Trace metals in sediments from the "Ria de Huelva"

Abstract

The Ría de Huelva is an estuarine zone into which flow the Odiel and Tinto rivers, polluted by trace metals. Total contents of Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Pb, Cd and Hg were determined in the < 630 and < 63 μm fractions of bed sediments. Total trace metal contents in the coarsest fraction are lower than in the finest, although both are highly correlated for most of the metals, allowing an easy grain size effect correction. Total concentrations of Cu, Zn, As, Pb and Hg are very high, having enrichment factor indexes ranging from 35–171. Important proportions of these are in easily soluble and reducible physico‐chemical forms, which are readily available for living organisms.