NDSLGL Leadership

Commanding Officer

Commander Katherine Dozier is a native of Petrolia, TX.  In 2004, she graduated from Angelo State University in San Angelo, Texas with a Bachelor of Science in Biochemistry.  In 2009, she received her Ph.D. in Biochemistry from Texas A&M University in College Station, Texas.  CDR Dozier was commissioned as a Lieutenant in the Medical Service Corps in November 2010 and completed Officer Development School in Newport, RI in April 2011.
In April 2011, CDR Dozier reported directly to her first duty station, the US Naval Academy (USNA) in Annapolis, Maryland, where she taught courses in chemistry, biology, and biological and chemical warfare agents.  In August 2014, CDR Dozier reported to the Navy Drug Screening Laboratory (NDSL), San Diego.  While at NDSL, San Diego, she served as the Deputy Director for Operations over Initial Screening, then as the Deputy Senior Officer. 
In October 2017, CDR Dozier was assigned to the Defense Health Agency Detachment - Armed Forces Medical Examiner System (AFMES), Division of Forensic Toxicology, Dover, Delaware, where she served as Chief, Special Forensic Toxicology Drug Testing Laboratory (SFTDTL) and a Forensic Toxicologist for the Human Performance/Postmortem Laboratory (HP/PM).  In February 2020, she filled the mission critical billet of Financial Administrative Officer, overseeing budget, contracting, and government purchase card programs.  In October 2020, CDR Dozier was selected to serve as Deputy Director, Division of Forensic Toxicology, and was subsequently named Director in March 2021.  In June 2022, CDR Dozier was slated for her first Executive Medicine tour as the Executive Officer of Navy Drug Screening Laboratory, Jacksonville.  She oversaw the DoD’s method development and instrument evaluation center.  In August 2025, she assumed command of Navy Drug Screening Laboratory, Great Lakes, and oversees the DoD’s largest forensic toxicology drug testing laboratory.

CDR Dozier’s military awards include the Meritorious Service Medal (1), Joint Service Commendation Medal (1), Navy and Marine Corps Commendation Medal (2), Joint Service Achievement Medal (1), and Navy and Marine Corps Achievement Medal (1). 

CDR Dozier is certified as a Fellow by the American Board of Forensic Toxicology (ABFT) and is the only Active Duty Naval Officer who currently holds that certification.  She has authored peer-reviewed articles and presented scientific talks at national conferences.  She also serves on the ABFT Board of Directors, ABFT Examination Committee and Society of Forensic Toxicologists Awards Committee. 
 

Executive Officer

Lieutenant Commander Dan Xu was commissioned as a Naval Officer in March 2017. Prior to her military service, she distinguished herself as a Lead Scientist at Stanford University School of Medicine, where she developed innovative in vivo and in vitro models for studying human-specific drug toxicity. Her research findings have been published in numerous high-impact journals, including PLOS Medicine, Cell Stem Cell, and the Journal of Pharmacology and Experimental Therapeutics.
LCDR Xu's initial assignment was to Naval Medical Research Unit - Dayton, located at Wright-Patterson Air Force Base. As Department Head of the Environmental Health Effects Laboratory, she directed research projects focused on assessing the toxicological effects of occupational and environmental exposures. LCDR Xu pioneered the application of stem cell technology to develop novel approaches for environmental exposure toxicity testing and evaluation, contributing to the protection of warfighters through advanced knowledge and technologies.
Subsequently assigned to NEPMU-7, LCDR Xu served as the Department Head of Threat Assessment, executing Force Health Protection missions across AFRICOM, EUCOM, and CENTCOM. She and her team focused on strengthening collaboration and engagement between DoD units, allied forces and host nations within these theaters, ensuring continuous DoD operations and regional readiness.
As a Service Chief Fellow at the Defense Advanced Research Projects Agency (DARPA), LCDR Xu facilitated dynamic collaboration between DARPA and BUMED, focusing on the intersection of healthcare and cutting-edge technology. Her efforts fostered Scientific & Technology advancements within Navy Medicine and the development of future Expeditionary Medicine platforms. Recognized as a Chemical, Biological, Radiological, and Nuclear (CBRN) Medical Defense Subject Matter Expert (SME) within the Navy, she served as a SME and reviewer for DARPA Biological Technology Office programs. She directly contributes to the strategic development of joint military research, technology, and military medicine.
In August 2024, LCDR Xu was appointed Executive Officer of the Navy Drug Screening Lab Great Lakes (NDSL GL). Overseeing a Command of 76 staff and managing an approximate $13 million annual budget, she directs and manages NDSL GL's daily operations, which include testing over one million urine specimens annually. Her leadership ensures the provision of scientifically valid and legally defensible test results for selected drugs of abuse and drug metabolites in urine specimens, delivered accurately and efficiently to the organization's clientele, ensuring DoD Drug Deterring Program’s success and warfighter’s readiness.
LCDR Xu's decorations include the Navy and Marine Corps Commendation Medal (two awards), the Navy and Marine Corps Achievement Medal (two awards), the Humanitarian Service Medal, and the Military Outstanding Volunteer Service Medal. She was also recognized as Officer of the Year 2020 (Biochemistry/Toxicology subspecialty) and Navy Medical Research & Development Enterprise Junior Officer of 2019