Sarin chemistry

Sanchez F, Rodriguez-Alavarez MJ (1999) Effect of pH, conductivity and sediment size on thorium and radium activities along Jucar River (Spain). J Radioanal Nucl Chem 242 671-681 Sarin MM, Krishnaswami S, Somayajulu BLK, Moore WS (1990) Chemistry of U, Th, and Ra isotopes in the Ganga-Brahmaputra river system Weathering processes and fluxes to the bay of Bengal. Geochim Cosmochim Acta 54 1387-1396... 

Dalai TK, Krishnaswami S, Sarin MM (2002) Major ion chemistry in the headwaters of the Yamuna river system chemical weathering, its temperature dependence and C02 consumption in the Himalaya. Geochim Cosmochim Acta 66(19) 3397-3416... 

TABLE 1. Second-order rate constants for nucleophilic substitution of sarin, soman and DEP by oximates in aqueous solution at 25.0 °C. Erom Terrier etal., Org. Biomol. Chem., 4, 4352 (2006). Reproduced by permission of The Royal Society of Chemistry... 

The quantity of sarin made in October 1993 was 20gms 1 kg in November 1993 5 kg in December 1993 20 kg between February and March 1994. Anthony Tu, Chemistry and Toxicology of Nerve Gas Incidents in Japan in 1994 and 1995, paper presented at the Third Congress of Toxicology in Developing countries (1 September 1996), Cairo. 

Sarin, M.M., Krishnaswami, S., Dilli, K., Somayjulu, B.L., and Moore, W.S. (1989) Major ion chemistry in the Ganges-Bramaputra River system weathering processes and fluxes to the Bay of Bengal. Geochim. Cosmochim. Acta 53, 997-1009. 

According to inpatient records from St Luke s Hospital, the most common laboratory finding related to sarin toxicity was a decrease in plasma cholinesterase (ChE) levels in 74% of patients. In patients with more severe toxicity, plasma ChE levels tended to be lower, but a more accurate indication of ChE inhibition is measurement of erythrocyte ChE, as erythrocyte ChE (AChE) is considered true ChE and plasma ChE is pseudo ChE . However, erythrocyte ChE is not routinely measured, whereas plasma ChE is included in many clinical chemistry panels thus, it can be used as a simple index for ChE activity. In both the Matsumoto and Tokyo subway sarin attacks, plasma ChE served as a useful index of sarin exposure. In 92% of hospitalized patients, plasma ChE levels returned to normal on the following day. In addition, inpatient records from... 

Pande K., Sarin M. M., Trivedi J. R., Krishnaswami S., and Sharma K. K. (1994) The Indus River system (India-Pakistan) major-ion chemistry, uranium and strontium isotopes. Chem. Geol. 116, 245 -259. 

Chemistry Like tabun, sarin was first prepared (1938) by Schrader s group at LG. Farben. An early synthesis involved the use of methylphosphonic dichloride (CH3P(0)Cl2) as a starting material. An interesting route involves the reaction of a tetraalkoxysilane, (RO)4Si, as a source of the alkoxy fragment in GB (Black and Harrison, 1996a). 

Chemistry The synthesis of soman is similar to that of sarin. The major alteration is that pinacolyl alcohol replaces isopropanol. Soman hydrolyzes over a range of pHs, with pinacolyl methylpho-sphonate and fluoride ions being the initial products. Subsequent hydrolysis of pinacolyl methyl-phosphonate is similar to the aging process associated with GD poisoning (below) (Michel et al., 1967). 

Reesor, J.B., Perry, B.J., and Sherlock, E. 1960. The synthesis of highly radioactive methylphosphonofluor-idate (Sarin) containing P as a tracer element. Canadian Journal of Chemistry, 38 1416-1427. 

Takahashi Masayo was one of four members accused in the 1995 Tokyo sarin gas attack, and he outlined a sequence of events in court. In this sequence, Takahashi indicated that in March 1993, Asahara gave orders to manufacture sarin gas, however it has not been ruled impossible that such plans were made as early as 1990 (Reader 72). An Aum official named Murai Hideo (who was murdered in April 1995) is believed to have received Asahara s orders to develop chemical weapons (Reader 73). Murai then placed Tsuchiya Masami, who has a Master s degree in organic chemistry, in charge of chemical weapons research (Reader 73). 

Nozaki H, Hori S, Shinozawa Y, et al Secondary exposure of medical staff to sarin vapor in the emergency room. Intensive Care Med 21 1032-1035, 1995 O Brien RD Toxic Phosphorus Esters Chemistry, Metabolism, and Biological Effects. New York, Academic Press, 1960... 

The chemistry illustrated in equation 17 was developed to meet the requirements of the binary weapons system. In the absence of base, the reaction of an alcohol with methylphosphonic difluoride (11) is slow and requires heating to drive to completion. In the presence of an amine, the reaction is extremely rapid and exothermic and proceeds in good yield. For the (US) binary munitions system for sarin, a mixture of propan-2-ol and isopropylamine are brought together with methylphosphonic difluoride when the separate canisters containing the reactants are ruptured as a result of the shock caused by firing the munition. The chemical reaction occurs within the time of flight of the munition ". ... 

The chemistry of DFP, sarin and soman is essentially that of the P—F bond with initial bond breaking occurring invariably at that position by nucleophilic substitution of fluorine. This generally occurs under mild conditions with a wide variety of nucleophiles. The reaction with a nucleophilic serine hydroxyl group in AChE, with the displacement of... 

The volumes filtered are quite different, ranging from milliliters for microscopic studies to cubic meters for extensive chemical studies (Handa et al., 1970). Recovering sufficient material without undergoing any degradation is one of the main difficulties for precise organic chemistry studies. The utilization of immersed pumps allows the filtration of large volumes of sea water, even when the ship is underway (Krishnaswami and Sarin, 1976). 

Between November 1999 and November 2000, the EDS Phase 1 (EDS -1) was tested at a military installation at Porton Down in the United Kingdom. In early 2001, it was used in an emergency action to dispose of six bomblets containing the nerve agent sarin at Rocky Mountain Arsenal (RMA) in Colorado. Subsequently, four more bomblets were discovered during remediation of the same area at RMA. At this writing, the EDS-1 had been dispatched to dispose of these also. As a result of the success of these operations, the decision was made to discontinue development of the MMD, another mobile system that used the same process chemistry as the EDS to destroy chemical agent but that was both more complex and less versatile than the EDS. 

G, J., John, H., Melzer, M., et al., 2010. Stable adducts of nerve agents sarin, soman and cyclosarin with TRIS, TES and related buffers compounds—characterization by LC-ESI-MS/MS and NMR and implications for analytical chemistry. J. Chromatogr. B 878, 1382-1390. 

Sarin, A., Biodiesel Production and Properties, 2012, Royal Society of Chemistry, Cambridge, U.K., 16. 

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