In 2016, the IAEA Environment Laboratories hosted, as part of an IAEA technical cooperation project, four fellows from Singapore's National Environment Agency and the Public Utilities Board, Singapore's national water agency. During their three-month stay, the fellows were trained in applying various radioanalytical techniques to measure the activity concentrations of various radionuclides in rainwater, seawater, air, animal and plant samples.
"The hands-on laboratory work allowed me to pick up new skills and good laboratory practices, and all the lectures and exercises trained me to deal with radioanalytical work independently," said Wei Ning Yap, a senior chemist at the Public Utilities Board's Water Quality Office.
They learned in particular how to extract specific radionuclides from large volumes
of seawater by applying a sequential separation method.
After collecting 200litres of seawater and separating out the targeted radionuclides, they performed tests to detect caesium, strontium and plutonium isotopes. The knowledge obtained will help them measure radioactivity levels in Singaporean seawater, seabed and fresh water sediments, and surface water from reservoirs.
"The techniques I learned give me the basis to develop various methods for local application in Singapore," Yap said. "This is very important to safeguard Singapore's water cycle from a radiological perspective."
Tracing marine pollution in Sri Lanka
Scientists at the IAEA Environment Laboratories in Monaco also train fellows in the analysis of carbon and nitrogen stable isotopes in marine samples to investigate pollution and nutrient enrichment. Nuclear and isotopic techniques can be used to trace the source of pollutants in the mixing zones of estuaries and in coastal and shallow waters.These techniques provide a unique source of information on the origins of contaminants and are used to trace their pathways in the environment. They also help scientists reconstruct past environmental conditions, allowing them to track changes in climatic conditions.
Two fellows from Sri Lanka spent two months in the laboratories in Monaco learning about these techniques and instruments. Their training in elemental analyser-isotopic ratio mass spectrometry (EA-IRMS), a technique used to measure the abundance of stable isotopes in different materials, will enable them to use a similar instrument supplied to them by the IAEA upon their return to Sri Lanka.
Scientists at the Sri Lanka Atomic Energy Board are planning to establish an EA-IRMS facility to better develop analytical procedures for stable isotope analysis and to control marine pollution
in the country.
"Identifying sources of contaminants with these precise techniques is crucial, especially in the Negombo lagoon, which provides a direct livelihood for over 5000 families in around 35 villages," said Dulanjalee Rajapaksha, Scientific Officer at Sri Lanka's Atomic Energy Board. "We must continue our work to improve the water quality in our coastal waters."
For more information about the International Conference on the IAEA Technical Cooperation Programme: Sixty Years and Beyond - Contributing to Development, clickhere.