The derivation and use of soil screening values for 

metals for the ecological risk assessment of 

contaminated land: a regulatory perspective

Abstract

Naturally occurring elements, which in some cases may be biologically essential but also potentially 

toxic, present significant problems to those charged with characterising and assessing ecological 

risk. The Environment Agency and Defra have developed a tiered ecological risk assessment

frame

work for contaminated land, which has at Tier One, soil screening values for comparison with meas

ured field concentrations. For the soil screening values for metals to be ecologically relevant and 

effectively reflect potential risk, they must balance essentiality with potential toxicity. In addition, they 

must consider variations in ambient background concentrations, the use of ecotoxicological data 

developed in the laboratory – not in the field, and the influence of soil physico-chemical properties on 

metal availability.

Through the assessment of chemicals under the Existing Substances Regulations (Directive 98/8/

EC) programme at a European level, in particular for Zn, and the Voluntary Risk Assessments for Cu 

and Pb, research tools and techniques have been developed to address the environmental 

rele

vance of total measured soil metal concentrations. The focus of this paper is upon the application 

and synthesis of the latest thinking from this metals research arena in a manner that attempts to 

meet both regulatory and stakeholder needs for soil screening values for ecological risk assessment.

Key words: metals, risk assessment, soil screening

© 2007 EPP Publications Ltd

To purchase the full article as a pdf (price £19.00), please click on 'buy now'. Payment can be made by PayPal or credit card for immediate download.

Article code 794