 The potential for SEM-AVS to act as a screening tool in evaluating sediment toxicity due to metals has led several regulatory bodies to use it in the establishment of regulatory assessments of sediment quality.Under the Water Framework Directive, implemented by the European Union in 2003, Environmental Quality Standards (EQS) for metals-contaminated sediments incorporate [SEM]/[AVS] measurements.In sediment quality assessments in Australia, SEM-AVS is employed in second-tier assessment.