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Nuclear Science and Technology | Progress Report 177
wine are important for: organoleptic features Contribution to food safety assurance
that consequently affect the sensor quality, of fish consumed at São Paulo city
including flavor, freshness, aroma, color, taste
and so on. The trace elements are also good Controlling seafood quality is essential to en-
indicators of the origin of the wine, due to its sure its safety for human consumption. Howev-
direct relationship with soil composition and er, scarce information is available about seafood
their concentrations can be used as criteria contaminant status in complex metropolitan
to ensure authenticity. There are virtually markets in Latin America. By the Brazilian law
no studies that apply Instrumental Neutron enforcement, the presence of toxic elements
Activation Analyses (INAA) specifically in such as As, Cd, Hg, Pb, Se and Zn in fish must be
wines. Among its advantages, the analysis monitored and be below stated values prior to
does not require large amounts or chemical human consumption. But little is known about
treatment of the samples and the ability to the actual dietary fish intake in Brazil as it may
determine various elements with high sensi- be a regionalized issue. Toxic and essential el-
tivity. In this study, the concentrations of Cl, K, ements were determined in some of the most
Mg, Mn, Na and V in seven Brazilian red wine consumed fish species in São Paulo city, Brazil:
freeze-dried samples from Rio Grande do Sul whitemouth croaker (Micropogonias furnieri),
were determined by Instrumental Neutron smooth weakfish (Cynoscion leiarchus), com-
Activation Analysis (INAA). mon snook (Centropomus undecimalis) and
Brazilian sardine (Sardinella brasiliensis). These
Determination of essential and fish species are locally known in Portuguese as
toxic elements in marine algae by “corvina”, “pescada” “robalo”, and “sardinha”,
Neutron Activation Analysis respectively. INAA was applied for the deter-
mination of As, Br, Co, Cs, Fe, K, Na, Rb, Se and
Overtime, seaweeds have been used as food Zn while Cd, Pb and Hg were determined by
mainly due to their high nutritional value. Atomic Absorption Spectrometry. Centropomus
This type of food is considered as functional undecimalis was the only species to present
food and contributes to the nutritional hu- element mass fractions under the limits of
man requirements, being beneficial to hu- national and international legislations for all
man health. In this study, 13 edible seaweed elements, with the exception of As results that
samples, acquired in the marked of São Paulo surpassed the Codex Alimentarius limits. Re-
city, were analyzed and the concentrations sults for As for all the other species were above
of elements As, Br, Ca, K, Fe, Mg, Mn and Na those permitted by the Brazilian legislation.
were determined by Instrumental Neutron Nevertheless, it cannot be affirmed that these
Activation Analysis (INAA). Cu, Cd and Pb will species are toxic for humans and should be
be determined by Graphite Furnace Atomic avoided as most of the As in fish is in the or-
Absorption Spectrometry (GF AAS). The fol- ganic form arsenobetaine that is assumed to
lowing edible seaweeds were analyzed: Nori be of no toxicological concern.
(Porphyra umbilicates); Hijiki (Hijikia fusi-
forme); Kombu (Laminaria sp.) and Wakame Activity levels of gamma-emitters and
(Undaria pinnatifida) species from China, barium concentrations in Brazil nuts
USA, Japan and South Korea. Hijiki specie
showed to be source of Ca and Fe while Kombu In recent years, nutritionists have suggested
specie for K. daily intake of a certain portion of Brazil nuts
