Soil Contamination by Trace Metals: Geochemical Behaviour as an Element of Risk Assessment

Abstract

Metal pollution in soils, especially agricultural, has become serious problem worldwide, which poses serious threats of entering potentially toxic metals into the food chain. This chapter reviews the concept of trace metals geochemical behaviour in soil and methods of their bioavailability assessment. Special emphasis was given on soil biogeochemical properties, ecological conditions, and plant characteristics that can modify the bioavailable fraction of metals in the soil–plant system. Constraints on the use of different approaches to assess the mobile and bioavailable fraction of trace metals in soil are shown related to the chemical properties of given elements, different soil characteristics and different ecophysiological processes in the rhizosphere. Metal bioavailability is a complex issue that depends on a series of properties appertaining to the soil matrix, plant properties and environmental conditions. An interdisciplinary approach is therefore required to carry out risk assessment studies. The example of using mathematical model and geostatistics in assessment of soil contamination by trace metals is given.