Sergei Y. Tolmachev, Ph.D.

Ph.D. in chemistry, Kyushu University

Master of Science in chemical engineering, Mendeleyev University of Chemical Technology of Russia


  • Health Physics Society
  • Radiation Research Society
  • Japan Health Physics Society
  • Society of Nuclear and Radiochemical Sciences (Japan)
  • European Radiation Dosimetry Group WG-7 on Internal Dosimetry

Additional Information
Sergei Y. Tolmachev is an associate research professor at the College of Pharmacy where he directs the U.S. Transuranium and Uranium Registries Research Center and the National Human Tissue Repository. These programs are funded through federal grants and provide long term follow up of actinide biokinetics and potential health effects in nuclear workers with accidental internal depositions of these elements. Prior to this position, Tolmachev managed the radiochemistry laboratory operations and research in the fields of actinide radiochemistry and mass spectrometry, in support of internal dosimetry and actinide biokinetics research.

Current grants
U.S. Department of Energy, USTUR: Five Decade Follow-up of Plutonium and Uranium Workers, PI.

U.S. Department of Energy, Manage and Operate U.S. Transuranium and Uranium Registries, PI.

Past grants
U.S. Department of Energy, Project 2.4 Mayak Worker Dose Reconstruction, PI

Health Protection England (UK), Plutonium Binding in the Upper Airways of the Human Respiratory Tract, PI

Selected Publications
Kathren RL, Tolmachev SY. Natural uranium tissue content of three Caucasian males. Health Physics 109: 187-197; 2015.

Avtandilashvili M, Puncher M, McComish SL, Tolmachev SY. US Transuranium and Uranium Registries case study on accidental exposure to uranium hexafluoride. Journal of Radiological Protection 35: 129-151; 2015.

Nielsen CE, Wang X, Robinson R, Brooks A, Lovaglio J, Patton K, McComish SL, Tolmachev SY, Morgan WF. Carcinogenic and inflammatory effects of plutonium-nitrate retention in an exposed nuclear worker and beagle dogs. International Journal of Radiation Biology 90: 60 - 70; 2014.

Lariviere D, Tolmachev SY, Kochermin V, Johnson S. Uranium bone content as an indicator of chronic environmental exposure from drinking water. Journal of Environmental Radioactivity 121: 98-103; 2013.

Nielsen CE, Wilson DA, Brooks AL, McCord SL, Dagle GE, James AC, Tolmachev SY, Thrall BD, Morgan WF. Microdistribution and long-term retention of 239Pu(NO3)4 in the respiratory tracts of an acutely exposed plutonium worker and experimental beagle dogs. Cancer Research 72: 5529-5536; 2012.

Lariviere D, Tremblay M, Durand-Jezequel M, Tolmachev S. Detection of beryllium in digested autopsy tissues by inductively coupled plasma mass spectrometry using a high matrix interface configuration. Analytical and Bioanalytical Chemistry 403: 409-418; 2012.

Tolmachev SY, Ketterer ME, Hare D, Doble P, James AC. The US Transuranium and Uranium Registries: Forty years’ experience and new directions in the analysis of actinides in human tissues. Proceedings in Radiochemistry - A Supplement to Radiochimica Acta 1: 173-181; 2011.

Kramer GH, Hauck B, Capello K, Rühm W, El-Faramawy N, Broggio D, Franck D, López MA, Navarro T, Navarro JF, Perez B, Tolmachev S. Comparison of two leg phantoms containing 241Am in bone. Health Physics 101: 248-258; 2011.

Hare D, Tolmachev S, James A, Bishop D, Austin C, Fryer F, Doble P. Elemental bio-imaging of thorium, uranium, and plutonium in tissues from occupationally exposed former nuclear workers. Analytical Chemistry 82: 3176-3182; 2010. (Featured Article, Webb S. MS maps actinides in exposed workers. Analytical Chemistry 82: 3409-3410; 2010).

Lynch TP, Tolmachev SY, James AC. Estimating 241Am activity in the body: comparison of direct measurements and radiochemical analyses. Radiation Protection Dosimetry 134: 94-101; 2009.

Selected Presentations
Uranium content, distribution, and biokinetics in human body. International Workshop on Uranium, Thorium, and Plutonium Sciences, Fukuoka, Japan, December 10, 2015. (invited)

Analysis of high-fired plutonium oxide and other actinides in MAPEP soil samples. 61th Radiobioassay and Radiochemical Measurements Conference. Iowa City, IA, October 25 – 30, 2015.

The National Human Radiobiology Tissue Repository. 1st International Workshop on Sample/Tissue Archiving of Radiobiology (STAR2015), Kyoto, Japan, May 24-25, 2015. (invited)

The National Human Radiobiological Tissue Repository: A unique resource for scientists. 60th Radiation Research Society Meeting, Las Vegas, NV, September 21-24, 2014. (invited)

USTUR case study on accidental exposure to uranium hexafluoride. 11th International Conference on Health Effects of Incorporated Radionuclides, Berkeley, CA, October 13-17, 2013.

Biokinetic modeling of chelation therapy for 241Am – USTUR Case 0846. 57th Annual Meeting of the Health Physics Society, Sacramento, CA, July 22-26, 2012.

The U.S. Transuranium and Uranium Registries: Beyond archiving. DoReMi/STORE Workshop on Sharing Data and Biomaterials from Radiation Science, Rome, Italy, January 25-26, 2012. (invited)

Radiochemistry Program at the U.S. Transuranium and Uranium Registries. Joint Symposium between Kyushu Environmental Evaluation Association and Kyushu University Radioisotope Center, Fukuoka, Japan, April 6, 2010. (invited)

updated 03/01/2016 Back to top

Director and
Associate Research Professor

United States Transuranium & Uranium Registries

1845 Terminal Dr. Suite 201
Richland, Wash.