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Marine Litter Plastics and Microplastics and Their Toxic Chemicals Components
Published in Leo M. L. Nollet, Khwaja Salahuddin Siddiqi, Analysis of Nanoplastics and Microplastics in Food, 2020
Frederic Gallo, Cristina Fossi, Roland Weber, David Santillo, Joao Sousa, Imogen Ingram, Angel Nadal, Dolores Romano
Some of those intentional chemical additives in plastics with toxic and endocrine-disrupting properties might be present at levels of 1000–500,000 mg/kg (ppm). This is the case of polybrominated diphenyl ethers (PBDEs) used as flame retardants in plastics, polyurethane foams and textiles; tetrabromobisphenol A (TBBPA)† [40], used as flame retardant in epoxy, vinyl esters and polycarbonate resins; or hexabromocyclododecane (HBCDD), used in polystyrene foam (EPS/XPS) or di-2-ethylhexyl phthalate (DEHP) in PVC. It is also recognized that such chemicals can be found as particularly prominent contaminants in marine species collected from areas in which flame retardant-treated plastics are in use. For example, elevated HBCDD levels were found in oysters from aquaculture farms at which EPS/XPS buoys containing HBCDD were present [46]. The observation that high levels of the y-HBCDD isomer, which dominates commercial mixtures of this flame retardant [47,48], can be detected in fish in some European waters [49] indicates that direct exposure to technical HBCDD present in the polymer matrix can also be a relevant exposure pathway for fish, as well as the wider environmental exposure to the more stable α-HBCDD.
Resins
Published in Martin W. Jawitz, Michael J. Jawitz, Materials for Rigid and Flexible Printed Wiring Boards, 2018
Martin W. Jawitz, Michael J. Jawitz
To generate an epoxy resin system suitable for impregnation, the base monomer is either further reacted with additional bisphenol-A to yield a non-fire-retardant resin or reacted with tetrabromobisphenol-A to yield a flame-retardant resin (Figure 2.2). The bromine content of these resins is approximately 18 to 21% weight. At this percentage, the resin should meet the flammability requirements of UL 94 V-O without further additives. The brominated resin consists of bromine bonded to the epoxy molecule in such a manner that no free bromine is present. The major disadvantage of this type of resin is poorer adhesion between the epoxy and copper foil, which leads to lower copper peel strength and poorer adhesion of the copper in the plated through holes. Difunctional resins have adequate properties especially for simple single- and double-sided circuit applications, but in general these systems are not adequate for higher-layer-count multilayer boards or the more critical double-sided boards, due to a low Tg leading to a high z-axis expansion, low chemical resistance, and a higher moisture absorption. These properties can be improved by adding more cross-linking to the system.
Industrial Polymers
Published in Manas Chanda, Plastics Technology Handbook, 2017
Known for many years, epoxy oligomers made from tetrabromobisphenol A are still used as the flame retardant in polycarbonates because they minimally affect the heat distortion temperature and even show a positive effect on impact strength. About 6–9 wt% of the epoxy oligomer is required for achieving V-0 rating and a thermotropic liquid crystal polyester helps to improve melt flow, so that thin-walled parts can be molded [38]. Antimony trioxide is not normally used in combination with halogen-containing additives in PC, because it causes loss of clarity.
Apigenin attenuates tetrabromobisphenol A-induced cytotoxicity in neuronal SK-N-MC cells
Published in Journal of Environmental Science and Health, Part A, 2023
Eun Mi Choi, So Young Park, Kwang Sik Suh, Suk Chon
Tetrabromobisphenol A (2,2′6,6′-tetrabromo-4,4′-isopropyl-idenediphenol; TBBPA) is a reactive brominated flame retardant widely used in various industrial and household products.[1] TBBPA has been detected in cow and human milk, serum, adipose tissue, and umbilical cord serum.[2,3] Continuous TBBPA uptake may increase its concentration and potentiate its toxicological effects.[4] TBBPA can increase developmental toxicity, oxidative stress, and apoptosis and influence antioxidant defense systems.[5] Our previous study reported that TBBPA causes oxidative damage and triggers mitochondrial dysfunction in mouse osteoblastic MC3T3-E1 cells,[6] rat pancreatic β-cells,[7] and mouse osteoclasts.[8] TBBPA disturbs Ca homeostasis and induces oxidative stress in neuronal cell lines.[9,10] TBBPA enhances apoptosis and lactate dehydrogenase (LDH) release in mouse cortical neurons.[11] Apoptosis of neural stem cell by TBBPA was accompanied by increased reactive oxygen species (ROS) generation and mitochondrial dysfunction.[12] TBBPA initiates oxidative stress, which leads to activate mitochondrial apoptosis and Nrf2 pathway in human hepatocytes.[13]
Microplastics pollution in Bangladesh: current scenario and future research perspective
Published in Chemistry and Ecology, 2020
Md. Ekramul Karim, Sohana Al Sanjee, Shohel Mahmud, Modhusudon Shaha, Md. Moniruzzaman, Keshob Chandra Das
Despite direct effect, microplastics are also reported to have some indirect effects on organisms when acting as a carrier for certain chemical pollutants as well as alien microbial communities. Plastics additives such as phthalates and flame retardants, and hydrophobic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), Polybrominated diphenyl ethers and heavy metals absorbed into the plastic particles may leach into organs of aquatic biota and can cause disruption in various immuno-modulatory functions, for example, endocrine disruption, delayed ovulation, and hepatic stress [60–62]. Tetrabromobisphenol A (TBBPA) – a flame retardant that is used in many different types of plastics such as those found in microcircuits, known to cause abnormalities in thyroid hormones, pituitary function, and infertility in lab rats [63].
The auxiliary effect of organic matter humic acids on the anaerobic biodegradation of tetrabromobisphenol A
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Mengjie Fan, Yue Zhou, Qiong Huang, Yingwen Chen, Haitao Xu, Shubao Shen
Tetrabromobisphenol A (TBBPA) is widely used in printed circuit boards, insulated wires, and polycarbonate plastics (Li et al. 2016a). However, the lipophilicity and high octanol/water partition coefficient give it a high durability in sediment and other anaerobic environments (Cheng and Hua 2018), which are potential threats to environment and human health. Many researchers have shown that TBBPA can induce cytotoxicity and hepatotoxicity due to its similarity in structure with thyroid hormone and estrogen agonists (Chu and Letcher 2013). Therefore, researchers pay great attention to study the degradation of TBBPA.