Changing trends of contact allergens in Thailand: A 12‐year retrospective study

Abstract

Background: Contact allergen prevalences often change. Continual surveillance is necessary to detect trends in sensitization rates and emerging allergens.Objective: To identify the prevalence of, and trends in, the positive reactions to each allergen in the baseline series during a 12-year period in Thailand. Methods: The medical records of 2803 patients who underwent patch testing at the Contact Dermatitis Clinic, Siriraj Hospital, between 2006 and 2018, were retrospectively reviewed. The baseline series used by the clinic was adapted from the European and the International baseline series. The patch testing results were subdivided into 2-year blocks in order to compare the prevalences of each allergen. Results: The prevalences of positive reactions to nickel, fragrance mixes I and II, dichromate, cobalt, carba mix, methyldibromo glutaronitrile, paraben mix, neomycin sulfate, methylisothiazolinone (MI), epoxy resin, N-isopropyl-N-phenyl-4-phenylenediamine and the corticosteroids significantly decreased. Methylchloroisothiazolinone (MCI)/MI was the only allergen associated with a significant increase of positive reactions, from 2.4% to 10.7%. However, the proportion of positive reactions to MCI/MI decreased in the final 2-year period. Conclusions: Approximately half of the substances in the screening patch test series showed a decline in the number of positive reactions, whereas MCI/MI showed an increasing prevalence. Atopic family history, n (%) 985 (35.1) History of metal allergy, n (%) 1087 (38.8) History of cosmetic allergy, n (%) 397 (14.2) History of drug allergy, n (%) 488 (17.4) Positive for at least one allergen, n (%) 1850 (66.0) Of these: clinical relevance, n (%) 1226 (66.3) SUKAKUL ET AL. 125

Methylchloroisothiazolinone/methylisothiazolinone and methylisothiazolinone contact allergy: A 24‐year, single‐center, retrospective cohort study from Turkey

“…Presenting the largest dataset on patch test results with MCI/MI and MI from Turkey, this study highlights some similarities and differences from previous reports on this topic. First of all, many studies on MCI/ MI sensitization reported a clear female preponderance 10,12,16,26,[35][36][37] and a high percentage of patients aged over 40 years. 26,35,38 The present study, however, shows an almost equal sensitization share in male patients.…”

“…21 Consequently, the use of MCI/MI and MI in leave-on cosmetics was prohibited in Europe in 2016 and 2017, respectively, 22,23 and in 2018 the concentration of MI in rinse-off cosmetics was reduced by the European Commission to the same level as MCI/MI, ie, 15 ppm. 24 The introduction of similar legislative measures around the world led to an observable decrease in the incidence of non-occupational ACD due to isothiazolinones, mainly from cosmetic products, 12,16,25,26 while an increase in occupational ACD was observed in some countries after the epidemic due to the lack of legal restrictions of the use of isothiazolinones in industrial products. 26 There are only limited data on ACD from MCI/MI and MI in Turkey, 27,28 where MCI/MI and MI up to 15 ppm and 100 ppm, respectively, are currently allowed only in rinse-off cosmetics.…”

Contact allergy to hair cosmetic allergens in Thailand

“…Hair dyes have been reported to be important contact allergens, some of which are categorized as strong sensitizers . Sensitization to hair dyes, namely p ‐phenylenediamine (PPD), remains an important cause of allergic contact dermatitis (ACD) in many countries . Market surveys of hair coloring products suggest that the constituents used vary according to geographic region .…”

“…4,5 Sensitization to hair dyes, namely p-phenylenediamine (PPD), remains an important cause of allergic contact dermatitis (ACD) in many countries. 6,7 Market surveys of hair coloring products suggest that the constituents used vary according to geographic region. [8][9][10] For example, the primary intermediate PPD is more commonly used in Thailand 8 and the United States, 10 whereas toluene-2,5-diamine (sulfate) (TDA) is more popular in Europe.…”

Contact Allergy—Emerging Allergens and Public Health Impact

“…In Istanbul/Turkey, the prevalence of MI sensitisation also decreased from 9.4% in 2016 to 5.6% in 2018 [102]. In Thailand, an epidemic of MI sensitisation was also observed [103]. Although Thailand followed the EU regulation of cosmetic MI exposure, a market survey indicated the prolonged presence of MCI/MI and MI preserved products, respectively, even after regulation [104].…”