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Andreu-Sanchez O.,Polytechnic University of Valencia | Paraiba L.C.,Embrapa Meio Ambiente Embrapa Environment | Jonsson C.M.,Embrapa Meio Ambiente Embrapa Environment | Carrasco J.M.,Polytechnic University of Valencia
Environmental Toxicology | Year: 2012

This research work investigated the bioconcentration of tebuconazole [(±)-α-[2-(4-chlorophenyl)ethyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol] fungicide in zebrafish (Danio rerio) under laboratory conditions and a first-order kinetic pesticide dissipation in the water. The concentrations of tebuconazole fitted to an equivalent nonlinear kinetic type model which allowed the calculation of the following parameters: bioconcentration factor (38.80 L kg -1), time to reach maximum fish concentration (6 days), maximum concentration in fish (0.0075 μg mg -1), half-life in fish (24 days) and time needed for the fish to eliminate 95% of the maximum concentration (105 days). These calculations permitted the establishment of theoretical reference limit values for human consumption of fish and the establishment of safe limits for the water pesticide concentration. The data would also be useful in safe strategies associated with fishery activities that are conducted in aquatic regions close to crops using tebuconazole. The information will contribute to enlarge the tebuconazole toxicokinetics database of aquatic organisms. © 2011 Wiley Periodicals, Inc.

Paraiba L.C.,Embrapa Meio Ambiente Embrapa Environment | Queiroz S.C.N.,Embrapa Meio Ambiente Embrapa Environment | Maia A.D.H.N.,Embrapa Meio Ambiente Embrapa Environment | Ferracini V.L.,Embrapa Meio Ambiente Embrapa Environment
Science of the Total Environment | Year: 2010

This study presents a model to simulate the organic substance concentrations in corn grains assuming that the substances in soil solution are absorbed via the transpiration stream by plants growing in soils fertilized with sewage sludge (SS). The model was applied and validated using soil and corn grain samples from a long-term field experiment with six successive yearly applications of SS to the soil. The following polycyclic aromatic hydrocarbons (PAHs) were simulated and evaluated in soil and grain samples: acenaphthene, acenaphthylene, anthracene, benz(a)anthracene, benz(a)pyrene, benz(b)fluoranthene, benz(g,h,i)perylene, benz(k)fluoranthene, chrysene, dibenz(a,h)anthracene, fluoranthene, fluorene, indeno(1,2,3-c,d)pyrene, naphthalene, phenanthrene and pyrene. The PAH bioconcentration factors (BCF) in corn grains ranged from 1.57 to 10.97Lkg-1. Polycyclic aromatic hydrocarbons with low soil distribution coefficients and high values of transpiration stream concentration factors (TSCF) are more likely to be absorbed by corn plants and accumulated in grains. It was possible to estimate and observe that highly lipophilic PAH molecules (heavy PAHs) show lower accumulative potential in corn grains than the less lipophilic ones (light PAHs). Sewage sludges containing significant concentrations of light PAHs with two, three or four benzene rings should be avoided as fertilizers in alimentary field crops. © 2010 Elsevier B.V.

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