1. The extent to which a satisfactory basis exists for the application of an effects- based approach for Pb, Cd, Hg Report of the Working Group on Effects H.-D Gregor

2. Main advantages of the critical load approach in the framework of the CLRTAP: CL can be directly compared to deposition rates (but also other input rates) CL aim at avoidance of any harmful effect to human health and the environment in the long-term perspective (= "sustainability") CL are derived for receptor areas considering their specific sensitivity against metal inputs. CL maps can be produced. There are different effects-based approaches, one of them is the critical load approach.

3. End of 1980s: Because of rising concern about possible harmful accumulation of metals in the environment due to LRTAP the idea arose to adapt the CL approach for application for heavy metals The critical load approach has been successfully applied for policies to reduce acidification and eutrophication. 1994: 2. Sulfur Protocol 27 Parties 15 countries delivered national CL data 1999:Gothenburg Protocol 20 Parties 24 countries delivered national CL data

4. CL(M) History: 1989: Sweden WS 1994: ESQUAD Study published 1996: First draft Manuals published (NL) 1997: Workshop Bad Harzburg 1998: Revised Manuals 1999: Workshop Schwerin 2000: Ad-hoc Expert Group on critical limits, Bratislava 2001: Mapping guidance 2001: Expert Panel on HM established 2001/2: voluntary call for CL(M) data 2002: Berlin WS 2003: Expert Panel meeting 2004: WS Potsdam 2004: HM chapter of the M&M Manual 2004: call for data 2006: Expert Panel meeting CL(M) updates A CL(M) approach was developed in a 16 years process (1990 - 2006) of discussion and sophistication. The Arhus Protocol on HM (1998), Article 6g encourages its Parties to develop an effects-based approach...

5. The Arhus Protocol on HM (1998), Article 6g "... which integrates appropriate information... on modelled or measured environmental levels, pathways, and effects on human health and the environment, for the purpose of formulating future optimised control strategies..."

6. LRTAP contributes a considerable portion of the load. Cd accumulation in agricultural soils, P supplied with "low-Cd" fertilizer (TF Health 2006 update - draft) + 0.03 %+ 0.05 % Metals further accumulate in agricultural and forest soils and in whole catchments,

7. Human health pathways and effects: Air - soil - groundwater - drinking water (Pb, Cd, Hg - WHO 2004) Air - soil - food (Cd - De Vries et al. 2005) Air - precipitation - catchment - fish(Hg - WHO/FAO 2003) Ecotoxicological pathways and effects: Air - soil - plants, invertebrates, microbiota Pb, Cd: critical limit function for free metal ions (Lofts et al. 2003) Hg: critical limits related to the Hg concentration in soil organic matter (Meili et al. 2003) The current CL methodology:

8. Laboratory experiments and field tests (Hg) on effects on plants, microbiota Some selected results: Ecotoxicological effects:

9. Human health effects (Results from EB.AIR/WG.1/2006/12): Hg effects: neurotoxic effects, unborn children are most susceptible group, exposed mainly due to fish consumption of the mother. In some populations consuming large amounts of fish, or contaminated fish, harzardous levels may be reached. Decreasing the Hg concentration in fish should be treated as a high priority. Pb effects: impairment of neurodevelopment in children - even at blood concentrations below 100 µg/l There may be no threshold for the effects. In the long term the rise of lead levels in soils is a matter of concern and should be avoided. Cd effects: increased protein excretion as result of tubular cell damage, increased risk of osteoporosis Safety margin between present daily intake and effects thresholds small or not existing (sensitive parts of population) effects presently possible! effects presently possible!

10. The CL(M) methodology takes the most recently available state of knowledge into account. Expert Panel on Heavy Metals (under ICP M&M), January 2006 (Minutes) 3 a) The Expert Panel supports the practice to start effects-based approaches for HM by calculating critical loads and their exceedances and to use the results in policy. Dynamic models are more complex and should be used as a complement. The 24 WGE (2005), later confirmed by EB.AIR/WG.1/2005/87, No 19 (g): 44. (d) Took note of ICP Modelling and Mapping analyses of critical loads of heavy metals (EB.AIR/WG.1/2005/10/Add.1) and recommended that the results be used in work under the Convention. The 23 WGE (2004), later confirmed by EB.AIR/WG.1/2005/83, No 20 (i): 33. (c) Took note of the recent developments and the report of the ICP M&M workshop on critical loads of heavy metals (EB.AIR/WG.1/2004/10/ Add.1) concluding that effects-based approaches for heavy metals were sound and recommending the results for use in work under the Convention. Potsdam 2004 (Minutes): 10. During the discussion it was stressed that uncertainties in input data or parts of the models do not question the scientific soundness and applicability of the critical loads approach for heavy metals as a whole.

11. The CL(M) methodology is applicable (at least) in the entire EMEP domain CL maps for whole Europe can be produced based on a background database (forests) for Europe 2004/2006 18 countries delivered data for critical loads (Pb, Cd, Hg) or critical Hg concentrations in precipitation, respectively Cd Pb Hg

12. Uncertainties in Exceedance calculations are mainly due to uncertainties in emission data. Taking this into account and the fact that IAM are not available for HM, performing scenario analyses would be a reasonable option for the use of CL(M) data, see ECE.EB.AIR/WG.5/2006/2, No 75.

13. The 25 WGE (2006), paragraph 41.: (c) took note of ICP Modelling and Mapping's new critical loads for heavy metals (EB.AIR/WG.1/2006/10) and recommended that the results be used in work under the Convention (d) Approved the update of critical loads on heavy metals (EB.AIR/ WG.1/2006/10); confirmed again the underlying methodology was scientifically sound and formed a satisfactory basis for the application of an effects-based approach as described in EB.AIR/WG.5/2006/2 para 75. It noted that uncertainties in critical loads exceedance calculations were mainly found in emissions data. It recommended that the results be used in work under the Convention, in particular in the review of the Protocol on Heavy Metals and entrusted its Chairman to include these conclusions in his report to the thirty eight session of the WGSR.

14. Pb Hg Thank you! Cd Hg Pb Thank You!

15. Results from the Working Group on Effects: Recent/current ICP activities concerning heavy metals: ICP Forests, HM in Forest soils (eg For.Cond.Rep.) Pb, Cd, Zn, Cu, Fe, Cr, Ni, Mn ICP Waters, Heavy Metals in Surface WatersPb, Cd, Zn, others ICP Vegetation/ Pb, Cd, Cu, As, Cr,Ni/ Moss Survey deposition to mosses ICP IM, Pools and Fluxes Pb, Cd, Cu, As, Cr,Ni, Zn, V TFH, Health Risks of HM from LRTAP Pb, Cd, Hg ICP M&M +EMEP MSC-E, First preliminary maps Pb, Cd ICP Materials 2003, Release of HM due to corrosion (source !!) Zn, Cu 22WGE report to HM workshop Langen 17-18 November 2003