Cheap, Sustainable Water Filter Made from Seeds and Sand | Arrival Cities |

A few research groups are looking into how to use the seeds from the Moringa tree to clean drinking water. One group, from Pennsylvania State University, is developing a special, antibacterial Moringa sand that it hopes people could easily make at home and use to filter their own water.

"The idea is that as long as people have [ordinary] sand and Moringa seeds, they can clean water," said Stephanie Velegol, a chemical engineer who is leading the Penn State research. Moringa trees are common in many water-stressed regions of Asia, Africa and South America, and one mature tree can produce as many as 15,000 seeds. 

Moringa seeds might generally prove more appealing than chlorine, which many governments now distribute to people who drink untreated water from wells, rivers and ponds.