From Sand to Shelf: Is Silicone Eco-Friendly?

Written by

Inemesit Ukpanah

Last updated

20 March 2024

Silicone has seamlessly integrated into our daily lives, lauded for its heat resistance, pliability, and longevity. Silicone’s environmental footprint is more significant than many realise because it relies on non-renewable hydrocarbons for production and has challenges in recycling and biodegradability. 

This ubiquitous material, found in everything from kitchenware to medical devices, has long been celebrated for its durability and versatility.

Despite its inert nature when incinerated, silicone’s end-of-life treatment is not without complications, necessitating specialised recycling processes that are not widely accessible. Moreover, the recent bans on certain silicone compounds in the EU highlight the growing regulatory and consumer push towards more sustainable materials. 

But as we become more environmentally conscious, it’s important to ask: Is silicone bad for the environment? This article aims to dissect the environmental implications of silicone, examining its production process, longevity, and end-of-life disposal. 

What do we mean by silicone exactly?

Due to its unique properties, silicone, often confused with the element silicon, is a versatile polymer widely used across various industries. It consists of repeating siloxane units (−O−R2Si−O−SiR2−, where R = organic group), varying in consistency from liquid to gel to rubber to hard plastic. 

Silicone is a synthetic polymer made from silica, a natural substance found in sand. Unlike plastics derived from petroleum, it offers a range of benefits due to its chemical composition and physical properties. It can withstand high and low temperatures without degrading, making it ideal for cooking, baking, and food storage products. These items are less likely to scratch, discolour, or break than their plastic counterparts, leading to a longer lifespan and potentially less waste.

The most common form of silicone is linear polydimethylsiloxane (PDMS), known for its oil-like consistency. Silicone’s applications include sealants, adhesives, lubricants, medicine, cooking utensils, thermal and electrical insulation, and personal care products like skincare and hair conditioners. 

To put this in perspective, it is a synthetic polymer of silicon, oxygen, and other elements, often carbon and hydrogen. It’s known for its heat resistance, durability, and flexibility.

Applications of silicone

Silicone’s versatility allows it to be used in a myriad of applications across various industries:

• Adhesives, Coatings, and Sealants: It provides excellent wear, environmental resistance, and thermal stability, making it ideal for construction and manufacturing.
• Cosmetics: Due to its biocompatibility and easy spread, silicone is commonly used in beauty products.
• Photovoltaic and Solar Panels: It enhances the efficiency and longevity of solar panels by acting as a conductive adhesive and encapsulant.
• Electronics: It is a protective layer for electronics, offering resistance to heat, shock, and environmental factors. 
• Food and Medical Industry: It is used in food packaging and processing for its safety and durability. It is also used in various medical equipment, including pacemakers, stents, respiratory masks, and feeding tubes. 

Environmental impact of silicone

The environmental impact of silicone is multifaceted, involving considerations of its production, use, and disposal. The production uses hydrocarbons derived from petroleum, raising concerns about sustainability and carbon emissions. 

This means that the material is not biodegradable, and recycling facilities for silicone are scarce. However, it is less likely to be discarded than plastic due to its durability. While not the most eco-friendly material, it is a far more suitable alternative to plastic, especially in applications where products are used multiple times.

The silicone market in 2023 indicates a continued demand for its products. The growth is due to significant construction, transportation, and electronics contributions. The Asia Pacific region is leading in silicone production and consumption, followed by North America and Europe. 

Despite the environmental concerns, the demand has continued to rise, driven by its superior properties and applications in various sectors.

According to a study commissioned by the Global Silicones Council, silicones generate greenhouse gas emission reductions that outweigh the impacts of production and end-of-life disposal by a factor of 9. This means that for every ton of CO2 emitted, the use of silicones allows for savings of 9 times greater.

What is so bad about Silicone for the environment?

Silicone’s production is not environmentally benign. It involves the use of hydrocarbons derived from petroleum, a non-renewable resource. The process requires high temperatures, which typically consume significant energy, often from fossil fuels. It may release siloxanes at temperatures above 300 °F, harming the environment. Furthermore, it is not biodegradable. 

While it is more durable and less likely to be discarded than plastic, it can persist in the environment for hundreds of years once it reaches the end of its life. Recycling silicone is technically possible but challenging, as it requires specialised facilities that are not widely available.

Silicone’s environmental footprint is multifaceted:

• Production Process: The creation of silicone relies on hydrocarbons derived from petroleum, a non-renewable resource. This process is energy-intensive and contributes to carbon emissions.
• Recyclability: Silicone is notoriously difficult to recycle. Most curbside recycling programs do not accept it, and only a few speciality recyclers handle silicone, limiting its end-of-life options.
• Biodegradability: Silicone is not biodegradable or compostable within a human lifetime. While it may break down into smaller pieces over time, it does not decompose fully, posing long-term environmental risks.

What is the impact of silicone?

The global silicone market was estimated at £ 17.06 billion in 2023 and is expected to grow at a compound annual growth rate (CAGR) of 6.0% from 2024 to 2030. This growth indicates an increasing production and use of silicone, which could exacerbate its environmental impact. 

Total impact per year 

Globally, production and disposal contribute to non-renewable resource depletion, carbon emissions, and landfill waste. However, specific global figures on its total annual environmental impact are challenging to quantify due to the diversity of its applications and the opacity of production data.

Impact per day

Daily, the widespread use of silicone in consumer products leads to incremental contributions to environmental degradation, primarily through energy consumption in production and challenges in waste management.

Impact per usage

Each product use indirectly supports the demand for petroleum-derived materials and energy-intensive manufacturing processes. However, its durability means that, compared to single-use plastics, silicone items may offer a slightly better environmental trade-off by reducing the frequency of replacements.

Top-producing economies of silicone

The silicone market is expected to continue its growth trajectory, with projections indicating a rise from 3.01 million tons in 2024 to 3.87 million tons by 2029, growing at a compound annual growth rate (CAGR) of 5.15%.

In 2022, a few key players dominated the global landscape of production. China led the world in silicon production with a staggering output, significantly outpacing other countries. Following China, Russia and Brazil held second and third positions, contributing to the global supply of critical raw materials for silicone production. However, the production is concentrated in a few countries worldwide, with China leading the pack significantly. 

Leading silicone-producing countries

Silicone is produced in a few countries worldwide. According to the latest data, the top silicone-producing countries are:

1. China: Dominating the global market with a staggering production of 6,000 thousand tons per year, China is the world’s largest producer of silicon.
2. Russia: With 580 thousand tons of silicon produced annually, Russia holds second in the global ranking.
3. Brazil: Brazil is the third-largest producer, contributing 390 thousand tons to the global market.
4. Norway: Following closely, Norway produces 350 thousand tons of silicon annually.
5. United States: The US also plays a significant role in the market, producing 310 thousand tons.

These countries have capitalised on their resources and industrial capabilities to lead the production market.

Here’s a concise overview of the top silicone-producing economies based on the latest data from Statista and Wikipedia:

Key market players

The Asia Pacific region leads the market, holding more than 45.18% of the market share in 2023, primarily due to strong demand from construction, electrical & electronics, and personal care industries. Europe and North America follow, with significant contributions to the market, driven by advancements in construction and the healthcare industry. 

The market is characterised by the presence of several major players, including:

• Shin-Etsu Chemical Co., Ltd.
• Wacker Chemie AG
• Evonik Industries AG
• The Dow Chemical Company
• Elkem ASA
• Momentive Performance Materials, Inc.

These companies are engaged in continuous innovation and strategic expansions to maintain their market positions and meet the growing demand.

Silicone production by region

Silicone consumption by industry

Is silicone eco-friendly?

Silicone isn’t the most environmentally friendly material, but it’s a suitable alternative to plastic. As a robust material, it lasts longer than plastic. Reusing products is an easy way to act more sustainably. For example, silicone menstrual cups or food storage bags can significantly reduce the amount of waste generated over time compared to their disposable counterparts. 

This makes it a good option for eco-conscious businesses and consumers who want to avoid plastic-based products.

Is silicone biodegradable?

Silicone does not decompose or biodegrade in a traditional sense. This material, made primarily from silica found in sand, is celebrated for its durability and resistance to extreme temperatures, but it does not break down easily in the environment. 

Unlike organic matter, which breaks down into natural substances over time, its chemical structure prevents it from being broken down by bacteria or organisms in the environment. This means that silicone products can linger for decades, potentially leading to accumulation in landfills and natural habitats.

While not the perfect material, it is still celebrated as an alternative for reducing plastic pollution and promoting sustainability in various applications. 

However, its non-biodegradability and the challenges associated with recycling present significant environmental concerns. 

Silicone vs. Biodegradable alternatives

When considering the environmental friendliness of materials, it’s essential to weigh their entire lifecycle, from production to disposal. Bioplastics, such as polylactic acid (PLA), are presented as biodegradable alternatives with similar properties to silicone for specific applications like food packaging. 

These materials are made from renewable resources and can degrade much shorter than silicone, offering key environmental advantages. However, choosing between silicone and biodegradable alternatives often involves balancing functionality, durability, and the material’s environmental footprint.

Is silicone toxic?

While silicone is not acutely toxic, it can cause immune responses and toxic effects when it enters the body. Silicone is considered biocompatible, meaning it does not typically cause a reaction when it comes into contact with body tissues. 

However, when silicone particles enter the body, such as through silicone breast implants (SBIs), the immune system can be triggered, leading to potential toxic effects.

According to a review of silicone toxicology by the National Center for Biotechnology Information (NCBI), its compounds have been studied for over 50 years, and the results suggest that they have low toxicity. The review states that silicone fluids with a viscosity of 350 cS were described as having exceedingly low toxicity in a 1950 study. By then-current standards of toxicology, silicone fluids were considered harmless, devoid of any obvious acute toxic potential, and thus presumably safe.

In addition, some studies have raised concerns about certain types of silicones (siloxanes) like volatile cyclic methylsiloxanes D4 (Octamethylcyclotetrasiloxane), D5 (Decamethylcyclopentasiloxane) and D6 (Dodecamethylcyclohexasiloxane) which are persistent, bioaccumulative, and toxic. These compounds have been found to disrupt hormones and act like estrogen, and there is evidence of carcinogenic, mutagenic, and reproductive toxicity in animal studies.

The European Chemicals Agency has recommended phasing out these compounds due to their environmental persistence and potential for bioaccumulation.

For wash-off cosmetic uses, an EU restriction entered into force in 2022 to restrict formulations containing D4 or D5 in quantities of more or equal to 0.1 % w/w. 

Silicone should not be ingested or used at temperatures above 428°F (220°C). 

Can silicone be recycled?

Recycling is difficult, and most recycling facilities do not accept it. Though it can be recycled, the process is not as straightforward as recycling materials like glass or paper.

Recycling is less widespread or streamlined than recycling more common materials like PET plastics or glass. The process usually involves mechanical shredding into smaller pieces, followed by high-temperature processing to break the silicone into reusable polymers. However, these methods are not universally available and can be cost-prohibitive, limiting their application.

The global silicone recycling market was valued at approximately £43 million in 2022 and is expected to grow to about £57 million by 2029, with a compound annual growth rate (CAGR) of 4.1%. Despite the challenges, this growth indicates a rising awareness and effort to recycle the product.

Challenges and limitations

One of the main challenges in recycling silicone is the lack of widespread facilities capable of processing it. This would lead to its potential disposal in landfills, which can take centuries to break down. 

The primary barriers to silicone recycling include:

• Technological Constraints: The robustness of silicone, while advantageous for product longevity, makes it difficult to recycle. Breaking down silicone into reusable forms requires sophisticated technology that is not yet widely available.
• Economic Viability: The costs of silicone recycling, from collection and sorting to the actual recycling process, can be high. Without sufficient economic incentives, industries and waste management facilities may be reluctant to invest in necessary technologies.
• Limited Infrastructure: There is a lack of dedicated facilities for silicone recycling. Most recycling plants are equipped to handle more common materials like plastics, paper, and metals, leaving silicone to either be incinerated or sent to landfills.

However, some companies like (EcoUSA and TerraCycle) and organisations offer take-back programs or specialised recycling services to address this issue. 

Innovations in silicone recycling

Despite these challenges, there are promising developments aimed at making silicone recycling more feasible and efficient:

• Advanced Recycling Techniques: Research into chemical recycling methods, such as pyrolysis and microwave-assisted pyrolysis, offers hope for breaking down silicone more efficiently at lower temperatures, potentially reducing energy consumption and processing costs.
• Closed-Loop Systems: Some manufacturers are exploring closed-loop recycling for silicone waste generated during production. This involves collecting and reprocessing waste silicone into new products, minimising waste and reducing the demand for virgin silicone.
• Regulatory Push and Industry Collaboration: Regulations and industry standards can be crucial in promoting silicone recycling. Initiatives like the Global Silicones Council are working towards better industry practices, including recycling. Additionally, government incentives for recycling infrastructure could lower the barriers to entry for new technologies.

Is silicone sustainable?

While it offers certain environmental benefits over plastic, such as durability and the absence of toxic chemicals, it has drawbacks. The production process is not sustainable due to its reliance on fossil fuels, and the material’s lack of biodegradability and challenges in recycling contribute to environmental concerns. 

The limited infrastructure for silicone recycling means that most end-of-life products are either incinerated, which releases CO2, or landfilled, where they persist without biodegrading. This situation presents a significant sustainability challenge.

Therefore, while it can be a better alternative to single-use plastics, it is not the most sustainable material available, and its use should be considered carefully. 

Silicone vs other materials

Silicone vs Plastic

Silicone is often considered more environmentally friendly than plastic due to its durability and not breaking down into harmful microplastics. Unlike plastic, it does not require mining for crude oil for its production, and it is made from sand, a more abundant resource.

Silicone vs. Bioplastics and Glass

Bioplastics, such as polylactic acid (PLA), offer similar properties to silicone with key environmental advantages, including better biodegradability. Glass, another alternative, is highly recyclable and does not contain chemicals that could leach into food or the environment. However, its fragility can limit its use in some applications.

What are alternatives to silicone?

Considering the environmental impact of silicone, seeking alternatives might be a prudent choice. Biodegradable and compostable materials, such as natural rubber or plant-based polymers, offer sustainable options that break down more easily without harming the environment.

Glass, for example, is more sustainable due to its recyclability and the abundance of natural resources required for its production. 

Bioplastics, made from natural materials, are a more eco-friendly alternative in some applications and can be used in food packaging. They offer several key environmental advantages, including being biodegradable and made from renewable resources.

Environmental impact compared to other materials

Alternatives to silicone

1. Plant-Based Emollients: Products like LexFeel® WOW and LexFeel® N5 MB offer plant-based alternatives to Cyclomethicone and dimethicone. These alternatives are 100% natural and biodegradable, providing similar sensory experiences in cosmetic applications.
2. Natural Extracts: Bamboo Extract, Daikon Seed Extract, and Marula Tetradecane are natural alternatives that can replace silicones in hair care and skin care formulations. These ingredients are bio- and plant-based, effective in providing a smooth, non-greasy feel.
3. Bioplastics: Polylactic acid (PLA) is a bioplastic with properties similar to silicone, especially in food packaging. Bioplastics are biodegradable and are made from renewable resources, offering a more sustainable option.
4. Biophytosebum: Derived from olive oil, this natural emollient is an alternative to volatile silicones and is available in an organic version. It is produced safely, is solvent-free, and is suitable for skin and hair care applications.

Is silicone better than its alternatives?

Silicone is not necessarily better than its alternatives. 

While silicone offers exceptional functionality, durability, and resistance to extreme temperatures, its environmental drawbacks cannot be overlooked. Silicone is not biodegradable and is challenging to recycle, contributing to environmental pollution. 

On the other hand, the alternatives mentioned above provide similar benefits with a significantly lower environmental impact. They are derived from natural or renewable resources, are biodegradable, and do not contribute to aquatic pollution.

Environmental impact compared to everyday items

Silicone’s production is energy-intensive, producing higher CO2 emissions than some natural materials. However, its durability and resistance to extreme temperatures can lead to a lower overall environmental impact over its lifecycle.

However, these findings should be approached with caution due to potential biases and the difficulty in accurately measuring GHG emissions of silicone.

In contrast, plastics, often compared to silicones, contribute significantly to global GHG emissions, accounting for 3.4% of the total.

On the other hand, paper products have a relatively smaller carbon footprint, estimated at less than 1% of human carbon emissions in the US. 

The glass industry also has a notable carbon footprint, with container glass plants in the U.S. reporting direct emissions of 2.92 million metric tons of CO2.

Statistics, facts and figures about silicone

Silicone, a synthetic material composed of silicon, oxygen, carbon, and hydrogen, is known for its versatility and is used in various industries. 

Here are some key statistics, facts, and figures about silicone and its market.

1. Asia Pacific dominated the silicone market with a more than 45.18% share in 2023.
2. The elastomers segment had the largest revenue share of more than 41.89% in 2023.
3. The industrial process segment led the market with over 25.0% revenue share in 2023.
4. Silicones are extensively used in various industrial processes, including antifoaming agents, industrial coatings, and paint additives.
5. In the construction industry, silicones are prized for their high strength and moisture resistance and are used with materials such as concrete, steel, marble, glass, and more.
6. It is used in cosmetics due to its biocompatibility, colour retention, and ability to spread quickly.
7. In photovoltaic and solar panels, silicone’s adhesiveness, environmental stability, and transparency are crucial.
8. It is the second most abundant element in the Earth’s crust.
9. For every ton of CO2 emitted during the production and disposal of silicone, its use results in nine times greater environmental savings, highlighting its potential benefits over plastic.
10. The construction industry, benefiting from silicone’s strength and moisture resistance, is expected to witness a CAGR of 5.7% from 2024 to 2030.
11. North America and Europe have seen a decline in their market shares, with current figures at 16% and 17%, respectively.
12. Southeast Asia and India are expected to grow substantially, driven by industrial expansion and increased market penetration opportunities. 

Frequently asked questions about silicone