Between 1840 and 1856, nearly 4 million tons of salt were extracted from the lake. Following the 1856 Treaty of Paris (1856), settled the Crimean War (1853-1856), Russia had to return to Moldova a strip of land from southwest Bessarabia (known as Cahul, Bolgrad and Ismail). As a result of this territorial loss, Russia had no access to the mouths of the Danube, and the exploitation of the salt was stopped.
Following the Treaty of Berlin (1878), Romania was forced to return Southern Bessarabia to Russia. After that, Russians did not resume the salt extraction from the lake.
Sources
Starushenko L.I., Bushuyev S.G. (2001) Prichernomorskiye limany Odeschiny i ih rybohoziaystvennoye znacheniye. Astroprint, Odesa, 151 pp. (in Russian)