Eco-friendly toothbrush: bamboo handles, nylon bristles and replaceable heads

What an eco-friendly toothbrush usually means

• Bamboo handle: a fast-growing grass, often marketed as compostable or biodegradable. The handle is only part of the brush.
• Bristles: on many bamboo toothbrushes the bristles are nylon, which is a plastic. Some brands describe their nylon as partly plant-derived, and some use other materials. Read the label to see what the maker states.
• Handle finish: some handles are coated or sealed. Check what the maker says about the finish.
• Packaging: plastic-free boxes and wrappers are specific claims you can check.
• Biodegradable and compostable: the FTC's Green Guides ask that such claims be clear about where and how the product breaks down. A bamboo handle may break down in a compost system, while the nylon bristles will not, and some makers suggest removing the bristles first. Follow the maker's instructions.

Replaceable heads and electric brushes

Some manual brushes have a handle you keep and a head you replace, which means less material is thrown away each time. Electric toothbrushes use replacement heads, which are also thrown away on a schedule. Some makers and recycling programs accept used heads or brushes, but availability differs, so check the maker's website. We do not say that any specific program or product is available to you.

How often to replace a toothbrush

The American Dental Association recommends replacing a toothbrush or brush head every three to four months, or sooner if the bristles are frayed. That schedule is the basis for the cost calculation below. Ask your dentist what suits you, and see our gentle toothbrush guide for bristle labels.

Our angle: cost per brush, then cost per year

Price per brush is the right unit, and it looks different once you add the replacement schedule. Divide the price of a pack by the number of brushes to get the price per brush. If you replace on the ADA schedule, you buy a few brushes a year, so multiply your price per brush by that number for a yearly cost. For a replaceable-head system, add the handle price once, then the heads. For an electric toothbrush, compare the price of replacement heads over time, not only the price of the brush.

1. Divide the pack price by the number of brushes.
2. Multiply by the brushes you will use in a year.
3. For replaceable heads, add the one-time handle price, then compare.

Buying tips

• Multipacks lower the price per brush only if you will use them before the bristles or handle age.
• Let a bamboo handle dry between uses, and do not leave it sitting in water.
• Check that the bristle firmness label matches what your dentist suggested.
• Compare subscriptions with the same price per brush.