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This is the list of extremely hazardous substances defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. § 11002).The list can be found as an appendix to 40 CFR 355. [1]
Toxic: a chemical that has a median lethal concentration (LC 50) in air of more than 200 parts per million (ppm) but not more than 2,000 parts per million by volume of gas or vapor, or more than 2 milligrams per liter but not more than 20 milligrams per liter of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats ...
Tetraethyl lead is one of the most significant heavy metal contaminants in recent use. [ 15 ] Toxic metals are found naturally in the earth, and become concentrated as a result of human activities, or, in some cases geochemical processes, such as accumulation in peat soils that are then released when drained for agriculture. [ 16 ]
Uranium is the 48th most abundant element in the Earth’s crust. [60] The decay of uranium, thorium, and potassium-40 in Earth's mantle is thought to be the main source of heat [61] [62] that keeps the Earth's outer core in the liquid state and drives mantle convection, which in turn drives plate tectonics.
Metal toxicity or metal poisoning is the toxic effect of certain metals in certain forms and doses on life.Some metals are toxic when they form poisonous soluble compounds. . Certain metals have no biological role, i.e. are not essential minerals, or are toxic when in a certain for
Mercury poisoning is a type of metal poisoning due to exposure to mercury. [3] Symptoms depend upon the type, dose, method, and duration of exposure. [3] [4] They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashes, anxiety, memory problems, trouble speaking, trouble hearing, or trouble seeing. [1]
Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive elements found in the environment, such as uranium, thorium and potassium and any of their decay products, such as radium and radon. [1]
The alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra) are the second most reactive metals in the periodic table, and, like the Group 1 metals, have increasing reactivity with increasing numbers of energy levels. Beryllium (Be) is the only alkaline earth metal that does not react with water or steam, even if the metal is heated red hot. [9]