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Isotopes to Study Nitrogen Pollution and Eutrophication of Rivers and Lakes (F32007)


(Photo: L. Araguas Araguas/IAEA)


CRP at a Glance


The exponential growth of the human population and the rapid co-development of agricultural and industrial sectors in recent decades have caused a sharp increase of nitrogen loading to surface water bodies worldwide. Water quality in thousands of lakes and rivers around the globe is deteriorating due to rising nutrient levels and other chemical pollutants mainly of anthropogenic origin causing changes in their ecological structure and function. The excessive nitrogen pollution (e.g. nitrate, ammonium) of surface waters has resulted in the change of oligotrophic water bodies to eutrophic and sometimes to hypertrophic states. Two of the most commonly recognized symptoms of eutrophication are harmful algal blooms and hypoxia. Moreover, eutrophication has become a serious threat to drinking water quality. Given that consumption of water with high concentrations of nitrate can pose risks to human health, organizations and governmental agencies have established quality standards for water resources and developed regulations and action guidelines for the use of water in the consumption sector.
Nitrogen pollution has been a matter of great concern throughout the world. Isotope techniques constitute a promising tool for determining the sources of nitrogen pollution and eutrophication in surface water bodies and aid in assessing the biogeochemical processes nitrogen undergoes in the aquatic environment and in soils. Overall, environmental isotopes can help in the development of effective management practices and targeted remediation plans to preserve water quality in rivers and lakes.


Nuclear Component


Measurement of 18O and 15N of nitrogen compounds in water samples combined with additional environmental isotopes (e.g., 18O, 2H, 13C of DIC and/ or DOC, 13C, 15N, and 34S of POM) and selected radioactive isotopes of suspended matter (e.g., Sr, Nd, Pb, and Ca).


CRP Overall Objective


To improve expertise and collaboration among Member States in the use of environmental isotopes to better assess nitrogen pollution and eutrophication processes on water resources variability, availability and sustainability.



River water pollution (Photo: I. Matiatos/IAEA)


Water sampling (Photo: L. Araguas Araguas/IAEA)


Isotope Ratio Mass Spectrometer (Photo: L. Araguas Araguas/IAEA)

Specific research objectives

  1. To assess and improve the suite of isotopes and other chemical and/or biological indicators to identify more accurately the multiple sources of nitrogen pollution and eutrophication
  2. To assess and improve the understanding and interpretation of N-nutrient dynamics, eutrophication and sediment transport in lakes and rivers
  3. To explore improved analytical methods of N-related isotope parameters in order to facilitate access to isotope data of nitrogen species and build greater confidence in assessments of nitrogen pollution issues of surface waters
  4. To assess and improve the interpretation of hydrological processes, sources, interactions and pathways in rivers and lakes

Expected research outcomes

  1. More experienced participating Member States in the implementation of environmental isotopes for the assessment of N-pollution and eutrophication in surface waters
  2. Better understanding of possible environmental and anthropogenic impacts of Nitrogen substances on water resources for optimal water resources management and remediation strategies

How to join the CRP?


Please submit your Proposal for Research Contract or Agreement directly to the IAEA’s Research Contracts Administration Section, using the form templates (http://cra.iaea.org/cra/forms.html) on the CRA web site (preferably via email): research.contracts@iaea.org