Wood tars allergy, cross‐sensitization and coal tar

Abstract

In a population of 1883 patients tested for allergic contact dermatitis (1985-1988), a prevalence of 5.4% (103 cases) was seen for wood tars (ICDRG allergen, 12% pet.) sensitization. In this group (n = 103), retrospectively, a combined allergy was seen to wood tars and fragrance mix in 43% and to wood tars and balsam of Peru in 31%. A combined allergy to wood tars and coal tar was seen in 19 patients (18.5%): 14 to liquor carbonis detergens (LCD), 8 to lianthral and 3 to both LCD and lianthral. Within the group with wood tars allergy (n = 103), a minority (n = 37) had a history of atopic dermatitis. Comparison of the test results in atopic and non-atopic subgroups (within the group of 103) revealed a higher incidence of combined wood tars-fragrance mix allergy in the atopic group (n = 37). In this group, a lower incidence of combined wood tars-coal tar sensitization was seen in comparison with the non-atopic group (n = 66). The authors believe that combined "wood tars-coal tar" allergy could be the consequence of cross-sensitization rather than due to long-term previous topical treatment with tar derivatives. The high % of cross-allergy between wood tars and fragrance mix emphasizes the role of wood tars as an important indicator allergen in perfume allergy.

Contact sensitivity in patients with venous leg ulcer: A multi‐centric Indian study

“…Wood tar mix was 1 of the most frequent (20%) allergens also found in the study by Saap et al In their study, sensitivity to balsum of Peru and bacitracin were the most frequent. Wood tar sensitisation was also 1 of the common sensitisers in a large study involving 1883 patients with allergic contact dermatitis . Wood tar is used in the flavouring of certain food.…”

“…Wood tar sensitisation was also 1 of the common sensitisers in a large study involving 1883 patients with allergic contact dermatitis. 20 Wood tar is used in the flavouring of certain food. A high degree of cross-allergy between wood tars and fragrance mix can occur.…”

Contact Sensitivity in Patients With Leg Ulcerations

“…We also found a high cross-reactivity between patients sensitized to balsam of Peru and wood tar mix, which has been shown in prior investigations. 19 In our study population, we were not able to find a correlation between ulcer duration and number of allergen sensitivities, as had been shown in a prior study. 4 However, ulcer duration was determined through a patient questionnaire, which may have introduced recall bias.…”

Topical tar: Back to the future

“…In those patients who had a combined allergy to wood and coal tar, cross-sensitization was deemed the reason as opposed to prior treatment with tar compounds. 46 In another report, a patient had been exposed to topical pine tar only; however, she also showed a positive reaction to coal tar, birch tar, beech tar, and juniper tar, supporting the finding that these reactions are a consequence of cross-sensitization and not prior exposure. 47 …”