Analyzing dried blood spots to monitor lead exposure in Calabria, the southernmost region of peninsular Italy

Lead exposure in inhabitants of Calabria, the southernmost region of peninsular Italy, was monitored. Calabria has an area of 15, 000 km² and two million inhabitants. Lead concentrations in anonymized residual dried blood spots (DBSs) from neonatal screening tests were measured using graphite furnace atomic absorption spectrophotometry (GF-AAS). DBSs were collected in the capitals of the Calabrian provinces (Catanzaro, Reggio Calabria, Cosenza, Crotone, and Vibo Valentia), Calabrian towns on the Tyrrhenian and Ionian coasts, and in the Sila and Serre-Aspromonte mountain areas. The median lead concentrations in the blood samples were 3.93 μg/dL in the Sila area, 3.32 μg/dL in the Tyrrhenian area, 2.91 μg/dL in Vibo Valentia, 2.76 μg/dL in the Ionian area, 2.69 μg/dL in Cosenza, 2.65 μg/dL in Catanzaro, 2.64 μg/dL in Crotone, 1.69 μg/dL in Reggio Calabria, and 1.52 μg/dL in the Aspromonte area. The lead concentrations were significantly higher (P<0.05) in the Sila area than in the other locations except for the Tyrrhenian area (P=0.229). The difference between the median lead concentrations in liquid whole blood samples from inhabitants of the Sila area (3.4 μg/dL) and Reggio Calabria (2.2 μg/dL) was statistically significant (P=0.002), and the very different lead concentrations that were found in drinking water from the Sila (0.115 μg/L) and Serre-Aspromonte areas (0.016 μg/L) were consistent with the lead concentrations in the DBSs and the geochemical distribution of lead in soils in the region. The results of this study confirmed that analyzing residual DBSs from neonatal screening tests by GF-AAS is a useful way of monitoring lead exposure in a region.