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Published in Ken Addley, MCQs, MEQs and OSPEs in Occupational Medicine, 2023
Polyvinyl chloride (PVC or vinyl) is a high strength thermoplastic material widely used in applications, such as pipes, medical devices, wire and cable insulation. It is the world’s third-most widely produced synthetic plastic polymer.
Chemosensory Disorders and Nutrition
Published in Alan R. Hirsch, Nutrition and Sensation, 2023
Carl M. Wahlstrom, Alan R. Hirsch, Bradley W. Whitman
Firefighters are exposed to high levels of olfactotoxins, with risk of synergy, formed during pyrolysis (application of heat to cause chemical decomposition). Combustion of wood alone produces as many as 200 toxic chemicals. Hydrogen sulfide, for example, has been demonstrated to induce olfactory loss. Oxidation of such materials as diesel fuel and fabrics produces a mixture of nitrogen oxides, including nitrogen tetroxide, acute exposures of which are olfactotoxic at low levels. Thermal degradation of polyvinyl chloride produces at least 75 toxic chemicals including the olfactotoxin chlorine. Other common olfactotoxins produced during combustion include: acrolein (from wood, at levels exceeding 3 ppm), ammonia (from household furnishings), halogen acid gases (from flame-retardant materials), isocyanates (from urethane isocyanate polymers), phosgene (from solvents), sulphur dioxide (at levels as high as 42 ppm), carbon monoxide (which ranges from 11 to 1087 ppm in fires), hydrogen cyanide (from paper and clothing, at levels up to 75 ppm), and heavy metals including cadmium, chromium, lead and zinc.
Management of Natural Rubber Glove Sensitivity
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
In the case of type IV hypersensitivity to NRL gloves, the use of nitrile or chloroprene gloves is not sufficient for prevention because these gloves may contain rubber accelerators or antioxidants, too. These patients should prefer gloves without any vulcanization process during manufacturing such as polyvinyl chloride (PVC) or polyurethane or styrene-based copolymer gloves.55 A recently updated list of accelerator-free gloves was given in Table 16.6.
Does the environment affect menopause? A review of the effects of endocrine disrupting chemicals on menopause
Published in Climacteric, 2023
Although rapidly metabolized and excreted, phthalates are ubiquitous in our environment and humans are continually exposed throughout life [12]. Phthalates are commonly used in polyvinyl chloride (PVC) plastics; however they are not chemically bound to PVCs, and therefore easily leach out of plastics and into surrounding air, food or other materials [13]. Phthalates can be found in building materials, furniture, clothing, cosmetics, pharmaceuticals, medical devices, dentures, children’s toys, food packaging, automobiles, cleaning materials and insecticides [13]. Low molecular weight phthalates tend to be used in cosmetics and can be dermally absorbed, while high molecular weight phthalates are used to make plastics flexible [13]. There are numerous phthalates in use; di-2-ethylhexyl phthalate (DEHP) is one of the older and therefore best-studied compounds, while less is known about the newer compounds such as 1,2-cyclohexane dicarboxylic acid di-isononyl ester (DINCH), di-iso-nonyl phthalate (DINP) and di-2-ethylhexyl terephthalate (DEHTP) [14]. Of the EDCs, the phthalate class has been most studied in its relationship with menopause.
Development of syringes and vials for delivery of biologics: current challenges and innovative solutions
Published in Expert Opinion on Drug Delivery, 2021
Saki Yoneda, Tetsuo Torisu, Susumu Uchiyama
The use of syringes started circa 1850 [5] for the injection of morphine solution stored in vials/ampoules into patients; however, syringes were not used as containers at that time. Prefilled syringes (PFS) in which drug substance solutions are filled and stored are relatively new dosage forms. In the 1980s, an insulin PFS was developed and launched in the market [6]. Since then, the use of PFS has been increasing due to its user-friendly nature and other advantages including reduced contamination risk and inconvenience for users. In recent years, the development of PFS has been accelerated for those requiring self-injection, such as patients with rheumatoid disorders and diabetes. Besides vials and PFS, polyvinyl chloride (PVC) bags can be used as a container for biologics. A previous study demonstrated that mAb formulations can be stored in PVC bags with high stability [7]. Cryobags made using ethylene-vinyl acetate are used as containers for recently approved cell therapy (ex-vivo gene therapy) drug products, such as KYMRIAHTM or YESCARTA® (stored under liquid nitrogen vapor phase) [8,9]. For in vivo gene therapy products using a viral vector, glass and cycloolefin polymer (COP) vials are used for the cryostorage (storage −35°C ~ −15°C, or under −65°C) [10–12].
The effect of preconceptional exposure of F0 male mice to di(2-ethylhexyl)phthalate on the induction of reproductive toxicity in F2 generation
Published in Drug and Chemical Toxicology, 2019
Małgorzata M. Dobrzyńska, Ewa J. Tyrkiel
Phthalate esters (esters of 1,2 benzenedicarboxylic acid) are used mainly to confer flexibility and transparency of plastics. They are found in a wide range of consumer products, like food packing and personal care products, medical devices and pharmaceuticals. They are used to soften a wide range of plastics, including medical products such as polyvinyl chloride (PVC) blood products and intravenous bags as well as dialysate bags and tubing (ATSDR 2000, 2001). Phthalates are highly susceptible to leaching into the environment because they are not linked covalently to the plastics. Human exposure to phthalates can occur also via inhalation and dermal routes and intravenous and parenteral absorption in patients undergoing medical procedures that involve the use of medical devices containing phthalates (ATSDR 2000, Hauser et al. 2004). The most often route of exposure to phthalates is consumption of food containing residuals of phthalates especially fatty foods, e.g. milk, butter and meats and drinking contaminated water (US EPA 1999).