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Biological Fate of Nanoparticles
Published in C. Anandharamakrishnan, S. Parthasarathi, Food Nanotechnology, 2019
S. Parthasarathi, C. Anandharamakrishnan
Bioadhesion is a phenomenon by which two materials, one of which should be biological in nature, are held together by interfacial force for an extended period of time. If the adhesive attachment is to mucus or a mucous membrane, then the phenomenon is referred to as mucoadhesion (Smart, 2005; Gu et al., 1988). Mucous membranes are also called mucosae, and represent the moist surface of various body cavities, such as the gastrointestinal wall and respiratory tract. The molecular weight of mucins varies from 500 kDa to 20 MDa and the thickness of the mucus layer differs on different mucosal surfaces, 50 to 450 μm in the stomach, and >1 μm in the oral cavity. The composition of mucus gels includes mucin glycoproteins (usually termed mucins), lipids, inorganic salts, and water, the latter accounting for more than 95% of mucus weight, providing a highly hydrated system (Marriott and Gregory, 1990). Most of the mucins are negatively charged due to the presence of sialic acids and ester sulfates, and fully ionized at pH > 2.6 (Sogias et al., 2008).
An evaluation of occupant health and indoor environmental quality in university workspaces
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Carbon dioxide was associated with eye irritation, dryness and itching, and asthma in this study. Other research suggested that health symptoms associated with CO2 included headache, tiredness, eye symptoms, nose symptoms, respiratory tract symptoms, and total symptom results (Erdmann et al. 2002; Tsai, Lin, and Chan 2012). In the office environment, the primary source of CO2 is respiration from the building’s occupants (Apte, Fisk, and Daisey 2000; Hou et al. 2021; Mentese et al. 2020). Metabolic activity, combustion and motor vehicles in garages are emission resources of CO2 (Jones 1999; Yang et al. 2022). In a study by Seppanen, Fisk, and Mendell (1999), about one-half of 22 studies of SBS symptoms in office work environments showed that increased indoor CO2 levels were positively related to a significant increase in the prevalence of one or even more SBS symptoms. In other studies, CO2 concentrations were associated with increased prevalence of certain mucous membrane and SBS symptoms (Erdmann et al. 2002) as well as with eye irritation and nonspecific and upper respiratory symptoms (Tsai et al. 2012), and headache, fatigue, sleepiness, and affected cognitive performance and decision making ability (Shriram, Ramamurthy, and Ramakrishnan 2019; Zhang et al. 2017) A study by (de Oliveira, Rupp, and Ghisi 2021) demonstrated that a mixed-mode ventilation system is a good strategy for air quality satisfaction and energy savings to reduce CO2 concentrations.
Symptoms and oxylipins in plasma before and after exposure to rooms in which individuals have both experienced and not experienced building-related symptoms – an exploratory study
Published in International Journal of Environmental Health Research, 2022
Anna-Sara Claeson, Johan Sommar, Ingrid Liljelind
Participants with BRS were recruited (n = 51) from the same workplace: a hospital in Northern Sweden with known indoor environmental problems. Individuals with BRS sought medical care because of building-related symptoms between 2014 and 2017 and were examined by a physician. There was no other explanation for their symptoms than the indoor environment (i.e. reported diagnoses were attributed to other causes). The participants then answered a questionnaire that included questions about demographics and physician-based diagnoses, as well as questions about BRS-related symptoms they had experienced at their workplace during the last month, categorised as general symptoms (headache, head pressure, concentration difficulties, tiredness, nausea and dizziness/lightheadedness), mucous membrane symptoms (asthma/wheezing, coughing, throat irritation/hoarseness, dry throat, nasal congestion/discharge, excessive mucus production, nasal mucosa irritation/dryness, sneezing, eye irritation, dry eyes) and skin symptoms (facial itching/stinging/tightness/heat, facial redness, dry facial skin, body itching). The symptoms were rated on a scale that included the following response options: “Yes, every week,” “Yes, sometimes,” “No, never” (See Table 1). Symptoms have been listed by WHO as being of importance for building-related health issues (WHO 1983, 2000) and have been used in previous studies to identify cases of building-related intolerance (Edvardsson et al. 2008).
Measurements and health impacts of carbon black and BTEXs in photocopy centers
Published in Archives of Environmental & Occupational Health, 2018
Pattama Senthong, Sivasit Wittayasilp
To date, photocopiers and printers are normally used to copy and print paper in the university. A number of studies have shown that carbon black and several volatile organic compounds (VOCs) especially benzene, toluene, ethylbenzene, xylene and styrene (BTEXs) are emitted by the paper processed during copying and printing.1–6 These air pollutants can cause indoor air quality (IAQ) problems and link to sick building syndrome (SBS).7–9 Several studies have indicated that carbon black and BTEXs from photocopiers have potential health effect and can be associated with many characteristics of symptoms of human health such as headache, dizziness, nausea, mucous membrane irritation, chest pain, damage to the conjunctival epithelium and cancer.10–11 The International Agency for Research on Cancer (IARC) classified benzene as human carcinogen (Group 1) that can cause leukemia,12–13 and styrene and carbon black as possible human carcinogen (Group 2B).14 Toluene can affect the reproductive and the central nervous system.15 Ethylbenzene and xylene can cause respiratory and neurological effects.16–17 The Occupational Safety and Health Administration (OSHA) set a permissible exposure limits for BTEXs of 1, 200, 100, 100 and 100 ppm, respectively.18 National Institute for Occupational Safety and Health (NIOSH) is the most strict and recommend 0.1, 100, 100, 100 and 50 ppm for BTEXs, respectively.19 OSHA, NIOSH and British suggest carbon black level below 3.5 mg/m3 but Germany establish this value of 6 mg/m3.20–21