Search Results (4)

The inhalation of gasoline vapors (GV) is associated with developing various pathologies. Particularly, oil refinery and gas station workers are at a greater risk of developing lung cancer, kidney cancer, bladder cancer, and hematological disorders, including acute myeloid leukemia. Therefore, preventing the harmful effects of GV and alleviating their consequences appear to be important and timely issues. In this study, we investigated the potential of vitamin D₃, turmeric powder, and their combination to ameliorate the toxicity of gasoline fumes in rats. Separate groups of animals fed with a standard rodent diet, with or without the supplementation of vitamin D₃ (750 IU/kg body weight) and/or turmeric powder (0.5%, w/w, in food), were untreated or treated with GV (11.5 ± 1.3 cm³/h/m³/day) for 30, 60, or 90 days. Changes in the body weight were monitored weekly. Histological, biochemical, and hematological parameters were determined at the end of each treatment period. While the exposure of rats to GV resulted in a time-dependent reduction in body weight, supplementation with vitamin D₃, but not with turmeric root powder or their combination, partially prevented weight loss. Macroscopical and histological analyses showed pronounced time-dependent changes in the organs and tissues of GV-treated rats. These included alveolar wall collapse in the lungs, the destruction of the lobular structure and hepatocytolysis in the liver, the shrinkage and fragmentation of glomeruli in the kidneys, and the disorganization of the lymphoid follicles in the spleen. However, co-treatment with the nutritional supplements tested, especially vitamin D₃, noticeably alleviated the above conditions. This was accompanied by a significant improvement in the blood chemistry and hematological parameters. Collectively, our results demonstrate that the harmful effects of environmental exposure to GV can be reduced upon supplementation of vitamin D₃. The fact that the protective activity of vitamin D₃ alone was higher than that of turmeric root powder or the combined treatment suggests that combinations of these supplements may not always be more beneficial than each agent applied separately. Full article

Binary gas mixture of N₂ and trans-1,1,1,4,4,4-hexafluorobut-2-ene (HFO4E) is presented as an alternative to SF6 in medium-voltage electrical equipment. Its stability was tested under different conditions. No change was observed in the gas mixture after a permanent AC voltage of 30 kV applied for two years or during the making operations with a standard load-break switch. The same behavior was obtained under dielectric tests, electrical arcs and temperature rise tests according to the IEC 62271-1:2011 standard. For all of these conditions, the concentration of HFO4E remains practically unchanged; there is no impact on the insulation properties of the system and the degradation products formed would not affect the health and the environment if there were leaks. In these studies, gas mixtures samples were analyzed by a validated methodology based on gas chromatography coupled to mass spectrometry and thermal conductivity detectors. Finally, an OECD TG 403 acute inhalation toxicity test was also carried out with the gas mixture aged after the mentioned making operations. None of the mice used in the toxicity test were affected after 4 h of exposition to an ambient air with 30,000 ppmv of the gas mixture. Full article

It has been proven that the gas trifluoromethanesulfonyl fluoride (CF₃SO₂F) has good dielectric performance and the potential to replace the potent greenhouse gas sulfur hexafluoride (SF₆), which is the most commonly used insulating gas in high-voltage electrical equipment. However, there are many key biochemical properties, such as toxicity, that the new eco-friendly insulating gas will need to obtain. It could protect the operator and equipment and help the chemical engineering development of this gas in the power grid industry. In this study, according to Horn’s method, an acute toxic gas inhalation test was carried out. The results showed that the lethal concentration of 50% (LC50) for female rats was 27.1 g/m³, and that for male rats was 23.3 g/m³. The behavioral and vital sign changes in the rats were recorded. Pathological sections of the main organs revealed that the heart, lungs, spleen, and eyes suffered the most damage from the gas. This research also provides scientific suggestions for the protection of electrical workers exposed to the insulating gas CF₃SO₂F. Full article

Acute releases of hydrogen sulfide (H₂S) are of serious concern in agriculture, especially when farmers agitate manure to empty storage pits before land application. Agitation can cause the release of dangerously high H₂S concentrations, resulting in human and animal fatalities. To date, there is no proven technology to mitigate these short-term releases of toxic gas from manure. In our previous research, we have shown that biochar, a highly porous carbonaceous material, can float on manure and mitigate gaseous emissions over extended periods (days–weeks). In this research, we aim to test the hypothesis that biochar can mitigate H₂S emissions over short periods (minutes–hours) during and shortly after manure agitation. The objective was to conduct proof-of-the-concept experiments simulating the treatment of agitated manure. Two biochars, highly alkaline and porous (HAP, pH 9.2) made from corn stover and red oak (RO, pH 7.5), were tested. Three scenarios (setups): Control (no biochar), 6 mm, and 12 mm thick layers of biochar were surficially-applied to the manure. Each setup experienced 3 min of manure agitation. Real-time concentrations of H₂S were measured immediately before, during, and after agitation until the concentration returned to the initial state. The results were compared with those of the Control using the following three metrics: (1) the maximum (peak) flux, (2) total emission from the start of agitation until the concentration stabilized, and (3) the total emission during the 3 min of agitation. The Gompertz’s model for determination of the cumulative H₂S emission kinetics was developed. Here, 12 mm HAP biochar treatment reduced the peak (1) by 42.5% (p = 0.125), reduced overall total emission (2) by 17.9% (p = 0.290), and significantly reduced the total emission during 3 min agitation (3) by 70.4%. Further, 6 mm HAP treatment reduced the peak (1) by 60.6%, and significantly reduced overall (2) and 3 min agitation’s (3) total emission by 64.4% and 66.6%, respectively. Moreover, 12 mm RO biochar treatment reduced the peak (1) by 23.6%, and significantly reduced overall (2) and 3 min total (3) emission by 39.3% and 62.4%, respectively. Finally, 6 mm RO treatment significantly reduced the peak (1) by 63%, overall total emission (2) by 84.7%, and total emission during 3 min agitation (3) by 67.4%. Biochar treatments have the potential to reduce the risk of inhalation exposure to H₂S. Both 6 and 12 mm biochar treatments reduced the peak H₂S concentrations below the General Industrial Peak Limit (OSHA PEL, 50 ppm). The 6 mm biochar treatments reduced the H₂S concentrations below the General Industry Ceiling Limit (OSHA PEL, 20 ppm). Research scaling up to larger manure volumes and longer agitation is warranted. Full article