Assuring the purity of drinking water in the nation's 250,000 public water systems will be easier with a new standard reference material (SRM) developed at the National Bureau of Standards (NBS).
SRM 1643, Trace Elements in Water, was prepared by using highpurity water and 23 elements to simulate the elemental composition of natural freshwater. Seventeen elements have been certified in concentrations at the nanogram per gram (part per billion) level. They are silver, aluminum, arsenic, beryllium, cadmium, cobalt, chromium, copper, iron, molybdenum, manganese, nickel, lead, selenium, strontium, vanadium, and zinc. The concentrations of two others, barium and mercury, are not certified, but are listed for information only.