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
Health and safety hazards of nanomaterials workers, disposal services, and others. This may require toxicological or other testing, and all data or information provided must be vetted by properly controlled testing The ISO/TR 13329 standard provides guidance specifically on the preparation of safety data sheets for nanomaterials. The National Institute for Occupational Safety and Health does not issue regulations, but conducts research and makes recommendations to prevent worker injury and illness. State and local governments may have additional regulations. The Environmental Protection Agency (EPA) regulates nanomaterials under the Toxic Substances Control Act, and has permitted limited manufacture of new chemical nanomaterials through the use of consent