Are silicones good or bad?

The trend to market ‘silicone-free’ products is growing. But why is it that we suddenly want to replace tried and tested substances? After all, the truth is that silicones have been used in the personal care sector and many other industries for decades. So why do we hear about ‘silicone-free’ claims in personal care products, and why are ‘natural’ alternatives to silicones being marketed as safer, more effective options? Even industry analysts sometimes mistakenly believe that silicones are petrochemicals derived from oil. In fact, silicones are synthetic products derived from two of the most abundant materials on earth: sand and quartz.

In personal care, silicones are extremely compatible with a large range of formulation ingredients even with plant-based ingredients, providing formulation flexibility. They have low chemical reactivity and low toxicity, making them ideal for personal care applications including skin and sun care products, body lotions, and make-up. Major developments in colour cosmetics, such as long-lasting lip glosses, were made possible through advances in silicones. Silicones provide a wide array of benefits in skin care products. Perhaps the silicone feature that consumers most appreciate is the smooth and silky feeling they give when they are applied.

In the European Union, the chemicals legislation (REACH) has naturally led to an increased scrutiny of large-tonnage substances used in applications where the potential of harmful exposure to people and the environment is significant. There are some debates about whether silicones potentially accumulate in the environment. The assumption that silicones are not degradable is largely based on a misconception. As silicones were originally designed to be resistant and long-lasting, they are not broken down by biological means in the environment, meaning that they are not attacked by bacteria and bugs in the environment. Nonetheless, silicone cosmetic ingredients are removed from the environmental compartments over time by other mechanisms such as partitioning to air followed by atmospheric degradation (via hydroxy free radicals and UV) and partitioning to sludge in sewage treatment plants.

Changes in cosmetic formulations have historically been driven by consumer demand and to what extent they are available. This is how silicones have gone from a minor position 40 years ago to where they are today. In turn, silicones are now competing with other substances that try to exhibit similar benefits. Understandably, cosmetics manufacturers are constantly looking for ways to innovate and improve the sales of their products in a highly competitive market with short product life cycles. From a marketing standpoint, one way to do this is to take advantage of the current movement towards natural cosmetics. Some consumers are drawn to natural products because they perceive them as safer and healthier: perceptions that impart a feel-good sentiment.

The global chemical industry and its member companies (through the Responsible Care initiative) have pledged to ensure that they behave in a responsible way towards society and the environment. The silicone industry conducts tests extensively, and documents the appropriate intended use for each product in order to ensure the safety of its products. The environmental fate of silicones has been subject to many studies since the 1980s. When present in the environment, silicones ultimately degrade into water, CO2, and silica and/or silicates. Silica and silicates are some of the most abundant natural materials, taking the form of sand, quartz, flint and many others.

AUTHOR:
Dr Pierre Germain, Secretary General,
CES –Silicones Europe, Brussels, Belgium
info@silicones.eu
www.silicones.eu