Benin company harvesting plants that could soak up oil spills
A company in Benin is harvesting water hyacinths which can be used to soak up oil in an easy, cost-effective way.
If left unattended the plant reproduces incredibly fast, so the harvesting also helps maintain a balanced ecosystem.
However it has not yet been possible to scale up the process so that it can be used to deal with major off-shore oil spills.
The BBC's Questions d'Argent programme went to meet the founder to see how it all works.
Video produced by Francois Wibaux and Franck Noudofinin.