How bad for the planet is your toothbrush? Study reveals surprising answer

15 Sep 2020

Image: © magicbones/

Researchers at Trinity have looked at the sustainability of different types of toothbrush, with electric ones not faring too well.

You might not think too much about your toothbrush most of the time, but researchers at Trinity College Dublin (TCD) have collaborated with the Eastman Dental Institute at University College London to see what impact it has on the planet.

Writing in the British Dental Journal, the researchers published findings on what they said was the first lifecycle assessment to measure the environmental consequences of a healthcare product.

In the study, the carbon footprint and human health impact were analysed for the electric toothbrush, the standard plastic brush, the plastic brush with replaceable head and the bamboo brush.

The team found that the electric toothbrush was comparatively harmful for planetary health. In terms of the human health impact of manufacturing processes, researchers also concluded that the electric toothbrush has an impact of 10 hours in disability-adjusted life years (DALYs) for those associated with the process of making it, five times higher than a standard plastic toothbrush. One DALY can be thought of as one lost year of ‘healthy’ life.

Hidden harm of bamboo

Somewhat surprisingly, researchers suggested that the bamboo toothbrush is not the most sustainable option for your shopping list, but rather a normal plastic brush – as long as it is recycled.

They said that a plastic manual toothbrush with a replaceable head and a bamboo manual toothbrush performed better than traditional plastic manual and electric toothbrushes in every environmental impact outcome measure in the study.

“There is not a lot of evidence to show [electric toothbrushes] are more effective unless you struggle to clean your teeth with a normal toothbrush,” said Dr Brett Duane, lead researcher on the study and an associate professor in public dental health at TCD.

“We have also shown bamboo toothbrushes are not the answer. Using them just stops land from being put to better use such as helping biodiversity, or in growing forests to offset carbon emissions.”

Plastic brushes, Duane said, can be recycled and don’t require lots of land or water to grow. However, he added that there needs to be more effort made to keep these brushes in the recycling chain.

“We need a system where plastic toothbrushes can be collected like batteries and then recycled into new products,” he said. “If the plastic escapes the recycling chain, it needs to be able to be easily and naturally broken down into harmless products.”

Colm Gorey was a senior journalist with Silicon Republic