Miron Onsarigo

Miron Onsarigo grew up in Kisumu, where breathing in vehicle fumes was simply part of daily life. Over time he saw friends and relatives fall ill from conditions linked to polluted air, and he came to see that what his community accepted as normal was in fact a public health problem worth solving. That frustration led him to co-found HewaSafi, whose name means clean air in Swahili.

Working with classmate Fredrick Njoroge Kariuki at M-PESA Foundation Academy, Miron helped design a filter that clips onto the exhausts of matatus and motorcycle taxis. Instead of costly metals, it uses layered materials such as maize cobs, coconut shells, other agricultural waste and a living algae component. Using sensors provided by their school, the pair tested the device on five matatus on Thika Road and reported reductions of about 93 percent in fine particles and 42 percent in carbon monoxide. Their prototype costs around KES 16,000, far below typical replacement filters.

The work earned the team the Africa regional title of The Earth Prize 2026, one of seven regional winners chosen from a global field of teenage innovators, with USD 12,500 to develop the product. The team plans a HewaSafi family of Lite, Pro and Mobile models sold on instalment plans so drivers can afford them, starting with Eastleigh Matatu SACCO. Miron's focus remains on the communities in western Kenya that first inspired him.