The element bromine is found principally as a dissolved species in seawater, evaporitic (salt) lakes and underground brines associated with petroleum deposits. Seawater contains about 65 parts per million of bromine or an estimated 100 Tt (110 trillion st). In the Middle East, the highly saline waters of the Dead Sea are estimated to contain 1 Gt (1.1billion st) of bromine. Bromine is also recovered from seawater as a coproduct during evaporation to produce salt.