Chemical Selection Approach for Initial Tier 1 Screening
Approach for Selecting the Initial List of Chemicals for Screening - Federal Register Notice [PDF file, 17pp., 125KB, About PDF]
On this page:
- Overview of the EDSP
- Chemical Selection – Approach for Initial Screening
- Subsequent Approaches for Chemical Selection
- Initial List of Chemicals
The EDSP was established in response to a Congressional mandate in the Federal Food, Drug, and Cosmetic Act (FFDCA) to screen pesticides for their potential to affect the estrogen system. The core elements of the EDSP are:
- Assay development and validation;
- Selection of chemicals to be tested (i.e., the 2005 Federal Register Notice (PDF) (17 pp, 125K, About PDF); and
- Development of program policies and procedures to implement screening.
The approach used by EPA for selecting 50 to 100 chemicals for initial screening under the Federal Food, Drug and Cosmetic Act is summarized below. Nothing in the approach for selecting the initial list would provide a basis to infer that any of the chemicals selected for the list interferes with or is suspected to interfere with the endocrine systems of humans or other species.
The approach included consideration of the most current databases and priority-setting tools available. For this approach EPA:
- Focused chemical selection for this initial list on the subset of chemicals for which testing is required (i.e., pesticide chemicals);
- Used exposure data as the primary basis for chemical selection;
- Deferred consideration of nominations from the public;
- Excluded mixtures; and
- Excluded chemicals that are no longer produced or used in the United States.
The approach described in the September 2005 Federal Register notice further indicated that the following would be excluded from the list of chemicals for initial screening.
- Substances anticipated to have low potential to cause endocrine disruption (e.g., most polymers with number average molecular weight greater than 1,000 daltons, strong mineral acids, and strong mineral bases);
- "Positive control" chemicals used by EPA for the validation of the screening assays proposed for the Tier 1 battery.
EPA anticipates that it may modify its chemical selection approach for subsequent screening lists based on experience gained from the results of testing of chemicals on the initial list, the need for a broader approach in the future to incorporate different categories of chemicals (e.g., non-pesticide substances) and additional pathways of exposure, and the availability of new priority-setting tools (e.g., High Throughput Pre-Screening (HTPS) or Quantitative Structure Activity Relationship (QSAR) models). In addition, the Agency intends to conduct a review of the data received from the screening to evaluate whether the program could be improved or optimized.
EPA published the draft list of initial pesticide active ingredients and pesticide inerts to be considered for screening under the Federal Food, Drug and Cosmetic Act for public notice and comment in a 2007 Federal Register Notice (PDF) (18 pp, 131K, About PDF). The draft list was produced using the approach described in the September 2005 Federal Register Notice (PDF) (17 pp, 125K, About PDF), and included chemicals that the Agency decided should be tested first, based upon exposure potential.
On April 15, 2009, EPA published the Final List of Initial Pesticide Active Ingredients and Pesticide Inert Ingredients to be Screened under the Federal Food, Drug, and Cosmetic Act (PDF) (7 pp, 62KB, About PDF). The final list includes 67 chemicals to be screened under Tier 1 of the program. More information about the final list.
This list should not be construed as a list of known or likely endocrine disruptors. Nothing in the approach for generating the initial list provides a basis to infer that any of the chemicals selected interfere with or are suspected to interfere with the endocrine systems of humans or other species.