When I first heard of 100% castor bean oil toothbrush bristles my bullsh*t meter immediately went off.

How would a bristle, that is very much a solid, be made of 100% oil, which is very much a liquid?

It made no sense to me. Digging deep into the research and studies, I learned like all things in the sustainability realm, the truth is weird and unobvious.

So, what's it made of?

Simplistically, castor bean bristles are made by extracting castor oil from the castor seeds by a mechanical pressing process. The oil is then processed, processed again, processed into a granular form and then processed again into bristle-form.

If it sounds really "processed" that's because it is.

Castor bean oil bristles aren't necessarily more "natural" than petroleum-based plastic bristles however the huge and very important difference is the fact that castor bean bristles are made from castor beans and petroleum-based bristles are made from crude oil.

Crude oil (as in fossil fuels, petroleum, etc) is problematic for a variety of reasons, here are just a few. It’s the major factor in climate change, its fumes are poison to people and animals, mining for it literally destroys the earth and is causing international conflicts and funding wars, oil spills and leaks wreck havoc on our oceans and coastal ecosystems, also, when petroleum-based products break down, they become toxic to the soil, surrounding plant life or marine environment. As if we needed more reasons to have an issue with petroleum, in short, it literally makes our soil and groundwater toxic.

Our castor bean oil bristles, on the other hand, are 100% plant-based (proof!) meaning that when they break down, they break down into nutrients that can be used by plants, not the toxic mess petroleum-based products leave behind.

What about castor bean alternatives?

Given the fact that dentists recommend changing out your toothbrush every 3 - 4 months and that toothbrush bristles are not reusable, that amounts to a whole lot of bristles being tossed away in the course of your lifetime.

Right now, almost all toothbrushes are made with petroleum-based plastic bristles which cannot be composted and will become toxic micro plastics once they start to degrade.

Commercial toothbrush bristles that are made with petroleum not only contribute to demand for crude oil (as that is what petroleum is made from) but because they are so small, they are almost impossible to recycle.

And we should know, our first toothbrush was made with bamboo charcoal and polyester bristles and we were very transparent from the beginning that our bristles contained petroleum-based plastic.

All "bamboo charcoal" bristles (as well as bamboo charcoal floss) contain petroleum as bamboo particles are imbedded into either petroleum-based polyester, as ours did, or petroleum-based nylon to make the bristles or floss.

The white or neon colored bristles that are on most toothbrushes are made of nylon or polyester, which you guessed it, is a petroleum-based plastic as well.

It's really hard to get away from this stuff.

Animal hair is said to be a more sustainable option, however to raise animals to be used as products uses enormous amounts of resources and is not vegan or cruelty free. Animal-based bristles also retain bacteria, moisture and odors making them a less hygienic option.

There have been toothbrush bristles made from PLA which is a corn-based bio-plastic (we actually use PLA for our floss as small amounts have been proven to break down in home composts rather quickly which is a major plus) however, PLA breaks down so quick that it actually starts to fall apart after a few brushes and becomes unusable. We don't know of any companies using PLA at this time for bristles.

Of course, there is one 100% natural and compostable option which is chewing on a neem stick or miswak stick. However, if you want to use a toothbrush these are the options for bristles right now...

Which brings us to castor bean bristles. Of the options available (petroleum-based, animal-based and castor bean-based) we very strongly feel that castor bean bristles are the most sustainable option available at this time.

How do castor bean bristles break down?

Our bristles are certified 100% plant-based which is important because there are a lot of companies out there claiming to be 100% plant or bio-based without the testing and paperwork to back it up. When it comes to greenwashing, trust no one. We will always have the paperwork to back up our sustainability claims and we are asking all other sustainable companies to do the same.

Our 100% plant-based bristles will eventually break down in a home composting environment however we cannot legally call our bristles compostable.

Wait, what? Before you cry "GREENWASHING" (I get it, it's my knee jerk reaction too), read on.

Depending on your country (or state if you live in the US) there are regulations on the word "compostable." These regulations are super important because they protect us from companies lying about their products and claiming they are more eco friendly than they are (it's important to note here, it doesn't stop companies from doing this as many companies simply break the law and don't get caught but at least it tries to regulate.)

The issue with this however, is that in order for something to legally be considered "compostable" it needs to be able to break down in a home or industrial composting environment in a set amount of time, usually around 3 months - although it varies wildly by location.

We're not going to sugar coat, our bristles blow that time out of the water and will probably take about a year or more to break down in your home compost. However, once they do, they will become plant food (as in they will break down and make the soil more nutrient dense) as opposed to petroleum-based plastic bristles which quite literally break down into micro plastics and become toxic to the soil and surrounding plant life.

Breaking down into soil versus micro plastics is the undeniable difference in the end of life between 100% plant-based and petroleum-based bristles.

If you decide to out your castor bean bristles in your compost at home, we recommend pulling out the small aluminum staples at the bottom of the bristles with pliers and recycling them along with your aluminum cans or foil.

As the handle is made of 100% moso bamboo, it can be put in a home compost bin as well. 🙌

One final note on the term "plastic free" in relation to castor bean bristles and why our toothbrush is rightfully considered plastic-free.

Colloquially, when "plastic" is being discussed (let's be real, hated on) we're talking about petroleum-based plastic and for good reason. As mentioned earlier, petroleum-based plastics are made from crude oil and never fully break down. This type of plastic can be recycled, however, every time it is recycled the quality downgrades and virgin plastic can only be recycled a handful of times before it's downgraded so much it has to be sent to the landfill where it breaks down into micro-plastics, contaminating our oceans, soil and ground water.

Castor bean bristles are made out of castor bean bio-plastic. Now before anyone gets all bent out of shape by the word bio-plastic, it’s important to understand the root and the definition of the word.

Plastic comes from the Greek word plastikos, which means to form or mold — think plastic surgery. It’s an adjective used to describe a material’s malleable nature, ie: “plasticity of the mind.”

Scientifically, "plastics are a group of materials, either synthetic or naturally occurring, that may be shaped when soft and then hardened to retain the given shape. Plastics are polymers. A polymer is a substance made of many repeating units."

By this definition, tree sap (yes sap, as in pulled from a tree), tortoiseshell and cellulose from plants are all considered to be plastic.

Given how mind-blowingly broad the scientific definition of plastic is, it is misleading, even irresponsible to put a material made from tree sap or corn in the same category as the synthetic petrochemical substance (ie: petroleum-based plastic) that we commonly associate with the word today.

As a matter of fact, lumping “bio-plastics” in with the same petroleum-based plastic we are commonly referring to when we use that word is something that oil companies are all too happy to see happen.

Bio-plastics threaten the oil industry because the more companies that use bio-based plastics as opposed to petroleum-based plastic, the more demand for petrochemicals dwindles.

"Petrochemicals, which accounted for half of the growth in global oil demand last year, are projected to rise to 70% share of growth by 2040, according to BP. In response to growing concerns about plastic waste, BP modeled oil demand under a worldwide ban on single-use plastics — the first time BP has done that. It would roughly cut in half the growth of oil demand over the next two decades."

Big Oil has every incentive to continue to discredit the plastic-free movement and the bio-plastic industry and they have the time, power and money to do so.

Is castor bean bio-plastic perfect? Nope, not at all.

Is castor bean bio-plastic the best option we have right now for toothbrush bristles? Yep, that's why we chose it.

Are we actively looking into options that are better? Heck yes we are. PHA is something that's on our radar among other options. However, our teeth need brushin' now, and castor bean bristles are the best we have.

We here at Bite are always looking for innovative and sustainable alternatives for the products we use daily in our lives. Sometimes we have something close to a perfect fix (our tablets have very little compromise from a sustainability stand point) and sometimes, the only solution available feels more like the "least bad choice." No matter the solution, we will always be consistent in our reasoning and transparent about the choices we make and why we make them.

Thanks for reading and being part of the plastic-free revolution with us!

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