Agent GD Soman

L Acute Toxicity. Lethality data for agent GD are summarized in Table 28. The estimated oral LD50 value for humans is 5-20 Lig/kg (Somani et al. 1992). Gause et al. (1985) reported that the threshold for seizure induction in juvenile male baboons was 5 pg GD/kg when administered by i.m. injection. Bucci et al. (1992c) conducted range-finding studies with rats. The test material was administered by gavage to male and female CD rats once per day, 5 d/wk, for 2 wk. These studies indicated that the maximum dose tolerated by CD rats was 

70 [ig kg d , and a dose of 300 Lig kg d was lethal to 100% of the test animals. Sterri et al. (1980, 1981) reported that repeated injections of soman in rats, guinea pigs, and mice led to cumulative LD50 doses markedly higher than the acute ones. The observed tolerance toward soman was thought to result from recovery of plasma aliesterase and plasma ChE (Sterri et al. 1981). 

Chronic Toxicity. Information on the toxicity of agent GD to humans or animals following chronic exposures was not found in the available literature. 

Developmental and Reproductive Effects, No studies evaluating the developmental or reproductive effects of GD in humans or laboratory animals were located in the available literature. 

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HEALTH RISK ASSESSMENT FOR NERVE AGENT GD (SOMAN)... 

Methylphosphonofluoridate-Pinacolyl Common Name(s) Nerve Agent GD, Soman, TrUon Dosage . oooiozfsmg)... 

Does not include suspect incidence of Chemical Agent Identification Sets (CAIS). These sets were training aids containing vials of various chemical warfare agents. See USACMDA (1993 a,b) for more detailed explanation. Agent GD (soman), pinacolyl methyl phosphonofluoridate, is a lethal anticholinesterase and is known from only one stockpile site. 

Agent GD (soman, pinacolyl methylphosphonofluoridate CAS no. 96-64-0) is a colorless liquid with a molecular weight of 182.2 (DA 1974 MacNaughton and Brewer 1994). Its chemical structure is... 

Agent GD (Soman). RfDg = 4 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 the default value of 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. A LOAEL-to-NOAEL uncertainty factor of 3 was used because... 

Chemical Agent GD The chemical Pinacolyl methyl phosphonofluoridate (CAS 96-64-0) also known as soman, is a nerve agent. 

GD (Soman — Phosphonoflouridic acid. Methyl, 1,2,2-Trimethyl-propyl ester [R-(R, R )]) A nerve agent discovered in 1944. 

Bucci, T.J., R.M. Parker, J.A. Crowell, J.D. Thurman, and P.A. Gosnell. 1992. Toxicity Studies on Agents GB and GD (Phase II) 90 Day Subchronic Study of GD (Soman) in CD Rats. Final Report. FDA 224-85-0007. DTIC ADA257182. Prepared by the Nation Center for Toxicological Research, Jefferson, Ark., for the U.S. Army Biomedical Research and Development Laboratory, Fort Detrick, Frederick, Md. 

The G-nerve agents include GA (tabun, ethyl A,A-dimethyl-phosphoramidocyanidate), GB (sarin, isopropyl-methylphosphonofluoridate), GD (soman, 1,2,2-tri-methylpropyl methylphosphonofluoridate), and VX (o-ethyl 5-[2-(diisopropylamino)ethyl] methylphosphonothiolate). The V-type nerve agents are several orders of magnitude less volatile than the G-type agents and act primarily as a liquid via the percutaneous route for example, VX is several orders of magnitude more lethal percutaneously than sarin (Reutter, 1999). 

Schedule 1 includes the following toxic chemicals - the chemical classes for nerve agents which include GB (sarin), GD (soman), G A (tabun) and VX, a number of sulfur mustards, three lewisites, three nitrogen mustards, saxitoxin, ricin and a number of precursors. 

Introduction. Nerve agents are primarily organophosphorus esters similar to insecticides. Although some have been given names, they are usually known by their code letters GA (TABUN), GB (SARIN), GD (SOMAN), and VX. 

Bucci, T. J., Parker. R. M.. and Gosnell, P. A. (1992b). Toxicity studies on agents GB and GD (phase IJ) 90-day subchronic study of GD (soman) in CD rat.s, Final report (FDA 224-85-0007). Prepared by the National Center for Toxicological Research, Jefferson, AR, for the U.S. Department of the Army, Biomedical Research and Development Laboraioty, R. Dctrick, MD,... 

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