On November 27, 2012, the U.S. Environmental Protection Agency (EPA) released a document entitled The EDSP Universe of Chemicals and General Validation Principles, as well as the list of approximately 10,000 chemicals. According to EPA, the document is a supplement to the June 2012 EDSP Comprehensive Management Plan, which EPA intends to provide strategic guidance and outline critical activities that are planned for the Endocrine Disruptor Screening Program (EDSP) for the remainder of fiscal year (FY) 2012 through FY 2017. The EDSP Universe of Chemicals and General Validation Principles addresses chemicals that may be considered by the EDSP for screening and testing within the five year time horizon of the EDSP Comprehensive Management Plan. EPA states that, given the large number of chemicals that it regulates and that are potentially subject to EDSP screening, “it is important to strategically prioritize which chemicals should undergo screening so the chemicals with the greatest potential for interacting with the endocrine systems are evaluated in a timely manner to ensure public and wildlife protection.” To this end, according to EPA, the document describes general validation principles for the use of computational toxicology tools for efficient chemical prioritization. The document is available online. The list of chemicals is available online. Bergeson & Campbell, P.C.’s July 2, 2012, memorandum regarding the EDSP Comprehensive Management Plan is available online.
EPA developed the EDSP to meet the Federal Food, Drug, and Cosmetic Act’s (FFDCA) mandate “to determine whether certain substances may have an effect in humans that is similar to an effect produced by a naturally occurring estrogen, or such other endocrine effects as the Administrator may designate.” The FFDCA requires that all pesticide chemicals be screened, and gives EPA the authority to “provide for the testing of any other substance that may have an effect that is cumulative to an effect of a pesticide chemical if the Administrator determines that a substantial population may be exposed to such a substance.” Under the Safe Drinking Water Act (SDWA), EPA has the authority to require testing “of any other substance that may be found in sources of drinking water if the Administrator determines that a substantial population may be exposed to such substance.” EPA notes that, beyond testing and determining endocrine effects, FFDCA also directs EPA to take the following action: “In the case of any substance that is found . . . to have an endocrine effect . . . the Administrator shall, as appropriate, take action under such statutory authority as is available to the Administrator . . . to ensure the protection of public health.”
EPA states that, as defined by the FFDCA and SDWA, the universe of chemicals potentially targeted for testing under the current five-year time horizon of the EDSP Comprehensive Management Plan consists of approximately 10,000 unique chemicals, including approximately 6,000 drinking water contaminants, 1,000 pesticide active ingredients, and 5,000 inert ingredients, with some overlap among the lists. EPA stresses that the identification of these chemicals for potential EDSP screening “should neither be interpreted as a list of chemicals that will automatically be screened, nor as a list of chemicals with potential to interfere with endocrine systems of humans or other species. As such, the universe of chemicals identified for the EDSP should not be considered a list of ‘known’ or ‘likely’ endocrine disruptors.”
In considering this universe of chemicals, EPA intends to develop a prioritization scheme built on the broader, general concept articulated in the National Academy of Sciences Toxicity Testing in the Twenty-first Century: A Vision and a Strategy, which according to EPA speaks to the need to integrate all existing knowledge and multiple tools to generate a more practical, scientifically-based prioritized list of chemicals for EDSP screening. EPA states that the prioritization tools include the consideration of physicochemical properties, structure activity relationship, and high-throughput computational methods. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) will consider and review the scientific issues associated with prioritizing the universe of EDSP chemicals using computational toxicology tools during its January 29-February 1, 2013, meeting. Nominations of candidates to serve as ad hoc members of the SAP for this meeting are due November 30, 2012. EPA urges that written comments concerning the SAP meeting be submitted by January 15, 2013. More information regarding the SAP meeting is available online.
In the integrated prioritization scheme, EPA states that it intends to apply both exposure and effect-based methods and consider inherent chemical properties to formulate a process for prioritizing chemicals based on their likelihood to interact potentially with the endocrine system. According to EPA, some potential outcomes from this prioritization scheme may be to place certain chemicals on a low priority list for screening, because their physicochemical properties indicate a low likelihood for potential to interact with the endocrine system or cause systemic effects; or chemicals may be excluded from EDSP screening based on other factors. EPA expects consideration of these factors to prioritize further candidate chemicals and reduce the number of chemicals for Tier 1 screening under the EDSP to those with a higher potential probability of interacting with the endocrine system.
EPA notes that the universe of chemicals is not a static list of chemicals, but instead “represents a dynamic universe of chemicals that will change over time.” EPA will update the prioritization status of this universe of chemicals with the annual update of the EDSP Comprehensive Management Plan, and as new data become available.
EPA notes that the document “does not create or confer legal rights or impose any legally binding requirements on the EPA or any other party.” EPA distributed the document “solely for the purpose of sharing this information with the public, consistent with the EPA transparency objectives.” According to EPA, because it is not intended to serve any other purpose, and should not be construed to represent formal dissemination of any Agency determination or policy, “the information correction process under the agency’s Information Quality Guidelines does not apply to this document.”