Properties of Toxic Chemical Agents

Toxicity A relative property of a chemical agent and refers to a harmful effect on some biologic mechanism and the condition under which this effect occurs. 

One potentially attractive approach to the destruction of the chemical warfare agents is chemical hydrolysis reaction with water to form products of reduced toxicity. In a chemical demiUtarization context, the process is known as neutralization, because it neutralizes the toxic properties of the chemical agent. 

Toxicity . (1) The measure of the adverse effect exerted on the human body by a poisonous material. (2) A relative property of a chemical agent with reference to a harmfirl effect on some biological mechanism and the condition under which this effect occurs. The quality of being poisonous. Ashford NA, Miller CS (1997) Chemical exposures low levels and high stakes. John Wiley and Sons, New York. 

In addition, another important property of some chemical agents is not only their capacity to cause skin lesions but also to be absorbed through the skin into the circulation and have general toxic effects on the patient including liver, kidney, and other vital organs of the body. Such chemical agents include phenols, cresols, chromic and formic acids, and other organic chemical substances. Extensive lesions from acids and alkalis may also lead to acidosis or alkalosis that will have to be treated. 

The interplay between the chemical and biological properties of the threat agent, on the one hand, and the specific attack scenario, on the other, can influence the lethality of the attack. Table 2-2 shows the relative respiratory toxicities (expressed as the lethal concentration of toxin at which 50 percent of test animals are killed, or LCT50, in milligrams per minute per cubic meter) of a variety of toxic gases compared with chlorine gas, which was used as a chemical weapon in World War I. According to Table 2-2, the nerve agent sarin (GB) has a respiratory toxicity approximately 100 times that of chlorine, while sulfur mustard (HD) is about 7 times more toxic. However, the lethality of an attack... 

Be familiar with the properties of all chemicals used in the laboratory. This includes their flammability, reactivity, toxicity, and proper disposal. This information may be obtained from your instructor or from an MSDS. Always wear disposable gloves when using potentially dangerous chemicals or infectious agents. 

The toxic, explosive, and flammable properties of some chemicals make them potential weapons in the hands of terrorists (Institute of Medicine, 2002). Many such chemicals (see Table 25.1) are commonly produced, transported, and used in large quantities in the United States. The potential for exposure is significant, and exposure to these agents can cause serious injury and... 

Toxins, new-generation nerve agents, and toxic industrial chemicals have chemical properties different from those of traditional chemical agents. Fielded decontamination materials may not be effective against some of these threats. 

The effects of chemical agents on food depend on the properties of both the agent and the food. Contamination of water may lead to a toxic hazard when it is used for food preparation. 

Unfortunately, these data are scarce in literature and refer to the original combat warfare agents only. Data on toxic WA transformation products, formed both as a result of WA intake in the environment and technological processes associated with WA destruction and utilisation, are practically non-existent. However, proceeding from the physico-chemical properties of some warfare agents (e.g. yperite and lewisite), transformation products comparable with the original compounds in toxicity and sometimes exceeding them by 2-5 times are expected to be formed. In these cases, their stability in the environment is unknown. 

Many of the chemical agents cannot be tested in full-scale outside exercises. Information about them must be inferred from "simulants —that is, compounds that closely approximate the properties of the molecule in as many properties as possible other than toxicity—or by... 

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