Pollution of sediments

Contamination of sediments by toxic substances

Nature

Many metals and organic substances have an affinity for organic matter or mineral particles. Sediments thus provide a suitable medium for the accumulation of contaminants from aqueous sources and atmospheric deposition. The contaminant level is often higher than in the overlying body of water.

Counter-claim

Certain elements, often associated with pollution, tend to occur naturally in sediments and their concentrations reflect the geology of the areas (as in the case of lake basin).