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Diversity of Mechanisms for Boron Toxicity in Mammals
Published in Debasis Bagchi, Manashi Bagchi, Metal Toxicology Handbook, 2020
Diana Rodríguez-Vera, Antonio Abad-García, Mónica Barrón-González, Julia J. Segura-Uribe, Eunice D. Farfán-García, Marvin A. Soriano-Ursúa
The average concentrations of boron and the most common BCCs to which mammals are exposed should be considered. On the one hand, the abundance of boron and BCCs in the Earth’s crust is around 10 mg/kg (from 5 mg/kg in basalts to 100 mg/kg in shales) and about 4.5 mg/L in the oceans. Surface water levels range from 0.01 to 2 mg/L. On the other hand, borax pentahydrate, borax, sodium perborate, boric acid, colemanite, and ulexite are recognized as the most important commercial BCCs (Ocampo-Néstor et al. 2017). Moreover, sugar-borate esters are common compounds found in vegetables (Hunter et al. 2019). Mammal exposures to boron, generally as boric acid or borates, may occur through food and water ingestion or food contamination with pesticides containing BCCs, as well as by inhalation of boron-containing dust or powders, or BCCs from cosmetics or pharmaceutical preparations. Conversely, the most common inorganic BCCs, boric acid and borax (sodium tetraborates), are used in industrial and medical applications (Soriano-Ursúa, Farfán-García, and Geninatti-Crich 2019). Therefore, BCCs toxicity from natural sources in mammals is not easily identified.
Recent Advances in Boron-Based Flame Retardants
Published in Yuan Hu, Xin Wang, Flame Retardant Polymeric Materials, 2019
Borates have been commercially successful in both plastics and rubbers. The fire test performance of borates can be enhanced with the use of co-additives such as metal hydroxides, and N-, P-, and Si-containing compounds. Borates alone can also function as flame retardant in char-forming polymers such as polyethersulfone, polyimide, etc.
Inorganic Chemicals in Drinking Water
Published in Joseph Cotruvo, Drinking Water Quality and Contaminants Guidebook, 2019
Boron is suspected to be a trace nutrient in humans. Accidental poisoning has been reported in infants with resulting mild diarrhea and vomiting. The half-life after ingestion in infants is about 8 hours. In adults, the lowest adverse effect level was estimated to be 9.6 mg/kg/day as boron (>672 mg/day) in one study for a 70-kg adult. Acute oral exposure symptoms occurred from 3.68 to 70 mg/kg/day as boron. Long-term exposures in patients being treated ranged as high as 24.8 mg/kg/day as boron. One patient at 5 mg/kg/day as boron for 15 days reported indigestion, anorexia, and dermatitis. The symptoms disappeared when the dose was reduced to 2.5 mg/kg/day. Reproductive studies of residents and workers with high boron exposures did not detect adverse effects. Borate compounds are not mutagenic and they are not considered to be carcinogenic. Some animal studies have shown some reproductive and developmental effects from high-dose exposures of borates.
Controllable synthesis of 0D, 1D, and 2D nano lanthanum borates and their dispersion stabilities and tribological properties in rapeseed oil
Published in Journal of Dispersion Science and Technology, 2023
Kecheng Gu, Qiaoyu Gan, Wang Lin, Xiuli Zuo, Junyu Liu, Jian Wang, Keyu Lin, Hao Yan, Zeqi Jiang
Thanks to their special physical and chemical properties, nano additives have been widely employed as a kind of effective lubricating additive, which included nano metals, nano calcium borate, nano lanthanum borate, nano lanthanum fluoride, graphene.[9–15] It is worth to mention that inorganic borates possess excellent oxidation stability, corrosion resistance, and would not bring toxicity and/or pollution to the environment and ecology.[16,17] Thus, B-type additive would be a potential candidate to be employed as a lubricating additive with multi comprehensive performance. However, the drawback of poor immiscibility of B-type additives in hydrocarbon oils remains to be overcame. Also as confirmed by previous works, rare earth elements exhibited some special characteristics including good chemical activity, low electronegativity, and strong adsorption ability that could facilitate the aggregation of rare earth elements on the rubbing surfaces.[18]