BLModel boundaries BIOmet tool is a read across tool based on the ‘full BLM’, used for EQS compliance assessment. Number of EU waters fell outside of the pH range. Being outside of the boundaries does not mean: That the relationships were not valid. That the derived generic EQS was not protective for these  waters. But that the uncertainty of the predictions was higher.  Research needed to extend the BLM boundaries. metal pH Ca (mg/L) Zn 6.0-8.0 5.0-160 Ni 6.5-8.7 2.0-88 Cu 6.0-8.5 3.1-93 1

The application range of the Zn-BLM extended IZA Research. University of Ghent. pH effect combined with competitive ion effects.  Refinement and extension of the full zinc BLM. BLM boundaries now validated between pH 5.5 - 8.5.  Most EU waters are now covered. Remaining issue: combination very low DOC, low Ca (e.g. Norwegian mountains . = other ecosystem assembly.  Update (2016) of the BIOMet tool: Arche version 3.04. 2

Biomet extension for pH (FOREGS, 2005) FOREGS River pH Max. 9,80 90P 8,80 50P 7,70 10P 6,40 Ave. 7,49 No. of samples 800 No. of water chemistries outside of the OLD Biomet pH Ca Below pH 6.0 31 Above pH 8.0 220 Below 5 mg/l Ca 159 Above 160 mg/l Ca 32 No. of water chemistries outside of the NEW Biomet pH Ca Below pH 5.5 12 Above pH 8.5 22 Below 5 mg/l Ca 159 Above 160 mg/l Ca 32 3 3