The paraben debate: Should you be worried about a paraben allergy?
A recent report determined the safety of parabens as preservatives in cosmetics, food, and pharmaceuticals, and evaluated if a paraben allergy is a problematic health concern.
Looking for “paraben free” on labels of various products has become a new trend. The product reviewers, health enthusiasts, and some self-proclaimed experts have been advocating the use of products without parabens.
While some members of the paraben family may be truly infamous for causing damaging effects, generalizing the claim that all parabens are responsible for every misfortune from breast cancer to birth defects, from skin reactions to damaging hair is misinformation that has led to apprehensions about and fear of parabens as preservatives.
So, how much of it is true? Are parabens really bad for you? Is paraben allergy something you should be worried about?
Parabens are ubiquitous as preservatives
Parabens are a family of esters of parahydroxybenzoic acid. Since the time they were first reported in 1924, their use as antimicrobial preservatives has steadily increased in cosmetics, food stuffs, and pharmaceuticals. There are several important reasons why parabens were accepted worldwide as preservatives. They have minimal toxicity, low cost, and are not chemically reactive. They are also the preservative of choice because parabens have high stability, no odor or taste, and do not discolor or harden with time.
The need for antimicrobial preservatives
The cosmetic products, pharmaceuticals and certain types of foods, if left without preservatives will quickly become contaminated with bacteria, mold, and fungi. The contamination not only spoils the product; it can also result in infection if the contaminated product is used. Parabens are an easy choice as antibacterial and antifungal agents leading to their extensive use as preservatives.
The paraben mix is the most effective antimicrobial
The paraben types that are most widely used include methylparaben, ethylparaben, propylparaben, and butylparaben. The antimicrobial activity of each paraben is significantly different from each other. Usually, different combinations of parabens at varying concentrations, known as the paraben mix, are used to achieve the desired shelf life of a product.
Methylparaben and ethylparaben are the two most commonly paired parabens. To increase the antimicrobial activity of a product against a variety of bacteria, sometimes a second non-paraben preservative is added that allows the addition of all preservatives-both paraben and non-paraben, in very low concentrations, thus making them safer to use.
Paraben allergy is rare
Paraben allergy, although not uncommon, is considered rare in relation to the widespread use of parabens. In people with normal skin, parabens are usually non-irritating and non-sensitizing. However, in a small percentage of people, parabens may cause allergies or contact dermatitis. The North American Contact Dermatitis Group found only 2.3% of their patients to have a positive allergy test to parabens.
Scientists have conducted several studies to understand the chemical nature, metabolism, and toxicity of parabens in relation to paraben allergy. Interestingly, the researchers have closely monitored paraben allergy for decades and have found that the frequency of sensitivity to parabens has remained low and stable despite a steady increase in the use of parabens as preservatives.
A new report recently published by the American Contact Dermatitis Society reviews the well-established safety of parabens as allergens. The researchers used the databases of the Contact allergy management program (CAMP), the Environment Working Group (EWG), and SkinSAFE to assess the causal relationship between parabens and allergic reactions.
Sensitization potential of parabens
The sensitizing potential is the ability of parabens to penetrate through the skin and cause a reaction. Paraben allergy has been extensively studied and results have found parabens to be safe. Most studies report low sensitization rates of parabens ranging from 0 to 10.9%. Parabens used in cosmetics showed no or very low potency to irritate the skin. Therefore, in comparison to other alternatives, parabens remain one of the least allergenic preservatives.
Exposure to parabens through cosmetics, medications, and foods
In cosmetic preparations, very low concentration of 0.1%-0.8% of parabens is used. Given the poor absorption through the skin, parabens applied to skin contribute to a very low systemic exposure compared with exposure from medications and food. Studies have shown that paraben exposure from cosmetics rarely causes allergy. Studies found parabens as the causative agent in only 1% of all cosmetic allergy patients.
The methyl and propyl parabens are the most commonly used parabens for preserving food. The FDA approves the use of these parabens with limits of 0.1% each. The use of propylparaben, however, has shown some adverse effects in the reproductive tissues of rats in some studies. Therefore, propylparaben as a preservative in foods has been removed in Europe.
In pharmaceuticals, paraben concentrations rarely exceed 0.1% based on current guidelines and recommendations. Certain products such as oral solutions and syrups are still safely using concentrations of 5% to 20%.
The paraben paradox
There are several issues regarding paraben allergy and usage that are commonly known as the paraben paradox. The paradox is usually seen in individuals who have dermatitis and show a positive paraben allergy test while they can use paraben-containing cosmetics on other intact, uninvolved areas of their body without any reaction. This may be the result of sensitization by the topical medication that usually has a higher concentration of parabens than the cosmetic products or this may be the result of the use of medication on diseased skin that allows easier penetration of paraben as an allergen compared with intact skin.
In agreement with the paradox, most cases of paraben allergy only develop when paraben-containing products are applied to damaged skin with a compromised barrier function as seen in cases of leg ulcers and skin dermatitis.
The cloud of suspicion over the use of paraben
Numerous studies have been conducted to evaluate the link between parabens and allergic reactions. The North American Contact Dermatitis Group in the US and Canada, the European Environmental and Contact Dermatitis Group, as well as other international agencies have demonstrated that parabens have withstood four decades of extensive skin testing.
The issue of paraben allergy was a health concern back in the 20th century. But the recent reports suggest that parabens are one of the least allergenic preservatives available today. For this reason, in this report researchers have designated parabens as the nonallergen of the year.
There are other concerns that still inflame the controversy around the use of parabens. Some of these concerns include endocrine disruption, carcinogenicity, exposure risk in neonates and small children, reproductive and emotional disorders, and environmental impact. The causal link between parabens and most of these issues have not been conclusively proven. However, FDA and most other regulatory authorities have found parabens to be safe as preservatives from an allergy standpoint.
The paraben debate will most likely continue
Several industry leaders, researchers and regulatory authorities have worked for years to address the issue of paraben allergy. Contrary to public perception and concern about paraben reactions, the authors of this report selected paraben mix as the nonallergen of the year. While paraben allergy is not a problematic issue and this report concluded paraben as the nonallergen of the year, the research on the effects of parabens on human health continues and so does the debate whether to use paraben-containing products or go “paraben free”.
Written by Preeti Paul, MS Biochemistry
Reference: Anthony F. Fransway et al., Parabens: Contact (Non) Allergen of the Year. American Contact Dermatitis Society (2018). DOI: 10.1097/DER.0000000000000429
