Phosgene respiratory toxicity

Highly toxic perfluoroisobutylene (PFIB) poses a serious health hazard to the human respiratory tract. PFIB is a thermal decomposition of polytetrafluo-roethylene (PTFE), e.g., Teflon. PFIB is approximately lOx as toxic as phosgene. Inhalation of this gas can cause pulmonary edema, which can lead to death. PFIB is included in Schedule 2 of the Chemical Weapons Convention (CWC), the aim of the inclusion of chemicals such as PFIB was to cover those chemicals, which would pose a high risk to the CWC. 

Suggested Alternatives for Differential Diagnosis Acute respiratory distress syndrome, congestive heart failure, pulmonary edema, AIDS, pneumonia, cardiogenic shock, septic shock, phosgene toxicity, phosphine toxicity, salicylate toxicity with pulmonary edema, influenza, plague, tularemia, and anthrax. 

The upper and lower respiratory tracts respond differently to the presence of toxicants. The upper respiratory tract is affected mostly by toxicants that are water soluble. These materials either react or dissolve in the mucus to form acids and bases. Toxicants in the lower respiratory tract affect the alveoli by physically blocking the transfer of gases (as with insoluble dusts) or reacting with the wall of the alveoli to produce corrosive or toxic substances. Phosgene gas, for example, reacts with the water on the alveoli wall to produce HC1 and carbon monoxide. 

CNS depression, cardiac arrythmias, respiratory depression, and death. Halo-genated hydrocarbons decompose when heated and become a toxic gas (e.g., hydrogen chloride, phosgene). Evaporation of halogenated hydrocarbons as propellants causes intense cold, which leads to numbness. These gases have been used as topical analgesics. 

DOT CLASSIFICATION 6.1 Label Poison, Flammable Liquid, Corrosive SAFETY PROFILE Poison by ingestion, inhalation, and intraperitoneal routes. Moderately toxic by skin contact. Human systemic effects by inhalation conjunctiva irritation and respiratory effects. Corrosive to skin, eyes, and mucous membranes. Very dangerous fire hazard when exposed to heat sources, sparks, flame, or oxidizers. Reacts with water or steam to produce toxic and corrosive fumes. When heated to decomposition it emits toxic fumes of CL, methyl chloroformate, and phosgene. 

Green Cross Gases. This includes substances with a high vapour tension and great toxic power on the respiratory tract phosgene, trichloromethyl chloroformate (diphosgene), chloro-picrin, etc. 

A) The Toxic Suffocants (or Lung Irritants). These include those gases which act principally on the respiratory tract chlorine, phosgene, chloropicrin, etc. 

Little is known about lewisite s stability in the environment, but it can react with water in a manner whereby its volatility and most of its blistering potency are lost. As a potent blister agent, it has irritant effects on the eyes and respiratory system, and has similar toxicities to the other blister agents mentioned above (except that it exhibits less bone marrow suppression). Similar to its dichloroarsine cousins and phosgene oxime, but unlike the mustard vesicants, it can cause pain at the time of initial contact. There is often no erythema around the vesicles as with other mustard agents. 

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