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Your Environment. Your Health.

Kristen R. Ryan, Ph.D.

Systems Toxicology Group

Kristen R. Ryan, Ph.D.
Kristen Ryan, Ph.D.
Tel 984-287-3179
530 Davis Dr
Keystone Building
Durham, NC 27713

Kristen Ryan, Ph.D., DABT, is a toxicologist in the Toxicology Branch of the Division of National Toxicology Program (NTP) at the National Institute of Environmental Health Sciences. As a study scientist, Ryan collaborates with members of the Toxicology Branch as well as various intramural and extramural partners to investigate the safety of chemical agents nominated to the NTP toxicity testing program. Her primary responsibilities are to design and coordinate studies to evaluate the potential toxicity and carcinogenicity of various agents. In addition, she is responsible for communicating study results by peer-reviewed publication in NTP Technical Reports and manuscripts in scientific journals. Ryan is the currently the project leader for NTP studies of tris(chloropropyl)phosphate, echinacea, hydroxyurea, and ionic liquids. She also is a project coordinator for AIDs research studies, algae bloom toxins, and zebrafish-related research (SEAZIT).

Ryan's research interests include examining the relationship between exposure to various chemicals in the environment and developmental neurotoxicity or neurodegeneration. She participates in activities to enhance neurotoxicity testing within the NTP through protocol design and interpretation of large-scale animal studies. Additionally, Ryan has interest in alternative animal testing models for the prioritization and prediction of potential neurotoxic agents.

Ryan received a B.S. in Biology from the University of Pittsburgh in 2004 and in 2012 Ryan obtained her Ph.D. in Toxicology from the University of Colorado investigating the role of mitochondrial oxidative stress and dysfunction in progressive neurological disorders such as Parkinson's disease and Temporal Lobe Epilepsy. Upon completion of her graduate work, she obtained a post-doctoral IRTA fellowship at the NTP.

Selected Publications

  • Waidyanatha S, Ryan KR, Sanders M, McDonald JD, Wegerski C, Doyle-Eisle M, Garner J. 2018. Disposition of β-N-methylamino-L-alanine (BMAA), a potential neurotoxicant, in rodents following a single or repeated oral exposure. Toxicology and Applied Pharmacology, 339:151-160. [Abstract]
  • Sirenko O, Grimm FA, Ryan KR, Iwata Y, Chiu QA, Parham F, Wignall JA, Anson B, Cromwell EF, Behl M, Rusyn I, Tice RR. 2017. In vitro cardiotoxicity assessment of environmental chemicals using an organotypic human induced pluripotent stem cell-derived model. Toxicology and Applied Pharmacology, 322:60-74. [Abstract]
  • Ryan KR, Cesta MF, Herbert R, Brix A, Cora M, Witt K, Kissling G, Morgan DL. 2016. Comparative pulmonary toxicity of inhaled metalworking fluids in rats and mice. Toxicol Ind Health. Jun 23. pii: 0748233716653912. [Epub ahead of print] [Abstract]
  • Ryan KR, Sirenko O, Parham F, Hsieh JH, Cromwell EF, Tice RR, Behl M. 2016. Neurite outgrowth in human induced pluripotent stem cell-derived neurons as a high-throughput screen for developmental neurotoxicity or neurotoxicity. Neurotox. Mar;53:271-81. [Abstract]
  • Waidyanatha S, Ryan KR. 2014. Disposition of fragrance ingredient [14C]1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone in male Fisher rats following oral administration and dermal application. Xenobiotica. Aug;44(8):749-56. [Abstract]
  • Ryan K, Liang LP, Rivard C, Patel M. 2014. Temporal and spatial increase of reactive nitrogen species in the kainate model of temporal lobe epilepsy. Neurobiol Dis. Apr;64:8-15. [Abstract]
  • Ryan K, Backos DS, Reigan P, Patel M. 2012. Post-translational oxidative modification and inactivation of mitochondrial complex I in epileptogenesis. J Neurosci. Aug 15;32(33):11250-8. [Abstract]
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