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Michael Waalkes, Ph.D.

Senior Investigator

NTP Laboratory / Inorganic Toxicology Group


Building 101, Room E140
111 T.W. Alexander Drive
Research Triangle Park, NC 27709


Research Topics

Dr. Waalkes heads the Inorganic Toxicology Group within the NTP Laboratory. The mission of the Group is to characterize toxic responses to carcinogenic inorganics in order to elucidate mechanisms, particularly with regard to developmental basis of cancer in adulthood. A major focus is on arsenic with a smaller cadmium project. Inorganic carcinogens are major human hazards that impact millions of people world-wide. Characterizing mechanisms is key to defining risk and designing methods for intervention. Generally, cell models were used to define mechanisms in recently established or suspected human targets. A major focus with both arsenic and cadmium has become their impact on stem cells as a mechanism of carcinogenic action. The group also works on NTP Laboratory mission related projects that either involves metals or stem cells or other areas as required.


Michael P. Waalkes. Ph.D., is a Branch Chief with the Division of National Toxicology Program. He received his Ph.D. in 1981 in Pharmacology and Toxicology from West Virginia University, where he studied the perinatal toxicology of cadmium. He was a Postdoctoral Fellow at University of Kansas School of Medicine from 1981 to 1983 where he studied the cellular and molecular mechanisms of acquired tolerance to metal toxicity. In 1983 he joined the National Cancer Institute (NCI), where he became Chief of the Inorganic Carcinogenesis Section, which was part of the Laboratory of Comparative Carcinogenesis, NCI. From 1983 to 1996 he was located at the Frederick Cancer Research Center in Frederick, Maryland. In 1996 he and his section were detailed to Research Triangle Park to become NCI at the NIEHS where he was stationed until 2010 when he joined the DNTP at NIEHS to head up the NTP Laboratory. Waalkes received the Society of Toxicology Achievement Award for Outstanding Contributions to the Science of Toxicology by an Individual 41 Years of Age or Younger in 1990. In 2000 he received an NIH Merit Award for exemplary service as a member of the NIEHS, NTP Committee for the Report on Carcinogens (ROC). In 2007, Waalkes was awarded the Career Achievement Award for outstanding work in metals toxicology through the Society of Toxicology. Waalkes was the Editor-in-Chief of Toxicology and Applied Pharmacology, a leading journal in mechanistic toxicology, from 2000 to 2009 and serves on the Editorial Boards of multiple journals including as an Associate Editor of Environmental Health Perspectives. He has served on various review committees including those involving the International Agency for Research on Cancer, the NSF, various study sections, and the ROC. He is an active member of the Society of Toxicology (SOT) and is currently a senior Councilor. He also serves as Stem Cells Specialty Section President and has served on the Program Committee, the Board of Publications, the Committee on Public Communications, the Education Committee, and as Metals Specialty Section President and President of the North Carolina Regional Chapter. He has chaired numerous symposia and continuing education courses involving metals toxicology as the SOT annual meetings. Dr. Waalkes is author or co-author of over 350 publications.

Selected Publications

  1. Xu Y, Tokar EJ, Sun Y, Waalkes MP. Arsenic-transformed malignant prostate epithelia can convert noncontiguous normal stem cells into an oncogenic phenotype. Environ Health Perspect. 2012;120(6):865-71.
  2. Tokar EJ, Diwan BA, Ward JM, Delker DA, Waalkes MP. Carcinogenic effects of "whole-life" exposure to inorganic arsenic in CD1 mice. Toxicol Sci. 2011;119(1):73-83.
  3. Tokar EJ, Qu W, Liu J, Liu W, Webber MM, Phang JM, Waalkes MP. Arsenic-specific stem cell selection during malignant transformation. J Natl Cancer Inst. 2010;102(9):638-49.
  4. Kojima C, Ramirez DC, Tokar EJ, Himeno S, Drobná Z, Stýblo M, Mason RP, Waalkes MP. Requirement of arsenic biomethylation for oxidative DNA damage. J Natl Cancer Inst. 2009;101(24):1670-81.
This page was last updated on April 25th, 2013