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Food and Drug Administration

(Encyclopedia)Food and Drug Administration (FDA), agency of the Public Health Service division of the U.S. Department of Health and Human Services. It is charged with protecting public health by ensuring that foods...

saturation, of an organic compound

(Encyclopedia)saturation, of an organic compound, condition occurring when its molecules contain no double or triple bonds and thus cannot undergo addition reactions. For example, ethane (H3C–CH3) is a saturated ...

Sabatier, Paul, French organic chemist

(Encyclopedia)Sabatier, Paul, 1854–1941, French organic chemist, D.Sc. Collège de France, 1880. He joined the faculty at the Univ. of Toulouse in 1882 and taught there until he retired in 1930. Sabatier was a co...

gem, ornamental mineral or organic substance

(Encyclopedia)gem, commonly, a mineral or organic substance, cut and polished and used as an ornament. Gems also are used as seals (items of assurance) and as talismans (good-luck charms). For birthstones, see mont...

metabolism

(Encyclopedia)metabolism, sum of all biochemical processes involved in life. Two subcategories of metabolism are anabolism, the building up of complex organic molecules from simpler precursors, and catabolism, the ...

harvestman

(Encyclopedia)harvestman, arachnid, often called daddy longlegs because of its eight long, slender legs. The harvestman has a rounded or oval body possessing glands that give off an acrid scent. Its food consists o...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

polychlorinated biphenyl

(Encyclopedia)polychlorinated biphenyl or PCB, any of a group of organic compounds originally widely used in industrial processes but later found to be dangerous environmental pollutants. Polychlorinated biphenyl i...

polybrominated biphenyl

(Encyclopedia)polybrominated biphenyl or PBB, any of a group of organic compounds used as a fire retardant. In 1973 several thousand pounds of PBB were accidentally mixed with livestock feed that was later distribu...

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