LEAD AND CADMIUM IN SOILS AND VEGETABLES FROM URBAN GARDENS OF SALAMANCA (SPAIN)

The Pb and Cd contents of soils and vegetables from 16 urban gardens o f Salamanca (Spain) have been determined. The metals were found to occ ur at concentrations in the ranges 20.1-96.2 and 0.20-0.95 mug/g for P b and Cd, respectively. The mean Pb concentration found was 2.60 times higher than that in natural soils of the Salamanca province, whereas that of Cd exceeded its mean concentration in natural and cultivated s oils by a factor of 2.73 and 2.04, respectively. The Pb and Cd content s of the vegetables (branches) ranged between 4.17 and 52.7 mug/g, and between 0.35 and 3.05 mug/g, respectively. According to these results , Pb and Cd occur at pollution levels in the surveyed gardens. The tot al and soluble Pb (extractable with 1 N ammonium acetate) levels were found to be related to the traffic density. On the other hand, the Cd levels appear to be more closely related to the distance from roadways , as well as to the age of the garden and the flow of visitors.