Anything that contains water (ie. creams, gels, lotions, etc) is a paradise for bacteria, yeast, fungi and molds, and the natural sugars in plant extracts are their favorite snack food.  Bacteria is a fact of life in cosmetics, foods and pretty much any organism that contains even a trace amount of water.  David Steinberg has trademarked the perfect saying when it comes to bacteria, “Remember, Preservatives are Safer than Bacteria™”

Whether you want to bury your head in the sand or not, every cosmetic either has a 3 day shelf life or some form of preservative.  If a cosmetic has even a trace amount of water it must be preserved by some method.  There is no such thing as a preservative free cosmetic.  Determining the water activity of your product is the shortcut to deciding if you need a preservative or not.  If you product is bone dry with no water then it does not need a preservative. 

Bacteria require water to grow and the majority of cosmetics contain high enough water levels to easily grow bacteria.  Simply put, bacteria require water to support life and if you have enough water it will thrive. Gram positive and gram negative bacteria prefer slightly basic conditions pH 7.5 and warm temperatures 37 degrees Celsius (98.6 degrees Fahrenheit.)  All gram negative bacteria are disease producing.  The good guys are the gram positive bacteria.  No bacteria can grow very well at pH of 8.5 to 9.  Fungi, yeast, and molds prefer acid conditions (pH 5.5-6) at room temperature to multiply. 

Cosmetic products must be preserved for two main reasons.  Insurance companies would never cover unpreserved products and the FDA requires that products are not “injurious to user under conditions of customary use because it contains, or its container is composed of, a potentially harmful substance” and they may not “contain filth.”  Products are not required to be sterile but they may not be contaminated with a pathogen all other counts must remain low and remain that way under foreseeable consumer use.  The products must be tested for adequacy of preservation during the development of the product and each batch tested before released for sale.

Many natural substances offer some antibacterial benefits.  Certain essential oils, like Tea Tree, Thyme and Oregano at high concentrations can be helpful with some strains of bacteria.  Unfortunately, your bathroom, purse, car, or desk drawer is not an ideal condition natural cosmetics. Steam, heat, direct sunlight and other adverse conditions help encourage bacterial growth and most "natural preservatives" can't be used in strong enough concentrations to fight contamination without running the risk of skin irritation or allergic reactions. Others are useful only against certain strains of contaminants and for limited amounts of time.  While Vitamin E, Neem and Rosemary Oleoresin Extract (ROE) work wonders at keeping oils from turning rancid, they don't protect against all forms of gram-positive, gram-negative bacteria and yeast which are common in unprotected cosmetic products.

The research and testing has been done recently on why broad spectrum preservatives are an absolute necessity in cosmetics.  It's been done on a lotion using 1% tea tree essential oil as the "natural preservative system" under perfectly sterile conditions.  The product looked, smelled and felt perfectly normal and safe, but the pictures below show the results of the micro-test that we ran on her product after 3 days.  A visual inspection of the lotion was not enough to know that the lotion was full of bacteria and yeast.  Yuck!

    

The first photo is of the lotion itself which showed no visual signs of the yeast and mold that was growing inside of it.  The product smelled just as fresh as it smelled on the first day.  This is why you need preservatives!

Broad-spectrum preservative can be used to boost the preservative action of the natural ingredients, providing protection against a broad range of bacteria, microbes, yeast, fungi and molds. Bacteria can break down ingredients in a product, making it less stable and effective, as well as posing some serious health risks for which you, as the seller, can be held liable.  It is dangerous to sell food at a local fair that you knew had mold growing on it the day before, right? So why sell any personal care product to the public that you know is not properly preserved.  Not only is it dangerous to sell cosmetics that are not properly preserved, it is illegal.

The standard preservative system includes several natural inhibitors along with broad spectrum preservatives is used to prolong the shelf life for a minimum of 12 to 24 months or more. Our system is accepted by the governments of all states and countries including the EU and Japan. Some of the natural inhibitors and antioxidants we use are Tocopherol (Natural Vitamin E), Azadirachta indica (Neem) Oil, Rosmarinus officinalis (Rosemary) Leaf Extract, Salix nigra (Black Willow Bark) Extract (not White Willow Bark which does not have the same effect).  In some cases we use a blend of Essential Oils, Potassium Sorbate, Citric Acid, Usnea barbata (Usnea Lichen) Extract as well.  As you know, no preservative system is fool proof and so proper handling is vital. We suggest a dark, cool, dry place out of direct sunlight and avoid contact with non sterile objects like your fingers.

Preservatives are necessary because the water portion of a product is the perfect breeding ground for mold, fungus, bacteria and yeast.  It is only a matter of time and all cosmetics will go bad. What is frightening is that the product might look and smell just fine, but be filled with micro organisms that are dangerous for your skin and health.

Some products may look fine on the outside, but when you run them through micro testing, the bacteria, yeast, fungus and mold count can be off the charts. Other times, the signs of contamination are more visually obvious. Possible signs of a product going bad can be a rancid odor, product separation and visual evidence of mold in a variety of colors. The problem with the visual or smell test is that they can be very deceptive to the untrained nose or eye.  An unstable, under-preserved product can be contaminated by the water in the product, spores in the air, even unseen contaminates in your packaging and the germs on your hands. A good stable preservative system can keep your product safe and free from these microorganisms for years.
 
We are often asked, “Why does brand X not use any preservatives?” or "Why don't you use that "natural" preservative?" And our answer is always the same. As our research has been extensive, it has included testing many chemical, semi-synthetic and natural preservatives on the market today. It has also included running tests on many of those Brand X products you are referring to. In our research there are five possible answers to the question of how Brand X uses no preservative. 

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  1. There is a preservative system on the market with the INCI name of “Fragrance”, which does not disclose the actual ingredients and hides the preservative in the ingredient itself which acts like a broad spectrum preservative and is used in some of the biggest "natural" lines on the market.
  2. There are many products on the market that failed USP and CTFA Challenge Testing and grew yeast, mold, bacteria and fungus quickly. And when asked why they are still making the efficacy claims they are, the manufacturers simply state that "They passed OUR testing requirements."
  3. They do not fully disclose their ingredient list. This is common of all size companies that mislead their customers, thinking they are protecting their formulas. Their products do not fail micro tests, showing the amazing abilities of broad spectrum preservation yet, they do not have any ingredient listed that has any preservative properties at all. We find that odd at best.  This is a highly illegal method of hiding preservatives but extremely common.  The Federal Food, Drug and Cosmetic Act states that a product "may be deemed misbranded (Sec. 602) for reasons of: 1. False or misleading label. 2. Falure to state prominently and conspicuously any information required by or under the authority of this act. 3. Misleading container presentation or fill."
  4. They might be using ingredients that do not require preservatives. For instance a product that does not contain water might not require preservatives, only an antioxidants such as Vitamin E.
  5. They could be using extracts in one or two different methods. Tinctures used at the right percentage create an effective preservative option. But be careful as many extracts are made in a propylene or butyl glycol base and are themselves preserved with parabens, triclorisan or urea but not disclosed as the manufacturer is only required to list it as an extract since they are considered "processing aides". These used at high enough levels without fully disclosing the other ingredients can create an effective preservative system. But be careful you don't give up one chemical for another.

We hope that helps with many of your questions about "WHY PRESERVATIVES" and hope that you make the right choice for the safety of your customers. We believe we have made the right decision for your safety and the FDA agrees with us.