France, May 3 -- It's a typical day in a Nairobi neighbourhood. As the sun beats down on dusty streets, children are playing and market traders are shouting out their best prices. As you walk past brick homes and corner shops, something catches your eye - a pile of plastic bottles, bags and wrappers.

This is the end result of a day's consumption, tossed carelessly aside. Plastic waste here is part of daily life.

But for every plastic bottle that ends up on the street, there's someone like Nzambi Matee who is thinking further than the landfill.

To Matee, a materials engineer, waste is both the problem and the solution, waiting to be uncovered.

In a modest workshop tucked away in a corner of the city, piles of plastic waste are being tr...