In order to fully test the NER for its potential ecotoxicity, an evaluation of extracted residues will also be performed. Currently there are no standard methods, except for isolation and testing of each transformation product. An approach that tests the whole extract and applies an effect-driven philosophy3 will be developed. In addition, a suitable microbial bioassay will be identified that quantitatively correlates the bio-accessible fraction with the solvent extraction method.
Further guidance in the use of NER data in risk assessment will also be developed. For example, the selection of appropriate test species and how many trophic levels has not yet been defined. Also, relating the exposure concentration to the observed effects in extracts (with uncharacterised transformation products) would need to be considered.
Development of Soup Tests for the Risk assessment of NER in Soil, presented at the 16th Cefic-LRI Annual Workshop 2014