. A new study has put three strains of fungi to work to extract these valuable materials from electronic waste, which could lead to a safer and greener battery recycling system.

Thanks to our thirst for ever-new technology, e-waste is an increasing problem, as tonnes of discarded electronics are dumped in landfills or incinerated, releasing potentially hazardous chemicals into the air, water and soil. In addition, many of the components are made from rare and valuable materials like lithium and cobalt, so finding ways to reclaim them can help take the pressure off limited natural resources.

But even then, separating out important metals often requires solvents and high temperatures. Looking for a greener alternative, the researchers, from the University of South Florida, turned to three strains of fungi: Aspergillus niger, Penicillium simplicissimum and Penicillium chrysogenum.

"We selected these strains of fungi because they have been observed to be effective at extracting metals from other types of waste products," says Jeffrey Cunningham, the project's lead. "We reasoned that the extraction mechanisms should be similar, and, if they are, these fungi could probably work to extract lithium and cobalt from spent batteries."