As inventor Tony Stark, Hollywood actor Robert Downey Jr transformed into superhero Iron Man and now the Oscar nominee is taking action against environmental threats to the planet. 

Downey is looking to sustainable technology to tackle issues like deforestation and microplastics. 

The "Iron Man" and "Avengers" star said he was launching venture capital funds, aiming to "accelerate groundbreaking technologies that are addressing the world's largest environmental challenges". 

Downey's FootPrint Coalition, founded in 2019 and made up of "investors, donors and storytellers committed to scaling technologies to restore our planet".

It has already invested in companies like Ynsect, which breeds mealworms, and Cloud Paper, which makes bamboo toilet paper, among others. 

Now he wants to "quickly mobilise more people and catalyse more capital".

"There's groundbreaking technologies we're going to vet and keep doing what we're doing, finding the best in class and accelerate scaling them up," Downey told Reuters.

"We feel (the funds) is a move towards just a little bit ofdemocratisation in this usually very exclusive space," he added. 

FootPrint Coalition Ventures will have an early and late-stage fund, with a $5,000 quarterly subscription fee and minimum one-year subscription. 

It says it wants to invest in food and agriculture technology, sustainability-focused consumer products and services, energy and transport, materials and industrial tech, education and media and advanced environmental solutions. 

Downey, who took part in a panel about the Arctic at the virtual World Economic Forum yesterday, narrates short videos made by his creative team on the coalition's site, talking about topics like aquaculture and deforestation. 

"I always feel that if you have great content and the community feels that, the audience grows, that helps us with our access to deals and then we get better outcomes," Downey said.