Estimation of incidence and social cost of colon cancer due to nitrate in drinking water in the EU: a tentative cost-benefit assessment

<p>Abstract</p> <p>Background</p> <p>Presently, health costs associated with nitrate in drinking water are uncertain and not quantified. This limits proper evaluation of current policies and measures for solving or preventing nitrate pollution of drinking water resources. The cost for society associated with nitrate is also relevant for integrated assessment of EU nitrogen policies taking a perspective of welfare optimization. The overarching question is at which nitrogen mitigation level the social cost of measures, including their consequence for availability of food and energy, matches the social benefit of these measures for human health and biodiversity.</p> <p>Methods</p> <p>Epidemiological studies suggest colon cancer to be possibly associated with nitrate in drinking water. In this study risk increase for colon cancer is based on a case-control study for Iowa, which is extrapolated to assess the social cost for 11 EU member states by using data on cancer incidence, nitrogen leaching and drinking water supply in the EU. Health costs are provisionally compared with nitrate mitigation costs and social benefits of fertilizer use.</p> <p>Results</p> <p>For above median meat consumption the risk of colon cancer doubles when exposed to drinking water exceeding 25 mg/L of nitrate (NO₃) for more than ten years. We estimate the associated increase of incidence of colon cancer from nitrate contamination of groundwater based drinking water in EU11 at 3%. This corresponds to a population-averaged health loss of 2.9 euro per capita or 0.7 euro per kg of nitrate-N leaching from fertilizer.</p> <p>Conclusions</p> <p>Our cost estimates indicate that current measures to prevent exceedance of 50 mg/L NO₃are probably beneficial for society and that a stricter nitrate limit and additional measures may be justified. The present assessment of social cost is uncertain because it considers only one type of cancer, it is based on one epidemiological study in Iowa, and involves various assumptions regarding exposure. Our results highlight the need for improved epidemiological studies.</p

Global challenges for nitrogen science-policy interactions : Towards the international nitrogen management system (INMS) and improved coordination between multi-lateral environmental agreements

Human interference with the nitrogen cycle has doubled reactive nitrogen inputs to the global biosphere over the past century, leading to changes across multiple environmental issues that require urgent action. Nitrogen fertilizers and biological nitrogen fixation have allowed benefits of increased crop harvest and livestock production, while in some areas there is insufficient nitrogen to fertilize crops. Whether in excess or deficit, nitrogen losses from its inefficient use are causing a combination of freshwater and marine pollution, air pollution, alteration of climate balance, stratospheric ozone loss, biodiversity loss and reduction of soil quality. The resulting nitrogen pollution affects human health, well-being and livelihoods. Scientific efforts have begun to bring these issues together. However, there is still a high degree of fragmentation between research on the different benefits and threats of reactive nitrogen and between the respective policy frameworks, especially at the global scale. We argue that a more joined-up approach to managing the global nitrogen cycle is needed to develop the 'gravity of common cause' between nitrogen issues and to avoid policy trade-offs. We describe how a coherent system for science evidence provision is being developed to support policy development through the 'International Nitrogen Management System' (INMS). There is now a matching challenge to bring together the multiple policy agreements relevant for nitrogen as a foundation to address synergies/trade-offs and to set priorities. Based on review of existing frameworks, we outline the concept for an Interconvention nitrogen coordination mechanism. This could make a major contribution to multiple Sustainable Development Goals by stimulating the next generation of international nitrogen strategies: maximizing the benefits of efficient nitrogen use, while minimizing its many environmental threats

Just enough nitrogen: Summary and synthesis of outcomes

Food production and power generation have increased to feed growing populations and to keep pace with economic development, leading to major human alteration of the global nitrogen (N) cycle. The result is a global challenge, with many regions having ‘too much’ or ‘too little’ nitrogen. As di-nitrogen (N2) in the atmosphere, nitrogen is one of the most abundant elements, but which cannot be used by most organisms. Conversely, reactive nitrogen (Nr) is essential for organisms, but is mostly in short supply for natural ecosystems. Human activities have polarized the differences in Nr flows between different world regions, leading to major sustainability challenges, with implications for food security, adverse impacts on health and ecosystems, and the need to develop tools and policies for better management. In developed regions, abundant use of manufactured fertilizers, crop biological nitrogen fixation and inadvertent formation of nitrogen oxides via combustion processes are leading to a plethora of environmental problems. These threaten air quality, water quality, soil quality, greenhouse gas balance, stratospheric ozone levels, biodiversity and human health. At the same time, in many developing regions, insufficient access to reactive nitrogen is leading to degradation of agricultural soils including N depletion, making it vital to reduce losses and recycle available nitrogen stocks. Nitrogen emissions as a result of agricultural practices and combustion for energy represent a major economic loss. Adding up all N losses in the world (excluding emissions from oceans) amounts to a lost agricultural fertilizer resource worth around $200 billion USD annually. The societal costs to human health, ecosystems and climate are even larger at$400–4000 billion USD annually. Knowledge of these figures can help motivate society to optimize with ‘just enough’ nitrogen. This chapter provides an overview of results from the 6th International Nitrogen Conference, Kampala (Uganda), which considered the question of how to optimize practices for ‘just enough’ nitrogen both internationally and specifically for the African Continent. From experimental trials to scenario analysis, the contributions demonstrate the approaches being used. The messages in very different regions often turn out to be surprisingly similar. They encompass all aspects of society: optimizing the use of available fertilizer and manure resources (both under excess and under scarcity conditions), improving nitrogen use efficiency, developing landscape integration, and optimizing our food choices by prior planning that can also reduce food waste. Together, such nitrogen-related strategies will have major benefits for global environmental sustainability

The INI European regional nitrogen centre : Concepts and vision

In the global setting of the International Nitrogen Initiative (INI), the European Centre facilitates enhanced cooperation and integration among European researchers, policy makers and practitioners on environmental issues related to reactive nitrogen. INI-Europe represents a region that is characterized by agronomic challenges posed by high population density and the associated large food demand, but a declining economic share of agriculture. It is largely an area of excess nitrogen, a fact that is increasingly being recognized by stakeholders and environmental policy. INI-Europe aims to promote awareness building and to provide scientific information to stakeholders and the policy process, in order to facilitate implementation of measures to reduce environmental nitrogen loads and associated impacts