What arsine is

• Arsine is a colorless, nonirritating toxic gas with a mild garlic odor. The odor can be detected only at levels greater than those necessary to cause poisoning.
• Arsine is formed when arsenic comes in contact with an acid.
• Arsine is similar to a gas called stibine, which is formed when the metal antimony comes in contact with an acid. Stibine has health effects similar to those of arsine, but it is not as widely available, and it has a much more noticeable odor (like rotten eggs).

Where arsine is found and how it is used

• Although arsine was investigated as a warfare agent during WWII, it was never used on the battlefield.
• Arsine is most commonly used in the semiconductor and metals refining industries.

How you could be exposed to arsine

• Most common reports of exposure to arsine have been after accidental formation of arsine in the workplace.
• Inhalation (breathing in the gas) is the most likely route of exposure after arsine is released into the air.
• Absorption into the body through the eyes and the skin has not been known to occur.
• Arsine vapor is heavier than air, so it would be more likely to settle in low-lying areas.

How arsine works

• The extent of poisoning caused by arsine depends on the amount of arsine to which a person has been exposed and on the length of time of the exposure.
• Depending on the intensity of exposure to arsine, symptoms may occur 2 to 24 hours after exposure. However, exposure to high doses of arsine can be immediately fatal.
• After arsine enters the bloodstream, it damages the red blood cells and leads to symptoms as a direct result of this damage.

Signs and symptoms of arsine exposure

At lower doses, people may not know they have been exposed to arsine, because it has no odor. At higher doses, a mild garlic odor has been reported. Stibine, on the other hand, has a strong odor, so people will probably be aware that they may have been exposed to something. People exposed to a low or moderate dose of arsine by inhalation may experience some or all of the following symptoms within 2 to 24 hours of exposure:

• Weakness
• Fatigue
• Headache
• Drowsiness
• Confusion
• Shortness of breath
• Rapid breathing
• Nausea, vomiting, and/or abdominal pain
• Red or dark urine
• Yellow skin and eyes (jaundice)
• Muscle cramps

Exposure to a large dose of arsine by any route may result in these additional health effects:

• Loss of consciousness
• Convulsions
• Paralysis
• Respiratory failure, possibly leading to death
• Showing these signs and symptoms does not necessarily mean that a person has been exposed to arsine.

Long-term health effects of arsine exposure

Severely exposed people are not likely to survive. If people survive the initial exposure, long-term effects may include kidney damage, numbness and pain in the extremities, and neuropsychological symptoms such as memory loss, confusion, and irritability.

How you can protect yourself, and what to do if you are exposed to arsine

• Because no antidote exists for arsine exposure, the best thing to do is avoid it. First, get fresh air by leaving the area where the arsine was released. Moving to an area with fresh air is a good way to reduce the possibility of death from exposure to arsine.
  • If the arsine release was outside, move away from the area where the arsine was released.
  • If the arsine release was indoors, get out of the building.