VX
Flammability | 1 | |
Toxicity | 4 | |
Body Contact | 2 | |
Reactivity | 1 | |
Chronic | 2 | |
SCALE: Min/Nil=0 Low=1 Moderate=2 High=3 Extreme=4 |
Chemical warfare agent (nerve gas).
C11-H26-N-O2-P-S, C11-H26-N-O2-P-S, "phosphonothioic acid, methyl-, S-[2-(bis(1-
methylethyl)amino)ethyl]O-ethyl ester", "phosphonothioic acid, methyl-, S-[2-(bis(1-
methylethyl)amino)ethyl]O-ethyl ester", "O-ethyl S-[2-(bis(1-methylethyl)amino]ethyl
methylphosphonothioate", "O-ethyl S-[2-(bis(1-methylethyl)amino]ethyl
methylphosphonothioate", "methylphosphonic acid, S-[2-bis(1-methylethyl)amino)ethyl] O-
ethyl ester", "methylphosphonic acid, S-[2-bis(1-methylethyl)amino)ethyl] O-ethyl ester",
"O-ethyl S-[2-(diisopropylamino)ethyl]methylphosphonothioate", "O-ethyl S-[2-
(diisopropylamino)ethyl]methylphosphonothioate", TX-60, MPT, "chemical warfare agent",
"organophosphorus nerve gas"
Although ingestion is not thought to produce harmful effects, the material may still be damaging to the health of the individual following ingestion, especially where pre- existing organ (e.g. liver, kidney) damage is evident. Present definitions of harmful or toxic substances are generally based on doses producing mortality (death) rather than those producing morbidity (disease, ill-health). Gastrointestinal tract discomfort may produce nausea and vomiting. In an occupational setting however, ingestion of insignificant quantities is not thought to be cause for concern. Considered an unlikely route of entry in commercial/industrial environments. Symptoms may be nausea, headache, giddiness, blurred vision, contractionof pupils, vomiting. Ingestion may produce nausea, vomiting, depressed appetite, abdominal cramps,and diarrhea.
Although the material is not thought to be an irritant, direct contact with the eye may produce transient discomfort characterized by tearing or conjunctival redness (as with windburn). Direct eye contact can produce tears, eyelid twitches, pupil contraction, loss of focus, and blurred or dimmed vision. Dilation of the pupils occasionally occurs.
The material is not thought to produce adverse health effects or skin irritation following contact (as classified using animal models). Nevertheless, good hygiene practice requires that exposure be kept to a minimum and that suitable gloves be used in an occupational setting. Toxic effects may result from skin absorption. Absorption by skin may readily exceed vapor inhalation exposure. Symptoms for skin absorption are the same as for inhalation. BE AWARE: Repeated minor exposures with only mild symptoms may have serious cumulative poisoning effect. Bare unprotected skin should not be exposed to this material. There may be sweating and muscle twitches at site of contact. Reaction may bedelayed by hours.
Inhalation may produce severe health damage*. The material is not thought to produce respiratory irritation (as classified using animal models). Nevertheless inhalation of the material, especially for prolonged periods, may produce respiratory discomfort and occasionally, distress. Inhalation hazard is increased at higher temperatures. Poisoning due to cholinesterase inhibitors causes symptoms such as increased blood flow to the nose, watery discharge, chest discomfort, shortness of breath and wheezing. Other symptoms include increased production of tears, nausea and vomiting, diarrhea, stomach pain, involuntary passing of urine and stools, chest pain, breathing difficulty, low blood pressure, irregular heartbeat, loss of reflexes, twitching, visual disturbances, altered pupil size, convulsions, lung congestion, coma and heart failure. Nervous system effects include inco-ordination, slurred speech, tremors of the tongue and eyelids, and paralysis of the limbs and muscles of breathing, which can cause death, although death is also seen due to cardiac arrest.
Principal routes of exposure are usually by skin contact with the material, skin contact with the mixed material and inhalation of vapor/spray mist. Repeated or prolonged exposures to cholinesterase inhibitors produce symptoms similar to acute effects. In addition workers exposed repeatedly to these substances may exhibit impaired memory and loss of concentration, severe depression and acute psychosis, irritability, confusion, apathy, emotional liability, speech difficulties, headache, spatial disorientation, delayed reaction times, sleepwalking, drowsiness or insomnia. An influenza-like condition with nausea, weakness, anorexia and malaise has been described. There is a growing body of evidence from epidemiological studies and from experimental laboratory studies that short-term exposure to some cholinesterase-inhibiting insecticides may produce behavioral or neuro- chemical changes lasting for days or months, presumably outlasting the cholinesterase inhibition. Although the number of adverse effects following humans poisonings subside, there are still effects in some workers months after cholinesterase activity returns to normal. These long-lasting effects include blurred vision, headache, weakness, and anorexia. The neurochemistry of animals exposed to chlorpyrifos or fenthion is reported to be altered permanently after a single exposure. These effects may be more severe in developing animals where both acetyl- and butyrylcholinesterase may play an integral part in the development of the nervous system. Padilla S., The Neurotoxicity of Cholinesterase-Inhibiting Insecticides: Past and Present Evidence Demonstrating Persistent Effects. Inhalation Toxicology 7:903-907, 1995.