Best of Bristles

By Charlie Hartley

Around 140 million plastic toothbrushes end up in landfill in the UK every year. Switching to an eco-friendly, zero-waste toothbrush can bring that number down to zero. Whilst there are biodegradable toothbrush options available, there is some controversy surrounding bristles. You can make bristles from either nylon or animal hair. There are no other options, makeing things difficult if you have a plastic-free and animal-free lifestyle. Let's look at the available options in more details.

Animal hair bristles 

The first proper toothbrushes were created in China around 600 years ago. Traditionally, the bristles of the toothbrush would be made with hog or horse hair. Animal hair was necessary, as it is soft enough for the teeth whilst being durable enough to form bristles. The body of the toothbrush would be made of bamboo or bone. These pre-plastic toothbrushes were biodegradable. However we believe animal hair bristles are not particularly hygienic: they have a tendency to retain bacteria. Nor are they cruelty-free.

First nylon toothbrushes

The plastic based toothbrushes we use today emerged in 1938, with the invention of nylon. The manufacturing of nylon greatly expanded during the Second World War when the widespread commercial use of plastic took off.

The rise of nylon allowed us to dispense with animal hairs on our bristles. Nylon also proved to be soft yet durable enough for bristles, and we’ve been brushing with it ever since. The fact that it’s super cheap and more hygienic than pig hair helps, too. We outlined the problem with plastic toothbrushes in last weeks’ blogpost.

The difference between nylon 6 & nylon 4.

Nylon 6 is a widely used plastic that is not biodegradable. Nowadays, most commercial toothbrushes use this type of nylon. Although harder to source and therefore less prevalent, nylon 4 is biodegradable. 

According to a study by the NCBI: “It has been reported that nylon 4 was degraded in the soil and in the activated sludge. The results confirmed that Nylon 4 is readily degradable in the environment. Furthermore, the biodegradability of nylon 4 and nylon 6 blends was investigated in compost and activated sludge. The nylon 4 in the blend was completely degraded in 4 months while nylon 6 was not degraded.”

Why we choose Nylon-4

So, to recap, the only cruelty-free options are nylon based. We have chosen the only biodegradable nylon available: nylon 4. Along with the bamboo body of the brush, our bristles are entirely compostable.