Isotope 'Fingerprinting" is Used to Assess and Secure access to Fresh Water

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Posted on 07 Feb 2013

New CRP on Isotopes in Precipitation and Paleoclimatic Archives in Tropical Areas

A new Coordinated Research Project (CRP) on Stable Isotopes in Precipitation and Paleoclimatic Archives in Tropical Areas to Improve Regional Hydrological and Climatic Impact Models is to be implemented by the IAEA from 2013-2016. CRPs provide an opportunity to work with and learn from colleagues around the world on common isotopic research topics. The final product is an IAEA technical document, and peer reviewed papers or symposia proceedings wherever possible. For more details and application forms, please consult the IAEA website Coordinated Research Activities.

For further information please contact Dagnachew Legesse Belachew.

Posted on 14 Dec 2012

Announcement: 9th IAEA Tritium Intercomparison (TRIC2012)

The Isotope Hydrology Laboratory (IHL) is conducting the 9th International Tritium Intercomparison (TRIC2012) for the performance assessment of tritium (3H) assays in water at low level environmental concentration levels. We invite all laboratories using conventional liquid scintillation and gas proportional decay counting, as well as newer mass-spectrometry-3He accumulation methods to participate. For technical details and to register your laboratory, please visit the TRIC2012 website.

For further information please contact the TRIC team

Posted on 28 Sep 2012

New Software: Laboratory Information Management System for Water Isotope Laser Spectroscopy

The Isotope Hydrology Laboratory (IHL) has partnered with the USGS to develop a Laboratory Information Management System (LIMS) for water oxygen and hydrogen isotopes specifically for users of new laser absorption spectrographs (LIMS for Lasers). Laser spectroscopy has recently revolutionized the analysis of the stable isotopes of water through easy-to-use and robust instrumentation; however the data has not been so easy to work with due to inter-sample memory artefacts, uncontrolled instrumental drift, overwhelming amounts of data, and improper user calibration of results. These problems are overcome by the adoption of LIMS for Lasers, which automates many of these processes, and using systematic approaches has the effect of improving quality assurance, increasing laboratory efficiency, and decreasing laboratory errors. The software is available cost-free from the IAEA - Water Resources Programme and USGS websites.

For further information please contact Len Wassenaar

Posted on 15 May 2012

Isotope Hydrology Laboratory - Final WICO 2011 Report

The final WICO 2011 report is now available for download. The report provides the outcome of a world-wide proficiency test for 137 laboratories conducting routine analysis of δ2H and δ18O in water by isotope-ratio mass spectrometry (IRMS) and laser absorption spectroscopy (LAS). This test revealed that >90 % of laboratory submissions provided acceptable results within ± 2 ‰ for δ2H and ± 0.2 ‰ for δ18O of the established reference values for test waters, and no difference in outcomes based on IRMS vs. LAS technology was found.

However, when including each laboratory's stated precision as an assessment criterion, over 30 % of laboratories had overstated their precision or had very poor precision. The primary cause of outliers appeared to be improper calibration or compromised storage of laboratory standard and primary reference waters, so the importance of proper storage and handling of lab standards cannot be understated. The poor practice of single standard normalization was also identified as a problem for some laboratories. We recommend laboratories strive to report long-term precisions based upon control standards. A synthesis of the WICO report is currently in press in Rapid Communications in Mass Spectrometry.

For further information please contact Leonard Wassenaar.

About Us

Introduction to Isotope Hydrology Section

The Isotope Hydrology Section (IHS) designs and implements the activities of the IAEA's Water Resources Programme, including undertaking various technical activities within the regular budget, such as Coordinated Research Projects (CRPs), publications, isotope data networks (GNIP, GNIR, MIBA) data analysis and technical meetings. Through the Technical Cooperation (TC) programme, technical support is provided to about 65 projects in developing Member States in Africa, Asia, Latin America and Europe. Such technical support includes analytical services, field investigations and data evaluation, workshops and training courses, scientific visits and fellowships, provision of equipment and materials, etc. Building human capacity is a central goal of the Water Resources Programme.

The Isotope Hydrology Laboratory (IHL) is incorporated within the IHS, and aids Member States with analytical support and services, laboratory establishment and upgrading, as well as quality control. The laboratory is equipped with the analytical instruments required to evaluate isotopes in water samples, including a mass spectrometer for tritium-helium measurements.

Joint programmes are also implemented by the Section to develop partnerships — including an IAEA-UNESCO Joint International Isotopes in Hydrology Programme (JIIHP) — and cooperative work is undertaken with other major international and national partners, including the World Bank, Global Environmental Facility (GEF), World Meteorological Organization (WMO), the U.S. Geological Survey (USGS) and the French Research Institute for Development (IRD). Programme achievements and updates can be accessed online in the IAEA´s annual report. The IHS publishes a regular newsletter on the Section´s activities called Water & Environment News about twice a year, providing a detailed description of programme activities, which is also available online at The IHS currently has a team of 20 staff members, including nine laboratory staff, as well as consultants, interns and cost-free experts.

Our Role

Meeting the Challenge

Aspirations for development in many parts of the world are intricately linked to water. Whether concerning issues of health, food and agriculture, sanitation, the environment, industry, or energy production, a paramount issue in the 21st century is water - its availability, quality and management. The IAEA, through its Water Resources Programme, is one of the UN agencies responding to its Member States by providing science-based information and technical skills to improve understanding and management of their water resources.

Solutions through Science

To address global water challenges, such as water shortage and quality, over-exploitation and impacts of climate change on water resources, Member States need precise information to enable them to make decisions about sustainable water resource management. The journey of water from the ocean through the atmosphere, biosphere, to the Earth and back, is commonly known as the hydrological or water cycle.

A comprehensive understanding of this as well as that of hydrological systems such as river basins, lakes, and aquifers is essential to make resource development possible without having an adverse impact on the environment. Determining the 'fingerprints' of water and thereby understanding characteristics such as its source, movement, rate of recharge, pathways etc. is a key aspect of the scientific discipline known as Isotope Hydrology.

Undertstanding the Basics of Water

Atoms of an element with different mass are called isotopes. Water consists of isotopes of hydrogen and oxygen, which are distributed by natural processes throughout all segments of the hydrological cycle. The journey made by each drop of water causes it to undergo small, important and measurable changes in the relative abundance of the different isotopes. Therefore, water in different environments develops characteristic isotopic labels or 'fingerprints' that allow it to be distinctly identified from water in other environments. This make it possible, for example, to trace the source of the water or to estimate how long a body of water has been in the hydrological system.

Tools to Unlock Water's Secret

Nuclear Science has developed an array of methodologies and analytical techniques which use various isotopes of water to characterize water masses and trace their history and movement through the hydrological cycle. The IAEA's Water Resources Programme has been pioneer in developing isotope hydrology as a powerful and effective scientific approach. By tracking the isotopes of water, scientists can quickly obtain valuable information which otherwise may require decades of hydrological data collection.

Isotope techniques can help determine the origin, age and renewal rate of groundwater, and whether it is at risk of salt water intrusions or contamination. It also permits the rapid and reliable mapping of non-renewable groundwater resources, the majority of which are transboundary aquifers, so that they can be abstracted rationally for equitable use. Isotope techniques are important tools to understand surface water movement and inter-action with groundwater, dam leakages, and the impact of climate change on water resources development and management.

Working for Member States

The IAEA works with Member States to adapt and apply isotope techniques to the needs of each country. From technical advice and analysis to capacity building and expert services, the Water Resources Programme is ready to support Member States in addressing their water resource management issues. While helping to test and adapt various techniques under a variety of hydrogeological conditions, the experts from the Water Resources Programme strive to develop the scientific approaches through applied research.

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Responsible/Contact: Isotope Hydrology Section | Last update: 07 February 2013