Development of a method based on activation analysis for total arsenic measurement in brown rice flour (CCQM-K108)

Rice (Oryza sativa) is the staple food for half of the world's populations. Therefore, great attention is done to verify pollutants presence in this food kind. Nowadays, environment is often contaminated with different pollutants produced by industrial processes, agricultural activity with use of pesticides or fertilizers, emission from municipal incinerators and many other sources of pollution. Therefore, different pollutants can contaminate the food for purposes rice. Since, high levels of toxic elements may cause serious damage in human health analytical procedures to check their mass fraction result necessary. In this report we develop an analytical method based on activation analysis for the total arsenic mass fraction measurement in brown rice flour. This material was proposed for a key comparison by the National Metrology Institute of Japan (NMIJ) within the IAWG (Inorganic Analysis Working Group) of the CCQM. The method is checked by measuring arsenic mass fraction of the NIST reference material, SRM 1566b (Oyster tissue). The total arsenic mass fraction determined by neutron activation method results 0.308 mg/kg with associated expanded uncertainty of 6.5% (coverage factor k=2, level of confidence of about 95%)