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Your Environment. Your Health.

Deputy Division Director for Research

National Toxicology Program Division - Associate Director's Office

Nigel J. Walker, Ph.D., D.A.B.T.
Nigel J. Walker, Ph.D.
Deputy Division Director for Research
Tel 984-287-3204
Fax 301-451-5596
P.O. Box 12233
Mail Drop K2-02
Durham, N.C. 27709

Nigel Walker, Ph.D., D.A.B.T., is the Deputy Director for Research for the Division of the National Toxicology Program (NTP) at the National Institute of Environmental Health Sciences (NIEHS), one of National Institutes of Health. In this capacity he works with the NTP Division Director in the formulation, coordination, implementation, management and oversight of activities necessary to carry out the scientific mission of NTP.

Walker' duties include; serving as one of the NTP senior scientists and science advisors to analyze NTP science requirements and help determine the best course of action within the Division’s scientific mission; review and clear NTP scientific proposals, project strategies and products; communication of  results and outputs of the NTP to the public and other researchers both within and out of the NIH; serving as the designated project officer for a multi-million dollar interagency agreement (IAA) between NIEHS and FDA and to liaise with counterpart FDA senior staff to provide overall oversight of the IAA, including evaluation and prioritization of research, budget management, and coordination between FDA and NIEHS to ensure the desired research programs meets NTP scientific objectives.

Walker received his B.Sc. in Biochemistry in England from the University of Bath and his Ph.D. in Biochemistry from the University of Liverpool. Following postdoctoral training in environmental toxicology at the Johns Hopkins School of Hygiene and Public Health in Baltimore Md., he moved to the NIEHS, where he has been since 1995. His research interests are environmental toxicology, quantitative dose response modeling and risk assessment, mixtures toxicology and nanotoxicology.

Scientific and Support Staff

Diane L. Spencer, M.S.
Diane L. Spencer, M.S.
Health Scientist
Tel 984-287-3190
Fax 301-451-5718
P.O. Box 12233
Mail Drop K2-14
Durham, N.C. 27709

Selected Publications

  • Sayers BC, Walker NJ, Roycroft JH, Germolec DR, Baker GL, Clark ML, Hayden BK, DeFord H, Dill JA, Gupta A and Stout MD. (2016) Lung deposition and clearance of microparticle and nanoparticle C60 fullerene aggregates in B6C3F1/N mice and Wistar Han rats following nose-only inhalation for 13 weeks. Toxicology 339, 87-96. [Abstract]
  • Dinse GE, Jusko TA, Whitt IZ, Co CA, Parks CG, Satoh M, Chan EK, Rose KM, Walker NJ, Birnbaum LS, Zeldin DC, Weinberg CR, Miller FW. (2016) Associations between Selected Xenobiotics and Antinuclear Antibodies in the National Health and Nutrition Examination Survey, 1999-2004. Environ Health Perspect. 124, 426-36. [Abstract]
  • Heindel JJ, Newbold RR, Bucher JR, Camacho L, Delclos KB, Lewis SM, Vanlandingham M, Churchwell MI, Twaddle NC, McLellen M, Chidambaram M, Bryant M, Woodling K, Costa GG, Ferguson SA, Flaws J, Howard PC, Walker NJ, Zoeller RT, Fostel J, Favaro C, Schug TT. (2015) NIEHS/FDA CLARITY-BPA Research Program Update. Reprod Toxicol. 58, 33-44. [Abstract]
  • Frawley R, DeVito M, Walker NJ, Birnbaum L, White K Jr, Smith M, Maynor T, Recio L, Germolec D. (2014) Relative potency for altered humoral immunity induced by polybrominated and polychlorinated dioxins/furans in female B6C3F1/N mice. Toxicol Sci. 139, 488-500. [Abstract]
  • Levine KE, Han L, McWilliams AC, Essader AS, Amato KE, Fernando RA, Browning DB, Greene LC, Ensor DS, Walker NJ, Robinson VG and Collins BJ. (2014) Characterization of an assortment of commercially available multiwalled carbon nanotubes. Microchim Acta 181, 171–179. [Abstract]
  • Lauby-Secretan B, Loomis D, Grosse Y, El Ghissassi F, Bouvard V, Benbrahim-Tallaa L, Guha N, Baan R, Mattock H, Straif K; International Agency for Research on Cancer Monograph Working Group-Cogliano VJ, Aronson K, Tryphonas H, Guo YL, Machala M, Bonefeld-Jørgensen EC, Vorkamp K, Cravedi JP, Le Bizec B, Narbonne JF, Esch H, Cocco P, Merletti F, Vermeulen R, Agudo A, Johansson N, Fiedler H, Hopf N, Glauert HP, Herbert RA, James MO, Ludewig G, Robertson L, Ruder A, Walker N, and Carpenter DO. (2013) Carcinogenicity of polychlorinated biphenyls and polybrominated biphenyls. Lancet Oncol. 14, 287-8. [Abstract]
  • Rider, C.V., Carlin, D.J., DeVito, M.J., Thompson, C.L. and , and Walker, N.J. (2013) Mixtures Research at NIEHS: An Evolving Program. Toxicology 313, 94-102, PMID: 23146757. [Abstract]
  • Abdel-Rahman, A., Anyangwe, N., Carlacci, L., Casper, S., Danam, R.P., Enongene, E., Erives, G., Fabricant, D., Gudi, R., Hilmas C.J., Hines, F., Howard, P., Levy, D., Lin, Y., Pfeiler, E., Thurmond, T.S., Turujman, S, and Walker, N.J. (2011) The Safety and Regulation of Natural Products Used as Foods and Food Ingredients. Toxicol. Sci. 123, 333-348. [Abstract]
  • Auerbach, S.S., Shah, R.R., Mav, D., Smith, C.S., Walker, N.J., Vallant, M.K., Boorman, G.A., and Irwin, R.D. (2010) Predicting the hepatocarcinogenic potential of alkenylbenzene flavoring agents using toxicogenomics and machine learning. Toxicol Appl. Pharmacol 243, 300-14. [Abstract]
  • Gopee NV, Roberts DW, Webb P, Cozart CR, Siitonen PH, Latendresse JR, Warbritton AR, Yu WW, Colvin VL, Walker NJ, Howard PC. (2009) Quantitative Determination of Skin Penetration of PEG-coated CdSe Quantum Dots in Dermabraded but not Intact SKH-1 Hairless Mouse Skin. Toxicol Sci. 111, 37–48. [Abstract]
  • Walker N.J. and Bucher, J.R. (2009) A 21st century paradigm for evaluating the health hazards of nanoscale materials?" Toxicol Sci. 110, 251-4. [Abstract]
  • Maynard, A.D, Aitken, R.J., Butz, T., Colvin, V., Donaldson, K., Oberdorster, G., Philbert, M.A., Ryan, J., Seaton, A., Stone, V., Tinkle, S.S., Tran, L., Walker, N.J., and Warheit, D.B. (2006). Safe handling of nanotechnology, Nature 444, 267-269. [Abstract]
  • van den Berg, M., Birnbaum, L., Denison, M., De Vito, M., Farland, W., Feeley, M., Fiedler, H., Hakansson, H., Hanberg, A., Haws, L., Rose, M., Safe, S., Schrenk, D., Tohyama, C., Tritscher, A., Tuomisto, J., Tysklind, M., Walker, N., and Peterson, R.E. (2006). The 2005 World Health Organization Re-evaluation of Human and Mammalian Toxic Equivalency Factors for Dioxins and Dioxin-like Compounds. Toxicol Sci. 93, 223-241. (** Cited more than 1000 times) [Abstract]
  • Walker, N. J., Crockett, P., Nyska, A., Brix, A., Jokinen, M. P., Sells, D. M., Hailey, J. R., Easterling, M., Haseman, J. K., Yin, M., Wyde, M. E., Bucher, J. R., and Portier, C. J. (2005). Dose-additive carcinogenicity of a defined mixture of "dioxin - like compounds". Environ Health Perspect 113, 43-48 [Abstract]
  • Toyoshiba, H., Yamanaka, T., Sone, H., Parham, F. M., Walker, N. J., Martinez, J., and Portier, C. J. (2004). Gene interaction network suggests dioxin induces a significant linkage between aryl hydrocarbon receptor and retinoic acid receptor beta. Environ Health Perspect 112, 1217-1224. [Abstract]
  • Wyde, M. E., Eldridge, S. R., Lucier, G. W. and Walker, N. J. (2001) Regulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin induced tumor promotion by 17 ß-estradiol in female Sprague-Dawley rats. Toxicol. Appl. Pharmacol. 173,7-17. [Abstract]
  • Walker, N. J., Portier, C. J., Lax, S. F., Crofts, F. G., Li, Y., Lucier, G. W. and Sutter, T. R. (1999). Characterization of the dose-response of CYP1B1, CYP1A1, and CYP1A2 in the liver of female Sprague-Dawley rats following chronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicol. Appl. Pharmacol. 154, 279-86. [Abstract]
  • Hayes, C. L., Spink, D. C., Spink, B. C., Cao, J. Q., Walker, N. J. and Sutter, T. R. (1996). 17 beta-estradiol hydroxylation catalyzed by human cytochrome P450 1B1. Proc. Natl. Acad. Sci. U. S. A. 93, 9776-9781. [Abstract]
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