In 2008 ECETOC held a workshop on Probabilistic Approaches for Marine Hazard Assessment (ECETOC, 2008) which included discussion of the application of ETX-type SSDs for marine hazard assessment. The outcome identified key statistical and ecological challenges and further research to address them. Since then refined regulatory guidance has helped applicability of SSDs in risk assessment but there remain ecological and statistical challenges. Other approaches to SSDs have emerged over this period, e.g. US EPA Web-ICE and a prototype hierarchical model from Durham University, UK, both of which utilise prior knowledge of interspecies sensitivity relationships in deriving HC5 values.
These developments suggested that a workshop bringing together SSD practitioners from industry, regulatory agencies and academia would be valuable in discussing and report current thinking on when and how SSDs, should be used and how the methodology might be further developed. With this in mind, ECETOC organised this latest workshop with the aim of addressing 3 key aspects:
- What is the ecological relevance of an SSD?
- What SSD statistical models are available for deriving toxic thresholds (HC5/PNEC) for aquatic communities?
- Regulatory application