Is Rubber Biodegradable? It Depends!

I have to admit, rubber is one of those materials I don't think about as often. But it should be! Rubber is so prevalent in our everyday life, from mechanical parts and tires to clothes and shoes… rubber is everywhere.

So when a reader recently asked me if there was such a thing as “eco-friendly rubber” I figured it would be as good a time as any to dive into the big eco-questions surrounding, you guessed it, rubber!

Is rubber biodegradable? Is rubber recyclable? How about compostable? And finally, what are some eco-friendly alternatives to rubber?

What is rubber?

In the simplest definition, rubber is an ecstatic chemical compound that comes from tropical plants. This is referred to as natural rubber. Natural rubber comes mostly from the Hevea brasiliensis tree (which is indigenous to South America). Today, rubber trees can be found throughout Southeast Asia, South Asia, and West Africa, and this is where 90% of our rubber comes from. More than half of all rubber products go into the production of vehicles, airplanes, and bike tires! What is left is made into mechanical parts, shoes, clothing, toys, and other consumer products.

There is also synthetic rubber, but let’s not get too far ahead of ourselves here…

Is rubber sustainable?

This depends mostly on if the rubber in your product is natural or synthetic.

To make natural rubber, the land must be cleared to make room for growing rubber trees. This kind of activity can threaten endangered species and the biodiversity of our forests. The natural rubber industry can also be a big contributor to water pollution as wastewater has been known to cause blockages in local waterways.

The rubber industry is also known to be riddled with corruption and human rights violations. For example, during rubberwood burning, local workers can be exposed to dangerous levels of smoke.  Another example, in Thailand (one of the biggest exporters of rubber) workers, earn as little as 200 baht (US$6) per day. The use of methamphetamine is also common among workers as they are pressured to work faster and faster. Not good.

But it doesn't have to be this way! Companies are starting to commit to sourcing natural rubber from sustainably managed forests that use fewer herbicides and pesticides and treat their workers fairly. The Global Platform for Sustainable Natural Rubber (GPSNR) has been leading the way in the sustainable rubber industry by transforming the natural rubber supply chain into a “sustainable, equitable and fair one”. And as always, you can also look for other certifications like Fairtrade, B-Corp, WRAP, and BSCI to be sure your rubber-based item is ethically sourced.

Pin

Is there a difference between synthetic rubber and natural rubber?

Synthetic rubber, on the other hand, was born out of a need for rubber (tire) alternatives when rubber-producing countries' supply lines were cut off from the US during World War II. While natural rubber is stronger and has less odor, synthetic rubber is more resistant to heat and can be an alternative for those with allergies to natural rubber.

Making synthetic rubber is a little more complicated. Synthetic rubber is made by linking a blend of oil, coal, and other hydrocarbons to create a chain of polymer (plastic) molecules. Like most plastic products, these ingredients are non-renewable and non-biodegradable since they are sourced from petroleum (fossil fuels), a known contributor to climate change.

In the processing of both natural and synthetic rubber, manufacturers can also add desirable features like heat or oil resistance by mixing in different chemical compounds.

Today, natural rubber contributes to less than half of the global production of rubber-based products (13.7 million metric tons per year), the rest is synthetic rubber (15.3 million metric tons per year).

Is rubber biodegradable?

So, is rubber biodegradable? What does that even mean? Well, “biodegradable” means something can break down in the natural environment with or without oxygen. Microorganisms (like bacteria and fungi) will turn the item into carbon dioxide, water, and biomass. To know if something is biodegradable or not, you can look at references like the SCS Global Services certification or the Federal Trade Commission (the FTC). Based on the guidelines set by the FTC, for an item to be labeled “biodegradable” it must completely decompose within one year of disposal.

And just because something is biodegradable does not mean it's compostable! This is because when a product biodegrades, it can leave behind toxic residue that isn’t good for the natural environment.

Natural rubber is made from plants, so it is biodegradable. But since synthetic rubber uses man-made polymers derived from petroleum, these ingredients will persist in the natural environment and be a source of pollution after the item breaks down.

Is rubber compostable?

Pin

“Compostable” refers to items that require both microorganisms and oxygen to break down. Unlike biodegradable items, compostable items will turn into a nutrient-rich organic soil amendment afterward!

There are two types of composting to consider here: residential and commercial. Residential composting refers to composting our organic matter at home. In this case, we have to avoid composting some items like dairy and animal products that might upset the dynamic of our compost bin or cause a foul odor. With commercial composting, equipment like grinders and chippers found in industrial composting operations can break down many more different kinds of organic waste.

Natural rubber is compostable since it's sourced from plants, while synthetic rubber is not. Although it’s worth mentioning here, natural rubber will compost VERY slowly and for this reason, it's better for your rubber-based item to enter the commercial composting stream rather than your at-home (residential) composting bin for this reason!

How long does it take for rubber to break down?

The biodegradability of rubber really depends on the type of product. But in most cases, rubber takes a LONG time to break down.

According to Stacker, tires can take up to 2,000 years to decompose. Latex gloves (often synthetic rubber) will likely take anywhere from a few months to several years to break down. And the rubber soles on the bottoms of our shoes and boots? Those will likely take 50 - 80 years to decompose.

Can you recycle rubber?

Pin

Yes! Most people don't know that rubber products can be recycled. In terms of carbon emissions, recycling four tires is equivalent to saving 28 tons of gasoline! Although to recycle a rubber product, you will have to look for your local recycling facility that accepts rubber waste.

It's also important to note that for rubber to be properly recycled and reclaimed, it must first undergo a devulcanization process. This step helps to break down the elastic bonds so the product can be remolded into something else. This process can involve high heat and toxic chemicals so the impact of recycling rubber isn’t always a full win for the environment.

How should you dispose of rubber?

Beyond recycling, there are three other ways to dispose of rubber.

1. Refurbishing — used rubber products (like tires) can be retreaded and used again.
2. Broken down — used rubber can be ground up to be used for playground surfacing, rubber matting, or garden mulch.
3. Incineration — the oil from used rubber can be extracted during incineration and used to produce energy or fuel.

Eco-friendly alternatives to rubber?

As mentioned earlier, GPSNR has been exploring more sustainable ways to harvest natural rubber. One of these alternatives is to use latex sap! Latex sap is used in the production of natural rubber and can be harvested from different kinds of common plants including milkweed, mulberry, and dandelions! While producing latex sap on a mass scale from dandelions still has a ways to go, there are other ways you can use rubber-based products in your daily life in a more sustainable way.

1. Shoes

The footwear industry is responsible for 1.4% of all global emissions. So picking footwear that contains sustainably sourced rubber can make a big difference. For example, Hunter is a great brand in terms of eco-friendly rain boots. They are making their way towards being 100% FSC-certified and are committed to safe working conditions.

You can also thrift and donate rubber-based footwear! Rubber is a pretty durable product and holds its shape well over time, making it a great option to thrift in my opinion. You can also shop for thrifted rubber items online to expand your selection if you don’t have great thrifted shoes options near you.

Finally, always check to see if your shoes can be repaired first before giving up on them!

2. Cleaning products

Natural rubber gloves are a great addition to any eco-friendly bathroom routine. These gloves by If You Care are made from natural rubber (FSC Certified latex), they are also ethically sourced, don't test on animals, are fair trade certified, and come in recyclable packaging.

Another great option is these natural latex gloves from Full Circle Home! They are made from a mix of nylon and rayon from plant fibers, the cuffs are also 100% cotton. These gloves are BPA-Free, Phthalate Free, and PVC-Free! Full Circle Home is a B Corp Certified company that works with Plastic Bank to reduce, reuse, and offset the plastic they use in their products.

3. Toys

Did you know rubber ducks that we give to our kiddos in the bath are often synthetic rubber or other forms of plastic? It’s true! Kids' toys are among the most plastic-intensive products on the planet!

The company Rose and Rex has rubber ducks made from natural plant-based rubber. They are also colored from natural food dyes so they are safe if your child puts one in their mouth!

Another option is to rent toys from toy libraries! This ensures that products that might be synthetic rubber/plastic have a long lifespan and will be passed on to someone else to enjoy once your child has grown out of that toy (instead of going to a landfill). And of course, you can always check out second-hand toy stores online!

4. School supplies

As I have mentioned, erasers made from natural and not synthetic rubber are the more eco-friendly way to go. Tombow also carries a natural rubber eraser I have also talked about before. It is wrapped in a paper sleeve that can be recycled afterward which is also important to think about.

These are just a few examples of how you can incorporate rubber more sustainably into your daily life! Make sure to check out our GIANT POST on sustainable school supplies.

A final word on biodegradable rubber

So, is rubber biodegradable? This really depends on if the rubber is natural or synthetic. And because over half of all rubber produced is synthetic, there is a good chance your item will not break down in an environmentally friendly way.

When possible, try and buy natural (plant-based) rubber products like shoes, cleaning products, toys, and school supplies! If buying natural rubber isn’t a realistic option for you and your family right now, check out thrifting and secondhand options! Sustainability can be inclusive for everyone no matter your budget.

Pin