ID#

1072

Location:

Exhibit Hall

Time of Presentation:

March 11, 2003 - 1:30 p.m.

Category (Subcategory):

In Vitro/Alternative Animal Models, (Safety Evaluation), (Endocrine System)

ICCVAM Proposed Substances for the Validation of In Vitro Estrogen Receptor (ER) and Androgen Receptor (AR) Binding and Transcriptional Activation (TA) Assays
W.S. Stokes¹; B.S. Shane^1,2; C.J. Inhof^1,2; R.R. Tice^1,2;
D. Hatten³; M. Wind⁴
1. NICEATM, NIEHS, RTP, NC, USA;
2. ILS, Inc., RTP, NC, USA;
3. USFDA, Washington, DC, USA;
4. CPSC, Washington, DC, USA;

The U.S. EPAs proposed Endocrine Disruptor Screening Program (EDSP) includes a Tier 1 screening battery composed of in vitro and in vivo test methods designed to identify substances capable of interacting with the endocrine system. Prior to implementation of the EDSP, the component test methods must be adequately validated. An Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) and NICEATM expert panel evaluated the validation status of in vitro ER and AR binding and TA (agonist/antagonist) assays that might be included in the Tier 1 battery. The panel determined that none of the in vitro assays had been adequately validated. To facilitate the necessary validation studies, a common list of 78 proposed substances was compiled that addressed the panels recommendations. Substances were selected to ensure that reliability and accuracy of the in vitro assays would be adequately characterized across a broad range of chemical classes and responses. Selection criteria included quantity and quality of available data, potency, chemical class, selection for in vivo validation studies, and commercial availability. A minimum of 25% of the substances are known or expected to be negative in each of the different assay types. The use of a common substance list for validation will facilitate assessment of comparative assay performance, establishment of minimum performance criteria, and selection of acceptable in vitro test methods. Generation of both in vivo and in vitro data on many of these chemicals during future validation studies will also aid the future development of more predictive in vitro endocrine disruptor assays. Supported by NIEHS Contract N01-ES-85424. The views expressed above do not necessarily represent the official positions of any federal agency.

Please contact the NICEATM with questions about this abstract.