Chemical and ecotoxicological guidelines for managing disposal of dredged material

Abstract Different conventions around the world have produced guidelines for the disposal of dredged material (e.g., London Convention 1972 (LC) ( www.Londonconvention.org ); Oslo/Paris Convention (OSPAR) ( www.ospar.org ); and, the Helsinki and Barcelona Conventions). They suggest the use of different methodologies from physico-chemical to biological approaches to the management of different routes of disposal or uses of the dredged material. Most of these conventions propose methods based on a `weight of evidence' (WOE) approach. It consists from the beginning of a simple screening approach and progresses to more detailed assessments in cases where any initial management concerns cannot be discounted. Initial assessment considers factors relating to the dredged material, such as the particle-size characteristics of the dredged material, local and historic information, and its environment (e.g., surrounding industries, pollution sources, and collectors). If this information is insufficient to provide answers for the management proposed for it, then further data must be collected that involves chemical characterization of the dredged material. In some countries, these primary assessment processes also incorporate biological screening tests. If management decisions regarding sediment quality cannot be made from initial and primary assessments, direct measurements of toxicity and/or bio-accumulation and/or other case-specific studies may be required, until it is judged that sufficient information is available for a decision to be made about the disposal or use of the dredged material. We aim to review the different methodologies used for characterizing dredged material with an special focus on Spain, describing recent initiatives that include revision of some of the most common tests used to assess sediment quality and potential guidelines for the management of the disposal of dredged material.