Kirschstein joined NIH in 1955. She studied
clinical pathology,
laboratory medicine, virally-induced cancer and developed the safety test for the
polio vaccines following the 1955
Cutter Incident, in addition to working on the safety of the measles vaccine. In 1972, Kirschstein became deputy director of the Division of Biologics Standards, a research division that was transferred from NIH to the
Food and Drug Administration, where she investigated the safety of the artificial sweetener
cyclamate. When she returned to the NIH in 1974, Kirschstein became the first woman to direct an institute when she was appointed the director of the National Institute of General Medical Sciences (NIGMS). At NIGMS, she raised the profile of the institute, persuading Congress to dramatically increase funding of basic medical science research. She also championed research training support, particularly for under-represented minorities, work that was recognized by the Congressionally-mandated renaming of the National Research Service Awards, as the Ruth L. Kirschstein National Research Service Awards. Kirschstein served as Deputy Director of the NIH under Dr. Harold Varmus, from 1993 to 1999. She served as Acting Director of the National Institutes of Health on two occasions, in 1993, and again from 2000-2002. ==Awards==