Bamboo vs plastic vs electric: an honest comparison

What the life-cycle assessment actually found

There is one widely cited piece of quantitative evidence here, published in the British Dental Journal in 2020. It compared four toothbrush types — a traditional plastic manual, an electric, a plastic manual with replaceable heads, and a bamboo manual — using life-cycle assessment over five years, counting raw materials, manufacture, transport, use and disposal.

Three findings, quoted rather than paraphrased:

• The electric toothbrush “had the greatest impact in 15 out of 16 environmental categories”.
• “The bamboo and replaceable head plastic toothbrushes had the lowest impact in all categories.”
• “The climate change potential of the electric toothbrush was 11 times greater than the bamboo toothbrush.”

The middle finding is the one worth sitting with, because it doesn’t suit us. A plastic brush with replaceable heads did as well as bamboo. If your priority is the measured environmental footprint rather than plastic specifically, keeping one handle and replacing only the head is as good a strategy as changing what the handle is made of.

Two caveats, in fairness to bamboo. The study covered four types and natural-bristle brushes weren’t among them, so there is no comparable figure for what we make. And an LCA measures things like carbon and water; it does not directly capture “this object still exists in two hundred years”, which is most of why people care about plastic in the first place.

Electric brushes

Electric is the clear loser environmentally, and it’s not close. A motor, a lithium battery, a charger and a circuit board carry a far larger manufacturing footprint than a moulded stick, and at end of life the body is e-waste rather than general waste.

The waste unit is also different in a way people miss: you replace the head every few months, so an electric brush produces a steady stream of small plastic heads for as long as you own it.

That is a statement about environmental impact, not about your teeth. Some people clean better with an electric brush, and if a dentist has recommended one for a specific reason, that reason outranks anything on this page.

What we’re not putting in the table

Cost per year. We’d have to keep a price table current across brands we don’t control, and a stale price table is worse than none. Ours is exact and you can check it: a four-pack is $44.99, which at the recommended three-month replacement cycle is roughly a year of brushing. A supermarket multipack is cheaper per brush; an electric costs more upfront and then keeps charging you for heads.

Weight of plastic avoided. We looked at publishing this and couldn’t do it honestly — we haven’t weighed the bristle tufts separately from the handles, so any figure would be a guess dressed as data. What we can tell you is that when we weighed brushes for our toothbrush waste estimate, a bamboo brush and a plastic one both came in at 17 grams. Switching handles doesn’t reduce the tonnage. It changes what the tonnage is made of.

So which should you buy?

Honestly, the biggest variable isn’t in this table. Using a brush for its full life and replacing it when the bristles splay matters more than which of these you picked.

After that, in rough order:

• If you want the lowest measured footprint: bamboo manual, or a plastic handle with replaceable heads. The evidence puts them level.
• If you specifically want less plastic: bamboo beats a refillable plastic handle, because the handle stops being plastic. But the bristles are still nylon unless the brush says otherwise.
• If you want no plastic in the head at all: that means natural bristle, which is what we make — and it isn’t vegan and takes longer to dry.
• If you have an electric and it suits you: keep the body for as long as it lasts. Replacing a working electric brush to save the planet is not a saving.