Preservatives in Cosmetics: What, Why, and How?

Today we are going to talk about preservatives in cosmetics. Preservatives are chemical substances or natural ingredients that are added to products such as creams, lotions, and make-up to extend their shelf life and prevent the growth of microorganisms. These additions are essential to keep products safe and effective during the time they are used. But what exactly are they, and what are the pros and cons? Let’s elaborate on this further.

What are preservatives?

Preservatives are essential components in cosmetic formulations. These substances, carefully selected and added in precise concentrations, fulfill a crucial function in ensuring the quality and safety of cosmetic products. Their primary role is to inhibit or eliminate microbial growth, including bacteria, yeasts, and molds, which may naturally be present in the ingredients or could be introduced during production or use.

The necessity for preservatives becomes clear when one takes a closer look at the composition of cosmetics. Many products contain water and nutrients that provide an ideal breeding ground for microorganisms. Without adequate protection, these products can spoil within a few days or weeks, which not only affects the texture, scent and effectiveness, but also carries serious health risks.

The effectiveness of preservatives is not limited to one mechanism. Some disrupt the cell wall of microorganisms, while others affect the acidity or pH value of the product to such an extent that it becomes unfavorable for microbial growth.

The pH value created by preservatives to inhibit microbial growth typically falls within the acidic range. Most preservatives in cosmetics are most effective at a pH between 4 and 5, which creates an unfavorable environment for micro-organisms. This is because most bacteria, yeasts, and molds optimally grow at a pH around 7 (neutral) or slightly basic.

So, a sour environment effectively inhibits their growth and metabolism. Moreover, these acidic pH values are often well tolerated by the skin, as the natural pH of the skin is around 4.5-5.5. As a result, slightly acidic formulations are not only effective against microorganisms, but also compatible with the physiology of the skin.

Would you like to know more about: the correct acidity level of your skin

So preservatives in cosmetics are needed for:

• Protection against microorganisms: Most cosmetic products contain water, which is a perfect breeding ground for bacteria and fungi. Preservatives help to combat these microorganisms and prevent them from spoiling the product.
• Consumer Safety: Users of cosmetic products expect them to be safe. Preservatives ensure that products remain free from harmful bacteria that could cause skin infections or allergic reactions.
• Extended Shelf Life: Preservatives ensure that products last longer. This means that consumers can use them over a longer period without worrying about spoilage.

Different Types of Preservatives

Below are some commonly used preservatives in cosmetics and their properties.

Parabens, such as methylparaben and propylparaben, have been popular in the cosmetic industry for years. They work by attacking the cell membranes of microorganisms, thereby combating a wide range of bacteria and fungi. Parabens are stable in various products and relatively inexpensive. However, there is debate about their safety. Some studies suggest they could be endocrine disruptors, but the evidence for this is not conclusive. In addition, parabens can cause allergic reactions in some people, especially those with sensitive skin.

Phenoxyethanol is another commonly used preservative. It specifically targets bacteria by damaging their cell walls. The big advantage of phenoxyethanol is that it is effective in small amounts and has no smell. In addition, it remains stable at various acidity levels. A disadvantage is that it can cause skin irritation in some people, especially around the eyes.

Benzoic acid and benzoates naturally occur in certain fruits. They inhibit the growth of microorganisms by blocking their enzymes. These substances are especially effective in acidic products, but work less well in neutral environments. Like other preservatives, they can provoke allergic reactions in some people.

Then there are the formaldehyde-releasing substances. These slowly emit small amounts of formaldehyde, which affects the proteins in microorganisms. They are effective in low concentrations and work for a long time. However, there are concerns about safety, as formaldehyde in high concentrations can be carcinogenic.

Organic acids such as sorbic acid and benzoic acid make products more acidic, which inhibits the growth of microorganisms. They are often of natural origin and work well against fungi and yeasts. However, they are less effective against bacteria and can affect the acidity of products.

Finally, there are the isothiazolinones, which are very effective against a wide range of microorganisms. They disrupt important processes in microbial cells. Although they work in small amounts, they can cause strong allergic reactions. Therefore, their use is strictly regulated.

When developing cosmetic products, manufacturers must carefully consider which preservatives they use. They strive for a balance between effectiveness, safety, and user-friendliness. Meanwhile, research continues into new, safer alternatives that can protect products without adverse effects on health.

Which microorganisms are being combated?

Preservatives in cosmetic products are designed to combat a broad spectrum of microorganisms that can cause spoilage or pose health risks. These substances target various types of potentially harmful microorganisms:

Bacteria: Preservatives are effective against various types of bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa. S. aureus is a common skin bacterium that under certain circumstances can cause infections. P. aeruginosa is known for its ability to survive in aqueous environments and can cause problems in moist cosmetics.

Yeast: Candida albicans is a significant yeast strain targeted by preservatives. This yeast naturally occurs on the skin and in the body but can excessively proliferate under certain conditions and cause problems. Malassezia furfur, associated with skin conditions like dandruff, is another relevant yeast strain being combated.

Molds: Aspergillus niger is a common mold that is effectively combated by preservatives. This mold not only can spoil cosmetic products, but also produces spores that can cause allergic reactions. Penicillium species, which are often present in the environment, are also tackled to prevent product spoilage.

Preservatives in Food

Just like in cosmetics, preservatives play a crucial role in the food industry. They are added to extend the shelf life of products and ensure food safety. Here are some commonly used preservatives in food:

Sodium benzoate (E211): This salt of benzoic acid is indeed often used in acidic products such as soft drinks, fruit juices, and pickles. It is especially effective in an acidic environment (pH less than 4.5) and inhibits the growth of yeasts and molds.

Potassium Sorbate (E202): This preservative is popular in dairy products such as cheese and yogurt, but also in baked goods and wine. It is effective against molds and yeasts and is considered to be one of the safest preservatives.

Benzoic acid (E210): This organic compound naturally occurs in some fruits and is synthetically produced for use in food. It is often applied in acidic products such as sauces, jams, and dressings. Benzoic acid is particularly effective against yeasts and molds.

Other important preservatives are:

Nitrite and nitrate (E250-E252): Used in cured meats to inhibit bacterial growth and maintain the characteristic pink color.

Sulfur dioxide and sulfites (E220-E228): Applied in dried fruit, wine, and other products to prevent oxidation and microbial growth.

Propionic acid and its salts (E280-E283): Often used in bread and other bakery products to prevent the growth of mold.

These preservatives help inhibit the growth of harmful micro-organisms, thereby preventing food spoilage and food poisoning. They contribute to a longer shelf life, which reduces food waste and increases food safety.

It is important to note that the use of preservatives in food is strictly regulated. The allowed quantities and applications vary per country and are determined by food authorities based on extensive scientific research into safety and effectiveness.

Preservatives at Iconic Elements

At Iconic Elements, we carefully select our preservatives to ensure the safety and effectiveness of our products. We use natural benzoate preservatives, specifically sodium benzoate and potassium benzoate. These are known for their mild and effective preservative properties. These ingredients help to keep our products safe and stable without the drawbacks sometimes associated with stronger preservatives.

For more information about our products, visit the Iconic Elements website.