The review and selection of substances and issues nominated for study is a multi-step process. A broad range of concerns are addressed during this process through the participation of representatives from NIEHS, other Federal agencies, the NTP Board of Scientific Counselors and the public. This multi-step evaluative process provides NTP with direction and guidance to ensure that its testing program addresses toxicological concerns relative to all areas of public health, and furthermore, that there is balance among the types of substances selected for study (e.g., industrial chemicals, consumer products, therapeutic agents). As such, it should be recognized that at any given time, the new study nominations under consideration do not necessarily reflect the overall balance of substances historically or currently being evaluated by NTP in its toxicology testing program.
Nominations are reviewed by the NTP Office of Nominations and Selection to determine whether the substance has been adequately tested or has been previously considered by NTP. For nominations not eliminated from consideration or deferred at this stage, the available information on the substance is examined in detail to prepare a Chemical Information Review Document that summarizes the relevant data for each substance. This Review serves as the supporting document of record for the nomination and addresses the types of information found in the NTP Study Nomination Elements. In some cases, supporting documents are prepared by the nominator and submitted along with the nomination.
To facilitate review of nominations by the NTP Board of Scientific Counselors (BSC) and the public, NTP staff develop draft research concept documents for each nomination recommended for in-depth study. A research concept is a brief document outlining the nomination or study rationale, and the significance, study approach, and expected outcome of a proposed research program tailored for each nomination. The purpose of these research concept documents is to outline the general elements of a program of study that would address the specific issues that prompted the nomination, but also encompass studies that may address larger public health issues, or topics in toxicology that could be appropriately addressed through studies on the nominated substance or issue. NTP shares draft research concepts with its partner agencies and invites their review.1
Nomination supporting documents, draft research concept documents, and any public comments received on the nominations are then presented to the NTP Board of Scientific Counselors for review and comment in a public meeting. This public meeting also provides and opportunity for NTP to receive additional public comments. The Board provides independent advice to NTP on the merit and priority of proposed studies for each nomination, and may suggest additional studies as well as offer their perspective on issues raised by public comments.
Each nomination selected for study is assigned to an NIEHS, FDA, or NIOSH staff scientist (project leader) who assesses the information compiled during the nomination review and selection process and other pertinent current information. Project leaders then assemble a Study Design Team composed of staff from NTP, NIEHS, and other government agencies to formulate a detailed study plan. The project leader may also conduct informal discussions with the nominator and other interested parties in the course of developing the study plan. In some instances the Study Design Team may recommend not pursuing study of particular substance due to technical difficulties in acquiring a suitable test material or in carrying out specific studies, or the existence of adequate outside testing. If a study is warranted, the project leader presents a detailed study proposal to an NIEHS/NTP Project Review Committee. All studies approved as a result of this process are then implemented as time and resources permit.