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Your Environment. Your Health.

Office of Program Operations

The Office of Program Operations provides critical scientific, contract, and project management expertise necessary to support NIEHS Division of the National Toxicology Program (DNTP) research efforts. 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.

Staff members in the Office are responsible for the following functions:

  • Addressing specific requirements for DNTP testing and research projects by acquiring new or using established technical capabilities.
  • Advising DNTP staff on contract capabilities and toxicology study conduct.
  • Directing and managing the work of DNTP’s contract research organizations for conducting in vitro and in vivo toxicology studies and literature analysis projects.
  • Providing expertise, direction, and contract oversight for DNTP support functions of:
    • Absorption, distribution, metabolism, and excretion (ADME) and toxicokinetic studies and chemistry activities.
    • Data analysis, report preparation, review, and publication.
    • Health and safety, quality assessment.
  • Providing guidance and oversight for contract acquisition strategy, fiscal procedures, and interagency agreements to accomplish DNTP goals.
  • Receiving, tracking, maintaining, and disseminating DNTP documents and data for the DNTP public and internal websites.

The Office of Program Operations is organized into the following groups, which provide advice, services, and oversight to accomplish DNTP goals:

OPO scientists contribute to NTP report and monograph series and publish findings in the NIEHS report series and peer-reviewed scientific literature. Staff publications can be viewed on the webpage.


Michelle J. Hooth, Ph.D.
Michelle J. Hooth, Ph.D., D.A.B.T.
Acting Deputy Director for Program Operations, Division of NTP;
Director, Office of Program Operations
Tel 984-287-3140
Fax 919-541-4255
P.O. Box 12233
Mail Drop K2-07
Durham, N.C. 27709

Support Staff

Robbin Guy
Robbin Y. Guy
Program Specialist

Tel 984-287-3136
Fax 301-480-3009
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