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Who We Are

Melissa A. McDiarmid, MD, MPH, DABT

Dr. McDiarmid is Professor of Medicine, Epidemiology and Public Health and Director of the University of Maryland School of Medicine’s Division of Occupational and Environmental Medicine where she teaches, sees patients, and directs a surveillance program for Gulf War Veterans.

Dr. McDiarmid received her B.A. degree from the University of Maryland Baltimore County, in Biological Sciences; her M.D. from the University of Maryland at Baltimore and her M.P.H. from The Johns Hopkins School of Public Health where she also completed fellowship training in Occupational Medicine. She is board-certified in Internal Medicine, Occupational Medicine and Toxicology.

Dr. McDiarmid was Director of the Office of Occupational Medicine for the U.S. Occupational Safety & Health Administration (OSHA) in Washington, D.C., a position she held from 1991 until 1996. From 1987 until moving to OSHA, she was Assistant Professor of Environmental Health Sciences at The Johns Hopkins School of Hygiene and Public Health where she directed the Occupational Medicine residency. She retains her Hopkins affiliation as an adjunct professor of Environmental Health Science.

Dr. McDiarmid has authored numerous journal articles and book chapters on occupational and environmental medicine topics related to: healthcare workers, medical surveillance and management, reproductive hazards, occupational cancers, and Gulf War environmental exposures.

Dr. McDiarmid's Faculty Profile


Lee-Ann Bennett, Administrative Assistant II

Lee-Ann Bennett is the Administrative Assistant II in the Division of Occupational and Environmental Medicine. She joined our department in the summer of 2018. Since then, she has played a key role in the daily operations of our department and works closely with the FPI Employee Health Program to manage all employee onboarding, scheduling and report management, amongst other duties.

Lee-Ann is pursuing her Bachelor of Science degree, majoring in Psychology with a minor in Health Services Management. Outside of work, Lee-Ann thoroughly enjoys traveling, cooking, walking on scenic nature trails and spending time with her family and friends.


Marianne Cloeren, MD, MPH

Dr. Cloeren is board-certified in both Occupational Medicine and Internal Medicine. After graduating from the University of Pennsylvania with a B.A., she attended Temple University School of Medicine, graduating with her M.D. in 1987, and then entered post-graduate training in Internal Medicine, followed by Occupational Medicine, in the Johns Hopkins system, where she earned a Master of Public Health in 1991. She has broad clinical experience, including primary care of Veterans, hospital medical service management, consulting, military occupational medicine and case management. 

Dr. Cloeren has a long-standing interest in medical education, in particular online training of clinicians, and in 2017 completed coursework at the University of Wisconsin - Stout, earning a Graduate Professional Development Certificate in Instructional Design. She has applied this training to develop an 8-hour continuing medical education course for the American College of Occupational and Environmental Medicine, called "Getting Your Patients Back to Work". Dr. Cloeren has particular interest and expertise in teaching medical providers how to make decisions that do not inadvertantly lead to prolonged work disability in their patients. She is also an experienced educator on the topic of opioid decision making, including clinical appropriateness, alternatives, informed decision making and monitoring. 

Dr. Cloeren is a leader in the American College of Occupational and Environmental Medicine, having served two terms on the Board of Directors, serving as past Chair and current member of the Council on Occupational and Environmental Medicine Practice, serving as current Chair of the special interest section on Work Fitness and Disability, and serving as a member of the Council on Education and Academic Affairs.

Dr. Cloeren joined the faculty in April 2017, and is the newest member of the Depleted Uranium Program, providing clinical surveillance related to potential adverse impacts of depleted uranium exposures in Veterans. 

Dr. Cloeren's Faculty Profile


Marian Condon, MS, RN

Marian Condon has a BSN from Johns Hopkins School of Nursing and an MS in Community/Public Health Nursing from the University of Maryland, School of Nursing. She has worked in the areas of environmental and occupational health and has given presentations and written articles on a variety of environmental and occupational health topics. She works as a VA employee on the Toxic Embedded Fragment Surveillance Center as well as the Depleted Uranium program with the Division of Occupational and Environmental Health at the University of Maryland, School of Medicine.


Joanna Gaitens, MSN, MPH, PhD

Dr. Gaitens is an Assistant Professor at the University of Maryland School of Medicine and serves as the Coordinator for the VA’s Toxic Embedded Fragment Surveillance Center and Registry which allows the VA to follow and manage the medical surveillance for veterans who have retained fragments from wounds received while serving in Iraq and Afghanistan.

Dr. Gaitens received her A.D.N. Degree from Norwich University in 1994; her BSN Degree from the University of New Hampshire in 1997; her MSN/MPH Degree from the Johns Hopkins School of Nursing and Bloomberg School of Public Health in 2000; and her PhD from the Johns Hopkins Bloomberg School of Public Health in 2006.

Prior to joining the University of Maryland faculty, Dr. Gaitens worked for several years as a nurse in skilled care before transitioning into public health. Her dissertation focused on the neurobehavioral effects associated with polychlorinated biphenyl exposure in older adults. She also has worked in the field of lead poisoning prevention.

Dr. Gaitens' Faculty Profile


Patricia Welsh Gucer, PhD

Dr. Gucer is an Assistant Professor at the University of Maryland School of Medicine. She is co-Principal Investigator on two studies examining safe resident lifting practices and their impact on caregiver injuries in long-term care facilities. She also works on a surveillance study of Gulf War Veterans exposed to depleted uranium.

Dr. Gucer received her A.B. Degree from Dumbarton College of Holy Cross in 1963, and her PhD from the Johns Hopkins University Department of Sociology in 2001.

Dr. Gucer has taught secondary school science, managed data for a longitudinal study of school children, and has been Baltimore Study Manager for a large multi-center clinical trial testing the effects of beta carotene on the incidence of lung cancer.

Dr. Gucer's Faculty Profile


Stella Hines, MD, MSPH

Dr. Hines, received her B.A. degree in Biochemistry in 1998 from Rice University; her MD from the Texas A&M University College of Medicine in 2002; and her Master of Science in Public Health (MSPH) in 2009 from the University of Colorado, Denver. She completed her residency in Internal Medicine at The University of Chicago in 2005, and fellowships in both Pulmonary & Critical Care Medicine and Occupational & Environmental Medicine at The University of Colorado, Denver in 2008 and 2009. She served as Instructor of Medicine at National Jewish Health in Denver from 2009-2010, in the Division of Environmental & Occupational Health Sciences, and served as the Medical Director of the Pulmonary Physiology Unit. During that time, she held academic appointments in the University of Colorado School of Medicine and the Colorado School of Public Health.

Dr. Hines is board-certified in Occupational Medicine, Pulmonary Medicine, Critical Care Medicine and Internal Medicine. She is a member of the American Medical Association, American College of Physicians, American Thoracic Society and the American College of Occupational and Environmental Medicine.

Dr. Hines joined the faculty at The University of Maryland in November 2010, with joint appointments in both the Division of Occupational and Environmental Medicine and the Division of Pulmonary & Critical Care Medicine, where she teaches, sees patients and serves as the Medical Director of Employee Health for the University Physicians Inc.

Dr. Hines’ research interests include pulmonary function and symptom analysis in occupational worker groups. She has participated in medical surveillance and studies of workers exposed to epoxy resins, artificial flavoring ingredients, coal, hard rock and uranium miners and workers exposed to beryllium. She has made invited presentations at local and international conferences and is a member of the Depleted Uranium program here.

Dr. Hines has been recognized for her teaching excellence, winning the coveted Golden Apple Teaching Award from the pre-clinical University of Maryland medical students. She has also been recognized by her peers as a Top Doctor in the field of Environmental/Occupational Health, winning this award from Baltimore Magazine two years in a row: 2016 and 2017. 

Dr. Hines' Faculty Profile


Marc Oliver, RN, MPH, MBA

Mr. Oliver is a research nurse and data analyst for the VA’s Depleted Uranium program and various research projects including collaborative work with NIOSH. Mr. Oliver does data management for the Employee Health program for the faculty practice of the University of Maryland School of Medicine.

Mr. Oliver received his A.D.N. Degree from Alfred State College in 1996; his MPH Degree from the Johns Hopkins Bloomberg School of Public Health in 1998 and his MBA from University of Maryland University College in 2005.


Gary Orr, MS, PE, CPE

Mr. Orr is a certified ergonomist and industrial engineer who collaborates with the division staff on assessments of workplace musculo-skeletal hazards and ergonomic and human factors interventions. He worked for OSHA on the development of the ergonomics standard, enforcement cases, outreach, and education. He has worked with the Joint Commission on the integration of ergonomics into the environment of care standards. He has assisted OSHA in the development of their ergonomics guidelines. He received a Bachelor's degree in Industrial Engineering from Auburn University and a Master's degree in Industrial Engineering/Human Factors from the University of Oklahoma.

Dr. Gary Orr's Faculty Profile


Tracy S. Roth, RN, BSN

Tracy is a research nurse on the Occupational Health team, where she organizes outreach programs, health education and the development of educational materials. She is the study coordinator for several University of Maryland medical surveillance programs.

Tracy received her Bachelor of Nursing Science degree in 1980 from the University of Bridgeport, Connecticut. She has worked in multiple clinical and public health settings. 


Sheila Williams, A.A.

Ms. Williams is our executive administrative assistant and focal point of the division. Before joining our program in 2000, she worked in health care for 10 years. Her wide variety of skills comes from working in such various environments as mental health, family preservation, and shelters for women, and administration. She provides executive assistance to the division faculty and staff while also serving our programs’ patients, clients and students.

Ms. Williams received her Executive Administrative Assistant A.A. Degree from Baltimore City Community College. She is currently pursuing her BS Degree in Human Resources Management from the University of Maryland University College.