Chapter 9 - Chemical Speciation to Assess Bioavailability, Bioaccessibility and Geochemical Forms of Potentially Toxic Metals (PTMs) in Polluted Soils

Abstract

Potentially toxic metals (PTMs) are persistent contaminants in the soil environment. The simple determination of their total or “pseudototal” content in soil might minimize the risks for biota and human health, assuming that pollutants transferring to water resources or biota are simply correlated with contamination level. In contrast, relevant paradigms in environmental monitoring, risk assessment and remediation feasibility are the PTM mobility, bioavailability and bioaccessibility to microorganisms, plants, animals and humans. For a correct assessment of risk/toxicity (according to PTM content and availability) of a polluted soil and to predict its reduction after application of remediation techniques it is crucial to establish the speciation, mobility, and biogeochemistry of the contaminants. In this sense, a requirement exists for analytical methods and strategies that provide information on the dynamics and behavior of PTMs in soil.