During the mid-20th century, Soviet engineering projects diverted the Amu Darya and Syr Darya rivers to irrigate vast cotton fields in Central Asia. Deprived of its primary water sources, the Aral Sea—once the fourth-largest inland body of water in the world—began to shrink catastrophically, losing over 90 percent of its volume by the late 1980s. As the water evaporated, it exposed a vast, barren desert floor spanning over 50,000 square kilometers, now known as the Aralkum Desert.
This exposed seabed was not merely dry sand; for decades, agricultural runoff containing heavy industrial fertilizers, organochlorine pesticides like DDT, and defoliants had accumulated in the lake's sediment. When the water evaporated, these hazardous chemicals crystallized alongside concentrated salts, creating a fine, toxic crust across the dry basin. High-velocity atmospheric winds frequently sweep across the flat terrain, generating violent salt-dust storms known as 'solonchaks'.
These storms lift tens of millions of tons of toxic salt and pesticide dust annually into major atmospheric dust vectors. The particulate plumes travel thousands of kilometers, reaching as far as Greenland's glaciers, the forests of Norway, and the peaks of the Himalayas. Regionally, the toxic dust storms caused severe ecological degradation, collapsing surrounding agriculture and triggering severe public health crises in Karakalpakstan, including elevated rates of respiratory illness, esophageal cancer, and kidney disease.