Superação de dormência de sementes e crescimento inicial de plântulas de umbuzeiro

Pre-germination treatments such as scarification and the use of growth regulators can provide the overcoming of dormancy in seeds and enhance the emergence and development of seedlings. The aim of this study was to determine appropriate treatments to overcoming seed dormancy and enhance the initial growth of seedlings of Spondias tuberosa. We used a randomized design in factorial 2 x 4, with the following factors: seeds scarified or not scarified and then soaked in water or aqueous solutions of gibberellin, cytokinin and ethylene, with 4 replicates and 15 seeds. There was no significant interaction between scarification treatments and use of growth regulators. Mechanical scarification and soaking of seed of umbuzeiro in solutions containing growth regulators does not increase the percentage of seedling emergence, however soaking in a solution of Ethrel at 100 ppm provides higher speed of emergence and root development.

Frutos de umbuzeiro (Spondias tuberosa Arruda): características físico-químicas durante seu desenvolvimento e na pós-colheita

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Subchronic Toxicity Evaluation of a Treated Urban Sewage Sludge

Disposal of tons of sludge produced daily by sewage treatment plants in large cities is a serious problem. Because recycling and application in agriculture have been proposed, the Brazilian National Environmental Council (CONAMA, 2006) issued a legal norm that regulates the use of the sewage sludge (SS) in crops. Due to the complex chemical nature of such products, characterization by analytical methods for health and environmental risk assessment has severe limitations. To overcome such limitations, it is necessary to (1) assess the toxicological potential of SS and (2) identify possible adverse effects in vivo in order to provide critical information for future environmental regulations. The present study was conducted to determine the potential toxicity of SS obtained from a representative urban treatment plant located in the São Paulo State, Brazil. Male and female Wistar rats were fed ad libitum a pelleted diet containing varying amounts of SS. No relevant clinical, hematological, urinary, or gross organ morphological alterations were observed in both genders of rats orally exposed to SS at up to 3.8 g/kg/d for 90 d. Sewage slude produced increased incidence of centrilobular hepatocyte hyperplasia at the high dose and significantly increased aspartate aminotransferease (AST) activities at all doses in both genders. Although the present data indicate some liver involvement, these alterations were considered adaptative and not toxicologically relevant, as the responses were relatively mild, not dose dependent, and no other parameters were markedly affected. The present results may contribute to the establishment of protocols for potential usage in SS agricultural soil application.

Mutagenic and carcinogenic potential of a textile azo dye processing plant effluent that impacts a drinking water source

Recently a textile azo dye processing plant effluent was identified as one of the sources of mutagenic activity detected in the Cristais River, a drinking water source in Brazil [G.A. Umbuzeiro, D.A. Roubicek, C.M. Rech, M.I.Z. Sato, L.D. Claxton, Investigating the sources of the mutagenic activity found in a river using the Salmonella assay and different water extraction procedures, Chemosphere 54 (2004) 1589-1597]. Besides presenting high mutagenic activity in the Salmonella/microsome assay, the mutagenic nitro-aminoazobenzenes dyes CI Disperse Blue 373, Cl Disperse Violet 93, and CI Disperse Orange 37 [G.A. Umbuzeiro, H.S. Freeman, S.H. Warren, D.P Oliveira, Y. Terao, T. Watanabe, L.D. Claxton, the contribution of azo dyes in the mutagenic activity of the Cristais river, Chemosphere 60 (2005) 55-64] as well as benzidine, a known carcinogenic compound [T.M. Mazzo, A.A. Saczk, G.A. Umbuzeiro, M.V.B. Zanoni, Analysis of aromatic amines in surface waters receiving wastewater from textile industry by liquid chromatographic with eletrochemical detection, Anal. Lett., in press] were found in this effluent. After similar to 6 km from the discharge of this effluent, a drinking water treatment plant treats and distributes the water to a population of approximate 60,000. As shown previously, the mutagens in the DWTP intake water are not completely removed by the treatment. The water used for human consumption presented mutagenic activity related to nitro-aromatics and aromatic amines compounds probably derived from the cited textile processing plant effluent discharge [G.A. Umbuzeiro, D.A. Roubicek, C.M. Rech, M.I.Z.. Sato, L.D. Claxton, Investigating the sources of the mutagenic activity found in a river using the Salmonella assay and different water extraction procedures, Chemosphere 54 (2004) 1589-1597; G.A. Umbuzeiro, H.S. Freeman, S.H. Warren, D.P. Oliveira, Y. Terao, T. Watanabe, L.D. Claxton, the contribution of azo dyes in the multagenic activity of the Cristais river, Chemosphere 60 (2005) 55-64]. Therefore, it is important to evaluate the possible risks involved in the human consumption of this contaminated water. With that objective, one sample of the cited industrial effluent was tested for carcinogenicity in the aberrant crypt foci medium-term assay in colon of Wistar rats. The rats received the effluent in natura through drinking water at concentrations of 0.1%, 1%, and 10%. The effluent mutagenicity was also confirmed in the Salmonella/microsome assay with the strains TA98 and YG1041. There was an increased number of preneoplastic lesions in the colon of rats exposed to concentrations of 1% and 10% of the effluent, and a positive response for both Salmonella strains tested. These results indicate that the discharge of the effluent should be avoided in waters used for human consumption and show the sensitivity of the ACF crypt foci assay as an important tool to evaluate the carcinogenic potential of environmental complex mixtures. (c) 2006 Elsevier B.V. All rights reserved.

In vivo genotoxicity evaluation of a treated urban sewage sludge sample

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotoxic, mutagenic and cytotoxic effects of the commercial dye CI Disperse Blue 291 in the human hepatic cell line HepG2

Textile dyes are discarded into the aquatic ecosystem via industrial effluents and potentially expose humans and local biota to adverse effects. The commercial dye CI Disperse Blue 291 which contains the aminoazobenzene 2-[(2-bromo-4,6-dinitrophenyl)azo]-5(diethylamino)-4-methoxyacetanilide (CAS registry no. 56548-64-2), was tested for genotoxicity and cytotoxicity in the human hepatoma cell line HepG2, using the comet assay, micronucleus (MN) test and a cell viability test. Five different concentrations of the test compound were examined: 200 mu g/ml, 400 mu g/ml, 600 mu g/ml, 800 mu g/ml and 1000 mu g/ml. An increase in comet tail length and in the frequency of MN was detected with exposure of cells to concentrations of the commercial dye from 400 pg/ml. Furthermore, the dye was found to decrease cell viability. The results of this study demonstrate for the first time the genotoxic and mutagenic effects of the dye CI Disperse Blue 291 in mammalian cells, thus stressing the need to develop non-mutagenic dyes and to invest in improving the treatment of effluents. These measures will help to prevent harmful effects that these compounds can have on humans and aquatic organisms that come in contact with them. (C) 2007 Elsevier Ltd. All rights reserved.

Mutagenic activity removal of selected disperse dye by photoeletrocatalytic treatment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Assessment of water contamination caused by a mutagenic textile effluent/dyehouse effluent bearing disperse dyes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessment of by-products of chlorination and photoelectrocatalytic chlorination of an azo dye

The present work describes a more efficient methodology for the chlorination of water containing disperse dyes, where the chlorinated byproducts identified by mass spectra are compared. this investigation, we tested the degradation of Cl Disperse Blue 291 dye, 2-[(2-Bromo-4,6-dinitrophenyl)azo]-5-(diethylamino)-4-methoxyacetanilide) a commercial azo dye with mutagenic properties. The present work evaluates the photoelectrocatalytic efficiency of removing the Cl Disperse Blue 291 dye from a wastewater of the textile industry. We employed NaCl as a supporting electrolyte. It should be noted that photoelectrocatalytic techniques are non-conventional method of generating chlorine radicals. The by-products formed in this process were analyzed using spectrophotometry, liquid chromatography, dissolved organic carbon, mass spectral analysis and mutagenicity assays. The process efficiency was compared with the conventional chlorination process adopted during sewage and effluents treatment processes. This conventional chlorination process is less efficient in removing color, total organic carbon than the photoelectrochemistry technique. Furthermore, we shall demonstrate that the mutagenicity of the generated by-products obtained using photoelectrocatalysis is completely different from that obtained by the conventional oxidation of chloride ions in the drinking wafer treatment process. (C) 2012 Published by Elsevier B.V.

Differential Toxicity of Disperse Red 1 and Disperse Red 13 in the Ames Test, HepG2 Cytotoxicity Assay, and Daphnia Acute Toxicity Test

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mutagenic compounds generated from the chlorination of disperse azo-dyes and their presence in drinking water

The water produced by the Cristais River Drinking Water Treatment Plant (CR-DWTP) repeatedly produced mutagenic responses that could not be explained by the presence of disinfection byproducts (DBPs) generated by the reaction of humic acids and chlorine. In order to determine the possible role of chlorinated dye products in this mutagenic activity, solutions of a black dye commercial product (BDCP) composed of C. I. Disperse Blue 373, C. I. Disperse Orange 37, C. I. Disperse Violet 93, and chemically reduced BDCP (R-BDCP) were chlorinated in a manner similar to that used by the CR-DWTP. The resulting solutions were extracted with XAD-4 along with one drinking water sample collected from the CR-DWTP. All extracts showed mutagenic activity in the Salmonella/microsome assay. Dye components of the BDCP as well as its reduced chlorinated (Cl-R-BDCP) derivative were detected in the drinking water sample by analysis with a high performance liquid chromatography/diode array detector (HPLC/DAD). The mutagenicity results of these products suggest that they are, at least in part, accounting for the mutagenic activity detected in the drinking water samples from the Cristais River. The data obtained in this study have environmental and health implications because the chlorination of the BDCP and the R-BDCP leads to the formation of mutagenic compounds (Cl-BDCP and Cl-R-BDCP), which are potentially important disinfection byproducts that can contaminate the drinking water as well as the environment.

Chemical characterization of a dye processing plant effluent - Identification of the mutagenic components

This work shows the chemical characterization of a dye processing plant effluent that was contributing to the mutagenicity previously detected in the Cristais river, São Paulo, Brazil, that had an impact on the quality of the related drinking water. The mutagenic dyes Disperse Blue 373, Disperse Orange 37 and Disperse Violet 93, components of a Black Dye Commercial Product (BDCP) frequently used by the facility, were detected by thin layer chromatography (TLC). The blue and orange dyes were quantified by high performance liquid chromatography (HPLC/DAD) in a raw and treated effluent samples and their contribution to the mutagenicity was calculated based on the potency of each dye for the Salmonella YG1041. In the presence of S9 the Disperse Blue 373 accounted for 2.3% of the mutagenic activity of the raw and 71.5% of the treated effluent. In the absence of S9 the Disperse Blue 373 accounted for 1.3% of the mutagenic activity of the raw and 1.5% of the treated effluent. For the Disperse Orange 37, in the presence of S9, it contributed for 0.5% of the mutagenicity of the raw and 6% of the treated effluent. In the absence of S9; 11.5% and 4.4% of the raw and treated effluent mutagenicity, respectively. The contribution of the Disperse Violet 93 was not evaluated because this compound could not be quantified by HPLC/DAD. Mutagenic and/or carcinogenic aromatic amines were also preliminary detected using gas chromatograph/mass spectrometry in both raw and treated and are probably accounting for part of the observed mutagenicity. The effluent treatment applied by the industry does not seem to remove completely the multagenic compounds. The Salmomella/microsome assay coupled with TLC analysis seems to be an important tool to monitor the efficiency of azo dye processing plant effluent treatments. (c) 2006 Elsevier B.V. All rights reserved.

Analysis of aromatic amines in surface waters receiving wastewater from a textile industry by liquid chromatographic with electrochemical detection

A high performance liquid chromatography ( HPLC) method with electrochemical detection (ED) was developed for the determination of benzidine, 3,3-dimethylbenzidine, o-toluidine and 3,3-dichlorobenzidine in the wastewater of the textile industry. The aromatic amines were eluted on a reversed phase column Shimadzu Shimpack C-18 using acetonitrile + ammonium acetate (1 x 10(-4) mol L-1) at a ratio 46: 54 v/v as mobile phase, pumped at a flow rate of 1.0 mL min(-1). The electrochemical oxidation of the aromatic amines exhibits well-defined peaks at a potential range of +0.45 to +0.78 V on a glassy carbon electrode. Optimum working potentials for amperometric detection were from 0.70 V to +1.0 V vs. Ag/AgCl. Analytical curves for all the aromatic amines studied using the best experimental conditions present linear relationship from 1 x 10(-8) mol L-1 to 1.5 x 10(-5) mol L-1, r = 0.99965, n = 15. Detection limits of 4.5 nM (benzidine), 1.94 nM (o-toluidine), 7.69 nM (3,3-dimethylbenzidine), and 5.15 nM (3,3-dichlorobenzidine) were achieved, respectively. The detection limits were around 10 times lower than that verified for HPLC with ultra violet detection. The applicability of the method was demonstrated by the determination of benzidine in wastewater from the textile industry dealing with an azo dye processing plant.

Photoelectrocatalytic oxidation of remazol turquoise blue and toxicological assessment of its oxidation products

The ability of photoelectrocatalytic oxidation to degrade the commercially important copper-plitalocyanine dye, remazol turquoise blue 15 (RTB) was investigated. The best experimental condition was optimized, evaluating the performance of Ti/TiO2 thin-film electrodes prepared by sol-gel method in the decolourization of 32 mg L-1 RTB dye in 0.5 mol L-1 Na2SO4 pH 8 and applied potential of +1.5 V versus SCE under UV irradiation. Spectrophotometric measurements, high performance liquid chromatography, dissolved organic carbon (TOC) evaluation and stripping analysis of yielding solution obtained after 3 h of photoelectrolysis leads to 100% of absorbance removal from wavelength of 250-800 nm, 79.6% of TOC reduction and the releasing of up to 54.6% dye-bound copper (0.85 mg L-1) into the solution. Both, original and oxidized dye solution did not presented mutagenic activity with the strains TA98 and WOO of Salmonella in the presence and absence of S9 mix at the tested doses. Nevertheless, the yielding photoelectrocatalytic oxidized solution showed an increase in the acute toxicity for Vibrio fischeri bacteria, explained by copper liberation during treatment. (c) 2006 Elsevier B.V. All rights reserved.