Trace metal in Scottish estuarine and coastal sediments

As part of the UKʹs National Monitoring Plan (UKNMP) marine sediments have been collected from Scottish coastal and estuarine sites. The samples have been subjected to a total digestion technique and analysed for major (Al and organic carbon) and minor (Cd, Cu, Pb, Cr, Zn, As, Ni and Hg) elements. Normalization procedures have been used to assess whether the concentrations observed represent background or contaminated levels. It is concluded that trace metal concentrations at offshore sites are at or close to background levels. The Clyde and Forth Estuaries are demonstrated to be the most contaminated areas, trace metal concentrations in these estuaries are shown to be more closely correlated to those of Al than to organic carbon or the < 63 μm size fraction.