Environmental Isotopes in the Hydrological Cycle : Principles and Applications
To support education in isotope hydrology and to enhance the availability of educational and reference materials, the IAEA and UNESCO have co-sponsored development of the series of text books. Available in English and translated in French and Spanish.
Assessing Groundwater Resources in Bangladesh
Exposure to arsenic-contaminated drinking water from shallow aquifers in Bangladesh has resulted in a major public health crisis of recent times. One of the mitigation options is to exploit deep aquifers as an alternative source of safe drinking water. An IAEA-led investigation within its Technical Cooperation framework shows that isotope techniques provide critical hydrogeological information on the sources and movement of groundwater in Bangladesh - information that is necessary for evaluating the causes of arsenic contamination and the long-term consequences of mitigation through use of deeper aquifers.
Inter-Laboratory Comparison for Arsenic Measurement
The IAEA conducted an inter-laboratory comparison involving 17 laboratories in Bangladesh to evaluate the quality of arsenic analysis available in the country. The reported arsenic concentrations in synthetic standards (concentration 0 to ~500 ppb) were found to be highly variable. For field samples, reported results range from 0 to 396 ppb and less than one third of the participating laboratories obtained results that were within about 20% of the expected values (about 60 ppb) obtained by a laboratory cooperating with the IAEA (University of Rochester). The inter-laboratory comparison points to a lack of consistency in analytical results that have been and are being obtained in Bangladesh. More importantly, drinking water wells where elevated arsenic concentrations have been found may in fact have low concentrations. Similarly, wells that have been found to be free of arsenic may in fact have substantially higher arsenic concentrations.

Gridded GNIP Maps and Animations
To facilitate increased use and accessibility of GNIP data and to strengthen and improve cross-disciplinary linkages to the network, a graphical format of the GNIP stable isotope database including global and regional distribution of δ18O,δ2H and d-excess in monthly and annual precipitation, Gridded GNIP maps and animations has been developed.