Preservatives in skin care
Preservatives are chemicals that kill bacteria, fungi and molds. They are commonly present in ANY product that contains water. For this reason, oil-based skin care products and anhydrous (water free) skin care products, do not need preservatives. However, creams, lotions and any other product where water is present, require adding a preservative.
If you do NOT use a preservative, or if you decide to believe the hype and try out a "natural" preservative (such as grapefruit seed extracts), then you are putting yourself, and your skin, at RISK. The only way you can avoid using preservatives is if you make your products FRESH every 3 days, and store them in the refrigerator.
We have now started carrying two preservative systems. None are formaldehyde releasing, but they do contain other chemicals that have been getting an (unjustified) bad name (phenoxyethanol and the paraben family).
Parabens and Phenoxyethanol Safety
Parabens have a bad reputation, mainly due to a 2004 study, which basically claimed that parabens in underarm deoderants casued cancer. However, researchers at the National Cancer Institute (NCI), a part of the National Institutes of Health, are not aware of any conclusive evidence linking the use of underarm antiperspirants or deodorants and the subsequent development of breast cancer, The EU Scientific Committee on Consumer Safety, and The U.S. Food and Drug Administration (FDA),do not have any evidence or research data that ingredients (including parabens) in underarm antiperspirants or deodorants cause cancer. Phenoxyethanol is safe and effective at the designated levels in personal care products and cosmetics. It has a long history of effective preservation of these products, and its safety has been extensively documented on human health. Based on available data, the CIR Expert Panel has concluded that ethylhexylglycerin,is safe for use in cosmetical products. The alkyl glyceryl ethers, including ethylhexylglycerin, may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Regulation of the European Union.
Shelf life of products WITH preservatives:
The reason why we suggest 1 month for products with a preservatives is because:
- with preservative = one month
- without preservative = 3 days and must be stored in a fridge.
- ALL preservative manufacturers recommend that proper stress tests and plate counts are done under various temperatures and storage conditions, in order to calculate the correct amount of preservative used in a product in relation to the ingredients used.
- This can take as long as 2 years.
- Note that if you are planning on selling your products (on ebay etc.) then it is essential (to legally protect YOU) that this process is followed, preferably by a qualified person in a registered lab. However, for DIY use, making a product (with preservative) fresh every month is perfectly safe.
The Efficacy and Safety of Natural Preservatives are Questionable
The use of preservatives is essential in most products to prevent product damage caused by microorganisms and to protect the product from inadvertent contamination by the consumer during use. An ingredient that protects the product from the growth of microorganisms is called an antimicrobial. A preservative may also be added to a product to protect it against damage and degradation caused by exposure to oxygen, and in this instance, these ingredients are also called antioxidants. Without preservatives, cosmetic products, just like food, can become contaminated, leading to product spoilage and possibly irritation or infections. Microbial contamination of products, especially those used around the eyes and on the skin, can cause significant problems. Preservatives help prevent such problems.  Whenever a product contains water or might be exposed to water, a preservative has to be added. 
According to the United States Food and Drug Administration Center for Food Safety and Applied Nutrition's Cosmetic Handbook, "The hazard of inadequately preserved cosmetics to human health has been amply demonstrated".  Most cosmetic products contain enough water and nutrients for microorganisms to grow in them quite well. Some of the potential contaminants do no more than make the product unappealing for a consumer to use; they make it smell bad or appear as fuzzy colonies on the surface. Others, such as Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogen, Candida albicans, etc may be pathogenic, requiring medical attention [Table 1.]. Incidences have been reported of blindness caused by contaminated mascara. Skin infections can result from contaminated body lotions, particularly if they are applied to dry, cracked, or otherwise compromised skin. [4-5]
Cosmetics are often stored in the bathroom, where the environment is warm and moist; microorganisms thrive in this environment. Human skin carries a bioburden, and tap water is not sterile. Both of these elements are routinely introduced into cosmetics. Consumers add water to shampoo so as to squeeze the last bit out of the bottle, then place the remnants back on the shelf to use the next time. Young girls routinely share makeup products. Skin care products often come in large, wide-mouth containers that the entire family can use. Even the most meticulously prepared product can become contaminated under these circumstances. Cosmetic manufacturers must take all of this information into consideration when choosing a preservative system for their products. 
The use of a conventional chemical preservative along with some innate capacity of the formulation to resist spoilage [due to the high level of solvents and low water content], was previously sufficient to protect the product during manufacturing and throughout its lifetime of use by the consumer. However, modern product formulations with eco-compliant ingredients are under increased pressure by ecolabeling organizations to abandon the use of conventional chemical preservatives in favor of alternative substances that are seen by various groups to be more “natural”. [6-7] Concurrently, consumers and environmental groups are demanding that products be more “environmentally-preferable” in addition to maintaining the same standard of effectiveness at the lowest possible price. With relevant changes such as reduced volatile organic content [VOC], elimination of heavy metals and replacement of solvents with water, products may be perceived as more “green”, but the very real consequence of increased microbial susceptibility must be acknowledged. The removal of ingredients, which once created an inhospitable environment for bacteria and fungi, has a significant impact on product quality. Ineffective preservation of these products and the raw materials used to produce them can have detrimental results including significant changes in viscosity, pH drift, color change and foul odor, all of which can occur while destroying the performance of the product. 
Preservatives are often referred to as biocides, and biocides are by definition toxic and usually lethal to bacteria and fungi. A successful preservative must be broadly effective against a variety of bacterial and fungal [including molds and yeasts] species, or alternatively a combination of an effective bactericide and an effective fungicide may be used. A natural non-toxic alternative, that is still effective in controlling a broad spectrum of microorganisms, may at best be deemed an unrealistic expectation.  Beyond preserving consumer and industrial products, biocides must be compatible with other ingredients in the formulations. Fortunately, conventional preservatives are usually added at less than 0.1% active ingredient, and compatibility issues are infrequent. In contrast, non-traditional [natural alternative] preservatives are typically used at concentrations greater than 1% to achieve antimicrobial efficacy and they may significantly alter other properties of formulations. To achieve potentially the same level of efficacy, organic acids and essential oils are generally required at concentrations of 20 to 50 times and 20 to 200 times greater than the conventional preservatives, respectively.  To obtain a registration for a preservative, the preservative supplier must generate an extensive data package including toxicology, environmental fate, exposure, product chemistry, and efficacy studies, which is not always the case with natural preservatives.  All natural products cannot be considered de facto “safe” because some of these materials have been shown to elicit allergic reactions, and infections in humans which may be amplified at the high use levels of 1 to 10% required for sufficient antimicrobial performance. 
The type of preservative formulators use for “natural” cosmetics include some of the following: alcohol, benzoic acid, boraxitrus seed extracts, citric acid, copper salts, essential oils, phenoxyethanol, fragrance oils, glycerin, hinokitiol, honey, japanese honeysuckle extracts, lactic acid, melaleucol [tea tree] oil, perillic acid, potassium sorbate, salicylic acid, vitamin E, salt, silver chloride, sodium gluconate, sodium benzoate, sorbic acid, sugar, usnic acid, wasabi extract, zinc salts. For professional formulas the most common are sodium benzoate, phenoxyethanol, or sorbic acid. However, these don’t work for every application. 
It’s a common myth that anti-oxidants like vitamin A, C, E citric acid, Grapefruit Seed Extract and rosemary extract, essential oils, potassium sorbate and sugar are preservatives BUT THEY ARE NOT! [14-17] Vitamin E is an anti-oxidant that can help retard rancidity, but it is not a preservative that will prevent microbial growth. Citric acid can be used as an anti-oxidant that can help retard rancidity, but it will also mess with the pH of the product, making it more acidic by 1 pH at 0.2% or so.  Grapefruit seed extract [GSE] is derived from the seed and pulp of grapefruits, and it may contain many lovely things - anti-oxidants, flavonoids, Vitamin C, citric acid, phytosterols, and tocopherols, but it is not a preservative. It may behave as an anti-oxidant in some products, but it will not keep the microbes and fungi out of lotions and other formulations. Study after study has shown that the preserving power of GSE comes from the preservatives added to the product. Various studies have shown GSE contains benzethonium chloride, benzalkonium chloride, triclosan, and various parabens, and these are what offer the bacteria, fungus, yeast, and mold fighting powers attributed to GSE. Thus, it is concluded that the potent as well as nearly universal antimicrobial activity being attributed to grapefruit seed extract is merely due to the synthetic preservative agents contained within. Natural products with antimicrobial activity do not appear to be present. [15,17]
Essential oils are not preservatives also. They might have some anti-microbial features [like eugenol], but none of them have been proven to be effective preservatives in cosmetic products.  According to Preservatives for Cosmetics by David C. Steinberg, essential oils that have demonstrated antimicrobial activity include caraway, cinnamon, clove, cumin, eucalyptus, lavender, lemon, rose, sage, sandalwood and thyme. Unfortunately, the percentage required to adequately protect a product from microbial growth generally exceeds the recommendations for safe amounts of essential oils to use in skin care products. Rosemary Oil Extract is an antioxidant, meaning that it will remove free radicals from a blend whether it is a lotion, soap, or oil. ROE is wonderful for adding life to oils and preventing them from going rancid, but it is not a preservative in the sense of bacterial inhibition. Bacteria can still grow in products if ROE and water are both present. [2,16]
Sugar cannot be used as a stand-alone preservative in bath and body products. It is true that sugar can be used as a preservative such as with jams and jellies, but it is important to remember that the potency behind its preservative nature in these applications is that in jams and jellies, they are preserved in a vacuum; with no exposure to air.  Potassium sorbate can effectively preserve against mold and yeast, but it is not useful for protecting from bacteria. It is not at all effective in products with a pH over 6, which most lotions are. While potassium sorbate is found in nature, any available today would have been synthetically made so it is not all-natural. It can also cause contact dermatitis. Vitamins A, C can extend the shelf life of products by preventing oxidation and by slowing the growth of certain bacteria, and, they are good for health. But, these vitamins are not effective as broad-spectrum preservatives and cannot replace other preservatives in all products. For example: orange juice is loaded with Vitamin C. But, would anyone want to drink a glass that was left in the bathroom for a couple of months? 
There are a number of types of microbes that can grow in cosmetics and some of them are dangerous. There is the Staphylococcus epidermidis, bacteria that can be found living on color cosmetics like lipsticks, eyeshadows and eyeliners. This bacteria naturally lives on the skin but some strains can cause infection. This is why no one should share color cosmetics with others. Another bacterial group in cosmetics is Staphylococcus Warneri, which is normally found on the skin. If one is sick and has a compromised immune system this bacteria can cause problems. In extreme cases, this bacteria has been associated with heart valve damage. It’s something that should be avoided. Then there are bacterias that can cause pneumonia, lower respiratory infections, urinary tract infections and more. There are also yeasts that can cause thrush, and a variety of molds that can cause allergic reactions, cornea infections, and lung damage. The length of time that someone has to be exposed to a microbe to develop a sickness depends on too many factors to give a simple answer. It could be just a couple of microbes one time and someone gets sick. Or someone could be one of those people who are particularly tolerant of microbes and never gets sick no matter how much exposure he or she has. Since no one can know it’s best to avoid exposure whenever possible. 
Here is just a sampling of what preservatives can protect from. These microbes have been found growing in cosmetics ranging from lotions, shampoo/conditioners to lipsticks etc. 
Bacteria - Gram Negative Non-Fermentors:
- Acinetobacter sp. – Can cause life-threatening infections in compromised individuals.
- Alcaligenes sp. – Opportunistic infections
- Pseudomonas sp. [putida, fluorescens, pausimobilis, aeruginosa, etc] – Second most common infection in hospitals
Bacteria - Gram Negative Fermentors:
- Citrobacter freundii – Can cause life-threatening infections in compromised individuals.
- Enterobacter sp. [ agglomerans, aerogenes, gergoviae] – infections include bacteremia, lower respiratory tract infections, skin infections, soft tissue infections, urinary tract infections, UTI, endocarditis, intraabdominal infections, septic arthritis, osteomyelitis, and ophthalmic infections.
- Klebsiella sp. [oxytoca, pneumonia] – Causes pneumonia.
- Proteus sp. – Causes mastoiditis.
- Serratia sp. [marcescens, odorifera rubidaea] – opportunistic pathogen
Bacteria - Gram Positive:
- Bacillus sp.
- Staphylococcus aureus – Staph. infections
- Staphylococcus epidermidis – Staph infections
- Enterococcus sp. – Urinary tract infections
- Streptococcus sp. – Strep throat. Meningitis
- Propionibacterium sp. – Acne Yeasts:- Candida sp. – Can cause thrush. Systemic infection kills 40 – 50% of people infected.
- Saccharomyces sp. – Food spoilage
- Torula sp., Zygosaccharomyces sp. Molds:
- Absidia sp. – Causes Mucormycosis
- Alternaria sp. – Human allergen
- Aspergillus sp. - Produces aflatoxin which is both a toxin and a carcinogen
- Cladosporium sp. – reported to cause infections of the skin and toenails
- Fusarium sp. – Infections may occur in the nails or the cornea
- Helminthosporium sp.- Asthma and respiratory infections
- Hormodendrum sp. – Allergies
- Geotrichum sp. – Causative agent of geotrichosis
- Phoma sp. – Can cause cutaneous or subcutaneous infections
- Aureobasidium sp. – Can damage lungs
- Rhizopus sp. – Can cause a fatal fungal infection zygomycosis
There have been serious problems from spoiled and contaminated cosmetics which had contained natural preservatives. In a Barcelona hospital, five intensive care patients became infected with a deadly bacteria called Burkholderia cepacia. Officials traced the illness to a moisturizing body milk used in the patients care. The outbreak occurred at the Universitari del
Mar Hospital in Barcelona, where it was common practice to apply moisturizer after washing intensive care patients. “Those infections were due to inadequately preserved cosmetics” observed David Steinberg, Steinberg & Associates, Inc. [14,19]. In 1947, in New Zealand, unsterilised talc caused 25 cases of Tetanus, and 4 fatalities 
While it would be great if a “natural” alternative for preservation existed, the truth is there isn’t one that is effective enough. To keep certain types of products free of bacteria, mold and yeast and to make it a product that is safe for your use, a chemical preservative is necessary
Let me repeat, if you make your products FRESH every 3 DAYS, and store them in the refrigerator, then, and ONLY then, can you avoid using preservatives.
BUT PLEASE for your own safety, consider using a safe, paraben based preservative system in ALL your DIY skin care formulations.
The potential harm to your skin caused by bacteria, mold and fungus is enormous, whereas the negative claims about parabens in skin care are debunked.
 Cosmetics Info: Preservative Information. Retrieved [May 22, 2015] from http://cosmeticsinfo.org/ingredient/ethylhexylglycerin
 When should you use a preservative? Sunday, January 29, 2012. Retrieved [May 22, 2015] from http://swiftcraftymonkey.blogspot.co.uk/2012/01/when-should-you-use-preservative.html
 FDA/CFSAN -- Cosmetics Handbook for Industry US Food and Drug Administration Center for Food Safety and Applied Nutrition. FDA/IAS Booklet. Wahington, DC: 1992.
 Linda B. Sedlewicz, BS, Cosmetic Preservatives: Friend or Foe?, Skinmed. 2005;4:98-100. Retrieved [May 23, 2015] from: http://www.medscape.com/viewarticle/502370
 Elsner P, Merk HE, Maibach, eds. Cosmetic Controlled Efficacy Studies and Regulations.Stuttgart, Germany: Springer Verlag; 199:275-290
 . United States Environmental Protection Agency’s Design for the Environment [DfE], www.epa.gov/dfe.
 Natural Products Association. Natural Home Care Standard 020910v01.doc www.NPAinfo.org.
 American Chemistry Council Biocides Panel. 2010. Benefits of Antimicrobial Pesticides in Public-Health and Industrial Uses.
 Beth Ann Browne, Phil Geis, Tony Rook, CSPA Preservative Defense Task Force: Conventional vs. Natural Preservatives
 Browne, B.A. 2010. “The Influence of Global Regulatory Requirements and Pressures on Preservative Choices for Consumer Products.” May 6, 2010. Consumer Specialty Products Association Mid-year Meeting. Chicago, IL.
 US EPA Reregistration Eligibility Decision [RED] Flower and Vegetable Oils. EPA 738-R- 93-031. Dec 1993.
 Bleasel, N., Tate, B., and Rademaker, M. 2002. Allergic contact dermatitis following exposure to essential oils. Australasian Journal of Dermatology 43: 211-213
 Perry Romanowski, Natural Cosmetic Preservative Questions Answered, 12/02/2014, Retrieved [May 24, 2015] from http://chemistscorner.com/natural-cosmetic-preservative- questions-answered/
 Reviews of 27 Preservatives, Retrieved [May 24, 2015] from http://www.makingskincare.com/preservatives/
 Preservatives: Grapefruit seed extract [GSE] is NOT a preservative. Saturday, October 16, 2010. Retrieved [May 23, 2015] from http://swiftcraftymonkey.blogspot.com/2010/10/preservatives-grapefruit-seed-extract.html
 Coily by Nature: The Truth About Natural Preservatives, Retrieved [May 24, 2015] from http://www.coilybynature.com/preservatives-the-truth-about-natural-preservatives/
 Treasured Locks: The Truth About Preservatives Including Grapefruit Seed Extract and Parabens, Retrieved [May 24, 2015] from http://www.treasuredlocks.com/trabpringrse.html
 Perry Romanowski, Why are there preservatives in cosmetics, 02/09/2012. Retrieved [May 24, 2015] from http://chemistscorner.com/why-are-there-preservatives-in-cosmetics/
 Tom Branna, Preservative Market Update: A high profile health issue puts preservatives in a good light, but regulators, consumers and many marketers continue to search for alternatives to traditional systems. Published April 30, 2008. Retrieved [May 24, 2015] from http://www.happi.com/contents/view_features/2008-04-30/preservative-market-update-85454/
Quick guide to our preservatives:
For facial washes, body washes, and shampoos: EK300
For acidic creams/lotions (Vitamin C): EK300 or EPE9010
For alkaline creams/lotions (MAP): EPE9010