Many preservatives that have been used safely for decades, with years of safety data supporting their use, are all of a sudden coming under scrutiny due to a few published reports, not all based on real science, but rather a perspective or agenda. They are being blamed for being irritating, cancer-causing, bad for the environment or just for being of synthetic origin! Meanwhile, newer or alternative preservatives, with not nearly as much supporting safety data, are being explored by consumers embracing natural and organic trends and companies looking to capitalize on consumers’ innate chemophobia.
In most products, preservatives represent a very small percentage of the overall formulation – typically less than one percent of the total formula. They are usually listed among the last few ingredients in the ingredient declarations, which tells us that they are generally effective and used at very small levels. Being that they perform one of the most important functions in cosmetics preparations – making the product safe for use – consumer attention on the negative aspects of preservatives in products clearly shows the disconnect between what manufacturers know and what consumers know. The responsibility to set the record straight often lies on the shoulders of skin care therapists and aestheticians.

Why do we need preservatives legally?
According to the Food, Drug & Cosmetic Act of 1938, it is illegal for cosmetic companies to sell adulterated products. Adulteration refers to several things, among them to produce contamination by foreign substances such as microbes that are not supposed to be in the ingredient or product.
Antimicrobial preservatives prevent or inhibit microbial growth, preventing adulteration of the product. Dozens of different microbes can grow in cosmetics; among the most common are families of mold, fungus, yeast, virus, and bacteria. There is not a single ingredient in our industry that can successfully control every type of microorganism capable of surviving and multiplying in skin care products. That is why synergistic combinations of ingredients, preservative blends or “concerts” of preservatives, are normally used to address the array of microbes that can grow in a skin care product containing water or water-soluble ingredients.
Any product manufactured without a preservative to prevent and control microbial growth will start to grow organisms, some of which may be potentially dangerous. That is why the Food and Drug Administration (FDA) requires that manufacturers provide proof that each batch produced is adequately preserved. Manufacturers are required to perform microbial-challenge testing and demonstrate that the product is not contaminated with microorganisms, which may be pathogenic and have a low density of non-pathogenic microorganisms.
Microbial contamination can also lead to product instability such as product separation, discoloration, and formation of gases and odors. Preservative systems that include ingredients other than antimicrobials are used to ensure product stability and shelf life. They include antioxidants that prevent rancidity of oils, proteins, fats, and lipids, humectants that prevent water evaporation, pH adjustors that prevent pH fluctuations, chelators that control mineral contamination, emulsifiers that prevent emulsion separation and ultraviolet-screens for color, fragrance stability, and protection of antioxidants in the formulas.
In susceptible people, there is a downside to some preservatives, because they can cause allergies, dermatitis, and other side effects. This is because, by their nature, preservatives are biologically active, since their job is to kill microorganisms. Even though they are very specific in that activity, they have the capacity to harm other living cells. Most of us can handle this risk without any side effects, while some clients with low tolerance can experience skin irritation and sensitization from some types of preservatives. The type of preservative used, its concentration, and the type of product in which it is used, will greatly increase or decrease a preservative’s irritation potential.

Preservative-Free Products
While a very small number of products can be truly “self-preserving” or offer minimal potential contamination, most can be extremely difficult to formulate, have many additional stability problems, and cause irritation.
Products that may provide the best opportunity for the lowest amount of preservation or no preservation include anhydrous products, where the lack of water may preclude the growth of water-borne bacteria (such as dry powders, silicone and oil-based products), as well as acid-based formulas with a very low pH. Most microbes find this environment inhospitable.
Most cosmetic chemists agree that a truly preservative-free product would have to be treated like fresh food. It would have a very short shelf life and the product would need to be refrigerated, which would be very costly and inconvenient for consumers. Even then, a preservative-free product would pose a tremendous risk for the health and safety of the consumer. So is the risk really worth the benefit?

Paraben Controversy
We could not possibly discuss preservatives without mentioning the paraben controversy. One article, “Concentrations of Parabens in Human Breast Tumors,” proliferated about the dangers of parabens.1 The scientific community immediately refuted the claims made by Dabre, pointing out the poor use of science in the methodology and conclusions. Despite overwhelming evidence compounded over the last decade that parabens do not have the negative effects initially presumed, many of our clients still consider product with parabens as harmful. However, at this time, despite many false reports in our industry, no regulatory authority has made any attempt to limit the use of parabens in cosmetics or foods or any other industry utilizing parabens, due to their benefits and lack of adverse findings.2
This may come as a huge surprise to many in the professional skin care industry, but according to reliable industry sources, about 75 to 90 percent of personal care products on the market still contain parabens, including some of the best-selling products sold by mass market retailers and big department stores. While most of these products still utilize parabens as their main preservative system, some may contain an ingredient that is preserved in parabens prior to being added to the formula, without parabens actually being listed on the ingredient label. Either way, having parabens in the vast majority of skin care formulations does not seem to affect sales in the mass market, according to a study published by Datamonitor. This study indicates that only about one-third of consumers in the United States were concerned about parabens in their cosmetic products.3

Selecting the Preservative
There are many factors involved in the selection of the type and concentration of preservatives in a formula and far too often in today’s climate, formulators find themselves handcuffed by the consumer and marketing notions when making this selection. When choosing a preservative system, the chemist has to focus on actual product characteristics and usage such as a physical form of the product, the pH, and the end usage of the product, including the area of the body where the product will be used. Regulatory restrictions differ from region to region in the world and regulatory bodies in different countries allow different ingredients to be used for preservation.

Science, Not Fear, Needs To Lead the Way
Unfortunately, the perception of certain ingredients used in our industry for product preservation has become more important than the actual science. These very useful and much-needed ingredients are sometimes avoided simply because people believe that consumers overwhelmingly want to avoid them. The most important strategy regarding preservatives is finding the right balance with enough preservatives necessary to control microbial growth, but not so much as to cause reactions or side effects. The key is allowing science to take the lead in finding innovative preservative solutions and not allowing misinformed marketing decisions to dictate the safety of your customers.

References:
1 Dabre PD., (2004). Concentrations of Parabens in Human Breast Tumors, Dabre PD. Et al, Journal of Applied Toxicology, Vol. 24, 5-13.
2 Steinberg, David C., (2012). Preservatives for Cosmetics, Third Edition. Australian SCC.
Williams, Ric, Sellars, Rita. (2010). Preservatives Used in Personal Care Products. Personal care Truth or Scare.
3 Romanowski, Perry. (2014). Consumers Think About Parabens
in Cosmetics?
4 Cotte, Bristin Fraser. (2011). Why Do Emulsions Need Preservatives?

Director of Product Development for YG Laboratories, Irena James has educated generations of students and industry peers on skin care ingredients, treatment protocols, and brand development. James’ versatile experience in the skin care industry spans over 20 years, during which she worked as an aesthetician, educator, territory sales manager, and director of business development in the EU. She is an assistant instructor at the UCLA Extension Cosmetic Sciences Program and a member of BIW and the Society of Cosmetic Chemists.