Chemical Properties
Arsine is a highly toxic, colorless gas with a garlic odor. It is soluble in water, benzene,
and chloroform. It is extremely flammable and explosive when exposed to heat, sparks, or
flames. Arsine decomposes on heating and under the infl uence of light and moisture, producing
toxic arsenic fumes. Arsine reacts with strong oxidants, causing explosion hazard
and may explosively decompose on shock, friction, or concussion. Workers in the metallurgical
industry involved in the production process and the maintenance of furnaces, and
in the microelectronics industry get exposed to the substance. Arsine is extensively used in
semiconductor industries, and in the manufacture of microchips.
Chemical Properties
colourless gas smelling of garlic
Air & Water Reactions
Highly flammable. On exposure to light, decomposes rapidly depositing shiny black arsenic.
Reactivity Profile
ARSINE decomposes into its elements (arsenic, gaseous hydrogen) when heated to 300°C. Can form accidentally by the reaction of arsenic impurities with mineral acids (hydrochloric acid, sulfuric acid) in the presence of common metals (iron, zinc). A reducing agent---not oxidized by air at room temperature [Kirk-Othmer, 3rd ed., Vol. 3, 1978, p. 251], but may react vigorously with other oxidizing agents [Sax, 9th ed., 1996, p. 279]. Moderately explosive in combination with chlorine or nitric acid. When heated to decomposition or ignited, ARSINE emits highly toxic fumes of metallic arsenic.
Health Hazard
ARSINE is highly toxic by inhalation; a very short exposure to small quantities may cause death or permanent injury. ARSINE is the most powerful hemolytic poison encountered in industry.
Fire Hazard
Vapors may travel to a source of ignition and flash back. Container may explode in heat of fire. When heated to decomposition, emits highly toxic fumes. Can react vigorously with oxidizing materials. May explode when exposed to chlorine, nitric acid, or potassium plus ammonia. On exposure to light, moist ARSINE decomposes quickly, depositing shiny black arsenic.
Hazard
Highly poisonous by inhalation. Periph-
eral nervous system and vacular system impairment,
kidney and liver impairment.
Health Hazard
Arsine is a highly toxic gas. It primarily targets the erythrocyte (red blood cell) and rapidly
induces intravascular hemolysis. Secondary effects resulting from hemolysis include
hemolytic anemia, hepatic and renal damage. The exact mechanism by which arsenic
causes erythrocytes to rupture is unknown, but it is believed to be due to either oxidative
damage or a reaction with sulfydryl. As stated, arsine is a potent hemolytic agent and
causes acute intravascular hemolysis, rapid red blood cell destruction, and renal failure.
Arsine is highly soluble in body fat and hence, can easily cross the alveolo-capillary
membrane and into the red blood cell. Arsine causes chemical burns. Exposures to
arsine cause headaches, malaise, weakness, dizziness, dyspnea; abdomen and back pain;nausea, vomiting, diarrhea, bronze skin; hematuria (hemoglobin in urine), jaundice,
liver enlargement, fever, anxiety, disorientation, delirium, shivering, muscular cramps,
tachypnea, tachycardia, anemia, hyperkalemia, electro-cardiographic changes, burning
sensations, peripheral neuropathy (focal anesthesia and paresthesia), agitation, disorientation,
and hallucinations. The exposed individual and/or the occupational worker
soon develops a sensation of cold and paresis in the limbs, hemoglobinuria, a garlic-like
odor to the breath, multi-organ failure, and massive hemolysis and kidney failure. Toxic
pulmonary edema or acute circulatory failure has been reported as the cause of death in
some cases of arsine poisoning. Studies have indicated that occupational exposures to
arsine cause increased rates of miscarriage among women associated with the semiconductor
industry.
Potential Exposure
Arsine is used in making electronic,
semiconductor components; in organic syntheses; and in
making lead-acid storage batteries. Arsine may be generated
by side reactions or unexpectedly; e.g., it may be generated
in metal pickling operations; metal drossing
operations; or when inorganic arsenic compounds contact
sources of nascent hydrogen. It has been known to occur as
an impurity in acetylene. Most occupational exposure
occurs in chemical, smelting, and refining industries. It has
been used as a poison gas. Cases of exposure have come
from workers dealing with zinc, tin, cadmium, galvanized
coated aluminum; and silicon and steel metals. A regulated,
marked area should be established where this chemical is handled, used, or stored in compliance with OSHA
Standard 1910.1045. SA is used as a military poison gas
(blood agent). It forms cyanide in the body.
First aid
If a person breathes in large amounts of this
chemical, move the exposed person to fresh air at once
and perform artificial respiration. If this chemical has
been inhaled, remove from exposure, begin rescue breathing
(using universal precautions, including resuscitation
mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility.
Dimercaprol treatment is indicated and blood transfusions
may be necessary. If this chemical gets into the eyes,
remove any contact lenses at once and irrigate immediately
for at least 15 minutes, occasionally lifting upper
and lower lids. Seek medical attention immediately. If
frostbite has occurred, seek medical attention immediately;
do NOT rub the affected areas or flush them with
water. In order to prevent further tissue damage, do NOT
attempt to remove frozen clothing from frostbitten areas.
If frostbite has NOT occurred, immediately and thoroughly
wash contaminated skin with soap and water.
Seek medical attention immediately. Medical observation
is recommended for 24 to 48 hours after breathing overexposure,
as pulmonary edema may be delayed. As first
aid for pulmonary edema, a doctor or authorized
paramedic may consider administering a drug or other
inhalation therapy.
Shipping
UN2188 Arsine, Hazard class: 2.3; Labels: 2.3-
Poisonous gas, 2.1-Flammable gas, Inhalation Hazard Zone
A. Cylinders must be transported in a secure upright position,
in a well-ventilated truck. Protect cylinder and labels
from physical damage. The owner of the compressed gas
cylinder is the only entity allowed by federal law (49CFR)
to transport and refill them. It is a violation of transportation
regulations to refill compressed gas cylinders without the
express written permission of the owner. Military driver shall
be given full and complete information regarding shipment
and conditions in case of emergency. AR 50-6 deals specifically
with the shipment of chemical agents. Shipments of
agent will be escorted in accordance with AR 740-32.
Incompatibilities
Arsine forms explosive mixture with air.
SA reacts with strong oxidizers, nitric acid, causing an
explosion hazard. Thermally unstable; shock, friction, and
concussion sensitive; can explosively decompose. Can
explode on contact with warm, dry air. Violent reaction
with acids, halogens, mixtures of potassium and ammonia.
Decomposes to metallic arsenic (fumes) on exposure to
light, moisture or upon decomposition from heat or
ignition.
Description
Arsine is a colorless, extremely toxic, flammable
gas at room temperature and atmospheric
pressure and is heavier than air. It has a mild
garliclike odor and acts as a blood and nerve
poison. It can be fatal if inhaled in sufficient
quantity and can form flammable mixtures with
air.
Arsine is shipped as a liquefied compressed
gas in steel cylinders under its own vapor pressure
of 219.7 psia (1515 kPa, abs). Arsine is
slightly soluble in both water and organic solvents.
It reacts readily with agents such as potassium
permanganate, bromine, and sodium
hypochlorite to form arsenic compounds. Arsine
is stable at room temperature, but begins to decompose
into its elements around 446°F to
464°F (230°C to 240°C).
Waste Disposal
Return refillable compressed
gas cylinders to supplier. Arsine may be disposed of by controlled
burning. When possible, cylinders should be sealed
and returned to suppliers. Seek guidance from regulatory
agencies as to proper disposal. Consult with environmental
regulatory agencies for guidance on acceptable disposal practices.
Generators of waste containing this contaminant
(≥100 kg/mo) must conform with EPA regulations governing
storage, transportation, treatment, and waste disposal.
Physical properties
Colorless gas; garlic-like unpleasant odor; liquefies at -55°C; solidifies at -116.3°C; heavier than air; gas density 2.695 (air =1); sparingly soluble in cold water (~ 20 mg/100 g water or about 640 mg/L at the NTP); soluble in chloroform and benzene.
Definition
A poisonous colorless gas
with an unpleasant smell. It decomposes to
arsenic and hydrogen at 230°C. It is produced
in the analysis for arsenic (Marsh’s
test).
Preparation
Arsine is produced by the reaction of arsenic trichloride, arsenic trioxide or
any inorganic arsenic compound with zinc and sulfuric acid. It is also made by
treating a solution of sodium arsenide or potassium arsenide in liquid ammonia
with ammonium bromide:
Na3As + 3NH4Br → AsH3 + 3NaBr + 3NH3
It may be also prepared by decomposition of alkali metal arsenides by water;
or arsenides of other metals with acids:
Ca3As2 + 6 HCl → 2 AsH3 + 3 CaCl2
A poor yield may be obtained if water is substituted for acids. Thus calcium arsenide reacts with water to produce about 15% arsine.
Flammability and Explosibility
Arsine is flammable in air, having a lower explosion limit (LEL) of 5.8%. The upper
limit has not been determined. Combustion products (arsenic trioxide and water) are
less toxic than arsine itself. In the event of an arsine fire, stop the flow of gas if
possible without risk of harmful exposure and let the fire burn itself out.
Materials Uses
Arsine is noncorrosive and may, therefore, be
used with most of the commercially available
metals. However, since arsine is mainly used for
the electronics industry, stainless steel is recommended
for the gas delivery systems. Stainless
steel regulators should be used for all highpurity
applications with arsine and arsine mixtures.
Physiological effects
Arsine is an extremely toxic gas that attacks the
nervous and circulatory systems and can be fatal
if inhaled in sufficient quantity. It is a powerful
hemolytic agent, and victims may have delayed
symptoms for up to 24 hours. Both chronic and
acute exposures to arsine are dangerous. Effects
of a single (acute) inhalation exposure include
rapid intravascular hemolysis, hemoglobinuria
with accompanying dark urine, malaise, dizziness,
headache, nausea, vomiting, abdominal
pain, diarrhea, and collapse. Pulmonary edema
may occur following overexposure. There may
be a delay of several hours before the onset of
signs or symptoms.
Effects of repeated (chronic) overexposure
may result in peripheral neuropathy, hyperpigmentation,
keratosis, cardiovascular disease,
and progressive anemia. Other effects of overexposure
include pulmonary edema, jaundice,
and severe hemolytic anemia. Severe kidney
damage may occur with oliguria or anuria leading
to uremia and death. Severe liver and cardiac
damage may also occur. There is evidence
(published in reports of the National Toxicology
Program and the International Agency for Research
on Cancer) that inorganic arsenic compounds
are skin and lung carcinogens in humans
Carcinogenicity
Arsenic has been considered a human carcinogen for a number of years(1),but the mechanisms underlying these processes have remained elusive due in part to the absence of an appropriate animal model. There
are a number of hypotheses for the mechanisms of arsenical action that include arsenical inhibition of DNA repair, cocarcinogenesis, and more recently the concept of arsenical production of ROS(65,66) that may act in concert with these mechanisms. It is clear from in vitro mutagenicity test systems that arsenicals are not direct-acting mutagens but rather act via some secondary mechanism(s). Given the long history and knowledge that arsenicals in air and water produce human cancers, this is a remarkable situation with regard to occupational and environmental exposures. Most studies of animals exposed to arsenate or arsenite by the oral route have not detected any clear evidence for an increased incidence of skin cancer or other cancers. Recently, a series of studies presented evidence that inorganic arsenic may be a transplacental carcinogen in animals. Waalkes et al. exposed timed pregnant mice to sodium arsenite in drinking water during gestation days 8–18. Dose-related increases in hepatocellular carcinomas and adrenal tumors in the male offspring and uterine hyperplasia in female offspring from treated dams were reported. The offspring also had increase in the number of malignant tumors. Aberrant estrogen signaling, potentially through inappropriate estrogen receptora, may play a role in the arsenic-induced tumors in these offspring.
Environmental Fate
Arsine acts predominantly as a hemolytic agent. Hemolysis
appears to be dependent on membrane disruption as a result
of arsine reactions with sulfhydryl groups and from formation
of hydrogen peroxide and adducts with oxyhemoglobin.
Failure of the kidneys and other organs is probably not only
due to the effects of red blood cell debris slugging within the
microcirculation but also to a direct toxic effect on the
organs.
storage
cylinders of arsine should be
stored and used in a continuously ventilated gas cabinet or fume hood. Local fire
codes should be reviewed for limitations on quantity and storage requirements.
Carbon steel, stainless steel, Monel?, and Hastelloy ?C are preferred materials for
handling arsine; brass and aluminum should be avoided. Kel-F? and Teflon? are
preferred gasket materials; Viton? and Nylon? are acceptable.
Toxicity evaluation
Arsine is relatively stable in air and may travel in the atmosphere
from a point of emission to remote areas, especially at
night before it is converted into nonvolatile oxidized
compounds, which may be further removed by particulate
matter or deposited back to the soil. Since arsine is decomposed
by the action of ultraviolet rays, its stability is reduced
during the day. Arsine is moderately soluble in water (20 ml per
100 ml at 20°C). After entering the water, arsine is likely to be
oxidized to other arsenic compounds, of which only a small
percentage remain in the water; the rest are deployed along the
zone of sediment, where they can undergo biomethylation by
microorganisms.
GRADES AVAILABLE
Arsine is usually sold in ultrahigh-purity grades
(99.9999 percent) primarily for use in the electronic
industry.
Manufacturers supply various grades of product
depending on the application and purity
requirements such as:
? Electronic Grade
? Ultra Large Scale Integration (ULSI)
Grade
? Metal Organic Chemical Vapor Deposition
(MOCVD) Grade
? Semiconductor Grade
? MegaBit Grade