Human Health Risk Assessment Guidance for Dredging and Disposal At Sea of Marine and Estuarine Sediments
Type:
Presented during:
WODCON XX: "The Art of Dredging" - 2013, Brussels, Belgium
Authors:
Droit J, Bataille T, Delouis A,
Abstract: For sediment dredging or disposal at sea operations, developing an Environmental Impact assessment can be a legal requirement. Human health risk assessment is part of the regulation report.
In order to standardise practices, and to provide port authorities, consultancy companies, and administrations, a common frame of reference, the studies and observation group on dredging and environment (GEODE), decided to produce guidelines.
The purpose of this guide is to adapt the general methodology of health risk assessment to the specific context of dredging and disposal at sea, in compliance with European directives.
As far as chemical risk is concerned, the existing databases (toxicological, physical and chemical) and the methodology for exposure measurement (Technical guidance document, CE 2003) allow to conduct a quantitative risk assessment.
Indicative values of contaminant concentrations within the sediments have been figured for the unique exposure pathway to be considered for these operations: the ingestion of contaminated seafood via the food chain.
Those values provide decision criteria which lead port authorities to assess or not the human health risk.
Scientific publications, interviews of specialists and regulatory reports relative to dredging operations and disposal at sea of several French ports have been analysed in order to define these decision criteria.
Moreover, to confer to these values a protective character, inflating hypotheses have been considered.
As regards the biological risk (bacteria, virus, protozoans, and harmful micro-algae), the absence of database on toxicity factors and the complexity of exposure pathways only enables to implement a qualitative risk assessment.
Keywords: Human health Risk Assessment – harbour sediments – dredging - sea disposal