Fractionation of rare earth and other trace elements in crabs, Ucides cordatus, from a subtropical mangrove affected by fertilizer industry.

Fractionation of rare earth elements (REE) and other trace metal concentrations (Th, U, Cd, Cr, Cu, Ni, Pb, and Zn) between mangrove sediments and claw muscles and shells of male crabs (Ucides cordatus) from a subtropical estuary highly impacted by fertilizer industry activities was investigated. This is the first record of REE distribution in these organisms, and the results showed higher accumulations of these metals, U and Th in shells, probably related to the replacement of Ca during molting. Contents of Cd, Cr and Ni were similar in both tissues, but Cu, Zn and Pb were mostly accumulated in the claw muscle with concentrations above those considered safe for human consumption according to the Brazilian legislation. REE fractionation was different in the analyzed tissues being softer in the shells. The results provided evidences that the water absorbed during molting controls the chemistry of REE in shells. In contrast, the chemistry of REE in the claw muscle, in which was observed preferential absorption of light REE, is controlled by diet. REE fractionation obtained for the claw muscles was closely correlated to the observed in the contaminated substrate and in materials related to the production of phosphate fertilizers (contamination source), which supports their transference to this Ucides cordatus tissue without fractionation by the ingestion of sediments. Our results showed the potential use of crab tissues for monitoring REE and trace element sources in mangrove areas, with claw muscle exhibiting the contaminant source fingerprint.

Macro and trace elements in edible mushrooms, Shiitake, Shimeji and Cardoncello from Petrópolis, Rio de Janeiro, Brazil / Macro e elementos-traço em cogumelos comestíveis, Shiitake, Shimeji e Cardoncello, coletados em Petrópolis, Rio de Janeiro, Brasil

The concentrations of twenty-five elements (Al, As, Ba, Bi, Ca, Cd, Cr, Cu, Fe, Ga, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Rb , Sb, Se, Sn, Sr, V and Zn) were determined in three edible mushrooms, Shiitake (Lentinula edodes), Black Shimeji (Pleurotus ostreatusi) and Cardoncello (Pleurotus eryngyii) from Petrópolis, Rio de Janeiro, Brazil. Samples were collected along the year 2010 and their preparations were made after drying, milling, an acid pre-digestion and a decomposition procedure in a muffle furnace. The analytical techniques employed for the elements determination were Mass Spectrometry with Inductively Coupled Plasma and Flame Atomic Absorption Spectrometry. Two certified reference materials, Apple Leaves and Mussel Tissue, were used for the evaluation of the analytical procedure and recovery values around 98% were obtained. The results showed that the analyzed mushrooms have high levels of Cu, Fe, K, Mg, Mn and Zn containing more than 30% the recommended daily intake for these nutrients according to Brazilian legislation. These mushrooms presented a very low ratio Na/K. Regarding the levels of some contaminants, the mushrooms had concentrations of Cd, Pb and As below the recommended maximum limits allowed by Brazilian legislation.

As concentrações de vinte e cinco elementos (Al, As, Ba, Bi, Ca, Cd, Cr, Cu, Fe, Ga, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Sn, Sr, V e Zn) foram determinadas em três cogumelos comestíveis, Lentinula edodes (Shiitake), Pleurotus ostreatusi (Shimeji preto) e Pleurotus eryngii (Cardoncello) provenientes de Petrópolis, Rio de Janeiro, Brasil. As amostras foram coletadas durante o ano de 2010 e o preparo efetuado por secagem, trituração, pré-digestão ácida e mineralização em mufla. As técnicas analíticas utilizadas na determinação dos elementos foram a espectrometria de massa com plasma indutivamente acoplado e a absorção atômica com chama. Dois materiais de referência certificados, Apple Leaves e Mussel Tissue, foram utilizados para a avaliação do procedimento analítico e valores de recuperação em torno de 98 % foram obtidos. Os resultados demonstraram que os cogumelos estudados apresentam altos teores de Cu, Fe, K, Mg, Mn e Zn, contendo mais de 30% das quantidades recomendadas para ingestão diária desses nutrientes, conforme a legislação brasileira. Esses cogumelos possuem uma razão Na/K muito baixa e os níveis de alguns contaminantes, Cd, Pb e As, estão abaixo dos limites máximos permitidos pela legislação em vigor.