p-Phenylenediamine and Risk of Sensitization in Children

Results of the patch tests with European baseline series in children: Five years of experience from a single center in Turkey and a review of the literature

BACKGROUND

Pediatric allergic contact dermatitis (ACD) is increasingly prevalent. Patch testing is the gold-standard diagnostic method.

AIMS

Our study aimed to identify common contact-sensitizing allergens in Turkish children.

PATIENTS/METHODS

We retrospectively analyzed the patch test results and characteristics of 191 pediatric patients [114 (59.7%) females, 77 (40.3%) males], who received the diagnosis of allergic contact dermatitis between 2015 and 2019.

RESULTS

The mean age of the patients was 12.2 years (range 4-18 years). Thirty-six (18.8%) of the patients in the study group had positive patch test outcomes with 56 positive allergens. Girls had a significantly higher rate of total positive patch test results than boys (75%/25%; p = 0.003, p < 0.05). The most frequent four allergens were nickel sulfate (n = 20, 10.4%), cobalt chloride (n = 6, 3.14%), p-phenylenediamine (n = 5, 2.61%), Methylchloroisothiazolinone/methylisothiazolinone (n = 5, 2.61%), respectively.

CONCLUSIONS

In our study, we discovered that in addition to the frequently encountered metal allergens such as nickel and cobalt, p-phenylenediamine and Methylchloroisothiazolinone/methylisothiazolinone sensitivities were frequent in the Turkish population. p-phenylenediamine sensitization can cause serious systemic dermatitis during the lifetime of children. We suggest that in Turkey personal care and hygiene products containing Methylchloroisothiazolinone/methylisothiazolinone should be legally regulated. Since childhood contact dermatitis may have an impact on the quality of life by influencing family and social life, suspected allergens should be detected as early as possible.

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.

Rhus semialata M. extract ameliorate para-phenylenediamine-induced toxicity in keratinocytes

para-Phenylediamine (PPD), a major component of hair dyeing ingredients, can induce allergenic sensitization and exert mutagenic, tumorigenic and cytotoxic effect. In this study, we determined the cytotoxic effect of PPD on human keratinocytes and evaluated the protective effect of Rhus semialata M. extracts (RSE) on PPD induced cytotoxicity for the first time. We observed that RSE is a strong inhibitory agent against PPD-induced toxicity in human keratinocytes. The results indicated that RSE pretreatment significantly could suppress PPD induced cytotoxic effects, including decrease of cell viability, accumulation in subG1 phase of cells, and relocation of phosphatidylserine on keratinocytes. Also, we found that PPD caused cytotoxicity was associated with mitochondrial membrane potential loss and subsequent activation of caspase and PARP degradation. However, pretreatment of RSE showed preventive activities against PPD induced mitochondrial membrane potential loss and ROS production in keratinocytes. In conclusion, the results of present study suggest that RSE was able to protect the skin from several cytotoxic effects of PPD and could be a meaningful material in many industries using PPD.

Facile synthesis of oligo anilines as permanent hair dyes: how chemical modifications impart colour and avoid toxicity

Chemical modification of the hair dye para-phenylenediamine results in colors that avoid in situ oxidation and toxicity.