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Lifestyle and Diet
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Mothballs are sold as small white balls containing 99.9% either of naphthalene or paradichlorobenzene (PDCB), both of which become a gas with pungent odor when exposed to air. Mothballs are used to repel moths in clothing and stored carpets and to keep pests out of the house (170). The majority of exposure to naphthalene in the environment occurs through inhalation, while other pathways such as dermal contact and ingestion are rare. Naphthalene is recently classified as a possible human carcinogen (171–172). Naphthalene exposure can cause hemolytic anemia due to destruction of red blood cells with apparition of jaundice and pallor. It is also neurotoxic. Small children may eat mothballs, thinking them candy (170). Para-dichlorobenzene (PDCB) is another ingredient of mothballs used as deodorizers and fumigants. PDCB toxicity can affect liver, kidneys, skin, lungs, and the central nervous system (CNS). Chronic toxicity of PDCB often results in leukoencephalopathy, ataxia, and heterogeneous neurological manifestations (173–175). Mothballs containing either PDCB or naphthalene, can cause cancer in animals, and are potential human carcinogens (170–172). So, be careful when using mothballs as moth or pest repellents. Due to the toxicity of naphthalene and para-dichlorobenzene, avoid the use of mothballs if you have a chronic disease, or infants and children in the house. Replace mothballs by cedar chips (170).
Outdoor Emissions
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
The main components of crude oil are aliphatic and aromatic hydrocarbons. Lower-molecular-weight aromatics, such as benzene, toluene, and xylene, are VOCs and evaporate within hours after the oil reaches the surface. VOCs can cause respiratory irritation and CNS depression. Benzene is known to cause leukemia in humans, and toluene is a recognized teratogen at high doses. Higher-molecular-weight chemicals such as naphthalene evaporate more slowly. Naphthalene is “reasonably anticipated to cause cancer in humans” based on olfactory neuroblastomas, nasal tumors, and lung cancers in animals. Oil can also release hydrogen sulfide gas and contains traces of heavy metals, as well as nonvolatile PAHs that can contaminate the food chain. Hydrogen sulfide gas is neurotoxic and has been linked to both acute and chronic CNS effects; PAHs include mutagens and probably carcinogens. Burning oil generates PM, which is associated with cardiac and respiratory symptoms and premature mortality. The Gulf oil spill is unique because of the large-scale use of dispersants to break up the oil slick. By late July, more than 1.8 million gallons of dispersant had been applied in the Gulf. Dispersants contain detergents, surfactants, and petroleum distillates, including respiratory irritants such as 2,1-butoxyethanol, propylene glycol, and sulfonic acid salts. In addition to oil and its products (Chapter 6), these dispersants cause havoc with the chemically sensitive, causing an exacerbation of their symptoms (Figures 1.10 and 1.11).
Special Senses
Published in Pritam S. Sahota, James A. Popp, Jerry F. Hardisty, Chirukandath Gopinath, Page R. Bouchard, Toxicologic Pathology, 2018
Kenneth A. Schafer, Oliver C. Turner, Richard A. Altschuler
Among the laboratory animal species, lenticular opacities are most frequent in rodents but can occur in any species (Balazs et al. 1970; Bellhorn 1973, 1974; Geiss and Yoshitomi 1999; Heywood 1973; Heywood et al. 1976; Loget 1995; Mukaratirwa et al. 2015; Taradach and Greaves 1984). Many compounds can cause cataract formation in animals (Grant 1986; Render and Carlton 1991c; Whiteley and Peiffer 2002). Some factors contributing to cataractogenesis include aging, disrupted metabolism, nutritional deficiency, exposure to oxygen radicals, x-rays, microwaves, gamma radiation, and UVA or UVB light (Gehring 1971; Grant 1986; Peiffer 1991a; Render and Carlton 1991b; Wegener 1995). Cataractogenesis associated with aging is thought to be the net result of oxidative stress (Geiss and Yoshitomi 1999; Taylor et al. 1995; Wegener 1995). Cataract may result from high concentrations of galactose, xylose, or glucose within the lens (Grant 1986; Turton and Hooson 1998). These sugars are converted to sugar alcohols that become trapped in the lens, accumulate, and result in osmotic swelling. Cataract may be produced after administration of various compounds (e.g., alloxan or streptozotocin) by a variety of mechanisms (Gajdosík et al. 1999; Geiss and Yoshitomi 1999; Grant 1986; Rubin 1974; Turton and Hooson 1998). Drugs, such as acetaminophen, cause cataract through oxidative stress mechanisms. Buthionine sulfoximine causes osmotic swelling of lenticular fibers. Naphthalene causes an inhibition of enzymes or disruption in protein metabolism. Compounds such as triparanol cause disruption of lipid metabolism and compounds such as busulfan produce radiomimetic cataracts. There may not always be a correlation between findings in animals and those in humans. Administration of some compounds, such as glucocorticoids, cause cataract in humans, but this is difficult to replicate in animals.
The association between urinary polycyclic aromatic hydrocarbon metabolites and atopic triad by age and body weight in the US population
Published in Journal of Dermatological Treatment, 2022
Sooyoung Kim, Kathryn A. Carson, Anna L. Chien
1-NAP comprises the largest proportion of all PAH metabolites. Naphthalene metabolizes to 1-NAP which is commonly emitted from household products such as deodorizers, insecticides, and carpeting as well as cigarette smoke, vehicle exhaust, and fireplaces (17). Moreover, naphthalene is classified as a class 2B carcinogen by the International Agency for Research on Cancer (17). We found that 1-NAP increased the risk of wheezing in children and adults as well as increased the risk of sneezing in children. The associations of 1-NAP on wheezing and sneezing, especially in children, imply non-occupational exposure to naphthalene in daily life. Naphthalene exposure occurs almost exclusively by inhalation, with approximately 2% in the particulate phase serving as a surrogate marker of air pollution (18). Careful investigation of daily life exposure (i.e. secondhand smoke) to naphthalene, especially in children, is warranted.
Design, synthesis and biological evaluation of novel thiazole-naphthalene derivatives as potential anticancer agents and tubulin polymerisation inhibitors
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Guangcheng Wang, Wenjing Liu, Meiyan Fan, Min He, Yongjun Li, Zhiyun Peng
On the other hand, naphthalene is a prominent core structure in many anticancer agents. A number of naphthalene derivatives have been reported as potent inhibitors of tubulin (Figure 1, V–VIII)22–25. Such as Maya et al. reported the synthesis of a series of new naphthalene analogues of combretastatin A-4 (CA-4) and the most cytotoxic naphthalene analogues V exerted tubulin polymerisation inhibition activity and arrest cell cycle in G2/M phase in human cancer cells25. Based on the lead compound HMNC-74, we synthesised a series of new naphthalene-chalcone derivatives and evaluated their anticancer activity. Among them, compound IV was the most potent tubulin polymerisation inhibitor with an IC50 value of 8.4 μM23. Recently, we have also reported a new series of benzophenone derivatives bearing naphthalene moiety, and compound VII displayed potent antiproliferative activity against various cancer cell lines by targeting tubulin colchicine binding site24. Furthermore, we also designed a new series of chalcones containing naphthalene moiety (VIII) based on natural tubulin inhibitor millepachine22,26.
Scaffold hopping and optimisation of 3’,4’-dihydroxyphenyl- containing thienopyrimidinones: synthesis of quinazolinone derivatives as novel allosteric inhibitors of HIV-1 reverse transcriptase-associated ribonuclease H
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Graziella Tocco, Francesca Esposito, Pierluigi Caboni, Antonio Laus, John A. Beutler, Jennifer A. Wilson, Angela Corona, Stuart F. J. Le Grice, Enzo Tramontano
Synthesis of 4-(naphthalen-2-yl)benzene-1,2-diol (23). To a mixture of 2-naphtylboronic acid (5.81 mmol), K2CO3 (5.81 mmol), and Pd(OAc)2 (0.048 mmol) in ethanol (15 ml) and water (5 ml) was slowly added 4-bromo-1,2-dimethoxybenzene (4.84 mmol). The mixture was stirred at room temperature for 18 h. To the resulting mixture was added water (80 ml), and then extracted with dichloromethane. The organic phase was separated, dried over Mg2SO4 and concentrated under reduced pressure to give a solid residue which was purified by flash chromatography (silica gel, hexane/ethyl acetate 5/1). The pure 2–(3,4-dimethoxyphenyl)naphthalene was obtained as white solid and used for the next reaction. Yield (%) = 93. 1H NMR (500 MHz, DMSO): δ 8.29 (d, J = 8.0 Hz, 1H), 8.12 (d, J = 8.0 Hz, 1H), 7.98 (d, J = 7.4 Hz, 1H), 7.82 (t, J = 8.0 Hz, 1H), 7.75 (t, J = 8.0 Hz, 1H), 7.61 (s, 1H), 7.45 (d, J = 8.2 Hz, 1H), 7.39 (d, J = 7.4 Hz, 1H), 7.12 (s, 1H), 7.02 (d, J = 8.2 Hz, 1H), 3.85 (s, 3H), 3.78 (s, 3H) ppm. 13 C NMR (500 MHz, DMSO): δ 151.20, 148.19, 139.45, 135.45, 132.13, 127.00, 124.15, 119.32, 117.56, 116.03, 113.40, 112.26, 110.67, 108.65, 57.23 ppm. HRMS calculated for C18H16O2 264.12 found 264.12.