In recent years, environmental concerns regarding antimony have grown considerably due to anthropogenic processes that have
resulted in increasing concentration of Sb in the environment, and also because of its impacts and possible adverse effects
to living organisms. Several techniques have been used, to obtain reliable results for Sb, since Sb is present at low level
concentration, requiring analytical instrumentation with low detection limits. The neutron activation analysis (NAA) technique
has a high metrological level for the determination of several elements in different matrices. However, Sb determination in
environmental and biological samples presents some analytical difficulties due to its low concentrations and gamma ray spectrum
interferences. The objective of this research was to study on Sb determination in environmental reference materials by NAA.
Ten environmental reference materials were selected and analyzed using long period irradiation at IEA-R1 research nuclear
reactor. The induced gamma activities of 122Sb and 124Sb were measured. Relative errors of the results demonstrated that the accuracy depends mainly on Sb radioisotope measured,
the decay time for counting and the sample composition.