The role of instrumental neutron activation analysis in environmental studies

Instrumental neutron activation analysis (INAA) with its capability for multielement determinations, high sensitivity for many elements, non-destructive and instrumental character has found wide-spread acceptance and usage in environmental studies. INAA is based on a physical principle different from those inherent in other analytical methods and the INAA results are usually less affected by systematic errors. Nevertheless, only a systematic approach to each problem solved together with a proper quality assurance program can ensure a high reliability of the INAA results. INAA is very useful in the pollution studies involving solid samples like atmospheric particulates, coal, stack emission, fly ash, soil, sediments etc. The use of INAA for aqueous and biological samples is less frequent. Some recent developments in the environmental INAA including quality assurance, optimization by means of the information theory, intensive use of computers, interpretation of the results etc.are briefly discussed. INAA is still the method of choice in environmental monitoring and research either in screening studies or especially as a reference method. 53 refs. (author)