(Bloomberg) -- A company in Sweden has doubled sales in a year by selling a $5 toothbrush and has attracted investments despite donating a slice of the profits to charity.

The Humble Co., which is headquartered in Stockholm, started making environmentally-friendly oral hygiene products after its founder, then 22-year-old dentist student Noel Abdayem, saw a way of addressing two of his biggest concerns: how to help poor children look after their teeth and how to reduce plastic waste.

Its bamboo toothbrush is now one of the world’s best selling. It caught the eye of private-equity firm Verdane, which bought into the company in 2018 and now owns a 25% stake through its fund, Verdane Capital IX.

Humble’s success story is further testament to the growing popularity of Environmental, Social and Governance (ESG) investing, which according to some scholars can be traced back to church-affiliated organizations in 1960s Sweden.

“We have committed to investing only in businesses and markets that either align or don’t directly contradict the United Nation’s sustainable development goals,” said Bjorn Beckman, responsible for the investment at Verdane.

Verdane sees plenty of potential in ESG. It recently assumed majority ownership of Momox, Europe’s largest seller of previously-owned products, and has a stake in Mustad, a fishing hook brand that uses less plastics and replaces lead products with tungsten.

Growing Market

Established in 2013, Humble now sells about 2.5 million toothbrushes per month in 20 countries, including in European and U.S. chains like Target and Walgreens. Revenue is set to almost double this year, to about 120 million kronor ($13 million).

It has grabbed 7% of the toothbrush market in Norway and says it has pushed competitors in the environmentally-conscious Nordic region to launch greener alternatives.

Sales still only represent a fraction of the $52 billion global oral care market, however, and big players like Colgate have now jumped onto the bamboo bandwagon.

Abdayem is pleased with the development.

“It’s fantastic because we can’t drive this change on our own,” Abdayem said in an interview in Stockholm.

To contact the reporters on this story: Love Liman in Stockholm at jliman1@bloomberg.net;Hanna Hoikkala in Stockholm at hhoikkala@bloomberg.net

To contact the editors responsible for this story: Christian Wienberg at cwienberg@bloomberg.net, Love Liman, Nick Rigillo

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