Agent GB Sarin

Agent GB (sarin) is an organophosphate ChE inhibitor similar in mode of action and toxic effects to agents GA, GD, and VX. Agent GB is volatile and also soluble in water. It is acutely toxic by all routes of exposure, inhalation, inges- 

Grob and Harvey (1958) administered multiple oral doses of GB to human volunteers during a 3-d period (3-24 hr apart average, 7.5 hr). In two individuals, doses of 0.0005 or 0.005 mg/kg, totaling 0.007 mg/kg over the 3-d period, reduced RBC-ChE 33% and 27%, respectively, but neither produced toxic effects. Multiple doses of 0.008-0.016 mg/kg, totaling 0.088 mg/kg over the 3-d 

lower than control and preexposure values, based on ANOVA and Dunnett s comparison (ORNL). Source Bucci and Parker (1992). 

Colony rats Fischer-344 rats Colony mice A strain mice Beagle dogs 

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Dr. Aghajanian also tried the nerve agent GB (sarin) as a possible antidote. It worked quite well, as did VX, another well-known lethal nerve agent. He and Dr. Sidell sueeessfully used both drugs to reverse EA 3580 intoxieation. If not for the general publie fear of anything to do with nerve gas, one might reeommend sarin or VX as superior antidotes to use in the treatment of dmg-indueed delirium. 

Common Name(s) Nerve Agent GB, Sarin, Zarin Dosage . ooooioz(.5mg)... 

November 25, 2000— The nerve agent GB (sarin) is detected in employees work clothes. The workers come in from inspecting filters outside in cold weather and apparently the sarin begins vaporizing as their clothing warmed up. 

FIGURE 2-5 Hydrolysis of the nerve agent GB (sarin). SOURCE Flamm (1987). 

Agent GB (sarin isopropyl methylphosphonofluoridate, CAS no. 107-44-8) is a clear to straw-colored or amber liquid with a molecular weight of 140.1 (DA 1974 MacNaughton and Brewer 1994). Its chemical structure is... 

Agent GB (Sarin). RfDe = 2 x 10 mg kg d". A LOAEL was identified in a 90-d oral study in rats. A total uncertainty factor of 3000 was applied to account for protection of sensitive subpopulations (10), animal-to-human extrapolation (10), LOAEL-to-NOAEL extrapolation (3), extrapolation from a subchronic to chronic exposure (3), and incomplete data base (3). An uncertainty factor of 3 rather than 10 was used to extrapolate from a subchronic to chronic exposure because of the unlikelihood that the LOAEL would have been substantially lower if the exposure had continued for a longer period of time. The LOAEL-to-NOAEL uncertainty factor of 3 was used because the endpoint, cholinesterase inhibition, was not associated with any physical signs of clinical toxicity. A pilot multigeneration reproductive toxicity study on GB was inconclusive however, because the available evidence indicates that organophosphate cholinesterase inhibitors such as GB are not likely to be reproductive toxins, the lack of definitive results was not considered critical. Therefore, a UFd of 3, not the default value of 10, was applied. 

VX (6,7) is estimated to be about three times as potent a respiratory agent as sarin (GB) but about a hundred times as potent as a percutaneous... 

Production, Import/Export, Use, Release, and Disposal. The risk for exposure of the general population to substantial levels of diisopropyl methylphosphonate is quite low. GB (Sarin) and diisopropyl methylphosphonate have not been produced in the United States since 1957, and there is no indication that U.S. production of these chemicals will resume (EPA 1989). No information exists regarding the import or export of diisopropyl methylphosphonate. Diisopropyl methylphosphonate has no known commercial uses, but has been used by the military as a simulant for chemical warfare agents (Van Voris et al. 1987). 

Final Recommendations for Protecting Human Health From Potential Adverse Effects of Exposure to Agents GA (Tabun), GB (Sarin), and VX." Federal Register 68, No. 196 (October 9, 2003) 58348-58351. 

There are seven sites in the United States where U.S. Unitary Chemical Stockpile exists. Below they are listed by chemical weapon as follows GB, sarin H, mustard HD, mustard HT, mustard VX, persistent nerve agent GA, tabun L, lewisite TGA, thickened tabun TGB, thickened sarin. 

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. 

C.A.S. Registration Number Chemical Abstracts Service. An assigned number used to identify a material. CAS numbers identify specific chemicals and are assigned sequentially the number is a concise, unique means of material identification. A product of more than one component will have a specific number for each component (i.e., the CAS for lethal nerve agent GA, or tabun, is 77-81-9 while the CAS for the liquid nerve agent GB, or sarin, is 107-44-8, and 50.642-23-4). 

Chemical Agent GB The chemical Isopropyl methyl phosphonofluoridate (CAS 107-44-8) also known as sarin, is a nerve agent. 

GB Sarin, a nerve agent, more toxic than tabun or soman. 

GB sarin (a nerve agent) SWMU solid waste management unit... 

Bucci, T.J., and R.M. Parker. 1992. Toxicity Studies on Agents GB and GD (Phase II) 90 Day Subchronic Study of GB (Sarin, Type II) in CD Rats. Final Report. FDA 224-85-0007. DTIC AD-A248618. Prepared by the National Center for Toxicological Research, Jefferson, Ark., for the U.S. Army Biomedical Research and Development Laboratory, Fort Detrick, Frederick, Md. 

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