Cosmetic Organic Standard (COSMOS)1 is an international and internationally recognized standard for organic and natural cosmetics. COSMOS accepts five preservatives of Annex VI of the European Directive as molecules present in nature: benzoic acid and its salts, benzyl alcohol, dehydroacetic acid and its salts, salicylic acid and its salts, and sorbic acid and its salts.
The main activity of benzoic acid is antifungal but it shows some efficacy against bacteria. It is ineffective against pseudomonas. Furthermore, its optimal efficacy is at pH levels below three. It is safe in concentrations of up to 0.5%.2
Benzyl alcohol is most effective against Gram positive bacteria. It has some efficacy against Gram negative bacteria and yeast, but is ineffective against mold. It shows poor efficacy above pH 7. It is safe in concentrations of up to 1%, but insufficient data supports its safety when inhalation is the primary route of exposure. Furthermore, benzyl alcohol is one of twenty-six allergen substances whose presence must be indicated on the packaging per the European Directive of Cosmetics.
The activity of dehydroacetic acid is strongest against fungi. It has some anti-bacterial properties but is ineffective against Pseudomonas. It is safe as used in current practices and concentration.3
The major activity of salicylic acid is antifungal but it is more effective against bacteria than benzoic acid. It is not as strong an antimicrobial agent. Salicylic acid should be used only in products where the pH is 4 or lower. It is incompatible with iron salts, poorly soluble in water (but shows solubility in fats and oils), and sensitive to UV light. Salicylic acid is safe when formulated to avoid skin irritation and exposure to the sun.4
Sorbic acid is very effective against mold, somewhat effective against yeast, and ineffective against most bacteria. It shows efficacy at a pH of 4.5 or lower. Being an unsaturated fatty acid, sorbic acid is subject to oxidation. It is sensitive to UV light and will turn yellow in solution. Sorbic acid is safe as a cosmetic ingredient as used in current practices and concentration.5
Posted: November 29, 2011, from the December 2011 issue of GCI Magazine.
Building a skin care brand is both exhilarating and challenging. One of the factors that contributes to both feelings, on a very regular basis, is the truism that the only constant is change. As we have worked to build Alchimie Forever over the past six years, we have changed courses a few times along the way. From medical distribution, we shifted course to spa and specialty retail. From independent sales representatives, we shifted to full-time direct sales representatives, before choosing to partner with Universal Companies as our exclusive distributor. The packaging for our men’s line evolved from jars to tubes. And most recently, we decided to reformulate our products to remove two “controversial ingredients”—parabens and propylene glycol. The latter change involved significant internal debate for us, as it has for our industry as a whole in the past few years.
The following is one brand’s perspective on the debate about “controversial” ingredients. We will:
provide an overview of why certain ingredients have developed a bad reputation;
discuss available scientific data that either supports or refutes such a reputation; and
present which, if any, alternative ingredients are available to the industry.
In response to some activist groups perpetuating ingredient myths, we aim to separate fact from fiction, science from the so-called “junk science.”1 And most importantly, perhaps, we highlight two independent, sometimes complementary, reasons to change a product’s formulation: science and commerce.
Let’s start with a look at the most talked-about controversial ingredients.
Preservatives: Formaldehyde Releasers and Parabens
Preservatives inhibit the development of microorganisms in cosmetic products by damaging the internal structures and cellular membranes to produce cell death. They serve to enhance the safety of cosmetic products, enabling products to remain bacteria-free over the long- term (three to five years). The controversy over the use of preservatives stems from the fact that anything that kills microorganisms is potentially toxic to mammalian cells. What needs to be taken into consideration is the concentration of these preservatives, as well as the contact time and point, which are determined to avoid side effects.