Page 179 - 00. Complete Version - Progress Report IPEN 2014-2016

Nuclear Science and Technology | Progress Report 179

Fig 23. Bottles of the bovine kidney reference material.

All the steps for the production of a bovine similar matrix showed that the mussel candi-
kidney reference material were developed, date reference material presents particle size
including sampling, sample pretreatments, distribution similar to the IAEA-407 fish ho-
freeze-drying, grinding, sieving, homogeni- mogenate, prepared with similar technique.
zation and gamma ray sterilization. Physical (Partnership: CQMA – IPEN; Funding: IAEA,
and chemical characterization following in- FAPESP, CNPq, CNEN, CAPES).
ternationally agreed recommendations were
performed, with emphasis on the assessment
of the stability of the material, its homogene-
ity status, residual water content and granu-
lometric characterization. An international
interlaboratory program was performed for as-
signment of As, Cd, Cu, Cl, Co, Cr, Fe, Hg, K, Mg,
Mn, Na, Pb, Se and Zn values and associated
expanded uncertainties for the kidney tissue.
Fig 24. Particle size distribution for various reference materials.
In the case of the previously prepared mus-
sel reference material, its particle size distri-
bution was characterized by Laser Diffraction NAA studies in Crassostrea oyster shells
Particle Analysis and compared with other ref-
erence materials as the distribution may in- In this study, the neutron activation is used in
terfere with the homogeneity properties of the Crassostrea genus oyster shells to verify
the material. It was observed that the mussel the feasibility of using trace elements as pa-
candidate reference material presents mean leo-environmental markers. Samples of oys-
particle size of 94.6 ± 0.8 μm, with Gaussian ter shells were collected covering the South,
distribution. The comparison with the results Southeast and Northeast regions of Brazil.
obtained for certified reference materials with To determine the crystalline structure of the