Phthalates
Dongyou Liu in Handbook of Foodborne Diseases, 2018
Plastics are ubiquitous in modern technologies and consumer products. Global production of plastics exceeds 300 million tons annually. Polyvinyl chloride (PVC) plastics are rigid and brittle polymers. Plasticizers are materials added to PVC plastics in order to increase the flexibility, fluidity, pliability, elasticity, and/or toughness of the plastics through internal modification of the polymer constituents of the plastics. Phthalate esters (the diesters of phthalic acid) are the most commonly used plasticizers in North America with over 25 different phthalate esters currently used in commercial products. Phthalates are not covalently bound to the polymer matrix of plastics, which makes them highly susceptible to leaching. Phthalates are found in a wide variety of common products, including paints, medical devices, lotion, and perfume; thus, human exposure to phthalates is widespread.
Chemosensory Disorders and Nutrition
Alan R. Hirsch in Nutrition and Sensation, 2023
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.
Risk Factors for Allergies and Asthma
Pudupakkam K Vedanthan, Harold S Nelson, Shripad N Agashe, PA Mahesh, Rohit Katial in Textbook of Allergy for the Clinician, 2021
Children ages 6 months to 3 years with asthma in an emergency department were shown to have been exposed in their home to higher levels of volatile organic compounds than matched controls (Rumchev et al. 2004). Adults who had had indoor surfaces painted within the past 12 months more often reported asthma symptoms (OR 1.5) (Wieslander et al. 1997). Longitudinal studies showed an association between the presence of polyvinyl chloride surface materials in the home and an increased risk of asthma (OR 1.45) (Castro-Rodriguez et al. 2016). Among adolescents the prevalence of current asthma and allergic sensitization significantly increased with the lifetime number of hours spend in outdoor swimming pools (Bernard et al. 2008).
Human urinary concentrations of monoisononyl phthalate estimated using physiologically based pharmacokinetic modeling and experimental pharmacokinetics in humanized-liver mice orally administered with diisononyl phthalate
Published in Xenobiotica, 2019
Tomonori Miura, Hiroshi Suemizu, Masatomo Goto, Norifumi Sakai, Hiroshi Iwata, Makiko Shimizu, Hiroshi Yamazaki
The biomonitoring of human fluids using high-technology techniques to determine the levels of various chemicals is valuable for quantitatively evaluating human exposure. The phthalates di(2-ethylhexyl) phthalate (DEHP, Figure 1(A)) and diisononyl phthalate (DINP, Figure 1(B)) are used as plasticizers in the production of polyvinyl chloride and exhibit low toxicity from common levels of exposure (Hellwig et al., 1997; Koch et al., 2006). Primary and/or secondary phthalate monoester metabolites of DEHP and DINP (Figure 1) have been detected in human urine samples (Herr et al., 2009; Koch et al., 2017; Zeman et al., 2013). DEHP and DINP are reportedly rapidly hydrolyzed to mono(2-ethylhexyl) phthalate (MEHP, Figure 1(A)) and monoisononyl phthalate (MINP, Figure 1(B)), respectively, in human intestinal and liver microsomal/cytosolic fractions (Choi et al., 2012; Hsu et al., 2016). Although no information is available on the antiandrogenic effects of DEHP or DINP in humans, animal studies have reported that oral exposure to high doses has resulted in developmental or reproductive effects in rodents (Hellwig et al., 1997; Kluwe et al., 1983). Different in vivo metabolic profiles of MEHP in rats, marmosets, and humans have been reported (Kurata et al., 2012a,b; Rhodes et al., 1986), with no significant toxicological effects evident in animals for doses in the range 100–2000 mg DEHP/kg body weight. The pharmacokinetics of DEHP in humanized-liver mice indicated that human hepatocytes transplanted into mice could mediate rapid excretion of primary and secondary metabolites of DEHP into the urine (Adachi et al., 2015).
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.
Predictability of human pharmacokinetics of diisononyl phthalate (DINP) using chimeric mice with humanized liver
Published in Xenobiotica, 2019
Hiroshi Iwata, Masatomo Goto, Norifumi Sakai, Hiroshi Suemizu, Hiroshi Yamazaki
Phthalate esters, which are synthesized by reacting o-phthalic anhydride and alcohols, are used as plasticizers in preparing polyvinyl chloride polymers and rubber, among others (Wormuth et al., 2006). Typical phthalate plasticizers include di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP) and diisononyl phthalate (DINP). They are selected for specific applications depending on the carbon number of the alcohol and the degree of branching (Koch et al., 2006). Unlike DEHP and DBP which are single pure compounds, commercial DINP is composed of a complex mixture containing C8–C10 (C9 rich) branched chain dialkyl phthalate isomers (Hellwig et al., 1997). In recent years, DEHP has been replaced with DINP as the new major plasticizer for polyvinylchloride polymers. DINP comes in two forms, depending on the composition of the isononyl alcohol moieties: DINP-1 (CAS 68515-48-0) and DINP-2 (CAS 28553-12-0).
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