrinsic ability to colour and preserve the nuance when applied on bleached hair. The lower skin permeation and sensitizing potential are absolutely crucial and give a clear advantage of our products over other standards. These novel PPD hair dyes show significantly less hazard potential than PPD and may, upon further risk assessment studies, replace PPD in consumer care products.