Lead is used widely in many industrial processes and occurs as an important contaminant in all environmental compartments (soils, water, the atmosphere, sediments and living organisms). Lead contamination may result both from its persistence and from its present and past numerous sources such as smelting, combustion of leaded gasoline, or applications of lead-contaminated media. In 2009, production of recoverable lead from mining operations was 1690, 516 and 400 thousand metric tons by China, Australia and the USA, respectively 1. Lead has four stable isotopes: 204 Pb, 206 Pb, 207 Pb and 208 Pb, the last three with radiogenic origins from 238 U, 235 U and 232 Th, respectively 2-4. Since each source of Pb can have a distinct or sometimes overlapping isotopic ratio range and physico-chemical fractionation processes do not alter the Pb isotopic composition of Pb sources, therefore the use of the lead isotope ratio is referred to as "lead fingerprinting" 2-4. Lead concentration and isotopes have been widely used to trace environmental Pb pollution and to identify the Pb sources 2-4. Lead isotope signatures have been successfully used on the sediment investigations to trace or identify the lead sources 4-7 .
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