Heavy metals in urban channels sediments of the city of Aveiro, Portugal

Citation

Pastorinho MR, Telfer T & Soares AMVM (2004) Heavy metals in urban channels sediments of the city of Aveiro, Portugal. Fourth SETAC World Congress: 25th Annual Meeting in North America, Portland, OR, USA, 14.11.2004-18.11.2004. http://abstracts.co.allenpress.com/pweb/setac2004/termindex/author-T.html

Abstract
The quantification of trace metals in surface sediments collected in the urban channels of the city of Aveiro was performed using GF-AAS (Graphite Furnace Atomic Absorption Spectroscopy). The city is located in the shores of the Ria de Aveiro, a coastal lagoon, and until a recent past tidal floods would rise from the channels that run through the city and partially submerge some of its oldest areas. These events alongside with the impacts associated with urban centres have concurred to create accumulation of metals in the sediments. Six metals were identified and quantified: aluminium, cadmium, chromium, copper, lead and zinc, alongside with calculations of organic carbon contents and C/N ratios. Despite of the generally high concentrations measured, only two metals (Pb and Cu) in two sampling stations registered levels higher than those of the OSPAR guidelines. Organic enrichment is generalized with consequent reflections on the C/N ratios. Good correlations were established between aluminium and Cr>Zn>Cd, but none was found for copper or lead. Good correlations were establish between organic carbon and the analysed metals (Zn>Pb>Cd>Cu>Cr).

Keywords
urban; heavy metals; organic carbon; sediment