Authors:V. Maihara, P. Moura, M. Catharino, L. Castro, and R. Figueira
Arsenic and cadmium contents in eight edible mushroom species (Agaricus bisporus, Agaricus sp, Pleurotus ostreatus, Pleorotus florida, Pleorotus eryngui, Pleurotus osteatus, Pleurotus salmoneostramineus,
Lentinula edodes) consumed by Brazilian population were determined by instrumental neutron activation analysis (INAA) and graphite furnace
atomic absorption spectrometry (GF AAS), respectively. Arsenic concentrations varied from 0.009 mg/kg in P. eryngui to 0.210 mg/kg dry weight in L. edodoes and Cd from 0.011 g/kg in P. eryngui to 0.229 mg/kg dw in P. salmoneostramineus. The consumption of mushrooms in São Paulo-Brazil may be considered safe from a toxicological point of view as As and Cd
presented levels of ingestion are below the maximum levels recommended by the World Health Organization.
Authors:V. Maihara, I. Gonzaga, V. Silva, D. Fávaro, M. Vasconcellos, and S. Cozzolino
Due to its essential characteristics, the daily dietary selenium intake of individuals should be monitored accurately. In
the current work, daily selenium intake of different Brazilian population groups based on duplicate portion diet analysis
was evaluated and compared with the new estimated average requirement values (EAR), to assess if selenium deficiency or excess
could be observed in these groups. Selenium content was determined by neutron activation analysis (NAA). The average daily
dietary selenium intake found was 26.3 (±8.3) ·g/day for children from the city of São Paulo, 37.4 (±16.0) ·g/day for children
from Belém, 107 (±107) ·g/day for children from Macapá, 28.4 (±7.5) ·g/day for institutionalized elderly, 32 (±6) ·g/day for
non-institutionalized elderly and 37 (±17) ·g/day for university students from São Paulo. Most daily dietary selenium intake
range observed were below the EAR values. The values obtained for children groups from Belém and Macapá cities, whose intake
levels were much higher than the recommendation, were an exception.
Authors:M. Vasconcellos, V. Maihara, D. Favaro, M. Armelin, E. Toro, and R. Ogris
The present paper describes radiochemical separation procedures developed for the determination of the elements As, Cr, Hg, Sb and Se in biological reference materials. The methods chosen utilize ion exchange, retention on inorganic exchangers and solvent extraction techniques for the isolation of the elements of interest. These procedures are more rapid than previously used methods, such as distillation and precipitation. As to the sample dissolution, the following procedures were tested using radioactive tracers and reference materials: treatment of the materials in teflon bombs with a mixture of HNO3+H2SO4 or HNO3 only in a normal oven, and with HNO3 in a microwave oven using specially designed digestion bombs.
Authors:M. Vasconcellos, M. Saiki, D. Fávaro, V. Maihara, A. Figueiredo, and M. Catharino
The Research Reactor Center (CRPQ) of IPEN/CNEN-SP operates the IEA-R1 Research Reactor, at a nominal power of 2 MW thermal,
on a 64 hour per week continuous cycle. The IEA-R1 is a pool type reactor, moderated and cooled by light water, with graphite
as a reflector. One of the main activities of CRPQ is the neutron activation analysis, which is applied to many fields of
research, in collaboration with other institutes and universities. The Research Reactor installations are also intensely used
for human resources development in the field of radiochemistry and neutron activation analysis, at graduate and post-graduate
levels. In the present paper, an overview will be presented of some of the neutron activation analysis research lines that
are being developed, comprising environmental and health-related applications.
Authors:D. Fávaro, V. Maihara, D. Mafra, S. Souza, M. Vasconcellos, M. Cordeiro, and S. Cozzolino
In the present work, the concentration of the 14 elements Br, Ca, Cl, Co, Cs, Fe, K, Mn, Na, Rb, Sc Se and Zn have been determined by INAA in diets of four different groups: (a) 19 pre-school children, (b) 18 healthy adults, (c) 23 elderly people living in private institutions and (d) 19 patients with chronic renal failure (CRF). The contents of proteins, lipids and carbohydrates were also analysed in the diets. The daily intakes of the elements analysed were compared to the recommended values set by RDA or WHO.
Authors:L. A. Farias, D. I. T. Favaro, V. A. Maihara, Vasconcellos M. B. A., L. K. Yuyama, J. P. L. Aguiar, and F. J. Alencar
Daily dietary intake of Hg and some essential elements in diets of children from communities in the Jaú National Park, Amazon
region, were assessed. Diet samples were analyzed for total Hg content using cold vapor atomic absorption spectrometry and
Ca, Fe, K, Na, Se and Zn contents by instrumental neutron activation analysis. The weekly tolerable provisional intake for
Hg in the communities studied varied from 13 to 57 mg of Hg per kg of body weight, exceeding the limit of 5 mg . kg-1 set by the WHO. Comparison of the daily dietary intake values to the new Dietary Reference Intakes (4-8 years), showed prevalence