Lead isotopic fingerprint in human scalp hair: The case study of Iglesias mining district (Sardinia, Italy)

Abstract

The Sulcis-Iglesiente district (SW Sardinia, Italy) has been, until recently, one of the most important Italian polymetallic mining areas for the extraction of lead. Epidemiological studies conducted over several decades have indicated this site at high risk of environmental crisis with possible adverse effects on the public health. In the present paper we discuss Pb isotope signatures in human scalp hair and road dust collected from the Sulcis-Iglesiente area in order to trace the exposure of populations to potential Pb sources. A total of 23 determinations (20 on hair samples and 3 on road dust samples) of lead isotope ratios (206Pb/207Pb and 208Pb/206Pb)were carried out. The obtained results were integratewith literature data regarding the total content of Pb in hair samples fromthe same study area. Hair fromchildren living in Sant'Antioco exhibited lead isotope ratios in the ranges 1.152–1.165 for 206Pb/207Pb and 2.101–2.108 for 208Pb/206Pb,while hair samples fromIglesias resulted less radiogenic: 206Pb/207Pb ~ 1.147–1.154 and 208Pb/206Pb ~ 2.106–2.118. These values pointed to a multi-source mixing between the less radiogenic sources, corresponding to the Pb ore deposits, and the more radiogenic sources identified in local background.