Nerve agents volatile

The components, by-products of the reaction or solvents used to facilitate mixing the components may have their own toxic properties and could present additional hazards. They may also change the rate that the binary nerve agent volatilizes or penetrates the skin. Residual components may react with common materials, such as alcohols, to produce other nerve agents. For data on binary components, see the Component Section (C01-C) following information on the individual agents. 

G-series nerve agents Volatile decomposition products may include HF, HCl, HCN, sulfur oxides (SO ), phosphorous oxides (PO ), as well as potentially toxic oiganophosphates. In addition, toxic phosphate residue may remain. 

Are the same as the non-Binary Nerve Agents (see Class Indices COl through C04). Components, byproducts, or solvents may have toxic properties and present additional hazards. These materials may also impact the rate that the Binary Nerve Agents volatilize or penetrate the skin. 

They are generally divided into the G-agents, which in the unmodified state are volatile, and the V-agents, which tend to be more persistent. Even G-agents are capable of being thickened with various substances to increase the persistence and penetration of the intact skin. The principal nerve agents are Tabun (GA), Sarin (GB), Soman (GD), and VX. 

The agent GF is a fluoride-containing organophosphate. It is a potential nerve agent. It is a slightly volatile liquid that is almost insoluble in water. It enters the body primarily through the respiratory tract but is also highly... 

The mixture known as OPA is relatively nontoxic compared with nerve agents. However, it is not without hazard. It is a highly volatile and flammable liquid... 

DF and its precursor, DC are organophosphonic acids. They will react with alcohols to form crude lethal nerve agents, such as crude GB. High overexposure may cause inhibition of cholinesterase activity. Although much less toxic than GB, DF and DC are toxic and corrosive materials. Because DF and DC are relatively volatile compounds, the primary route of exposure is expected to be the respiratory system. However, ingestion also results from inhalation exposures in animals and could occur in humans. DF and DC vapors have a pungent odor and may cause severe and painful irritation of the eyes, nose, throat, and lungs. Data provided is for DF only, DC has similar properties. 

Characteristics Nerve agents are liquid under temperate conditions, but, when dispersed, the more volatile ones constitute both a vapor and a liquid hazard. However, the less volatile nerve agents represent primarily a liquid hazard (mainly, the G-agents are more volatile than the nerve agent VX, while sarin (GB) is the most volatile and nerve agent GF is the least volatile of the so-called G-agents. GB has an LCt-50 of 100 (vapor toxicity of mg-min/m3), an ICt-50 of 75 (vapor toxicity of mg-min/m30, and an MCt-50 of 3 (vapor toxicity of mg-min/m3). The LD-50 on skin is 1700mg. 

GF (cyclohexyl methyylphosphonofluorridate) is a low volatility nerve agent taken by inhalation either as a gas or aerosol. 

Because its ubiquity, perhaps it is only a matter of time before a terrorist group successfully uses cyanide in an attack. It should be borne in mind, however, that a substantial amount of HCN is required to cause death in most humans. For example, approximately 2,500-5,000 mg-minute/m is estimated to be the median lethal concentration (Baskin Brewer, 1997), compared to 100 mg-minute/m for sarin nerve agent (Sidell, 1997). One should also expect that successful attacks employing HCN, like other volatile agents, demand large quantities of agent and enclosed spaces. Even under such... 

GD is likely to undergo hydrolysis in most soils. As noted above, the rate of hydrolysis will be dependent upon temperature and pH. According to Morrill et al. (1985), evaporation is the primary mechanism for the loss of the GA and GB nerve agents from soil. Although the G agents are liquids under ordinary environmental conditions, their relatively high volatility and vapor pressure permits them to be disseminated in vapor form. Because of this volatility, GD is not expected to persist in soils. 

The USA adopted sarin as its nerve agent after the war and then developed a more sophisticated gas, VX. This is not volatile and is described as persistent, remaining in a sprayed area, whereas sarin is non-persistent, that is, it evaporates and therefore a sprayed area becomes less hazardous with time. 

The G-agents are all viscous liquids of varying volatility (vapor density relative to air between 4.86 and 6.33) with faint odors ( faintly fruity , or spicy , odor of camphor ). Agent VX is an amber-colored hquid with a vapor density of 9.2, and is considered odorless. Thus, nerve agent vapors possess little to no olfactory warning properties (Table 6.1). 

Nerve agent Vx exhibits volatility (76.4 mg/m at 25°C) intermediate to that of agents GA and VX, and a vapor density (7.3) intermediate to that of agents GF and VX Vx is also considered persistent . There are few data from which to characterize nerve agents VE (O-Ethyl-5-[2-(diethylammo) ethyljethylphosphonothioate, CAS No. 21738-25-0) or VM (0-Ethyl-5 -[2-(diethylamino)ethyl]-methylphosphonothioate, CAS No 21770-86-5). 

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