Green green food colorings which has been approved by the US Food and Drug Administration. Chlorophyll, the E numbers E140 and E141, is the most common green chemical found in nature, and only allowed in certain medicines and cosmetic materials. Quinoline Yellow (E104) is a commonly used coloring in the United Kingdom but is banned in Australia, Japan, Norway and the United States. Green S (E142) is prohibited in many countries, for it is known to cause hyperactivity, asthma, urticaria, and insomnia. To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also
Barium "baryta", from Greek βαρύς ("barys"), meaning "heavy." "Baric" is the adjectival form of barium. Barium was identified as a new element in 1774, but not reduced to a metal until 1808 with the advent of electrolysis. Barium has few industrial applications. Historically, it was used as a getter for vacuum tubes and in oxide form as the emissive coating on indirectly heated cathodes. It is a component of YBCO (high-temperature superconductors) and electroceramics, and is added to steel and cast iron to reduce the size of carbon grains within the microstructure. Barium compounds are added to fireworks to impart a