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Toxicology Studies of Semiconductor Nanomaterials: Environmental Applications
Published in Suresh C. Pillai, Yvonne Lang, Toxicity of Nanomaterials, 2019
T. P. Nisha, Meera Sathyan, M. K. Kavitha, Honey John
The nanoparticles show enhanced ROS generation compared to their bulk counterpart due to their large surface area, which provides more reactive sites for light absorption (Verma et al., 2018). Li et al. (2012b) demonstrated the ROS generation kinetics in seven different metal oxide nanoparticles and their bulk counter parts under UV irradiation. The quantitative measurement of ROS generation was performed using indicators. XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophehyl)-2H-tetrazolium-5-carboxanilide) can be used as an indicator for superoxide radical. p-Chlorobenzoic acid and furfuryl alcohol can be used as indicators for hydroxyl and singlet oxygen, respectively (Li et al., 2012a, 2012b). ZnO nanoparticles can induce cellular toxicity by ROS generation. TiO2 and ZnO generate three types of ROS, namely superoxide radical, hydroxyl radical, and singlet oxygen. Fe2O3 nanoparticles produce significant amounts of superoxide radical and minimal amounts of hydroxyl radical. SiO2 and Al2O3 nanoparticles generate singlet oxygen while CeO2 contributes superoxide radical. Also, ZnO and CuO exhibit toxicity due to the release of toxic ions during irradiation; the metal ion release from particles can be investigated using inductively coupled plasma-mass spectrometry (ICP-MS). Photochromic tungsten oxide nanoparticles show UV-induced toxicity against bacterial and mammalian cells. These nanoparticles show both time- and dose-dependent cytotoxicity due to the decreased dehydrogenase activity (Popov et al., 2018).
Formaldehyde
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Furfural is an important renewable, nonpetroleum-based, chemical feedstock. Hydrogenation of furfural provides furfuryl alcohol (FA), which is a useful chemical intermediate and which may be further hydrogenated to tetrahydrofurfuryl alcohol (THFA). THFA is used as a nonhazardous solvent in agricultural formulations and as an adjuvant to help herbicides penetrate the leaf structure. Furfural is used to make other furan chemicals, such as furoic acid via oxidation1 and furan itself via palladium-catalyzed vapor-phase decarbonylation2. Furfural is also an important chemical solvent.
Catalog of Herbs
Published in James A. Duke, Handbook of Medicinal Herbs, 2018
In humans, caffeine, 1,3,7-trimethylxanthine, is demethylated into three primary metabolites: theophylline, theobromine, and paraxanthine. Since the early part of the 20th century, theophylline has been used in therapeutics for bronchodilation, for acute ventricular failure, and for long-term control of bronchial asthma. According to Tiscornia et al.,116 the sterol fraction of coffee seed oil contains 45.4 to 56.6% sitosterol, 19.6 to 24.5% stigmasterol, 14.8 to 18.7% campesterol, 1.9 to 14.6% 5-avenasterol, 0.6 to 6.6% 7-stigmasterol, and traces of cholesterol and 7-avenasterol. Coffee pulp is a valuable cattle feed, unpalatable to cattle at first. The pulp is comparable to corn in total protein, and superior to it in calcium and phosphorus content. In India, cattle feed on the pulp with no apparent ill effects. The ash of the “cherry” husk is rich in potash and, therefore, forms a valuable manure. Air dry coffee pulp contains 1.34% N, 0.11% phosphoric acid (P2O5), and 1.5% potash (K2O). After compositing these values change to 0.91% N, 0.31% P2O5, 0.71% K2O.1 Leaves and reject seed may also be used as compost.1 Leaves are reported to contain, per 100 g, 300 calories, 6.4% water, 9.3% protein, 5.5 g fat, 66.6 g total carbohydrate, 17.5 g fiber, 12.2 g ash, 1910 mg Ca, 170 mg P, 96.6 mg Fe, 2360 mg carotene equivalent, 0.00 mg thiamine, 0.21 mg riboflavin, and 5.2 mg niacin. Seeds contain, per 100 g, 203 calories, 6.3% water, 11.7 g protein, 10.8 g fat, 68.2 g total carbohydrate, 22.9 g fiber, 3.0 g ash, 120 mg Ca, 178 mg P, 2.9 mg Fe, 20 mg β-carotene equivalent 0.22 mg thiamine, 0.6 mg riboflavin, and 1.3 mg niacin.21 Raw coffee contains circa 10% oil and wax extractable with petroleum ether. The fatty acids consist chiefly of linoleic, oleic, and palmitic acids, together with smaller amounts of myristic, stearic, and arachidic acids. From the unsaponifiable matter, a phytosterol, sitosterol, cafesterol, caffeol, and tocopherol have been isolated. Among the identified components of the volatile oil present in roasted coffee are acetaldehyde, furan, furfuraldehyde, furfuryl alcohol, pyridine, hydrogen sulphide, diacetyl, methyl mercaptan, furfuryl mercaptan, dimethyl sulfide, acetylpropionyl, acetic acid, guaiacol, vinyl guaiacol, pyrazine, w-methylpyrrole, and methyl carbinol. All these substances do not preexist in the unroasted coffee beans; some are, undoubtedly, the products of the roasting process and others are produced by the decomposition of the more complex precursors.1
The impact of filtered water-pipe smoke on healthy versus cancer cells and their neurodegenerative role on AMPA receptor
Published in Drug and Chemical Toxicology, 2022
Mohammed Hawash, Mohammad Qneibi, Nidal Jaradat, Murad Abualhasan, Johnny Amer, EL-Hamouz Amer, Tasneem Ibraheem, Siham Hindieh, Sama Tarazi, Shorooq Sobuh
The literature showed that gas chromatography-mass spectrometry (GC-MS) is primarily used in determining and extracting toxins of water-pipe smoke, such as 1-naphthylamine, 2-aminobiphenyl, 2-naphthylamine, 2-furaldehyde, 2-furoic acid, 2-furyl methyl ketone, 3,5-dichloroaniline, 4,4′-oxydianiline, p-chloroaniline, 5-methyl-2-furaldehyde, aniline, carbon monoxide, furfuryl alcohol, and 5-(hydroxymethyl)-2-furaldehyde (Shihadeh et al. 2015, Middha and Negi 2019). Our findings showed that no previous studies have tried to condense the smoke generated from the water pipe or used liquid chromatography-mass spectrometry (LC-MS) to detect the toxins that might accumulate in a smoker’s lungs after inhaling the emitted smoke. Therefore, in this study, we aim to detect new toxins from the water pipe through the aforementioned technique, define a new filtration system, and decrease the toxic compounds’ concentrations to reduce their cytotoxic and neurotoxic effects.
Human and organizational factors in Chinese hazardous chemical accidents: a case study of the ‘8.12’ Tianjin Port fire and explosion using the HFACS-HC
Published in International Journal of Occupational Safety and Ergonomics, 2018
Lin Zhou, Gui Fu, Yujingyang Xue
After the disaster, an accident investigation team was put together with the approval of China’s State Council, and the final accident inquiry report [27] was published on the SAWS website. As mentioned in the report, the initial fire was due to the spontaneous ignition of nitrocellulose (C12H16N4O18) in containers in the storage yard at Ruihai Company. Nitrocellulose is a highly flammable, explosive chemical material that can slowly decompose and generate heat at room temperature. When the temperature exceeds 40 °C, decomposition accelerates and heat accumulates, resulting in spontaneous ignition at 180 °C without dissipation. Manufacturers usually add ethanol and water to nitrocellulose as a wetting agent and manually package it into plastic bags that are further sealed with ropes. When the nitrocellulose containers were transported to and stored at Ruihai Company, they were moved and loaded roughly by the forklift drivers, breaking open the packages. The temperature in the containers on the day of accident was as high as 65 °C, which made the wetting agent volatile, causing the nitrocellulose to rapidly decompose. Because of the poor ventilation in containers, the heat accumulated and reached the spontaneous ignition temperature, sparking the initial fire. The fire spread and ignited chemicals (refined naphthalene, sodium sulfide, furfuryl alcohol, etc.) in nearby containers, accelerating the stored ammonium nitrate decomposition that eventually caused the first explosion at 23:34:06, the power of which was equivalent to 15 t of trinitrotoluene (TNT). Because of the spreading fire and the shock wave from the first explosion, containers with flammable solids, oxidizers and corrosives located about 20 m northwest of the first explosion exploded at 23:34:37 with a power equivalent to 430 t of TNT.