Brazil nuts: determination of natural elements and aflatoxin
Castanha do Brasil: determinação de elementos naturais e aflatoxinas
Acta amaz; 42 (1), 2012
Publication year: 2012
A study was carried out to evaluate the association of levels of radioactivity, selenium and aflatoxin in shelled Brazil nuts, which were classified in different sizes, for export. The selenium determinations were performed by inductively coupled plasma optical emission spectrometry (LOQ = 3.0 µg g-1), and aflatoxins were detected by Liquid chromatography-mass spectrometry (LOQ = 0.85 µg kg-1), recovery rates were between 92 and 100 percent. Radioactivity was measured by high-resolution gamma spectrometry. The selenium mean concentration was (22.7 ± 7.4) µg g-1. (n = 30).
Mean activities determined for the following radium isotopes were:
15.77 Bq kg-1 for 224Ra, 104.8 Bq kg-1 for 226Ra and 99.48 Bq kg-1 for 228Ra. For 226Ra, the levels did not vary significantly with nut sizes, although such differences were observed for 224Ra and 228Ra. There was no statistically significant association between the level of selenium and the activity of radionuclides, however, there was correlation between the radionuclides. Aflatoxins above the quantification limit were not found.
Um estudo foi realizado para avaliar a associação dos níveis de radioatividade, selênio e aflatoxinas em castanha-do-Brasil descascada, que foram classificadas em diferentes tamanhos, para exportação. As determinações de selênio foram realizadas por espectrometria de emissão óptica com plasma indutivamente acoplado (LOQ=3,0 µg kg-1) e aflatoxinas foram detectadas por LC-MSMS (LOQ=0,85 µg kg-1), as taxas de recuperação ficaram entre 92 e 100 por cento. A radioatividade foi medida por espectrometria gama de alta resolução. A concentração média de selênio foi de (22,7 ± 7,4) µg g-1. (n = 30).