RESUMO
Emodin is an anthraquinone secondary metabolite produced by several species of plants and fungi. Emodin is known for its pharmacological versatility, and, in the textile industry, for its good dyeing properties. However, its use in the textile industry can result in the formation and disposal of large volumes of wastewater. Emodin mutagenicity has been shown in bacteria and in human cells, but little is known about its possible toxic, genotoxic, or mutagenic effects in aquatic organisms. We have evaluated the eco/genotoxicity of emodin to aquatic organisms. Emodin was toxic to Daphnia similis (EC50 = 130 µg L-1) and zebrafish embryos (LC50 = 25 µg L-1). No toxicity was observed for Raphidocelis subcapitata, Ceriodaphnia dubia, or Parhyale hawaiensis. Additional biochemistry/molecular studies are needed to elucidate the toxic/mutagenic pathways of emodin in aquatic organisms. The PNEC value for emodin was 0.025 µg L-1. In addition to mutagenicity in the Salmonella/microsome assay, emodin was mutagenic in the micronucleus assay in the amphipod P. hawaiensis. Among the anthraquinone dyes tested to date, natural or synthetic, emodin was the most toxic to aquatic species.
Assuntos
Corantes , Daphnia , Emodina , Testes de Mutagenicidade , Poluentes Químicos da Água , Peixe-Zebra , Emodina/toxicidade , Emodina/análogos & derivados , Animais , Corantes/toxicidade , Daphnia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Mutagênicos/toxicidade , Testes para Micronúcleos , Antraquinonas/toxicidade , Antraquinonas/química , Embrião não Mamífero/efeitos dos fármacosRESUMO
The concept of sustainability has gained prominence in recent years, enhancing the need to develop products that are less harmful to the environment. Dyes are used by various industrial sectors and have a lot of market value; they are used on a large scale mainly by the textile industry that uses large volumes of water and is one of the main contributors to the contamination of water bodies. Some natural compounds, especially anthraquinones are re-emerging as possible alternatives to synthetic dyes, some of which are known for their toxic and/or mutagenic effects. The BioColour project (https://biocolour.fi/) which is interested in promoting the development of new alternative molecules to synthetic dyes, provided us highly purified anthraquinone dyes dermocybin and dermorubin (>98% purity) extracted from a specie of fungus Cortinarius sanguineus. Dyes were tested for their acute and chronic toxicity using different aquatic organisms. Dermorubin was not toxic to any of the organisms tested for the highest test concentration of 1 mg L-1 and it was the most promising dye. Dermocybin was toxic to Daphnia similis (EC50 = 0.51 mg L-1), Ceriodaphnia dubia (IC10 = 0.13 mg L-1) and Danio rerio embryos (extrapolated LC50 = 2.44 mg L-1). A safety limit, i.e, predicted no-effect concentration (PNEC) of 0.0026 mg L-1 was derived based on the toxicity of dermocybin. The PNEC value can be used to provide hazard information for future application in commercial dyeing processes. Then, we compared the toxicity of dermocybin and dermorubin with ecotoxicity data available in the literature on other anthraquinone dyes of natural and synthetic origin. Some natural dyes can be as toxic as synthetic ones, or more toxic when chronic effects are considered. Despite natural dyes being used since centuries past, there are few ecotoxicological studies available. This study is designed to help develop a more comprehensive understanding of their toxicological properties.
Assuntos
Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Daphnia , Peixe-Zebra , Corantes/toxicidade , Antraquinonas/toxicidade , ÁguaRESUMO
The ability to add value to waste materials from industrial operations has come to the attention of the wood processing industry, with reports, for example, of extracts from the bark tree conveying colour and UV protection to textile fibres. The objective of the present work was to expand our developments in this arena by using Copaifera langsdorffii Desf. bark extract as a natural dye for textile dyeing. A complete 2³-statistical experimental design and the central point was elaborated. The results showed that the optimal dyeing conditions were 98 °C, for 60 min, using undiluted bark extract. The dyed fabric was analysed by a spectrophotometer using the CIELAB system for evaluation of the colour strength. The results showed a K/S value of 5.78, and the dyed fabric had good colour fastness to rubbing and washing.
Assuntos
Corantes/isolamento & purificação , Fabaceae/química , Casca de Planta/química , Extratos Vegetais/química , Lã/química , Animais , Cor , Corantes/química , Extratos Vegetais/isolamento & purificação , Proteção Radiológica/métodos , Proteção Radiológica/normas , Espectrofotometria , Temperatura , Têxteis , Fatores de Tempo , Raios Ultravioleta , Lã/metabolismoRESUMO
When testing new products, potential new products, or their impurities for genotoxicity in the Ames test, the quantity available for testing can be a limiting factor. This is the case for a dye repository of around 98,000 substances the Max Weaver Dye Library (MWDL). Mutagenicity data on dyes in the literature, although vast, in several cases is not reliable, compromising the performance of the in silico models. In this report, we propose a strategy for the generation of high-quality mutagenicity data for dyes using a minimum amount of sample. We evaluated 15 dyes from different chemical classes selected from 150 representative dyes of the MWDL. The purity and molecular confirmation of each dye were determined, and the microplate agar protocol (MPA) was used. Dyes were tested at the limit of solubility in single and concentration-response experiments using seven strains without and with metabolic activation except for anthraquinone dyes which were tested with eight strains. Six dyes were mutagenic. The most sensitive was YG1041, followed by TA97a > TA98 > TA100 = TA1538 > TA102. YG7108 as well as TA1537 did not detect any mutagenic response. We concluded that the MPA was successful in identifying the mutagenicity of dyes using less than 12.5 mg of sample. We propose that dyes should be tested in a tiered approach using YG1041 followed by TA97a, TA98, and TA100 in concentration-response experiments. This work provides additional information on the dye mutagenicity database available in the literature.
Assuntos
Corantes/efeitos adversos , Corantes/química , Testes de Mutagenicidade/métodos , Mutagênicos/efeitos adversos , Mutagênicos/química , Conformação Molecular , Mutagênese/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , SolubilidadeRESUMO
Three compounds based on the phenyltetrazole system, 5-(4-hydroxyphenyl)tetrazole (LTz-1), 5-(4-methoxyphenyl)tetrazole (LTz-2) and 5-(4-hexyloxyphenyl)tetrazole (LTz-3), were synthesized and characterized as co-adsorbents in dye-sensitized solar cells (DSSCs). The effects of hydrophobic chain length of the co-adsorbent and the effects of tetrazole anchoring group on the properties of DSSCs containing the previously reported dye HD-2 were compared with the benchmark deoxycholic acid (DCA). The charge-transfer resistance of the dye/TiO2 interface followed the order HD-2-DCA > HD-2-LTz-2 > HD-2-LTz-3 > HD-2-LTz-1. However, the Voc of the dye HD-2 with co-adsorbent DCA was 0.66 V, for the dye HD-2 with co-adsorbent LTz-1, it was 0.70 V, for the dye HD-2 with co-adsorbent LTz-2, it was 0.68 V and for the dye HD-2 with co-adsorbent LTz-3, it was 0.67 V. Co-adsorbents LTz-1, LTz-2 and LTz-3 achieved a mean solar-to-power conversion efficiency (%η), for the three devices, of 8.29, 7.63 and 8.49, respectively, compared to 7.76 for DCA under the same experimental device conditions. For the LTz-3 co-adsorbent, the results can be attributed to the repellent effect of the long alkyl chain. For LTz-1 and LTz-2 co-adsorbents, it is possible that the more compact layer formed improves electron-injection efficiency into TiO2.
RESUMO
Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1.
Assuntos
Compostos Azo/análise , Cloro/química , Corantes/análise , Desinfecção/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Animais , Compostos Azo/toxicidade , Cromatografia Líquida de Alta Pressão , Corantes/toxicidade , Daphnia/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Testes de Toxicidade Aguda , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidadeRESUMO
To verify whether dyes emitted within the discharge of a dye processing plant were contributing to the mutagenicity repeatedly found in the Cristais River, Sao Paulo, Brazil, we chemically characterized the following mutagenic samples: the treated industrial effluent, raw and treated water, and the sludge produced by a Drinking Water Treatment Plant (DWTP) located approximately 6 km from the industrial discharge. Considering that 20% of the dyes used for coloring activities might be lost to wastewaters and knowing that several dyes have mutagenic activity, we decided to analyze the samples for the presence of dyes. Thin layer chromatographic analysis indicated the presence of three prevalent dyes in all samples, except for the drinking water. This combination of dyes corresponded to a commercial product used by the industry, and it tested positive in the Salmonella assay. The structures of the dye components were determined using proton magnetic resonance and mass spectrometric (MS) methods, and the dyes were tested for mutagenicity. The blue component was identified as the C.I. Disperse Blue 373, the violet as C.I. Disperse Violet 93, and the orange as C.I. Disperse Orange 37. The dyes showed mutagenic responses of 6300, 4600, and 280 revertants/microg for YG1041 with S9 respectively. A bioassay-directed fractionation/chemical analysis showed that the C.I. Disperse Blue 373 contributed 55% of the mutagenic activity of the DWTP sludge. We showed that these dyes contributed to the mutagenic activity found in the Cristais River environmental samples analyzed and are indirectly affecting the quality of the related drinking water. Therefore, we believe that this type of discharge should be more thoroughly characterized chemically and toxicologically. Additionally, human and ecological risks associated with the release of dye processing plant effluents should be more fully investigated, especially where the resultant water is taken for human consumption.
Assuntos
Compostos Azo/toxicidade , Corantes/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Compostos Azo/química , Bioensaio , Brasil , Cromatografia em Camada Fina , Corantes/química , Água Doce/análise , Técnicas In Vitro , Resíduos Industriais/efeitos adversos , Resíduos Industriais/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Microssomos Hepáticos/metabolismo , Testes de Mutagenicidade , Mutagênicos/química , Ratos , Salmonella/efeitos dos fármacos , Indústria Têxtil , Poluentes Químicos da Água/análise , Abastecimento de Água/análiseRESUMO
Textile dyes can enter the water ecosystem through wastewater discharges potentially exposing humans through the consumption of water and food. The commercial disperse dye product CI Disperse Blue 291 containing the aminoazobenzene 2-[(2-bromo-4,6-dinitrophenyl)azo]-5-(diethylamino)-4-methoxyacetanilide (CAS registry no. 56548-64-2) was tested for mutagenic activity in the Salmonella assay. We used strains with different levels of nitroreductase and O-acetyltransferase (i.e., TA98DNP6, YG1024, and YG1041) that are relevant enzymes in the activation of nitrocompounds by the intestinal microflora. The commercial product tested also was mutagenic for TA1537, TA1538, TA98 and TA100. Presence of the pKM101 plasmid and the addition of S9 enhanced the mutagenic response. Specialized strains showed that both nitroreductase and O-acetyltransferase are important in activation of the product. The highest potency obtained was 240 revertants per microgram for YG1041 in the presence of S9. Besides being able to cause frameshift mutations (hisd3052), the dye was able to cause all types of base pair substitution with a preference for TA to AT; CG to TA and CG to AT changes. With these results clearly showing that the bacterial nitroreductase and O-acetyltransferase metabolites of this compound are mutagenic, there is a need to test this dye using in vivo systems to verify possible adverse effects of this product in mammalian tissues.