Dr. Mitsuru Ebihara Professor, Division of Chemistry, Graduate School of Science and Engineering Tokyo Metropolitan University (TMU)

Neutron activation analysis (NAA) is an analytical method for determining elemental contents. In NAA, neutrons are used to activate samples and gamma rays are measured as signals for most cases. As both neutron and gamma ray are high in penetration capability, even solid samples can be non-destructively analyzed. In addition to such an advantage, multiple elements can be determined with high accuracy for a common and single sample. These features make NAA an outstanding analytical method for elemental determination. As research reactors, the best source of neutrons (especially thermal neutrons) usable for NAA, are running and human resources with NAA are available in participating countries of FNCA, NAA was chosen as a project when FNCA was launched, and has been kept running as a major project up to now.

NAA is widely utilized in many fields such as environmental, biological, medical, geochemical, cosmochemical, material, archaeological and forensic sciences. In the NAA project of FNCA, environmental samples have been chosen as target materials in consideration of demands of participating countries. When the NAA project started in 2000, suspended particulate matter (SPM) as a common material was cooperatively analyzed and data were compared to characterize the air pollution level in FNCA countries. With marine sample being added as target material in 2005, it was especially aimed that the participating countries should take necessary actions to appeal NAA as an effective analytical tool to monitor the environmental pollution level to an appropriate sector of the environmental control authority. Currently, three subprojects are being conducted in parallel; these are NAA of geochemical samples for exploring mineral resources, NAA of food samples for monitoring their safety and NAA of sallow marine samples for monitoring the seashore environment.

In consideration that all participating countries acknowledge the importance of NAA and are supporting the NAA project, I, as a project leader of the NAA project, feel responsible to conduct the project functional and effective, and will do my best to make the FNCA-NAA project more fruitful and expanding in coming future.