Preservatives in Natural Products: Phenoxyethanol

The primary focus of Nature’s Pulchritude is to educate. This post is the fourth in a series of in depth posts that will educate you about the various preservatives in hair and skin products, as well as their potential toxicity.

PURPOSE

Preservatives are added to cosmetics, personal care products, and food to maintain a products integrity and stability by inhibiting or reducing the growth of microorganisms such as bacteria and fungus (FDA).  Most products sold via retail sit for extended periods of time during shipping, in a warehouse, and on store shelfs that allow enough time for a product to spoil or cause microbial growth which render the product unfit for use.  This is particularly true for products that contain water, such as many conditioners and moisturizers, and other active ingredients (antioxidants and emulsifiers) that would otherwise lose their effectiveness and stability over time.

Preservatives are chosen in cosmetics based on a variety of factors which include ability to inhibit growth over a broad spectrum and method of derivation (natural vs. synthetic).  Preservatives tend to be in concentrations less than 2% of the weight of the formula, however, widespread use of potentially harmful preservatives, such as parabens, has been a great cause of concern for some scientists and consumers.  The Food, Drug, and Cosmetic Act does not grant the Food & Drug Administration the authority to regulate the use of preservatives unless it is known to be “poisonous or deleterious” (FDA).

PHENOXYETHANOL

This ingredient first came to my attention as I was researching companies to feature in The Globes. This ingredient was literally used in over 90 percent of the brands I had been researching, whether under ‘phenoxyethanol’ or as Optiphen^TM which is a mixture of phenoxyethanol and Caprylyl Glycol. All of the products I was researching were of course marketed as using natural ingredients, though not certified organic. The first questions I had were “what is it?” and “is it safe?” This ingredient became the inspiration for these series of posts. An ingredient that appears to be so widely used in a niche market should be further investigated.

Chemical Structure of 2-Phenoxyethanol

Phenoxyethanol is a glycol ether made from alkyl ethers of ethylene glycol, though it can be derived from natural sources. Also known as Ethylene glycol monophenyl ether, it is a bactericide (kills bacteria) that is used in cosmetics, pharmaceuticals, and vaccines. Phenoxyethanol (C₈H₁₀O₂) has increased in usage over that past 5 years because it is a much safer alternative to formaldehyde releasing preservatives and does not have the same negative connotation as parabens. However, phenoxyethanol is not without its own concerns. It use is limited to 1% in Japan and the EU, and it is not suggested for use in baby products as per a warning issued by the FDA.

Hazards
Phenoxyethanol was present in 39% of 204 tested cosmetics products (92 shampoos, 61 conditioners, 34 liquid soaps, and 17 wet tissues), making it the second most abundant preservative detected (of 30), behind methylparaben (Yazar et al. 2010).  Though its use is limited in the EU and Japan to 1%, the Food and Drug Administration (FDA) of the US found that phenoxyethanol “can depress the central nervous system” and “may cause vomiting and diarrhea, which can lead to dehydrating in infants” based on research conducted on a nipple cream for nursing mothers in 2008.  This should be of some concern to mothers who are using products containing phenoxyethanol.  Though the primary pathway is via ingestion, it is always best to exercise caution.

On the contrary, the Cosmetic Ingredient Review declared that phenoxyethanol is “practically non-toxic” to humans when administered orally or through the skin (Lee et al. 2007).  Phenoxyethanol maybe more toxic to infants than adults, though this has not be substantiated based on available literature.  Based on a series of patch tests, Lee et al. found that phenoxyethanol, as well as parabens, can cause sensory irritation of the skin, which typically results in “stinging, burning, and itching that occur[s] without visual signs of skin inflammation” (2007).  Phenoxyethanol was also found to induce urticaria and eczema, a rash of red welts accompanied by itching, in patch tests at 1% after 3 individuals experienced skin irritation after using a product with the preservative (Bohn and Bircher 2008).  However, these reactions (hypersensitivity) from cosmetics is considered very rare.  Phenoxyethanol in the presence of other preservatives can increase risk of allergic reaction (Lee et al. 2007).

CONCLUSIONS

Phenoxyethanol is considered safer than many available preservatives.  It is not known to be toxic in humans, though it can be a skin irritant in some individuals.  This ingredient was previously allowed in products certified organic in the UK by ECOCERT, however, this is no longer a common practice.  While this product itself is not natural, it does serve its purpose as a preservative.  As with the other preservatives covered, it is not without its flaws, however, it appears much safer than other preservatives and is not suspected to be carcinogenic in humans.  Consumers with children should be the most cautious of this ingredient and should do their best to ensure that their child does not consume a product containing this ingredient and limit exposure overall.

References:

Bohn, S. and A. Bircher.  2008.  “Phenoxyethanol-induced urticaria.”  European Journal of Allergy and Clinincal Immunology.  56(9): 922-923.

Lee, E., An, S., Choi, D.,  Moon, S., and I. Chang.  2007.  “Comparison of objective and sensory skin irritations of several cosmetic preservatives.”  Contact Dermatitis.  56: 131-136.

Yazar, K., Johnsson, S., Lind, M., Boman, A., and C. Liden.   2010. “Preservatives and fragrance in selected consumer-available cosmetics and detergents.”  Contact Dermatitis.  64: 265-272.