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Your Environment. Your Health.

Systems Toxicology Branch

The Systems Toxicology Branch (STB) is one of five branches of the Division of the National Toxicology Program (DNTP) at NIEHS. DNTP is a team-based scientific organization, and its mission is to improve public health through development of data and knowledge that are translatable, predictive, and timely. Many STB projects support activities of the National Toxicology Program (NTP), an interagency partnership of the U.S. Food and Drug Administration (FDA), National Institute for Occupational Safety and Health (NIOSH), and NIEHS.

Branch scientists and postdoctoral trainees work closely with other DNTP researchers to lead multi-disciplinary, cross-divisional project teams to characterize the potential hazard posed by substances and circumstances on a variety of cancer and noncancer health-related effects, usually (but not always) using rodent models. These teams work collaboratively with scientists in other federal agencies, institutes, industry, and academia to carry out the goals of DNTP and NIEHS. Research products from these multidisciplinary projects include peer reviewed journal publications and NTP reports that are used worldwide to inform regulatory decision-making, which leads to programs, activities, and policies that promote health or lead to disease prevention.

Functions of the STB within this DNTP team science research model include the following:

  • Coordinate the design, interpretation, and reporting of outcomes from projects and toxicology studies designed to assess the potential impact of substances in the environment.
  • Collaborate across DNTP to use other applicable and experimental model systems and innovative approaches, including suitable ex vivo, in vitro, and integrated informatic analyses, to ensure and facilitate direct applicability and translation of knowledge to the human risk context, in a timely manner to stakeholders.
  • Innovate traditional guideline animal studies by designing them to effectively enable translation to understanding hazard and risk to humans from exposure to specific substances, and to integrate with emerging predictive nonanimal-based approaches.
  • Leverage and integrate the full breadth of DNTP's nonanimal modeling capabilities to ensure maximum utility of our animal studies for public health protective decision-making.
  • Serve as Project Leaders for the in vivo guideline-compliant testing program of the NTP.
  • Provide scientific oversight, management, and coordination of federal contracts for immunotoxicology and genetic toxicology, and interagency agreements with federal partners at NIOSH and FDA.
  • Provide scientific staff who serve in leadership and governance roles on DNTP Program Management Teams.
  • Provide subject matter experts and leaders for cross-divisional projects that use guideline-compliant in vivo toxicity studies to characterize exposures and hazards of substances under investigation at the cellular, organ, system, individual, and population levels.
  • Provide toxicological science expertise to DNTP projects in multiple disciplines including, but not limited to, carcinogenicity, immunotoxicology, developmental toxicology, genetic toxicology, reproductive toxicology, neurotoxicology, mixtures toxicology, and inhalation toxicology.

Acting Chief

Nigel J. Walker, Ph.D., D.A.B.T.
Nigel J. Walker, Ph.D.
Acting Chief, Systems Toxicology Branch
Tel 984-287-3204
Fax 301-451-5596
P.O. Box 12233
Mail Drop K2-02
Durham, N.C. 27709

Support Staff

Anna Lee Mosley
Anna Lee S. Mosley
Contractor — Operations Coordinator

Tel 984-287-3164
Fax 301-480-2862
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