Economic benefits of methylmercury exposure control in Europe: Monetary value of neurotoxicity prevention

© 2013 Bellanger et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: Due to global mercury pollution and the adverse health effects of prenatal exposure to methylmercury (MeHg), an assessment of the economic benefits of prevented developmental neurotoxicity is necessary for any cost-benefit analysis. Methods: Distributions of hair-Hg concentrations among women of reproductive age were obtained from the DEMOCOPHES project (1,875 subjects in 17 countries) and literature data (6,820 subjects from 8 countries). The exposures were assumed to comply with log-normal distributions. Neurotoxicity effects were estimated from a linear dose-response function with a slope of 0.465 Intelligence Quotient (IQ) point reduction per μg/g increase in the maternal hair-Hg concentration during pregnancy, assuming no deficits below a hair-Hg limit of 0.58 μg/g thought to be safe. A logarithmic IQ response was used in sensitivity analyses. The estimated IQ benefit cost was based on lifetime income, adjusted for purchasing power parity. Results: The hair-mercury concentrations were the highest in Southern Europe and lowest in Eastern Europe. The results suggest that, within the EU, more than 1.8 million children are born every year with MeHg exposures above the limit of 0.58 μg/g, and about 200,000 births exceed a higher limit of 2.5 μg/g proposed by the World Health Organization (WHO). The total annual benefits of exposure prevention within the EU were estimated at more than 600,000 IQ points per year, corresponding to a total economic benefit between €8,000 million and €9,000 million per year. About four-fold higher values were obtained when using the logarithmic response function, while adjustment for productivity resulted in slightly lower total benefits. These calculations do not include the less tangible advantages of protecting brain development against neurotoxicity or any other adverse effects. Conclusions: These estimates document that efforts to combat mercury pollution and to reduce MeHg exposures will have very substantial economic benefits in Europe, mainly in southern countries. Some data may not be entirely representative, some countries were not covered, and anticipated changes in mercury pollution all suggest a need for extended biomonitoring of human MeHg exposure.
Exposure data were contributed from the DEMOCOPHES project (LIFE09 ENV/BE/000410) carried out thanks to joint financing of 50% from the European Commission programme LIFE + along with 50% from each participating country (see the national implementation websites accessible via http://www.eu-hbm.info/democophes/project-partners). Special thanks go to the national implementation teams. The COPHES project that provided the operational and scientific framework was funded by the European Community's Seventh Framework Programme - DG Research (Grant Agreement Number 244237). Additional exposure data were supported by the PHIME project (FOOD-CT-2006-016253) and ArcRisk (GA 226534). We are grateful to Yue Gao and colleagues for sharing Flanders exposure data from the Flemish Center of Expertise on Environment and Health, financed and steered by the Ministry of the Flemish Community. National exposure data from the 2006–2007 French national survey on nutrition and health (Etude Nationale Nutrition Santé) were made available by Nadine Fréry, French Institute for Public Health Surveillance. Data from the Norwegian Mother and Child Cohort Study (a validation sample) were kindly provided by Anne Lise Brantsæter, National Institute of Public Health, Oslo. The UK mercury data were obtained from the ALSPAC pregnancy blood analyses carried out at the Centers for Disease Control and Prevention with funding from NOAA (the US National Oceanographic and Atmospheric Administration). The studies in the Faroe Islands were supported by the US National Institutes of Health (ES009797 and ES012199). The contents of this paper are solely the responsibility of the authors and do not necessarily represent the official views of the funding agencies.