Neutron activation analysis of antimony in soils: a comparison of NAA with digestion/ICP-MS methods and ‘consensus’ laboratory data

摘要

The analysis of antimony in soil is an important component in the assessment of environmental risk associated with the discharge of munitions at small arms ranges. Proficiency testing samples associated with accreditation to the ISO 17025 standard have been examined for their antimony content using Instrument Neutron Activation Analysis (INAA) and using microwave assisted in situ hydrofluoric acid or nitric acid digestion, or nitrate ashing, followed by ICP-MS analysis. Data are compared with the proficiency testing criteria associated with accreditation and with consensus data. All three techniques afford data which are consistent with accredited analyses. However, the antimony concentrations obtained are method dependant, and generally as follows; INAA in situ HF nitrate ashing nitric acid. In situ HF data and nitrate ashing data are systematically higher and lower than consensus values, respectively, but within the acceptable accreditation range. INAA is the only technique which affords a concentration for antimony in the certified reference material PACS-2 (10.0 ± 0.1 μg g−1) which is not statistically different from its certified value (11.3 ± 1.3 μg g−1).