Preservatives have always seemed to be a necessary evil. They protect products from developing harmful bacteria, but they are oftentimes irritants or even potentially carcinogenic as well (see the post on why products need preservatives). So I was intrigued by Avène's Tolérance Extreme range, proclaiming that it is preservative, fragrance and surfactant free line of skin care products for very sensitive skins.

So how is Avène able to say look Ma no preservatives and still produce a safe product. It turns out that a packaging company called Promens has developed a sterile closure system for cosmetics products that allows preservatives to be cut out altogether.Called the DEFI system, the tubes somehow stay intact to protect the formula from bacteria that could enter after the product has been opened by the consumer.

Although this isn't the first time that cosmetics have come in small tubes, vials or ampoules (likes Dr Hauschka's Rhythmic Conditioner), but usually these are tiny things that contain enough product for a couple of days. The Promens ones are a little bigger. Its all in the tube's cap. It has four parts to it, including a membrane that rises when the tube is squeezed and resumes its normal position when pressure is released from the tube. These are high-precision parts manufactured to one hundredth of a millimeter.

Now all they need to do is make them out of recycled plastic. In the meantime, hats off to Avene and Promens for a step towards a preservative free future.

As a gratuitous aside, I mention that I was surprised to see, when I checked out Avène's Tolérance Extreme range, that something expressly made for sensitive skins would contain mineral oil, known to cause petrochemical hypersensitivity, triggering serious allergic reactions. Mineral oil is also believed to to cause photosensitivity (encouraging sun damage).

Ingredients in Avene Tolerance Extreme Soothing Cream

Water (Aqua), Glycerin, Mineral Oil (Paraffinum Liquidum), Squalane, Carthamus Tinctorius (Hybrid Safflower) Seed Oil, (Carthamus Tinctorius), Cyclomethicone, Glyceryl Stearate, Sodium Carbomer, Titanium Dioxide.