Four compounds from shuttle can harm on contact
ATLANTA, Georgia (CNN) -- Four compounds used on the space shuttle Columbia could pose an immediate hazard to people on the ground, a NASA spokeswoman said Sunday.
The deadliest chemical of the four would not provide any warning to someone who touched it, according to toxicology databases.
Officials have also warned that some of the debris may contain explosive materials.
They said that areas such as the shuttle's cabin door and parachute deployment areas were rigged to be operated by explosive systems and munitions experts have been deployed to deal with any debris suspected of presenting that risk.
The hazardous compounds are: two forms of hydrazine, nitrogen tetroxide and a pure form of ammonia.
Raw hydrazine fueled the shuttle's auxiliary power units, which generated hydraulic pressure for various functions in the shuttle.
Another form of the chemical, monomethyl hydrazine, fueled the shuttle's maneuvering systems while it was in space, said Randy Azera, a former NASA engineer and consultant to CNN.
Both forms of hydrazine are clear, flammable liquids. They can irritate the eyes, skin and respiratory system and cause vomiting, diarrhea, tremors, convulsions and permanent damage to internal organs. They are considered "immediately dangerous to life" at a concentration of 50 parts per million.
They are not considered to have warning signs of contact but can be detected in the blood of an exposed person.
Anyone who suspects contact with the chemicals is urged to seek medical help. Flushing with water for at least 15 minutes is recommended after suspected contact.
Nitrogen tetroxide and monomethyl hydrazine are "hypergolic" propellants, meaning they ignite spontaneously when they come in contact with each other, a useful property for maneuvering systems.
Nitrogen tetroxide is a reddish-brown gas at room temperature and has a "pungent, sweetish" smell, according to experts.
It can injure the eyes and skin on contact, and, if inhaled, can damage the lungs.
A single exposure can prove fatal, but only high concentrations produce immediate symptoms.
Warning signs of contact might not appear for hours after exposure, and extreme symptoms might not show up for days, so a victim might be unaware he or she has been exposed until it is too late for treatment.
People who suspect contact with the chemical are urged to flush their body and clothes with large amounts of water, and, if necessary, remove their clothing and bathe with soap and water at least 15 minutes. Eyes should be held open and flushed with water for at least as long. People who suspect contact should be taken to a hospital or doctor as soon as possible.
Pure ammonia is a clear liquid at normal temperatures with a pungent smell. It was used as a coolant to remove heat from the electrical systems on the orbiter engines. It can blister a person's lungs if it is inhaled and can cause death in high concentrations.