The Isotope Ratio Mass Spectrometry (IRMS) and Gas Chromatography/Mass Spectrometry (GC/MS) laboratories comprise the Stable Isotope Core Laboratory, which covers most of a floor within the CNRC building. The Stable Isotope Laboratory provides analytical equipment and expertise for a number of studies requiring measurement of isotopically enriched compounds from body fluids for the measurement of total daily energy expenditure, nutrient oxidation, mineral metabolism and metabolism of complex organic nutrients.

Volunteers are given special tracers containing stable isotopes.  Stable isotopes are safe, non-radioactive forms of common elements such as carbon, nitrogen and hydrogen that occur naturally in small amounts in the foods and water we consume every day.  Because they are unique and relatively rare, stable isotopes are an invaluable tool for studying the flow of nutrients through the human body.

Compounds containing stable isotopes can be identified and measured using a distinct feature: the molecular weight of a stable isotope-containing compound differs from that of the original compound.  Using special instrumentation called mass spectrometers, scientists use this weight difference to trace the stable isotopes as they travel through the body and appear in the breath, urine, blood and stool. Because these isotopes are non-radioactive, they are harmless and can be used in studies with infants and children as well as pregnant and nursing women.

This sophisticated technology and the Center's knowledgeable scientists have established the CNRC as an international leader in the use of stable isotopic tracers of minerals and other nutrients to assess nutrient needs.

Training in the use of stable isotopes is available to CNRC postdoctoral fellows and visiting scientists, who also have the opportunity to participate in CNRC research programs.