Better Left Aloe? Contact Allergens in Aloe Vera Gels.

Abstract

To the Editor: Gel from the aloe vera plant is popular for its soothing and hydrating properties. Aloe vera gel is rarely allergenic; however, aloe vera products sold in stores may contain additional allergenic ingredients. In our experience at a patch test clinic, we have anecdotally observed that many commercial aloe vera gels contain formaldehyde releasers (FRs). The aim of the study is to assess the presence of common allergens, especially FRs, in aloe vera gels. We reviewed ingredients of aloe vera gels sold at Target, Walmart, CVS, Walgreens, and Amazon. Up to 20 gels per retailer were included in the study. Common allergens relevant to personal care products were identified using the North American Contact Dermatitis Group's 2017–2018 significance-prevalence index numbers (methylisothiazolinone, methylchloroisothiazolinone/methylisothiazolinone, fragrance, formaldehyde, propylene glycol, and lanolin).1 Cross-reactors/synonyms were combined into allergen categories; if multiple ingredients were represented by a single allergen category, it was counted only once. Table 1 demonstrates the identified allergens in the 36 included aloe vera gels. The most common allergen category was fragrance (38.9%, 14/36), followed by FRs and propylene glycol (each 27.8%, 10/36). Methylchloroisothiazolinone/methylisothiazolinone was only declared in one gel (2.8%, 1/36), and lanolin was not declared in any of the gels. TABLE 1 - Aloe Vera Gels and Identified Allergens Product Name Fragrance/Botanical Extracts FRs (Listed Ingredient[s]) Propylene Glycol MI/MCI ALODERMA Organic Pure Aloe Vera Gel X AROMATICA Organic Aloe Vera Gel X ATOPALM Kids Cica Aloe Soothing Gel X Absolutely Natural Pure Aloe Recovery Gel Badger Aloe Vera After Sun Gel Bighture Organic Aloe Vera Gel Botanic Hearth Aloe Vera Moisturizing Gel Calypso Aftersun Aloe Vera Gel X X Esfolio Aloe Vera Moisture Soothing Gel Mist X X Forever Living Forever Aloe Vera Gelly X (diazolidinyl urea) Honeyskin Aloe Vera Gel X Lily of The Desert Aloe Vera Gelly Majestic Pure Cosmeceuticals Aloe Vera Gel Mill Creek Botanicals Aloe Vera Gel X NaturSense Organic Aloe Vera Gel Honeydew Hydrating Aloe Vera Gel Unscented Panama Jack Green Ice 8 Ounce Pure Aloe Vera Gel X X (diazolidinyl urea + DMDM hydantoin) X Premium Nature Aloe Vera Gel X (diazolidinyl urea) Sunburnt Ultra Hydrating Aloe Vera Gel Yeteson Aloe Vera Gel Alba Botanica After Sun Aloe Vera Gel X Banana Boat Aloe Vera Gel X CVS Health Aftersun Aloe Vera Cooling Gel X Equate After Sun Soothing Gel With Aloe X X (diazolidinyl urea) X Equate After Sun Sunburn Relief Gel With Aloe X X (diazolidinyl urea) X Fruit of the Earth—Aloe Vera 100% Gel Crystal Clear X (diazolidinyl urea + DMDM hydantoin) Fruit of the Earth Aloe Vera Moisturizing Gel, Unscented X (diazolidinyl urea + DMDM hydantoin) Pura d'or Healing Organic Aloe Vera Gel—Lavender X Sun Bum Cool Down Gel up&up Clear Aloe Vera Gel up&up Green Aloe Vera Gel X X (diazolidinyl urea) X Walgreens—After Sun Gel X (diazolidinyl urea + DMDM hydantoin) Walgreens—Aloe Vera Gel Green X Walgreens—Aloe Vera Gel Lidocaine X X (diazolidinyl urea) X Walgreens—Aloe Vera Gel Sensitive Walgreens Dye-Free After Sun Gel X Total 14 10 10 1 MI/MCI indicates methylchloroisothiazolinone/methylisothiazolinone. Overall, FRs were fairly common in commercially available vera gels. By comparison, a current search of the American Contact Dermatitis Society's Contact Allergy Management Program database showed that only 8.2% (81/989) of moisturizers contain FRs. Other studies of personal care products identified FRs in 9.2% of men's facial moisturizers2 and 3% of baby products.3 Formaldehyde releasers are used as preservatives in personal care products for their bactericidal and fungicidal properties. Allergic contact dermatitis to formaldehyde is well recognized. Although there is a downward trend in the proportion of patch test positivity to formaldehyde and its releasers,4 the North American Contact Dermatitis Group reported a 7.4% prevalence of positive patch test reactions in the 2017–2018 cycle, making it the fifth most frequent allergen.1 Because of increasing concerns of its carcinogenicity, regulations on formaldehyde in personal care products have heightened. In 2020, California became the first state to ban formaldehyde in personal care products and cosmetics, although the law does take effect until 2025.5 If this becomes a trend, there could be a shift in product formulations across the United States. As of today, FRs can still be found in many personal care products, including aloe vera gels. The high percentage of aloe vera gels containing FRs may be attributed to the low shelf life of pure aloe vera gel. In addition to FRs, many aloe vera gels contain other common allergens as well. Providers and patients should be aware that aloe vera gels may be a source of allergic contact dermatitis. Michelle Xiong, BS Department of Dermatology Park Nicollet Health Services Minneapolis, MN Warren Alpert Medical School of Brown University Providence, RI [email protected]Samuel F. Ekstein, BS Department of Dermatology Park Nicollet Health Services Minneapolis, MN Mayo Clinic Alix School of Medicine Rochester, MNAnne B. Neeley, MD Department of Dermatology Park Nicollet Health Services Minneapolis, MN