Gas hazard of explosives used in the mining industry

Reducing emissions of hazardous pollutants that have a negative impact on the environment and human health has been approved as one of the strategic objectives of Russia's development. More than 90% of minerals in mined using blast energy. Despite an increase in the share of non-explosive component mixtures used in mining, blasting still poses a hazard to miners as the gaseous detonation products are potentially dangerous. The composition of blast gaseous products is extremely important in underground blasting because air exchange is difficult under these conditions and the blast products can contaminate the atmosphere of underground excavations, causing illness or poisoning of miners. Currently, there are no uniform requirements for obtaining information on the amount of gaseous blast products that would be hazardous to the human organism. Available documents do not contain information on the permissible amounts of toxic oxides per 1 kg of explosive detonated. The article compares the results of studying gas toxic hazard of industrial explosives obtained by different methods and based on different criteria.

Astaxanthin Mitigates Thiacloprid-Induced Liver Injury and Immunotoxicity in Male Rats

Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection.

A Comparative Study on Mineral Contents of Soybean by Two Methods of Digestion Using ICP-OES Technique: A Risk Assessment Study

Introduction: In recent years, the contamination of food with heavy metals has received much attention. Plants can absorb metal pollutants through contaminated water, soil, and air. Materials and Methods: In the current study, accumulation of minerals in three types of soybeans was investigated by wet and dry digestion methods using ICP-OES technique. Thereafter, the metals' health risk was assessed by estimated daily intake, toxic hazard quotient (THQ), and hazard index (HI) values. Results: According to the results, the concentrations of Cr, Se, Ca, Fe, Mo, Mn, and Mg in soybean seeds were 0.034-170.88 mg/kg, 0.21-243.79 mg//kg, 2.50-33.37 mg/kg, 0.05-0.86 mg/kg, 0.071-203.57 mg/kg, 0-0.47 mg/kg, and 2.69-19.31 mg/kg, respectively. The ashing method had a better performance in determining Ca, Fe, Mo, Mn, and Mg concentrations than the wet digestion method. The THQ rates were below 1 for the three varieties of each mineral element, but the HI values of variety 2 and variety 3 were higher than 1 in both methods. Conclusion: Furthermore, continuous monitoring of the soybeans' mineral and heavy metal contents seems necessary

Mechanism of birnessite-promoted oxidative dissolution of antimony trioxide

Environmental contextThe release of antimony and its compounds to the environment can present a toxic hazard for humans. We evaluated the use of birnessite to dissolve antimony trioxide and found that birnessite accelerated the dissolution process, and ~50% of the oxidised antimony was absorbed. The results can help evaluate the bioavailability of antimony in the environment. AbstractThe most important naturally occurring forms of antimony (Sb) are the ore mineral stibnite (Sb2S3) and its principal weathering product antimony trioxide (Sb2O3). Moreover, most Sb is released into the environment as Sb2O3 from manufacturing, formulations, processing, and the use and disposal of Sb products. In this study, birnessite (δ-MnO2) was employed to promote Sb2O3 dissolution. The Sb2O3 dissolution rate accelerated from ~2% to >99% after 9 days of reaction, and more than 98% of the dissolved SbIII was oxidised into SbV in the presence of birnessite. The birnessite-promoted oxidative dissolution mechanism of Sb2O3 was studied through experiments on the effects of the reaction time and pH. The release rate of Sb in the aqueous phase at the initial stage (335.4 μmol L−1 day−1, pH 6.5) was much higher than that at the late stage (13.28 μmol L−1 day−1, pH 6.5), and when the pH increased from 4.7 to 8.0, the Sb release rate decreased from 351.2 μmol L−1 day−1 to 257.7 μmol L−1 day−1. The dissolution promotion effects of birnessite on Sb2O3 were the most evident under acidic and neutral conditions (the percentages of dissolved Sb2O3 under acidic and neutral conditions were 98.3% and 100.0% after 9 days of reaction). Not all of the produced SbV was released in the reaction solution because ~50% of it was adsorbed by birnessite, and the amount of Sb adsorbed increased with increasing pH. Therefore, alkaline conditions are shown to reduce the release of SbV by inhibiting Sb2O3 dissolution (86.7%) and enhancing SbV adsorption. These results could help clarify the geochemical cycle and fate of Sb in the environment.

Assessing the risk from the depleted uranium weapons used in Operation Allied Force

The conflict in Yugoslavia has been a source of great concern for the neighboring countries, about the radiological and toxic hazard posed by the alleged presence of depleted uranium in NATO weapons. In the present study a worst-case scenario is assumed mainly to assess the risk for Greece and other neighboring countries of Yugoslavia at similar distances . The risk of the weapons currently in use is proved to be negligible at distances greater than 100 Km. For shorter distances classified data of weapons composition are needed to obtain a reliable assessment.

Preparation of Cobalt Ferrite Nanoparticle-Decorated Boron Nitride Nanosheet Flame Retardant and Its Flame Retardancy in Epoxy Resin

Boron nitride nanosheet (BNNS) decorated with cobalt ferrite nanoparticle (CFN) to afford CFN-BNNS nanohybrid was prepared via a simple hydrothermal route and was well characterized. Subsequently, the as-prepared CFN-BNNS nanohybrid was incorporated into epoxy resin (EP) with the introduction of a weak rotary magnetic field to achieve order orientation, in order to reduce the fire risk and toxic hazards using enhanced shielding effect of BNNS upon combustion. Findings demonstrate that the CFN-BNNS nanohybrid is composed of CFN nanoparticle uniformly dispersed on BNNS surface. Thermal analysis and cone calorimeter data show that the CFN-BNNS nanofiller among EP matrix contributes to improving the char residues and mechanical properties of EP and reducing its fire risk as well as toxic hazards, especially the ordered one is advantageous over the disordered one in reducing the fire risk and toxic hazard. This is because, on the one hand, the orderly aligned BNNS as the physical barrier can more effectively prevent the transfer and diffusion of oxygen and heat. On the other hand, CFN can catalyze the degradation of EP to afford excessive chars on polymer surface; and it is also liable to decomposition during combustion, thereby generating ferrite species to promote EP degradation as well as cobalt species to enhance the oxidation of CO.

Biosorption of residual cisplatin, carboplatin and oxaliplatin antineoplastic drugs in urine after chemotherapy treatment

Environmental contextPlatinum complexes are widely used to treat cancer; however, these compounds are also rapidly excreted in the urine of patients and can therefore enter waterways, presenting a toxic hazard to the environment. The biopolymer chitosan was found to be an effective and fast adsorbent for capturing multiple platinum complexes currently applied in medicine. This new approach using biomaterials is proposed to treat such drug residues while at the same time recovering the valuable metal from urine. AbstractThe majority of platinum used in antineoplastic drugs is rapidly excreted through the urine. These residual platinum compounds are highly toxic, and may eventually reach the aquatic environment if not remediated. Furthermore, platinum is a precious metal that is also relatively scarce, and it is therefore also economically worthwhile to capture and recycle it. We propose that biomass-derived adsorbents would be effective for recovering platinum from diluted streams, including synthetic human urine. Compared with ultrapure water, the salts and small biomolecules present in urine pose additional competition for active binding on the biosorbents’ surface. Chitosan, biochar, wood ash and granular activated carbon were found to effectively adsorb between 0.23 and 0.97mgg−1 inorganic PtIV when a minimal adsorbent dose of 10gL−1 was applied. The fastest adsorption rate was observed using chitosan (k2=728gmg−1min−1), followed by wood ash (k2=49.4gmg−1min−1) and biochar (k2=6.18gmg−1min−1). Substantial differences in platinum recovery were observed among inorganic PtIV, cisplatin, carboplatin and oxaliplatin, which indicates that the adsorbate speciation is highly important for establishing a hydrometallurgical purification technique.

Utilization of Assisted Hatching Techniques to Enhance Embryo Implantation

Gestation is the main goal for <em>in vitro</em> fertilization. The embryo that has been developed outside the body will be transferred directly into uterus leading to the process of hatching, implantation, and pregnancy. However, approximately 85% of embryos that have been transferred were failed to implant and it might be caused by hatching failure. Hatching is the process of releasing embryo from zona pellucida. If this process does not occur, it will cause pregnancy failure. Assisted hatching is a mechanism that dealing with thinning, slicing or artificially making holes in the zona pellucida to improve hatching. The process can be applied both in fresh or frozen embryos. This review describes various methods in assisted hatching such as enzymatic, chemical, mechanical, and laser beam as well as their advantages and disadvantages. Generally, some researches show that the technology of assisted hatching can improve the percentage of hatching and implantation of the embryo. However, in spite of the benefits, there are such weaknesses find in the zona pellucida of the embryo that has been manipulated such as toxic hazard medium, the risk of damage to the blastomeres or monozygotic twinning. Therefore, it is advisable to perform assisted hatching in certain cases that tends to face obstacles during the process of hatching such factors as age, embryo quality, the thickness of the zona pellucida and the number of failures in the <em>in vitro</em> fertilization program.