Edevaldo da Silva

Distribution of trace elements in tissues of shrimp species Litopenaeus vannamei (Boone, 1931) from Bahia, Brazil

In this study, concentrations of trace elements in tissues of shrimp species (Litopenaeus vannamei) from farming and zone natural coastal located in the northeastern Brazil were investigated. The elements determination was performed by optical emission spectrometry with inductively coupled plasma (ICP OES). The following ranges of concentrations in the tissues were obtained in µg g-1 dry weight: Al: 13.4-886.5, Cd: 0.93-1.80; Cu: 24.8-152; Fe: 3.2-410.9; Mn: 0.36-24.4; Se: 0.094-9.81 and Zn: 20.3-109.4. The shrimp muscle can be a good iron source (about 88.9 mg-1g dry weight). The distribution of Se concentration in tissues showed much variation between locations, and the concentration levels found in shrimp muscles of wild samples were high, where its levels in 67% of muscle and 50% of others tissues samples exceeded the ANVISA limit, indicating evidence of selenium bioaccumulation. Significant correlation was observed between the following pairs of elements: Fe-Zn (r= -0.70), Mn-Cu (r= -0.74), Se-Cu (r= -0.68), Se-Mn (r= 0.82) in the muscles; Fe-Al (r= 0.99), Mn-Al (r= 0.62), Mn-Fe (r= 0.62), Se-Al (r = 0.88), Se-Fe (r= 0.87), Se-Mn (r= 0.58) in the exoskeleton and Cu-Zn (r = 0.68), Al-Cu (r= 0.88), Fe-Cu (r= 0.95) and Fe-Al (r= 0.97) in the viscera.

Assessment of Trace Elements in Tissues of Fish Species: Multivariate Study and Safety Evaluation

Levels of As, Cd, Cr, Cu, Li, Mn, Mo, Ni, Pb, Sb and Se in muscle, gill, stomach, liver, kidney and gonad tissues of six different fish species ( Caranx latus, Bagre marinus, Archosargus rhomboidalis, Lutjanus synagris, Scomberomorus cavalla and Sphyraena guachancho) from the Todos os Santos Bay (Bahia State, Brazil) were evaluated. The elements were determined by inductively coupled plasma mass spectrometry (ICP-MS) after wet digestion using reflux system with a cold finger. The detected concentration ranges were as follows (mg kg -1 dry weight): < 0.49-27.31 for As, < 0.013-1.12 for Cd, 0.38-6.05 for Cr, 0.17-28.12 for Cu, < 0.092-1.19 for Li, 0.16-55.9 for Mn, < 0.034-1.24 for Mo, < 0.067-15.57 for Ni, < 0.013-0.60 for Pb, < 0.144 for Sb and 0.57-14.6 for Se. Highest concentrations of trace elements were observed in kidney, liver and gill tissues.

Assessment of essential elements and chemical contaminants in thirteen fish species from the Bay Aratu, Bahia, Brasil

Concentrations of ten elements (Cd, Cr, Cu, Fe, Ni, Pb, Se, Sr, V and Zn) were determinate in muscle tissues of 13 fish species from Aratu Bay, Bahia, Brazil by inductively coupled plasma optical emission spectrometry. The accuracy and precision of our results were checked by using two certified reference materials: BCR-422 cod muscle and SRM 1566b oyster tissue. The average trace element concentrations in the fish species varied in the following ranges, in μg g-1: 0.03-0.8 for Cr; 2.0-33.7 for Cu, 2.4-135.1 for Fe, 1.6-25.6 for Se; 1.6-35.1 for Sr; and 2.8-40.5 for Zn. The Diaptereus rhombeus (carapeba) specie presented the highest concentrations of Se, Cu and Fe. Chromium and Se were present at levels above the limit of tolerance allowed by the National Agency of Sanitary Vigilance (ANVISA). The results were also evaluated using the multivariate analysis techniques: principal component analysis (PCA) and hierarchical cluster analysis (HCA).

CONCENTRAÇÃO DE METAIS EM SEDIMENTOS DA LAGOA DO PARQUE METROPOLITANO DE PITUAÇU, SALVADOR, BAHIA, BRASIL

A lagoa de Pituacu esta inserida no Parque Metropolitano de Pituacu (PMP). Esta recebe efluentes domesticos e pluviais e encontra-se em um processo acelerado de degradacao ambiental. O presente trabalho teve como objetivo determinar a concentracao de metais pesados (Al, Cu, Fe, Mn, V) em sedimentos superficiais da lagoa do Parque Metropolitano de Pituacu, Salvador, Bahia, Brasil. Foram definidos 7 pontos amostrais. A determinacao de metais (Al, Cu, Fe, Mn e V) foi realizada utilizando a tecnica da espectrometria de emissao optica com plasma indutivamente acoplado (ICP OES). A faixa de concentracoes encontradas para os metais foram: Al (3.618-27.210 mg kg -1 ); Fe (11.968-122.030 mg kg -1 ); Mn (44,00-481,50 mg kg -1 ); V (25,00-111,50 mg kg -1 ) e Cu (4,05-25,50 mg kg -1 ). A ordem de concentracao nos diversos pontos foi Fe>Al>Mn>V>Cu ou Fe>Al>Mn=V>Cu, com as maiores e as menores concentracoes de todos os metais, encontradas nos pontos P1 e P3, respectivamente. Houve variacoes espaciais nas concentracoes dos metais, com maiores concentracoes nos pontos amostrais proximos de atividades antropicas (efluentes e atividade agricola). Esse estudo reporta niveis relativamente altos, especialmente para o V, indicando possiveis necessidades de ampliar acoes de preservacao ou monitoramento ambiental para evitar a acumulacao desses metais em niveis toxicos para a agua e para o sedimento.