Screening for skin-sensitizing allergens among patients with clinically suspected allergic contact dermatitis

Quantification of p-Phenylenediamine in Hair Dyes and Health Risk Implications in the UAE: Describing Discordances Between Regulations and Real-Life Practices

Background

p-Phenylenediamine (PPD) has been used over the past five decades as a primary precursor in the production of oxidative hair dyes. Numerous health dangers are associated with the short- and long-term use of PPD, raising concerns about its safety. For instance, mounting data suggests that PPD is linked to dermatitis and allergy cases.

Objective

To quantify the PPD content in hair dyes by measuring the PPD concentration after mixing the ingredients of commercial hair dyes.

Methods

A total of 290 permanent hair dyes were tested. RP-HPLC-DAD analysis was performed to determine and quantify the PPD content.

Results

The estimated mean of the PPD limit was 0.89 (95% CI [0.81-0.96]). Of the 290 tested hair dyes, 7.2% (n = 21) exceeded the recommended PPD concentration after mixing. Significantly more hair dyes manufactured in India and China had a PPD content exceeding 2% after mixing compared to dyes from other regions (P = 0.001). Moreover, hair dyes manufactured in India and the UAE were more likely to have incomplete descriptions of the conditions of use and warnings on the label (P = 0.002).

Conclusion

The effectiveness of the current regulations relevant to these products should be reevaluated. Moreover, through the use of good manufacturing procedures (GMPs), research, and the reporting of adverse reactions, hair dyes should be subjected to better control and monitoring in terms of their safety and quality.

Toxic Ingredients in Personal Care Products: A Dermatological Perspective

Environmental dermatology is the study of how environmental factors affect the integumentary system. The environment includes natural and built habitats, encompassing ambient exposure, occupational exposures, and lifestyle exposures secondary to dietary and personal care choices. This review explores common toxins found in personal care products and packaging, such as bisphenols, parabens, phthalates, per- and poly-fluoroalkyl substances, p-phenylenediamine, and formaldehyde. Exposure to these toxins has been associated with carcinogenic, obesogenic, or proinflammatory effects that can potentiate disease. In addition, these compounds have been implicated as endocrine-disrupting chemicals that can worsen dermatological conditions such as acne vulgaris, or dermatitis. Certain pollutants found in personal care products are not biodegradable and have the potential to bioaccumulate in humans. Therefore, even short-term exposure can cause long-lasting issues for communities. The skin is often the first point of contact for environmental exposures and serves as the conduit between environmental toxins and the human body. Therefore, it is important for dermatologists to understand common pollutants and their acute, subacute, and chronic impact on dermatological conditions to better diagnose and manage disease.

The Association of Smoking with Contact Dermatitis: A Cross-Sectional Study

Contact dermatitis is a chronic inflammatory skin disorder with a highly variable prevalence worldwide. Smoking plays a crucial role in mediating inflammatory skin conditions such as contact dermatitis. The present study aimed to investigate the association between smoking status and contact dermatitis in the Saudi population. The patients in the present study were individuals older than 18 years who were diagnosed with contact dermatitis and received a patch test at the Department of Dermatology of King Saud University Medical City from March 2003 through February 2019. All patients were interviewed by phone to complete a specific pre-designed questionnaire to assess tobacco use or exposure history. The total number of enrolled patients in the study was 308 (91 males and 217 females), all with contact dermatitis. Data from the present study suggest that the prevalence of allergic contact dermatitis in smokers may be less than that in non-smokers. Moreover, the prevalence of irritant contact dermatitis in smokers is more significant than in non-smokers. Finally, left-hand contact dermatitis is significantly associated with smoking. Therefore, there is a strong association between smoking and irritant contact dermatitis, especially in the Saudi population, regarding the left hand. Further epidemiologic studies are needed to further explore the role of smoking in the occurrence of contact dermatitis and to explore the possible mechanisms.

Systematic review on skin adverse effects of important hazardous hair cosmetic ingredients with a focus on hairdressers

BACKGROUND

The burden of occupational hand eczema in hairdressers is high, and (partly strong) allergens abound in the hair cosmetic products they use.

OBJECTIVES

To systematically review published evidence concerning contact allergy to an indicative list of active ingredients of hair cosmetics, namely, p-phenylenediamine (PPD), toluene-2,5-diamine (PTD), persulfates, mostly ammonium persulfate (APS), glyceryl thioglycolate (GMTG), and ammonium thioglycolate (ATG), concerning the prevalence of sensitization, particularly in terms of a comparison (relative risk; RR) between hairdressers and non-hairdressers.

METHODS

Following a PROSPERO-registered and published protocol, eligible literature published from 2000 to February 2021 was identified, yielding 322 publications, and extracted in standardized publication record forms, also considering risk of bias.

RESULTS

Based on 141 publications, the contact allergy prevalence to PPD was 4.3% (95% CI: 3.8-4.9%) in consecutively patch tested patients. Other ingredients were mostly tested in an aimed fashion, yielding variable, and partly high contact allergy prevalences. Where possible, the RR was calculated, yielding an average increased sensitization risk in hairdressers of between 5.4 (PPD) and 3.4 (ATG). Additional evidence related to immediate-type hypersensitivity, experimental results, exposures, and information from case reports was qualitatively synthesized.

CONCLUSIONS

An excess risk of contact allergy is clearly evident from the pooled published evidence from the last 20 years. This should prompt an improvement in working conditions and product safety.

Study of P-Phenylenediamine (PPD) Concentrations after Hair Dye Mixing: A Call for Safety Reassessment

Para-phenylenediamine (PPD) is a chemical that is widely used in hair dyes. Multiple safety and regulatory agencies have categorized PPD as a potent sensitizer. In addition, PPD has carcinogenicity and genotoxicity attributes and, consequently, it is regulated at a maximal concentration of 2.0%. The aim of this study was to test whether the limit for PPD is surplus, and hence whether the consumer may be exposed to unnecessarily PPD levels. Experimentally, the analysis of PPD was performed using HPLC, where method validation and an inter-laboratory comparison test (ILC) were conducted to evaluate method performance. Thirty-three commercial products were analyzed, and five products were chosen to study the unconsumed PPD. Successfully, the implemented method confirmed its suitability and validity for the determination of PPD. For ILC results, PPD levels were 0.97 ± 0.04% and 0.92 ± 0.02%, quantified by our laboratory and an accredited laboratory, respectively. For all products, the initial concentration (T0) of PPD was lower than the regulatory limit. After 45 min, the content of PPD significantly reduced compared to T0. One product showed unconsumed PPD to be as high as 96% following the recommended dyeing time. In conclusion, the existence of high levels of unreacted PPD increases the likelihood of allergic events and elevates the risk of PPD-related chemicals. Collaborative efforts between industries, regulatory bodies, and health-related decision makers are deemed necessary to establish safe concentrations for PPD.

Patch test results in paediatric patients with atopic dermatitis in Laos

BACKGROUND

Dermatological services in Laos, South East Asia are limited mainly to the capital and patch testing is currently not available, so no data exists regarding the common cutaneous allergens in this population.

OBJECTIVES

The aim of this study was to document common allergens in paediatric patients with atopic dermatitis attending the allergy clinic in the capital, Vientiane.

PATIENTS/MATERIALS/METHODS

Fifty paediatric patients with atopic dermatitis were patch tested using TRUE Test® panels 1 to 3 (35 allergens). Readings were taken at Days 2 and 4.

RESULTS

Twenty-six positive patch tests were recorded on Day 4 in 15 children (30%). The most common allergens were: gold (18%), nickel (10%), formaldehyde (6%) and p-Phenylenediamine (6%). Other positive allergens were potassium dichromate (2%), cobalt dichloride (2%), Bronopol (2%), paraben mix (2%), fragrance mix 1 (2%) and neomycin (2%). The majority of the patients with positive reactions were female.

CONCLUSIONS

This study represents the first documented patch test results in the Lao population. It is hoped that these findings will help clinicians to advise the families of children with atopic dermatitis on common allergens to avoid and inform future work on contact dermatitis in this population.

Analysis of Epicutaneous Patch Test Results in Patients with Contact Dermatitis

Background:

Allergic contact dermatitis (ACD) is a delayed type of hypersensitivity from contact with a specific allergen to which the patients has developed a specific sensitivity. The aim of the study was to evaluate the results of epicutaneous patch testing with standard series of contact allergen in patients suspected to have ACD.

Methods:

355 cases of ACD were included in the study. Test substances were applied on the upper part of the patient’s back, on clinically uninvolved and untreated skin. All patients were free from therapy with oral antihistamines, steroids and immunosuppressants. The patch test was removed and reaction were evaluated after 48 h and 72 h. Grading of negative (-) to positive (+ to ++++) patch test was done according to the International Contact Dermatitis Research Group. Statistical data analysis was performed by using χ²–test.

Results:

Of the 355 cases, 146 patients were male (41.1%) and 209 were female (58.9%). The youngest patients in the study was 16 years of age and the oldest was 67 years of age. The commonest age group affected was 41-50 years. Hands were the most common site of involvement. The occupational character of skin lesions was find in 75 (21.1%). The most common positive reactions were recorded to nickel sulphate 99 (27.8%), cobalt chloride 46 (12.9%), thimerosal 31 (8.7%), colophony 23 (6.5%), carba mix 21 (5.9%), potassium dichromate 20 (5.6%), acid chromici 19 (5.3%), fragrance mix 18 (5%), balsam of Peru 13 (3.7%), formaldehyde 9 (2.5%), and other allergens 26 (7.3%). Females were significantly more likely to show a positive response to two or more allergens (p<0.05). There was no statistically significant impact of age, occupation and duration of disease on results of patch testing (p>0.05).

Conclusions:

Our results indicate that nickel sulphate, cobalt chloride and thimerosal are the most common allergens responsible for induction of ACD. These findings are crucial in the treatment, long term management, an education of patients with ACD.