Period 6 element devices though concerns about the element's toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in clinical environments in favor of alcohol-filled, galinstan-filled, digital, or thermistor-based instruments. It remains in use in scientific research applications and in amalgam material for dental restoration. It is used in lighting: electricity passed through mercury vapor in a phosphor tube produces short-wave ultraviolet light which then causes the phosphor to fluoresce, making visible light. Thallium is a chemical element with the symbol Tl and atomic number 81. This soft gray other metal resembles tin but discolors when exposed to air. The
Toxic Substances Control Act of 1976 Section 5(h)(3), and radioactive materials and wastes regulated by the Nuclear Regulatory Commission. The EPA reviews new chemical notifications and if it finds an "unreasonable risk to human health or the environment," it may regulate the substance from limiting uses or production volume to outright banning it. In 2013, the Frank R. Lautenberg Chemical Safety for the 21st Century Act was proposed as the first major overhaul in many years. The Toxic Substances Control Act of 1976 mandated the EPA to protect the public from "unreasonable risk of injury to health or the environment" by regulating the manufacture and sale