The Aral Sea in central Asia formed 5.5 million years ago. It is surrounded by 4 deserts.
The Aral Sea was once the 4th-largest lake in the world; unusual in that 2 rivers flowed into it, but none flowed out. A high evaporation rate meant that Aral Sea just managed to retain its size.
In the early 1960s, Soviet planners authorized huge diversions from the rivers feeding the lake to irrigate farms. The land around the Aral Sea became heavily laden with pesticides, and highly vulnerable to erosion from plowing.
What was once the Aral Sea is now a few toxic ponds and a desert the size of West Virginia. The lethal little lakes will be gone by 2025.
The wind blows the polluted dust of the erstwhile Aral Sea for hundreds of kilometers to the south. Those living nearby have fewer diseases from the airborne toxins than those living 400 km away.