Metal

Sediment

Ecology

Biology

Silt

Metallurgy

Materials science

Geomorphology

Mineralogy

Geology

Oceanography

Grain size

Environmental chemistry

Contamination

Environmental science

Soil science

Chemistry

Seawater

Journal of Hazardous Materials

The contamination of sediments can be evaluated from comparison of the current concentration with the estimated background value. Although it is known that grain size affects background concentrations, there have been difficulties in evaluating this effect. The specific surface area of sediments, which can be calculated from the grain size distribution, is introduced as a property index for correlation of background values. The results show that for sandy-to-sandy silt sediments, the background values of metals are expressed in terms of fines content, which can be correlated with the corresponding specific surface area. However, for silty clay or clayey silt sediments, which would have a high metal retention capacity, the level of the background may be constrained by the relatively low concentrations of metals in seawater. Finally, background levels of Zn, Cu and Pb are presented.

Background values for evaluation of heavy metal contamination in sediments