ECHA

How to use science for regulatory purposes was one of the key questions tackled at ECHA's first topical scientific workshop, which covered sediment risk assessment. The workshop brought together over 100 experts from around the world to set the scientific principles for assessing risks to the sediment compartment in all regulatory contexts.

"There have been significant developments in science concerning sediment risk assessment, which are not reflected in the current guidance," says ECHA's Jose Tarazona, the workshop Chair. He says that the workshop conclusions provide a good basis for reviewing the current guidance.

"Our aim was to set basic principles that could be applied in all regulatory contexts. After all, the science is the same for predictive risk assessment conducted for example for substances under REACH, and for retrospective site-specific assessments conducted on contaminated areas, for example under the Water Framework Directive. Depending on a specific regulation, the tools and methods may vary, but should be based on shared scientific grounds."

The two-day workshop included general plenary sessions with case studies and topical breakout group sessions, where the participants discussed specific recommendations on how to use scientific knowledge for regulatory purposes.

"There were, for example, recommendations on when to trigger the risk assessment for the sediment compartment, what should be the basic principles and how to use the equilibrium partitioning method* for screening purposes. The participants also gave their ideas for covering the exposure assessment, predicting the concentration levels expected in the environment and reaching the sediment organisms, and elaborated on the tools that are available for describing and predicting the effects," says Dr Tarazona.

Another conclusion from the workshop was that the risks for sediment should be considered as part of the aquatic assessment and should not be restricted to invertebrates. "The current guidance focuses only on sediment invertebrates. Obviously, the invertebrates are very relevant but there are other taxonomic groups and ecological functions that need to be considered as well," Dr Tarazona points out.

This conclusion might mean that simply updating the guidance is not enough - a new conceptual model needs to be developed to make sure that the risks are covered for all relevant substances.

Next steps

The impact of the workshop outcome is quite extensive, according to Jose Tarazona. The workshop proceedings will be published by the end of 2013 on ECHA's website following an extensive consultation with all participants and the workshop international Scientific Committee.

"The proceedings will serve as a basis for reviewing and potentially updating the guidance for REACH and biocides. In addition, participants from the European Food Safety Authority (EFSA), the European Commission and the US Environmental Protection Agency have told us that they will use the workshop outcome for updating their guidance on sediment assessment under the Plant Protection Products Regulation, the Water Framework Directive, and the US sediment assessment framework. The OECD will consider using the workshop outcome and the ECHA guidance update as a starting point for further harmonisation of sediment risk assessment at the OECD level."

The success of the workshop and the valuable network created have already made Dr Tarazona consider a similar event for addressing terrestrial and soil risk assessment.

"That would be a typical follow up because many of the elements for sediment risk assessment are also applicable for terrestrial risk assessment. But we would need to see."

*The equilibrium partitioning method (EqP-method) can be used for adapting the REACH information requirements on soil and sediment testing. To derive screening environmental quality standards for soil or sediment, it uses aquatic toxicity data and a soil/water or sediment/water partitioning coefficient.

Further information

Workshop programme, presentations, list of participants, background material and case studies 

From the participants

Dr Chris Schlekat from the Nickel Producers Environmental Research Association (NiPERA) is one of the scientific committee members, who prepared the outline for the content of the workshop.

"The workshop managed to bring together the right experts to address the very complex issues within regulatory science. Many of the concerns that we have with respect to technical challenges have been discussed and I believe that those discussions can help the nickel industry to incorporate very complicated data into our REACH dossiers," he says.

Dr Schlekat presented to the workshop an approach the nickel industry has taken to solve the technical and scientific challenges for providing generic exposure scenarios for the sediment compartment under REACH. "The appropriateness of the approach we took was discussed in the breakout groups. My initial assessment is that the participants supported most of our decisions."

He thinks that the workshop outcome reflects the state of science from a global perspective. "The workshop proceedings will eventually set the base for developing regulatory guidance for sediment risk assessment."

Another member of the scientific committee, Dr Paul Sibley, Associate Professor at the University of Guelph, congratulates ECHA for an excellent workshop. "It is very good to get experts together to discuss scientific topics. There are advances in different fields and when people network and share ideas, as a result you get a more synergistic perspective that is different from the prevailing sense that exists individually. This will advance the way that science is used in regulatory processes," he says.

Coming from North America, Dr Sibley is interested in seeing how the European regulators are making sure that their decisions are science based. "It is about striking a balance; recognising that science is critical for ensuring sound regulatory policy but at the same time not requiring so much detail that decision making becomes paralyzed."

Dr Sibley is looking forward to contributing to the workshop proceedings. In addition, some of the key issues might be published as scientific papers in peer reviewed publications. "I think that specifically those areas that were identified as knowledge gaps or areas of uncertainty at the workshop, could be flagged in some kind of a summary publication."

Interviews by Hanna-Kaisa Torkkeli