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Designing for Head and Neck Anatomy
Published in Karen L. LaBat, Karen S. Ryan, Human Body, 2019
Breath is essential to life and the air-flow pathways through the nose and mouth to the lungs need to be protected. Because small children tend to put things into their mouths and occasionally push objects into their nostrils, they are especially susceptible to choking. Choking can occur if an object or piece of food lodges at the back of the oral or nasal cavity, anywhere in the pharynx, or erroneously reaches the trachea. If a small garment element (a piece of trim or button) detaches with use and is small enough to enter the throat of a child, it becomes a choking hazard.
Chemical Terrorist Agents
Published in Robert A. Burke, Counter-Terrorism for Emergency Responders, 2017
Odors range from strong and stifling when concentrated, to the smell of freshly mowed hay in lower concentrations. Phosgene has a boiling point of 8.2°C (45.6°F) and is noncombustible. The vapor density is 3.4, which is heavier than air, and the specific gravity is 1.37 at 20°C, which is heavier than water. Phosgene will not undergo polymerization, but reacts with water, ammonia, and amines. When exposed to temperatures above 572°F, it decomposes to form carbon monoxide (CO) and chlorine. The primary route of exposure is through inhalation, by which it is very toxic. It is also a strong eye irritant and has a TLV of 0.1 ppm or 0.40 mg/mp3p in air. General population limits are 0.0025 mg/m3. In addition to mild conjunctival irritation, direct effects of exposure to phosgene result in damage to the lungs. The primary effect of exposure is pulmonary edema (fluid in the lungs). Death can occur in several hours after an exposure to a high concentration. Most fatalities, however, reach a maximum effect from the pulmonary edema in about 12 hours, and death occurs from 24 to 48 hours after exposure. Symptoms include coughing, choking (thus the term choking agent), tightness in the chest, nausea, and possibly vomiting, headache, and lacrimation. There is no real relationship between the symptoms and the prognosis. Treatment involves rest and warmth, oxygen therapy, systemic steroids (prednisone IV), and steroid inhalers such as dexamethasone sodium phosphate. Treatment protocols depend on the seriousness of exposure and the symptoms presented. Antibiotics may be administered if exposure results in bacterial bronchitis or pneumonitis. Phosgene reacts violently when in contact with strong oxidizers and attacks metals, plastic, and rubber. The molecular formula for phosgene is COClb2b.
A method to assess dermal absorption dynamics of chemical warfare agents: Finite doses of volatile compounds
Published in Journal of Occupational and Environmental Hygiene, 2022
From ancient times through two 20th-century world wars, chemical warfare agents (CWAs), including poison arrows, asphyxiants, and crude irritants (Worek et al. 2016), have been used in combat and during acts of violence and disobedience. Chemical warfare agents are organized into the following groups: nerve agents, vesicants (also known as blistering agents), blood agents, lung injurants, riot-control agents, psychotomimetic agents, toxins, and vomiting agents (Ganesan et al. 2010). Nerve agents interfere with the body's nervous system and enter through inhalation or dermal contact (Wexler and Anderson 2014). Vesicants cause severe chemical burns that may result in painful blisters (Hilmas and Hilmas 2009). This class of CWAs enters the body through inhalation, dermal, or ocular routes. Blood agents enter the bloodstream by either inhalation or ingestion, with nausea and dizziness being the early signs of exposure. Lung injurants, or choking agents, occur in the respiratory tract with symptoms including loss of breath and choking (Ganesan et al. 2010). The most commonly used classification of CWAs is riot-control agents, which temporarily disarm a person when either inhaled or contact is made to the eyes or skin (Wexler and Anderson 2005). Psychomimetic agents create hallucinations and are meant to incapacitate an individual by targeting the central nervous system (Ganesan et al. 2010). Toxins, commonly called biotoxins, are biological substances found in nature (Janik et al. 2019). Due to their intrinsic properties, these substances tend to appear in both chemical and biological warfare agents.