Positive rates to propyl gallate on patch testing: a change in trend

Abstract

Propyl gallate (E310) has, until recently, been used as a major antioxidant in fatty food and, in the cosmetic industry, in the manufacture of lipsticks. Propyl gallate has a high sensitizing potential; however, the frequency of allergic contact dermatitis from antioxidants of the gallate type was previously thought to be surprisingly low. Previous exposure and orally induced tolerance, as suggested by Khan and colleagues, may have explained the low rates of allergic contact dermatitis to propyl gallate in the past. The objectives were to assess the prevalence of allergic contact dermatitis to propyl gallate in our centre from 1988 to 2005. From 1988 to 2005, 9529 patients were patch tested to the face series, 6973 were females and 2556 were males. Patch tests were read at 2 D and 4 D. Positive reactions were scored as per International Contact Dermatitis Research Group recommendations as negative, +, ++, and +++ reactions. Propyl gallate was used at a 1% petrolatum (pet.). A total of 55 patients had positive reactions to propyl gallate 1% pet. (0.57%), 46 were female (0.65%) and 9 were male (0.33%). Using chi-square, there was a significant difference (P < 0.05) in the positivity rates between the 1988-96 period (0.45%) and the 1997-2005 period (0.77%). A review of our face series performed in the last 18 years has shown a statistically significant increase in propyl gallate-positive rates on patch testing over the last decade. An increase in its use in the cosmetic industry may well be the explanation for this. Nevertheless, a concomitant reduction of propyl gallate as an antioxidant in food, with oral tolerance being less likely to develop, may also be a contributing factor in the increasing trend of allergic contact dermatitis caused by propyl gallate.

Cosmetic Contact Allergens

“…Although the number of contact-allergic reactions to propyl gallate (and other gallates, also used as food additives) was reported to have increased over the years [29], which was attributed to an increased use in cosmetics concomitant to a reduced use in food (with oral tolerance reactions less likely to develop), we only observed few reactions to it. Sulfites and bisulfites often cause contact allergy and have shown to be relevant allergens in topical pharmaceutical products, but also in cosmetic creams and hair dyes [30].…”

Cosmetic Contact Sensitivity in Patients with Melasma: Results of a Pilot Study

“…Dodecyl gallate, octyl gallate, and propyl gallate (gallate mix) are antioxidant substances used as preservatives in cosmetics (lipstick, liposome containing creams, body lotions, facial moisturizers, facial cleanser, body wash and cleansers, hair conditioners, and foundation lotions), foods, and the topical pharmaceutical preparations. The use of liposome containing creams has been implicated for rise in propyl gallate allergy observed in patients patch tested from 1988 to 2005 over the previous decade [17, 18]. Gallate mix was the second most frequent allergen eliciting positive results in 31% of our patients who have been using various facial cosmetics/skin care products (Figure 4).…”

Scientific Opinion on the re‐evaluation of propyl gallate (E 310) as a food additive

“…Propyl gallate has a high sensitising potential and cases of allergic contact dermatitis to propyl gallate have been reported (Kraus et al, 1990;Garcia-Melgares et al, 2007;Perez et al, 2008). They are usually cheilitis and dermatitis of the hands.…”