Cardiac glycoside specifically categorized based on the plant they are derived from, as in the following list. For example, cardenolides have been primarily derived from the foxglove plants "Digitalis purpurea" and "Digitalis lanata", while bufadienolides have been derived from the venom of the cane toad "Bufo marinus", from which they receive the “bufo” portion of their name. Below is a full list of plants from which cardiac glycosides can be derived. Cardiac glycosides affect the sodium-potassium ATPase pump in cardiac muscle cells to alter their function. Normally, these sodium-potassium pumps move potassium ions in and sodium ions out. Cardiac glycosides, however, inhibit
Radioactive contamination from the Rocky Flats Plant tests." As noted by Carl Johnson in Ambio, "Exposures of a large population in the Denver area to plutonium and other radionuclides in the exhaust plumes from the plant date back to 1953." Weapons production at the plant was halted after a combined FBI and EPA raid in 1989 and years of protests. The plant has since been shut down, with its buildings demolished and completely removed from the site. The Rocky Flats Plant was declared a Superfund site in 1989 and began its transformation to a cleanup site in February 1992. Removal of the plant and surface contamination was