In 2014, a crisis took hold in the Michigan city of Flint, once a powerhouse of the US car industry.
The city changed the source of its drinking water to the river which flowed through Flint. The pipes drawing out this water were lead-lined, and lack of investment meant the water treatment plant couldn’t filter the lead out of it. More than 100,000 people were told their tap water was no longer safe to drink.
Gitanjali Rao, a 12-year-old scientist who lives in Colorado, was so concerned by the reports she saw that she decided to do something about it.
She created a cheap home kit that could test for pollutants like lead, and named it after Tethys, the Greek god of clean water. The invention garnered her the America’s Top Young Scientist award in October 2017.
BBC Future caught up with her to see how the device works – and the life of science she plans to lead.
Author: Will Francome
Additional footage: Peter Carolla
Additional editing: Bernadette Young
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