From corrosive fuels to ammonia-like liquids, insulation and plastics, space shuttle Columbia carried a witch's brew of toxic and caustic materials designed to work in the hostile environment of space. Authorities warned the public to stay away from shuttle debris because it could be harmful.
"There's nothing on the shuttle beneficial to humans. The fuel, the propellant, all can be very abrasive," said Gene Perry, an engineer who worked on early space station plans put together at the Marshall Space Flight Center in Huntsville, Ala.
Perry said either liquid oxygen from the shuttle's fuel system or liquid nitrogen used to inflate the tires could be dangerous.
The trouble is twofold: Liquid nitrogen could combine with oxygen in the atmosphere to form nitrous oxide, a gas that can be fatal if inhaled. The second possibility is that either liquid oxygen or liquid nitrogen can severely burn anything or anyone it touches, Perry said.
Texas Department of Health spokesman Doug McBride said they were awaiting word from the Centers for Disease Control and Prevention and NASA as to what hazards the debris may contain.
"We don't know what kind of chemicals are on the spacecraft," he said.
Much of the debris scattered across Nacogdoches, where authorities ordered people to stay 100 yards away from the debris because of contamination fears. Those who had touched the wreckage were urged to get medical attention.
"What we fly in space is operated in many cases with toxic propellant and some of the debris may be contaminated, so we need to be careful," shuttle program manager Ron Dittemore said.
Shuttles have long used a chemical called hydrazine to run their auxiliary power units. Hydrazine, a colorless liquid with an ammonia-like odor, is a toxic chemical and can cause harm to anyone who contacts it.
A water plant was closed in the Louisiana town of Many because of fears that toxic debris fell into the Toledo Bend reservoir along the Texas-Lousisiana line.
"To be safe rather than sorry we closed the water plant until further notice," Many Mayor Ken Freeman said.