VANESSA SILVA GRANADEIRO GARCIA

Projetos de Pesquisa
Unidades Organizacionais
Cargo

Resultados de Busca

Agora exibindo 1 - 3 de 3
  • Artigo IPEN-doc 27915
    Electron beam irradiation of combined pharmaceuticals
    2021 - BOIANI, NATHALIA F.; GARCIA, VANESSA S.G.; BORRELY, SUELI I.
    There are serious evidences that justify the search for treatment technologies or processes combination for the improvement of decomposition for dozens of pharmaceuticals in wastewaters. Electron beam irradiation may play an important role in this scenario and relatively low doses have been reported for such purposes. The aim of the present study was to evaluate the toxic response of the crustacean Daphnia similis exposed to individual and combined pharmaceuticals, before and after electron beam irradiation treatment. Several experimental trials of an acute immobilization test were performed with a mixture of pharmaceuticals composed of fluoxetine hydrochloride (Prozac®), and propranolol. Single pharmaceuticals were first tested separately. Toxicity of binary mixture was then assessed using five concentrations and five percentages of each substance in the mixture (0, 25, 50, 75, and 100%). Acute EC50% values ranged from 5.0 to 7.4 for fluoxetine and from 11.3 to 13.7 for propranolol. In mixture, values ranged from 6.4 to 9.8. Fluoxetine was more toxic than propranolol for D.similis. The different pharmaceuticals concentrations employed in a mixture showed no difference in toxicity values. When electron beam irradiation was applied, approximately 80% of acute effects were reduced at 5 kGy, and the mixture containing a higher percentage of fluoxetine, also showed a greater reduction of toxicity.
  • Artigo IPEN-doc 27859
    Toxicity and color reduction of reactive dyestuff RB 21 and surfactant submitted to electron beam irradiation
    2021 - MELO, C.G.; ROSA, J.M.; GARCIA, V.S.G.; BORRELY, S.I.; PEREIRA, M.C.C.
    There is an unwelcome reaction between the coloring and the water during the dyeing procedure, a portion of the coloring agent is lost in the bathing and it will compose the final whole effluent. The high absorbance index is related to lost dyestuffs and they also contribute with the toxic effects to the aquatic biota. In addition, these effluents contain large quantity of surfactants applied during dyeing baths, which also contribute to the high toxicity in these samples. The objective of this study was to evaluate electron beam irradiation technology, applied in samples of the Color Index Reactive Blue 21 (RB 21) dyestuff and in samples of surfactant non-ionic and in order to reduce toxicity for both and for RB 21, color reduction. Among the objectives of the study there are the dyestuff exhaustion degree, and some physical-chemical parameters. The acute toxicity assays were carried with Daphnia similis microcrustacean and the results of the dyestuff solution were: the irradiated samples with concentration 0.61 g L-1 did not present significant results, the EC 50 (%) value was to 58.26 for irradiated sample with 2.5 kGy and EC 50 (%) 63.59 for sample irradiated with 5 kGy. The surfactant was more toxic than RB 21, with EC 50 (%) value at 0.42. The color reduction reached 63.30% for the sample of the lowest concentration of effluent. There was a reduction of pH during irradiation.
  • Artigo IPEN-doc 25766
    Electron beam irradiation of textile effluents and non-ionic ethoxylated surfactant for toxicity and color removal
    2019 - BORRELY, S.I.; SILVA, L.G.A.; DEL SOLE, S.V.; GARCIA, V.S.G.; BOIANI, N.F.; ROSA, J.M.
    Textile industry has an expressive scenario in the world economy and Brazil is the 5th in the textile production. By 2015, Brazilian textile production represented US $ 39.3 billion, accounting for more than 1.8 million tons of fabric. The effluents from textile industry are highlighted by quantity of wastewater discharged and variety of substances (dyes, bleaching agents, surfactants, salts, acids, among others). Such compounds often prove to be toxic to aquatic biota. This present study aims to assess toxicity of whole effluents, before and after irradiation (by electron beam accelerator, EBI). In addition, the reduction of the effluent color after irradiation is also very important. Daphnia similis and Vibrio fischeri were the biological systems applied for toxicity evaluations. Previous results demonstrated the surfactant as the main toxic compound, in the untreated and irradiated forms, EC 50 = 0.44 ppm ± 0.02 (untreated); EC 50 = 0.46 % ± 0.07 (irradiated). The irradiation was effective for reducing color of the effluent, starting from 0.5 kGy. EB irradiation may be proposed as an alternative treatment for the final effluent from textile processing, mainly for reuse purposes.