What Is Silicone and How Is It Different from Plastic?

Many people want to know if silicone contains microplastics, especially since plastic pollution is such a big issue. The simple answer is no-silicone does not contain or release microplastics the way regular plastics do. Silicone and plastic may look and feel similar, but their chemical makeup is very different. Silicone is more stable and does not easily break apart. Knowing these differences helps explain why silicone is considered a safer and more eco-friendly choice in many uses.

Silicone vs. Plastic: What Are They Made Of?

To see how silicone and plastic are different, let’s look at what they are made from:

• Plastic: Made from oil and gas. Its molecules are long carbon chains (polymers), which can fall apart over time due to sunlight, heat, or wear. As plastics break down, they turn into tiny pieces known as microplastics and even smaller nanoplastics.

• Silicone: Made from silicon, oxygen, carbon, and hydrogen. It starts as sand (silicon dioxide), which is turned into silicon and combined with other elements to form siloxane polymers. These have a strong silicon-oxygen chain, making silicone tough, bendable, and able to handle very hot and cold temperatures (-60°C to 230°C). Unlike plastics, silicone doesn’t easily fall apart under normal use.

Table: Main Differences Between Silicone and Plastic

Is Silicone a Type of Plastic?

Sometimes, people call silicone a kind of plastic because both are synthetic polymers, which means they are made from long chains of molecules. However, silicone acts much more like rubber and is used for its rubbery qualities. The big difference lies in the bonds making up silicone, which are much stronger and less likely to react or break down compared to regular plastics. This means silicone is less likely to leak chemicals or break into microplastics. Even though some may group silicone under the large umbrella of “plastic,” it acts very differently, especially when it comes to microplastics.

Does Silicone Create Microplastics?

What Are Microplastics?

Microplastics are very tiny plastic pieces, less than 5 mm across. They come from the breakdown of bigger plastic items by sunlight, weather, and use. Microplastics are everywhere-in oceans, soil, the air, and even in our food and water. They are a growing concern because they can harm animals, enter the food chain, and potentially affect human health.

Can Silicone Turn Into Microplastics?

Under normal conditions, silicone does not break down into microplastics like regular plastics do. Its strong chemical bonds help it stay whole even after years of use. However, extremely strong physical actions or exposure to harsh chemicals could cause it to shed tiny fragments.

A 2023 study in PLoS One tested silicone pacifiers by blending them with an immersion blender and found that this can create very small particles (nanoparticles). Boiling the silicone first led to even more particles when blended. Still, these pieces are chemically different from petroleum-based microplastics, and their effects in nature and the body are not the same.

Research on Silicone Particle Release

The 2023 PLoS One study found that:

• Both silicone and latex pacifiers released tiny particles when heavily blended.
• Silicone’s average particle size was about 129-182 nanometers.
• The chemical makeup of the particles was nearly the same as the original silicone.
• Latex particles showed more chemical changes and were less stable.

When tested on Daphnia magna (a water animal), latex particles were harmful, but silicone particles were not. This suggests that even when silicone does break into small bits, those bits are less likely to cause environmental harm compared to regular plastics or latex.

Table: Silicone vs. Plastic in Particle Release

Comparing Microplastic Risks

• Plastics like polyethylene and polypropylene are major sources of microplastics, especially when exposed to light, heat, or scraping. They can also leach chemicals into food and drinks.
• Silicone does not leach chemicals and rarely sheds micro-sized particles. When it does under unusual conditions, these particles are different from plastic microplastics and seem to cause less harm.

What Makes Silicone Break Down?

Conditions That Affect Silicone Longevity

Silicone’s strong makeup helps it last a long time-sometimes hundreds of years-without breaking down naturally. This means less waste from frequent replacement, but also makes recycling and disposal a challenge.

Some conditions that may cause silicone to break down include:

• Constant or extreme mechanical stress (rubbing, cutting, or blending)
• Long-term exposure to aggressive chemicals
• Not sunlight, as silicone is mostly UV-resistant

The Role of Heat, Acids, and Physical Force

• Heat: Silicone stays strong up to 230°C. Only extreme, prolonged heat well above this might cause it to weaken, but not split into microplastics as quickly as plastic.
• Chemicals: Everyday acids and bases do little to silicone, but very strong chemicals may break it down over time.
• Mechanical stress: Actions like blending or harsh scrubbing can create tiny silicone particles if repeated often and forcefully.

Are Silicone Nanoparticles a Health or Environmental Concern?

Health Risks for People

Silicone is widely seen as safe for human contact. Medical-grade silicone is used in implants and devices and does not cause irritation or toxicity. While plastics can release chemicals like BPA, silicone is chemically neutral and does not leach harmful substances. Even when forced to release nanoparticles, current studies show these are unlikely to harm aquatic life and are less risky than microplastics from regular plastics. However, more long-term studies would help confirm the safety of inhaled or swallowed silicone particles in people.

Environmental Concerns

Although silicone is not a source of regular microplastics, it does not break down or rot in the environment, so waste can build up over time. But since silicone stays whole for so long, it means fewer products need to be made, used, and thrown away compared to single-use plastics. Recycling silicone is possible but may require special facilities, which are not yet common.

How To Use and Dispose of Silicone Responsibly

Tips to Reduce Particle Release and Waste

• Handle gently: Clean silicone kitchen tools with soft cloths, not harsh scrubbers.
• Avoid sharp objects: Don’t cut directly on silicone surfaces or use sharp knives that can tear or gouge.
• Keep within temperature limits: Don’t use silicone beyond its safe heat range.
• Wash less when possible: Especially for dry food storage, to save water and energy.

Alternatives to Silicone That Help Reduce Microplastic Exposure

If you want to avoid all synthetic items, consider these materials:

Summary: Silicone and Microplastics

Silicone is not like regular plastic when it comes to microplastic pollution. Its unique chemical makeup, based on silicon and oxygen, keeps it from easily breaking into microplastics. Research shows that while it’s possible for silicone to release very small particles during extreme use, these are different and far less harmful than regular microplastics.

Silicone is also safer for direct contact with food and our bodies since it does not leach harmful chemicals. However, silicone’s strength as a long-lasting material also means it won’t break down in nature and can add to landfill buildup if not recycled or reused.

Key Points:

• Silicone doesn’t create microplastics under normal use.
• Its particles, if released, are much less damaging than those from plastic.
• Silicone is safer for food, medical products, and baby items.
• While not naturally breaking down, its durability reduces the need for frequent replacements, cutting waste.
• Best practice is to use silicone for as long as possible and recycle through special programs if available.
• Reusing what you own, and choosing glass, steel, or wood when you need new items, also helps the planet.

Choosing and caring for silicone items the right way, and reusing existing products, can help lower both microplastic pollution and total waste, leading to safer and cleaner surroundings for everyone.