hair dyes are perhaps among the most commonly used cosmetics by elderly and the young alike - for concealing gray hair by the former or just for a fashion statement by the latter .
the popularity of hair colouring can be gauged from the fact that the median age for debut was 16 years and nearly 75% of women and 18% of men had dyed their hair at some point in their lives according to a danish population - based study .
this rising trend of hair colouring has resulted in an increased prevalence of hair dye - associated adverse effects accounting for 5.3% of danish persons who dyed their hair .
similarly , 42% of the respondents reported adverse reactions from use of hair dyes and the mean age of hair dye debut was 27 years in an indian study .
hair dyes include a variety of coloring agents such as 2,7-naphthalenediol , 2-aminomethyl - p - aminophenol hydrochloride , 2-chloro - p - phenylenediamine , n - phenyl - p - phenylenediamine , and o - aminophenol , p - aminophenol .
although all these agents can cause allergic contact reactions , p - phenylenediamine ( ppd ) remains the most commonly implicated agent for the contact sensitivity .
it is an effective compound for hair dyes due to its low molecular weight , high protein- binding capacity , and ability to penetrate the hair shaft .
apart from being a common constituent in varying concentrations of nearly 70% of the hair colorants available worldwide , it is also present in dyes for henna tattoos , textiles , leather and fur , and black rubbers .
being a member of 1,4-substituted benzenes , it cross - reacts with para - amino benzoic acid ( paba ) , sulphonamides , para - amino salicylic acid , ester anesthetics , thiazides , sesquiterpene - lactone mix , and azo dyes .
it is a potent contact sensitizer even in low concentration and considered a best indicator and useful patch test screening allergen for hair dye dermatitis .
the reported prevalence of positive patch test reactions to ppd among dermatitis patients is 4.4% in asia , 4.1% in europe , 6.0% in north america , and 11.5% in india .
the clinical features of hair dye dermatitis vary from mild contact dermatitis localized to one body site ( hand dermatitis ) or disseminated generalized dermatitis to severe life - threatening complications such as contact urticaria / angioedema , rhinitis / bronchospasm / asthma , and renal toxicity .
the most common clinical presentations include contact dermatitis localized to sites of contact or photoexposed skin , periorbital dermatitis , airborne contact dermatitis , hand dermatitis , and rarely erythema multiforme - like lesions . in this pilot study
, we present our clinico - epidemiological observations and patch test results of ppd contact sensitivity in patients suspected to have hair dye dermatitis .
eighty ( m : f 47:33 ) consecutive patients suspected to have hair dye allergy were enrolled for the study after obtaining informed consent .
patients having acute dermatitis were patch tested after control of their dermatitis , when they were off systemic corticosteroids or the dose of prednisolone was < 20 mg / day .
details about age , gender , occupation , personal or family history of atopy ( nasobronchial allergy , asthma , childhood eczema ) , use of hair dye and its duration , onset , duration , and distribution of dermatitis were noted .
the enrolled patients were patch tested by finn chambers method with indian standard patch test series including ppd ( 1.0% pet ) recommended by contact dermatitis and occupational dermatoses forum of india .
patches were applied on the upper back and the patients were asked to return for results after 48 hrs ( d2 ) and 72 hrs ( d3 ) .
the results were graded according to the international contact dermatitis research group criteria . only reactions persisting on d3 were considered positive for final analysis .
side effects such as adhesive tape reaction , discomfort and itching , flare of dermatitis , angry back phenomenon , active sensitization , and pigment alteration at test site , when they occurred , were recorded .
the study included 47 ( 58.8% ) males aged between 19 and 74 years and 33 ( 41.2% ) females aged between 18 to 74 years .
the majority , that is , 57 ( 71% ) patients were older than 40 years , while whereas 23 ( 29% ) were younger than 40 years , the youngest being a 19-year - old male .
forty six ( 57.5% ) patients were from an urban background and 34 ( 42.5% ) patients belonged to a rural background . among the males , 21 ( 44.7% ) were office goers , 9 ( 19.1% ) shopkeepers , and 6 ( 12.7% ) defence personnel . among females 30 ( 90.9% ) were housewives and 3 ( 9.09% ) were students .
the duration of hair dye usage varied from less than one month in 11 ( 13.8% ) to more than three years in 17 ( 21.2% ) patients .
other 52 ( 65% ) patients were using hair dyes for variable period of 1 month to 3 years .
the duration of dermatitis varied from < 1 month in 11 ( 13.8% ) patients and > 1 year in 27 ( 33.7% ) patients ; forty - two ( 52.5% ) patients had dermatitis between one month and one year .
clinically , characteristic acute ( erythematous , edematous , oozy , crusted eczematous plaques ) , subacute and chronic dermatitis ( hyperpigmented , lichenified eczematous lesions ) involving multiple sites such as scalp , scalp margins , forehead , eyelids , beard , neck , upper back , and/or hands was observed in all cases .
additionally , the most common patterns of hair dye dermatitis observed were contact dermatitis localized to scalp and/or scalp margins in 49 , followed by dermatitis of face ( including beard and periorbital skin ) and neck in 23 and hands and/or feet in 12 patients , respectively .
other patterns observed were airborne contact dermatitis in 9 , hand dermatitis in 5 , eyelid dermatitis in 4 , and discoid dermatitis and disseminated dermatitis in 1 ( 1.85% ) patient each .
one patient had generalized diffuse dermatitis and another patient showed erythema multiforme - like lesions .
none of the patients had followed the manufacturer 's instructions to perform sensitivity testing prior to applying the hair dye .
baseline characteristics of the patients studied only 54 ( 67.5% ) patients comprising 33 ( 61% ) males and 21 ( 39% ) females aged between of 19 and 74 years showed positive results to patch testing with ppd .
eight of these patients also showed positive patch test reaction to other allergens ; fragrance mix in 5 , thiuram mix in 3 , and paraben mix and colophony in 1 patient each .
thirty ( 55.5% ) patients belonged to urban populations and 24 ( 44.5% ) patients were from rural background .
the common clinical patterns noted were : ( a ) dermatitis localized to the scalp , face , neck or hands , ( b ) airborne dermatitis , ( c ) chronic actinic dermatitis ( actinic reticuloid ) , ( d ) generalized diffuse dermatitis , and ( e ) erythema multiforme - like dermatitis [ figures 1 to 5 ] .
ppd contact dermatitis localized to face , cheeks , nose , neck , and dorsal hands in photodistributed pattern ppd contact dermatitis localized to eyelids and periorbital skin ppd contact dermatitis localized over neck . she also had dermatitis involving the scalp skin ( a ) chronic actinic dermatitis ( actinic reticuloid ) due to ppd .
( b ) patch test shows 3 + reaction to ppd ppd induced erythema multiforme - like lesions over ( a ) upper back and ( b ) palms .
the use of hair colorants has increased exponentially over the last few decades due to increased societal pressure and changing fashion trends . over the years
, the colouring agents have diversified in nature with the arrival of oxidative hair dyes that include many synthetic and natural agents .
the more commonly used hair dye agents include resorcinol , henna , hydroquinone , lead acetate , m - aminophenol , n - phenyl - p - phenylenediamine , o - aminophenol , p - aminophenol , and ppd or related para - amino compounds such as toluene-2,5-diamine sulfate .
nearly 5% of 21,515 individuals were allergic to ppd in a multicentric european study . similarly , ppd was the commonest sensitizer among cosmetics in two separate indian studies .
hairdressers and textile dye workers are particularly at risk and have high prevalence of ppd contact dermatitis varying between of 15% and 45% or as high as 58% because of high occupational exposure . apart from hair colorants
, sensitization may also occur from ppd in textile or fur dyes , black rubber , temporary tattoos , and photocopying and printing inks .
similarly , hair dye dermatitis is observed among urban dwellers more often than in their rural counterparts ; a prevalence of 84% versus 16% among urban versus rural population has been observed in a previous study . this trend may be because of easy availability of hair dyes , increased awareness , and peer pressure to look younger among the urban population .
sensitization from ppd can occur at any age including among children as it depends mainly upon exposure to the allergen .
the weighted average of ppd sensitization in the general population is estimated to be 1.0% .
however , the prevalence of ppd sensitivity varies according to cultural and occupational practices and a higher prevalence is seen in asia ( 2%12% ) , particularly among asian males .
most cases occur in middle - aged individuals between 30 and 50 years of age and males are affected two times more than the females .
this increased prevalence in middle - aged people has been attributed to the frequent use of hair dye in order to camouflage their greying hair .
higher sensitization to hair dye among males is probably due to the more frequent applications that are required for facial ( beard ) hair as compared to scalp hair .
clinically , hair dye dermatitis can present as both irritant dermatitis and allergic contact dermatitis .
it may also cause severe clinical contact reactions ranging from anaphylaxis to oedema of the scalp , face , and eyelids .
scalp and scalp margins , and beard skin are the reported sites that are commonly affected due to hair dye usage , while hands and other body sites may be affected among persons not using gloves while dying hair .
mild to moderate contact reactions such as erythema , oozing , and ulceration typically at the scalp margin , and on the ears and neck are common as a result of direct contact .
ho et al . observed that hair dye dermatitis primarily involved the face and neck ( 28% ) , and hands ( 25% ) , whereas widespread dermatitis occurred in 17% of patients .
airborne contact dermatitis , irritant contact dermatitis , photocontact dermatitis , periorbital eczema , hand eczema , lichenoid lesions , and lichen planus pigmentosus - like pigmentary changes were the commonly observed clinical patterns of hair dye dermatitis , whereas contact leukcoderma , contact urticaria , lymphomatoid papulosis , erythema multiforme - like or prurigo nodularis - like lesions , and anaphylaxis have occurred atypically with ppd .
localized contact dermatitis was observed in nearly all our patients , particularly involving the scalp and/or scalp margin in 49 patients , face , beard , and periorbital skin in 23 , and hands and feet in 12 patients .
uncommon patterns such as airborne contact dermatitis ( 9 patients ) , hand dermatitis ( 5 patients ) , eyelid dermatitis ( 4 patients ) , disseminated dermatitis and erythema multiforme - like lesions ( 1 patient each ) were also observed in this series .
although ppd is not considered photosensitizing , dermatitis localized to photoexposed skin and chronic actinic dermatitis ( actinic reticuloid ) in a few patients suggests its possible photosensitizing potential .
it is also possible that persistence of allergen and photoaggravation of dermatitis is responsible for photolocalization of ppd induced dermatitis in some individuals .
contact sensitivity to fragrance mix , colophony , paraben mix , and thiuram mix , observed in eight patients was perhaps due to prior sensitisation as they are present in most topical medications , cosmetics , perfumes , and pharmaceuticals .
prohaptens and their metabolites in the skin , particularly the p - benzoquinone , are considered responsible for its allergenicity and cross - reactivity .
another postulation is that bandrowski 's base , a trimer of ppd formed on exposure , is perhaps responsible for its allergenicity .
however , patch testing with these agents individually is negative in a sizeable population of patients who had tested positive to for ppd .
a genetic polymorphism in the cutaneous metabolism of ppd too has been suggested to explain why only a few persons using hair dyes develop contact sensitivity or variable allergic responses from to it .
reported a personal history of atopy in 24% of their patients with cosmetic contact sensitivity .
atopic individuals are perhaps at an enhanced risk of for cosmetic contact sensitivity because of increased allergen penetration through impaired skin barrier .
a personal history of atopy was observed in 18 ( 33% ) patients in our study .
the european union cosmetic directive allows a maximum concentration of 6% ppd in hair dyes , while the bureau of indian standards has set a maximum permissible limit of 30% and not less than 3% ppd after dilution of the powder form and a maximum of 4% and not less than 1.2% after dilution of the oxidation liquid type
. however , many manufacturers fail to comply with these standards , and a strict legislation is perhaps needed for adherence to safe limits of ppd in hair dyes .
it is also desirable that manufacturers print directions in bold text over the product package regarding safe use of the hair dye .
there is also an urgent need to increase awareness among consumers regarding the adverse effects of hair dyes , the available safer alternatives , and the significance of performing sensitivity testing prior to actual use , in adherence of usage instructions .
the hair dyes usually have two separate components , the colorant and the developer that are mixed before application .
we did not patch test these agents in our study and that might have been responsible for negative patch test results in 26 of our patients .
unavailability of hair dye allergens other than ppd , the small number of patients , and not testing with patient 's own hair colorant or other cosmetics may have resulted in our missing some cases of compound allergy .
the hair dyes usually have two separate components , the colorant and the developer that are mixed before application .
we did not patch test these agents in our study and that might have been responsible for negative patch test results in 26 of our patients .
unavailability of hair dye allergens other than ppd , the small number of patients , and not testing with patient 's own hair colorant or other cosmetics may have resulted in our missing some cases of compound allergy .
 background : the contact allergic reactions from p - phenylenediamine ( ppd ) in hair dyes vary from mild contact dermatitis to severe life- threatening events ( angioedema , bronchospasm , asthma , renal impairment).objectives : to study the clinical patterns and ppd contact sensitivity in patients with hair - dye dermatitis.materials and methods : eighty ( m : f 47:33 ) consecutive patients aged between 18 and 74 years suspected to have contact allergy from hair dye were studied by patch testing with indian standard series including p - phenylenediamine ( ppd , 1.0% pet).results:54 fifty - four ( m : f 21:33 ) patients showed positive patch tests from ppd . 
 eight of these patients also showed positive patch test reaction from fragrance mix , thiuram mix , paraben mix , or colophony . 
 fifty - seven ( 71% ) patients affected were aged older than 40 years . 
 the duration of dermatitis varied from < 1 month to > 1 year with exacerbation following hair coloring . 
 forty - nine patients had dermatitis of scalp and/or scalp margins and 23 patients had face and neck dermatitis . 
 periorbital dermatitis , chronic actinic dermatitis , and erythema multiforme - like lesions were seen in 4 , 2 , and 1 patients , respectively.conclusions:hair dyes and ppd constitute a significant cause of contact dermatitis . 
 there is an urgent need for creating consumer awareness regarding hair - dyes contact sensitivity and the significance of performing sensitivity testing prior to actual use . 
INTRODUCTION
MATERIALS AND METHODS
RESULTS AND OBSERVATIONS
DISCUSSION
Limitations