arsenic poisoning

Harmful effects of arsenic compounds (in pesticides, chemotherapy drugs, paints, etc.), most often from insecticide exposure. Susceptibility varies. Arsenic is believed to combine with certain enzymes, interfering with cellular metabolism. Symptoms of acute arsenic poisoning include nausea and abdominal pain followed by circulatory collapse. Acute exposure to the gas arsine causes destruction of red blood cells and kidney damage; chronic exposure causes weakness, skin disorders, anemia, and nervous-system disorders. Arsenic in urine and hair or nails is the key to diagnosis. Treatment involves washing out the stomach and promptly administering the antidote dimercaprol.

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Nonmetallic to semimetallic chemical element, chemical symbol As, atomic number 33. It exists uncombined in two stable (and several unstable) allotropes, one gray and one yellow, but is more often found in nature as the sulfide or oxide. The elemental form is used to form alloys of metals (especially lead), and certain semiconductors are made from crystals of gallium arsenide (GaAs). Arsenious oxide (arsenic trioxide or white arsenic, As₂O₃) is used in pesticides, as a pigment, and as a preservative of hides and wood; this is the poisonous “arsenic” (see arsenic poisoning) in detective stories. Arsenic pentoxide (As₂O₅) is also used in insecticides, herbicides, metal adhesives, and pigments.

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AS-204 was a Saturn IB Launch vehicle that is associated with two missions:

• Apollo 1 - Scheduled to be the first manned Apollo flight, but the crew was killed on the launch pad.
• Apollo 5 - The first test of the Apollo Lunar Module, which used the AS-204 rocket that was originally intended for Apollo 1.