Iodine-131 (usually in the chemical form of iodide) is a component of nuclear fallout, and is particularly dangerous owing to the thyroid gland's propensity to concentrate ingested iodine, where it is kept for periods longer than this isotope's radiological half-life of eight days.
Magma is composed of molten rock and is stored in the Earthâs crust. Lava is magma that reaches the surface of our planet through a volcano vent. Lava flow, Hawai. Courtesy of the U.S. Geological Society.agma is composed of molten rock and is stored in the Earthâs crust. Lava is magma that reaches the surface of our planet through a volcano vent. Lava flow, Hawai. Courtesy of the U.S. Geological Society.
The easiest way to define magma and lava: magma is molten rock that is still beneath the earth's crust. When magma reaches earth's surface, through a volcano or other openings in the earth's surface, it is still the same substance, but it is called lava.demonsheep87 Â· 9 years ago.y definition, magma becomes lava when it's erupted. When magma or lava cool, the minerals making up the molten soup begin crystallizing. The slower a magma cools, the larger its crystals grow.