Endocrine Disruption

In 1996, through the enactment of the Food Quality Protection Act (FQPA), the U.S. Congress directed EPA to screen pesticides for estrogenic activity in humans using validated assays or other scientifically relevant information (OSRI) and gave the Agency discretionary authority to screen for other endocrine effects. The Safe Drinking Water Act Amendments (SWDA) of 1996 authorized EPA to screen drinking water contaminants for similar activities.

To meet these requirements, EPA developed the Endocrine Disruptor Screening Program (EDSP), which uses a tiered approach to determine whether a substance may have an effect in humans that is similar to an effect produced by naturally occurring estrogen, androgen, or thyroid hormones. The core elements of the EDSP consist of: setting priorities for chemicals to be screened and tested, Tier 1 Screening using 11 in vitro and in vivo (mammalian and non-mammalian) validated assays, Tier 2 Testing (assays still under review) designed to encompass critical life stages and processes over a broad range of doses administered by a relevant route of exposure, and Hazard Assessment using both Tier 1 Screening and Tier 2 Testing data along with OSRI to characterize hazard. OSRI can also be used to provide EPA with relevant data to assess the need for further screening (Tier 1) and/or testing (Tier 2). At this time, the first list of chemicals identified and mandated by EPA have been screened in Tier 1 assays, and the data currently are being evaluated by the agency.  EPA has identified a second list of chemicals for Tier 1 Screening, with registrants currently anticipating the receipt of test orders.

ToxStrategies Consulting Services offers the scientific expertise to address endocrine disruption issues that include study design to address the role of endocrine disruption in the development of specific tumors, assay validation to assess endocrine disruption, and scientific oversight in which more than 20 test substances were screened using Tier 1 assays.  The professionals at ToxStrategies Consulting Services also have extensive industry and regulatory experience to assist clients with all aspects of EDSP, including:

  • Point of contact for consortia; implementation and oversight of program
  • Identification and critical review of peer-reviewed and regulatory study data for preparation and submission of “Other Scientifically Relevant Information” (OSRI)
  • Development of EDSP Tier I testing strategy
  • Dose and/or concentration selection for Tier I assays (design of dose-range-finding studies)
  • CRO assay placement and study monitoring; developing and tracking timelines
  • Submission of EDSP Tier 1 study data to EPA
  • Assessment of weight-of-evidence, using OSRI and Tier 1 data to evaluate the need for Tier 2 Testing
  • Design of studies to address data gaps to determine the need for Tier 2 Testing (provide OSRI)

For more information about our services, please contact us.