Study of cadmium, lead and tin distribution in surface marine sediment samples from Ria de Arousa (NW of Spain)

In this work a study of the Cd, Pb and Sn content in marine surface sediment from the Ria de Arousa has been realised. For this, 21 sediment samples were taken in triplicate, lyophilised and sieved, and the fraction <63 μm was taken for analysis. The samples were prepared in a form of slurries and analysed by electrothermal atomic absorption spectrometry. The concentration ranges obtained were 90-990 μg kg -1 Cd, 26.5-91.3 μg g -1 Pb and 5.0-20.8 μg g -1 Sn. The highest concentrations of these metals are in the inner part of the Ria, near to the port and urban nucleus such as Vilagarcia or Rianxo, and decrease toward the mouth of the Ria.