Dr. Stewart received her PhD in industrial hygiene from Johns Hopkins University.   She worked at OSHA for 6 years and then moved to the National Cancer Institute (NCI) until she retired in 2006.  She has supported occupational epidemiology studies by assessing past exposures for chemical agents.  Her research included developing methods to improve exposure assessment methods in epidemiologic studies.  Currently, she is a contractor to the NCI (continuing her earlier work) and the National Institute for Environmental Health Sciences (NIEHS).  For the NIEHS she is leading the exposure assessment team for a study of the potential health effects of the workers involved in the cleanup of the Gulf of Mexico oil spill in 2010.  She has served as a member of the ACGIH Board of Directors, on organizing committees of several exposure assessment conferences and on governmental and international committees including the International Agency for Research on Cancer.  She has almost 200 publications and has mentored 14 Ph.D. students and postdoctoral fellows.  In 2010, she received the ACGIH Meritorious Award.