SILICONES IN COSMETICS: RISKS & ALTERNATIVES
As consumers increasingly prioritize sustainability and eco-friendliness, many have turned to silicone as an alternative to traditional plastic products. But are these compounds really “greener” because they are derived from silica and don’t produce microplastics? And did you know that Silicones in their liquid form are widely used to formulate personal care products?
In this article, we will focus specifically on the liquid form Silicones used in product formulations. While personal care formulators often appreciate the low-cost value add these compounds bring to skincare, hair care, and makeup products, consumers have grown accustomed to the instant gratification provided by the long-lasting wear, improved sensorial experience, and optical aesthetic effects. However, upon closer examination, the question remains: are these “benefits” truly worth it? We think you should be the judge. Our aim is simply to provide the information we have found so that you can make an informed judgement on Silicones and their safety.
HISTORY OF SILICONES
Silicones were originally developed as a synthetic substitute for natural rubber during World War II, when the Allies faced a shortage of the material. Their versatility and ability to be used in a wide range of applications, from insulation to adhesives and sealants, made them a popular choice across industries. Today, silicones are among the most widely used family of materials in the world, found in everything from pharmaceuticals and medical supplies to automotive and aerospace products, foods, beverages, personal care and toys. Silicone compounds are readily available materials that come in both solid and liquid forms. The liquid form Silicones are the class often used to formulate cosmetic products.
There is a common misconception that Silicone is as a natural material because it is derived from the compound silica found in rocks such as sandstone. However, to create silicone, the silica must undergo a complex heating and distillation process that breaks down its molecules until the silicon element can be extracted. This element is then combined with oxygen molecules to produce the final material. Despite being derived from a natural source, silicone is not a natural product- it is a synthetic polymer and includes a mix of chemical additives that are derived from fossil fuels.
SILICONES IN COSMETIC PRODUCTS
In 1953, the use of silicones in skin care products began when Revlon introduced a hand cream called Silicare. Marketed as a protective layer, the product was promoted for its water-repellent properties and ability to form an "invisible glove" to shield hands. Later, the 1980s saw a significant expansion in the use of Silicone materials in all segments of skin care, enabling entirely new textures and solubility characteristics that were not possible with conventional materials. In the mid-1990s, Silicones were introduced into makeup formulations, allowing manufacturers to claim that their products could last all day. By using volatile silicones that evaporated, leaving a film of Silicone resin to hold the pure pigments in place, cosmetic brands could promise color adhesion to lips for up to 10 hours.
More than 50 years since their introduction to skin care, Silicones remain a staple ingredient in the beauty industry, with over 50% of all new cosmetics launched in the last decade containing at least one type of Silicone. It is estimated that the annual production of cosmetic Silicones has reached 8-10 million tons per year. It is important to note that because Silicones are a class of ingredient- you will not see them listed on the ingredient list. Therefore, it’s important to familiarize yourself with some of their common names so you can identify them in your product choices.
Silicones have long been recognized by formulators as multifunctional ingredients that offer a variety of desirable attributes to cosmetic formulations. With their unique chemical and physical properties, these versatile materials are widely used for their sensory and texture-enhancing properties, providing a smooth, non-oily, and non-tacky feel to skin care products. They can act as film formers that can last 8 to 10 hours making the suitable for long-lasting makeup and waterproof products. They help spread pigments and other particles evenly on the skin, providing optical effects that temporarily improve skin texture and mask the appearance of pores and wrinkles.
From a technical point of view, Silicones are very useful in the emulsification process, improving product stability and acting as a booster for sunscreens. They help ingredients penetrate the skin faster, while locking in moisture content and plumping the skin temporarily. Silicones are used in hair care products to reduce static and frizz, smooth cuticles, and provide shine, thereby enhancing manageability. They also protect hair from heat damage caused by styling tools.
In the beauty industry, there is a large misconception that instant gratification equates to efficacy and this is especially evident in the use of Silicones. While these ingredients provide an immediate improvement in the appearance of the skin and hair, they are not beneficial in the long run. Of particular concern is how difficult Silicones are to wash away after application and the issues they cause when they linger behind on our skin and hair. They can clog pores and trap bacteria, dirt, and impurities, leading to the formation of blackheads and blemishes. Additionally, they can dehydrate the skin because the barrier they form can prevent the entry of moisture. This can lead to dull, wrinkled skin that lacks elasticity while also dehydrating the skin and affect its pH balance. Similarly, Silicones used in hair care can accumulate in the hair, leaving it lank, lifeless and heavy.
SAFETY OF SILICONES
Recently, the high world-wide production rates of Silicone put a spotlight on these compounds motivating researchers and organizations to study their safety. Since then, scientists have found large quantities of Silicones scattered in the environment from wastewater, waste gas and waste solids. The seriousness of this issue became highly apparent when a study named Global Distribution of Linear and Cyclic Methyl Siloxanes in Air was published by in 2011 by Genualdi, et al. It showed that Silicones are scattered across the environment in all parts of the world, including the Artic region. The report also suggests that the more elevated concentrations found near urban areas likely due to the use of personal care products.
In terms of environmental impact, some Silicones are readily biodegradable, but others can persist in the environment, accumulate and be toxic. The factors influencing whether a Silicone will biodegrade or not can also depend on where it ends up. For instance, on land one type of Silicone may be broken down more easily but the same may not be true in our waterways or it may not be biodegradable at all.
Since Silicones can be found in rinse-off products, they have recently raised concern about their impact on the aquatic environment. They can accumulate in aquatic organisms over time and potentially cause harm to their health and reproduction. Siloxanes, which are the building blocks of Silicones, have been shown to cause toxicity to aquatic organisms, including altering their behavior, growth, reproduction, and even causing mortality at high concentrations. Furthermore, siloxanes can also impact the food chain as they can be passed from smaller organisms to larger ones, potentially increasing their concentration and toxicity at higher trophic levels.
Moreover, studies also show that siloxanes, may have the potential to accumulate in the human body over time, which could lead to long-term health effects and several studies have reported on the toxicity associated with siloxanes in laboratory animals. Others have reported that they are carcinogenic and toxic to the nervous, reproductive, and immune systems of animals. Ongoing research suggests that siloxanes can disrupt hormone function, cause developmental and reproductive toxicity, and damage the liver and kidneys. More recent research is focusing on their ability to overcome the barrier of the skin. As a result, some Silicone ingredients have already been banned or restricted from use in cosmetics in the EU.
ALTERNATIVES TO SILICONES
For formulators, alternatives to Silicones in cosmetic products can be challenging to find and expensive to use but there are plant-based ingredients that can replicate some of their benefits. These natural alternatives are often made from vegetable-based building blocks which are safer for humans and the environment.
At Ingredients ®, we formulate our products using 8 or less, science-backed plant-based ingredients in high concentrations without compromising on the sensorial experience often provided by enhancers such as Silicones. We take great care to curate the ingredients in each formula to deliver optimal benefits and results. Here are some of the alternatives we use:
Humectants: Humectants pull moisture to the skin and trap it there, increasing hydration. Tremella Mushroom, Aloe, Vegetable collagen and Glycerin are natural humectants.
Oils: Oils made form Squalene, Abyssinian, Jojoba, Baobab seed, Marula seed, Broccoli Seed as well as Coco Caprylate -a fatty molecule that can come from plants all moisturize and help the skin retain moisture. Similar to dimethicone, they also are lightweight and noncomedogenic.
Clays/Starches: Natural clays, tapioca or arrow root starch can absorb excess oil from the skin, helping it stay matte throughout the day.
Colloidal Oatmeal: Made from ground oat grains, this emollient can soften and smooth the skin. It is FDA approved it as a skin protectant, and a 2020 study found that a 1%. colloidal oatmeal eczema cream significantly improved the skin’s pH, barrier function, and hydration.
TAKE AWAY
At Ingredients®, we believe that being aware of the potential environmental and health impacts of Silicone and other cosmetic ingredients can help consumers make more informed choices about the products they buy and use. Reading ingredient labels and choosing products that use environmentally friendly and non-toxic ingredients is an effective way to reduce our impact on the environment and our exposure to potentially harmful substances. You can also opt to shop at retailers that specialize in silicone-free and non-toxic beauty products such as Beauty Heroes® when you are looking to make more conscious choices.