06 December 2007 Mercury and Lead Pollution: still a Critical Issue in Europe

Human activities release heavy metals into the atmosphere where they are also transported across national boundaries. This results in air, soil and water pollution through the deposition of heavy metals in environments that are located far away from the actual emission sources. Atmospheric deposition of mercury and lead in particular are calculated to be too high, affecting respectively 51.2% and 7.4% of EU-25 ecosystems respectively in 2000. Heavy metals such as cadmium, lead and mercury can result in serious health risks (e.g. lung damage, kidney diseases, nervous system failures, etc.) and can be harmful to the environment (e.g. soil and water pollution, accumulation in plants). In 1979, the European Union (EU) signed the Long-range Transboundary Air Pollution Convention (LRTAP1), which was the first international legally binding instrument dealing with problems of air pollution on a broad regional basis, including pollution due to heavy metals emissions. In Europe, research programs focusing on heavy metals are already in place, including the EU-funded project ESPREME 2, which aims at developing methods and identifying strategies to support EU environmental policy-making for reducing the emissions and thus the harmful impacts of heavy metals. In the framework of the LRTAP, a methodology 3 was developed to assess the critical loads of heavy metals for both terrestrial and aquatic ecosystems, as well as for human health. The critical load is a measure of how much metal input from anthropogenic sources a system can tolerate. It is the threshold below which significant harmful effects on human health and on the environment do not occur, according to present knowledge. Based on this methodology, a team of international researchers calculated the critical loads of cadmium, lead, and mercury in 18 countries of the LRTAP Convention, 14 of them being located in the EU. Some of the indicators used to assess the critical loads include: concentration of heavy metals in ground water, content of heavy metals in grass and animal products (e.g. cows), and concentration of mercury in fish. The authors then estimated the actual levels of atmospheric metal deposition using a long-range atmospheric dispersion model also developed under the LRTAP Convention. These deposition levels were then compared to critical loads, to identify areas where ecosystems were at risk (i.e. where the critical load is exceeded). Results show that: • Cadmium deposition was not a widespread risk in 2000 and caused exceedances with respect to human health particularly in Bulgaria. Added to agricultural inputs (fertilisers), cadmium deposition turn out to cause exceedance of critical loads in agricultural areas, notably in Germany. • The risk to human health posed by lead deposition decreased from 1990 on but was still widespread in 2000: in EU-25, 71.8% of the ecosystem area (e.g. area of land and water investigated) was subject to excess lead deposition in 1990. This was reduced to 8.1% in 2000. • The risk from mercury remained high in 2000: in EU 25, 77.4% of the ecosystem area in 1990 was at risk of ecosystem effects (terrestrial and aquatic) and 51.2% in 2000. The authors propose a critical load approach for evaluation of the need to reduce atmospheric emissions of heavy metals and provide an overview of the risks that deposition of these metals can cause. Revisions of the EU legislation as well as multilateral environmental agreements, such as the LRTAP Convention and the UNEP Mercury Programme 4 could benefit from such results, helping address the major problems with mercury. 1Long-range Transboundary Air Pollution (LRTAP 1) Convention of the United Nations Economic Commission for Europe - http://www.unece.org/env/lrtap/welcome.html 2Project ESPREME “Estimation of willingness-to-pay to reduce the risks of exposure to heavy metals and cost-benefit analysis for reducing heavy metals occurrence in Europe”, (http://espreme.ier.uni-stuttgart.de/) ,under the Sixth Framework Program. 3Manual on methodologies and criteria for modelling and mapping of critical loads and levels and air pollution effects, risks, and trends. UBA-Text S2/2004, Berlin, Germany: Federal Environmental Agency, http://www.icpmapping.org 4UNEP Mercury Programme - http://www.chem.unep.ch/MERCURY/ Source: J. Slootweg et al. (2007) “European Critical Loads of Cadmium, Lead and Mercury and their Exceedances”, Water Air Soil Pollution: Focus Vol 7: 371- 377 Contact: [email protected] Theme(s): Chemicals, air pollution Opinions expressed in this News Alert do not necessarily reflect those of the European Commission To cite this article/service: "Science for Environment policy" : European Commission DG Environment News Alert Service, edited by BIO Intelligence Service. European Commission DG ENV 1 News Alert issue 89

December 2007