Cytotoxic and genotoxic effects of silver nanoparticle/carboxymethyl cellulose on <Emphasis Type="Italic">Allium cepa</Emphasis>

Several mutagenic agents may be present in substances released in the environment, which may cause serious environmental impacts. Among these substances, there is a special concern regarding the widespread use of silver nanoparticles (AgNP) in several products due to their widely known bactericidal properties, including in the medical field and the food industry (e.g., active packaging). The assessment of the effects of AgNP released in the environment, having different concentrations, sizes, and being associated or not to other types of materials, including polymers, is therefore essential. In this research, the objective was to evaluate the genotoxic and cytotoxic effects of AgNP (size range between 2 and 8 nm) on root meristematic cells of Allium cepa (A. cepa). Tests were carried out in the presence of colloidal solution of AgNP and AgNP mixed with carboxymethylcellulose (CMC), using distinct concentrations of AgNP. As a result, when compared to control samples, AgNP induced a mitotic index decrease and an increase of chromosomal aberration number for two studied concentrations. When AgNP was in the presence of CMC, no cytotoxic potential was verified, but only the genotoxic potential for AgNP dispersion having concentration of 12.4 ppm.     

Influence of the current density on the electrochemical treatment of concentrated 1-butyl-3-methylimidazolium chloride solutions on diamond electrodes

This paper focuses on the influence of the current density treatment of a concentrated 1-butyl-3-methylimidazolium chloride (BMImCl) solution on an electrochemical reactor with a boron-doped diamond (BDD) anode. The decrease in the total organic carbon (TOC) and the BMImCl concentration demonstrate the capability of BDD in oxidizing ionic liquids (ILs) and further mineralizing (to CO₂ and NO₃ ^?) more rapidly at higher current densities in spite of the reduced current efficiency of the process. Moreover, the presence of Cl^? led to the formation of oxychlorinated anions (mostly ClO₃ ^? and ClO₄ ^?) and, in combination with the ammonia generated in the cathode from the nitrate reduction, chloramines, more intensely at higher current density. Finally, the analysis of the intermediates formed revealed no apparent influence of the current density on the BMImCl degradation mechanism. The current density presents therefore a complex influence on the IL treatment process that is discussed throughout this paper.     

Activity of the endophytic fungi <Emphasis Type="Italic">Phlebia</Emphasis> sp. and <Emphasis Type="Italic">Paecilomyces formosus</Emphasis> in decolourisation and the reduction of reactive dyes’ cytotoxicity in fish erythrocytes

The current study investigates the potential for discolouration and degradation of Reactive Blue 19 and Reactive Black 5 textile dyes by endophytic fungi Phlebia sp. and Paecilomyces formosus as well as the potential cytotoxicity of products or by-products generated by the treatments in fish erythrocytes. It was observed at 30 days that both endophytes showed biodegradation activity with 0.1 g mL^?1 of dyes. P. formosus showed highest extracellular and intracellular protein content levels after the 15th day, and Phlebia sp. stands out for production of extracellular laccase, indicating that this enzyme may be associated with the decolouration capacity. The dyes showed toxic effects in fishes at 0.01 g mL^?1 concentration, resulting in the appearance of micronuclei in erythrocyte cells. When degraded dyes treated by endophytes were tested, the frequency of micronuclei reduced approximately 20%, indicating the effectiveness of these endophytic in the treatment of textile dyes with less environmental impact, thus indicating a potential for application of these fungi in bioremediation process.     

Natural resource industry involvement in collaboration for water governance: influence on processes and outcomes in Canada

Natural resource industries are increasingly significant actors in environmental decision-making. Possessing vast institutional and technical capacity, firms have an important role to play in ‘new’ governance strategies such as collaboration. These strategies are often based upon assumptions of equitable influence. This paper investigates the nature of resource industry participation in collaborative water governance in Canada, and the potential consequences of that participation as investigated using power theory. The study used comparative cases to reveal that resource industries are able to shape collaboration, and the issues collaborated upon, at multiple analytical levels both internal and external to the collaborative process in ways not available to other actors. Analysis also revealed that resource industry participation in collaboration did not reflect a commitment to engage in shared learning and the reexamination of values and interests as presupposed by collaborative theory. Collaboration is thus challenged in producing equitable, representative outcomes when resource industries participate.     

Correction to: Estimating the urban environmental impact of gasoline-ethanol blended fuels in a passenger vehicle engine

Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org10.1007/s11356-021-13920-8