Hazardous materials

Lead () is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal, denser than most common materials. Lead is soft, malleable, and has a relatively low melting point. When freshly cut or melted, it appears shiny silvery with a bluish tint, but tarnishes to dull gray on exposure to air. Lead has the highest atomic number of any stable element, and three of its isotopes are endpoints of major nuclear decay chains of heavier elements.

Radon is a chemical element; it has symbol Rn and atomic number 86. It is a radioactive noble gas and is colorless and odorless. Of the three naturally occurring radon isotopes, only Rn has a sufficiently long half-life (3.825 days) for it to be released from the soil and rock where it is generated. Radon isotopes are the immediate decay products of radium isotopes.

thumb|The Globally Harmonized System of Classification and Labelling of Chemicals|international pictogram for poisonous substances. The skull and crossbones has long been a standard symbol for poison.

thumb|right|upright=1.3|Demonstration of the explosive properties of three different explosives; four explosions are demonstrated. Three are conducted on a solid marble base, and one is conducted on the demonstrator's hand; each is initiated by a match.

In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism, agent or micro-organism that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.

thumb|Corrosion on exposed metal, including a bolt (fastener)|bolt and nut

chemical compound used to oxidize another substance

Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity). Sometimes the word is more or less synonymous with poisoning in everyday usage.

emission of subatomic particles by the decay of an atomic nucleus

waste materials that exhibit hazardous characteristics

ability to easily ignite in air at ambient temperatures

solids, liquids, or gases that can harm people, other living organisms, property, or the environment

biological material that poses serious risks to the health of living organisms

process of manufacturing and consuming nuclear fuel

Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the E- and Z-isomers, which differ with respect to the relative position of the methyl and formyl groups. The E-isomer is more common. This lachrymatory liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in organic synthesis. It occurs in a variety of foodstuffs, e.g. soybean oils.

waste material that is toxic

European directive

nontoxic or minimally toxic gas which can displace oxygen in breathing air

category of substances

chemical substance that is hazardous to humans or the environment

multilateral convention of the International Maritime Organization in 2009

chemical compound

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