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Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg −1 ) and porridge (254 μg kg −1 ), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg −1 (porridge), 16 μg kg −1 (flour), and 188 μg kg −1 (bread), respectively. Total As concentration in Brazilian rice-based baby food was −1 . However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d −1 , respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.

This review is focused on the impurities determination in uranium nuclear fuel grade matrix with the use of spectrometric methods. It is known that uranium is the major element and material for the sustainable use in the nuclear energy. The optimized use of this technology involves the improvement of several processes to power generation. With regard of fuel reliability, the chemical characterization combined with environmental protection is particularly important in the uranium production cycle or in the nuclear fuel cycle, subject to an increasing number of international conventions and protocols. The performance of nuclear fuel in reactors depends mainly on the chemical composition of its impurities and its estimation is important from the point of view of neutron economy. Among the instrumental analytical techniques commonly used for the determination of elemental impurities in uranium compounds spectrometric techniques are commonly used, such as; FAAS, GFAAS, ICP OES and ICP-MS. Usually, it is necessary in a previous uranium separation and preconcentration of the impurities for elemental determination. Thus, the aim of this review is to give an overview of the main process using sample preparation, separation and preconcentration of analytes for the instrumental determination.

The concentrations of vapor phase polycyclic aromatic hydrocarbons (PAHs) were measured at the Central Bus Station of Londrina, where only diesel-powered vehicles circulate. The samples were collected within a period of 24 h for 14 consecutive days in January 2002. The semi-volatile PAHs were collected using a cartridge packed with XAD-2 resin, extracted under sonication and subsequently analyzed by gas chromatograph equipped with the flame ionization and mass spectrometer detectors (GC-FID and GC/MS). Ten PAH compounds were found (naphthalene, acenapthylene, acenapthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene and chrysene). The average concentrations ranged from 1.4±0.3 ng m −3 for benzo(a)anthracene to 348.0±32.7 ng m −3 for phenanthrene. The species that presented higher concentration were phenanthrene (348.0±32.7 ng m −3 ), fluorene (140.2±17.3 ng m −3 ) and naphthalene (97.7±10.3 ng m −3 ). The PAHs with two and three rings were responsible by 90.2% of the total concentration among 10 PAHs. The concentrations of PAHs were lower on Sunday in comparison with the workdays, due to the reduction of bus traffic in the station. Correlations and principal component analysis with Varimax rotation were used to estimate the local PAH emission source profile originating from the diesel exhaust. The ratio PHEN/FLU of 2.5 calculated from the results is suggested as indication from diesel combustion exhaust.