Period 6 element form, as an X-ray radiocontrast agent for imaging the human gastrointestinal tract. Soluble barium compounds are poisonous due to release of the soluble barium ion, and have been used as rodenticides. New uses for barium continue to be sought. It is a component of some "high temperature" YBCOsuperconductors, and electroceramics. The lanthanide or lanthanoid (IUPAC nomenclature) series comprises the fifteen metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. These fifteen elements, along with the chemically similar elements scandium and yttrium, are often collectively known as the rare earth elements. The informal chemical symbol Ln is
Sterling v. Velsicol Chemical Corp. Sterling v. Velsicol Chemical Corp. Sterling v. Velsicol Chemical Corp., 855 F.2d 1188 (6th Cir. 1988), was an environmental lawsuit filed by citizens of Hardeman County, Tennessee, led by Steven Sterling, who sued Velsicol Chemical Corporation for contaminating their water supply through improper disposal of toxic chemicals. In August 1964, Velsicol Chemical Corporation acquired of rural land in Hardeman County, Tennessee. Velsicol used the site as a landfill for by-products from the production of chlorinated hydrocarbon insecticides at its Memphis, Tennessee, chemical manufacturing facility. Before Velsicol purchased the landfill site and commenced depositing chemicals into the ground, it neither conducted