Endocrine

Concern about chemically mediated modulation of normal endocrine (hormonal) function in wildlife and humans has become a focal point of concern in the scientific community and the public as a whole. In 1996, the Food Quality Protection Act (section 408(p)) took action on this concern and directed the EPA to develop a screening program that would determine which chemicals may have hormone-altering effects. Based on this mandate, EPA's Endocrine Disruptor Screening Program (EDSP) was established. The program has involved research and development aimed at establishment of testing guidelines for aquatic and terrestrial organisms. Some of the guideline development work is still underway.

In 2009 EPA began issuing data call-ins (DCIs) for the first 67 chemicals to be scheduled for testing under the EDSP program. Over time, the program intends to cover all pesticide chemicals. The current list of chemicals designated for testing is available on EPA's website at: http://www.epa.gov/endo/pubs/regaspects/testorders.htm. The screening program is divided into a two-tiered design. Tier 1 consists of 11 screening assays for the potential of a specified chemical to interact with estrogen, androgen, or thyroid hormone systems. Tier 1 testing guidelines can be found at: http://www.epa.gov/scipoly/oscpendo/pubs/assayvalidation/tier1battery.htm. If a chemical tests positive for potential hormonal interactions under the Tier 1 phase, it is then scheduled for Tier 2 testing. Vertebrate animal testing begins under Tier 2, as described on the OPPTS website http://www.epa.gov/endo/pubs/assayvalidation/status.htm. Avian concerns are included in Tier 2, in the form of a proposed two-generation reproduction study.

Springborn's leading toxicology experts are participating in development of the testing guidelines for both Tier 1 and Tier 2 phases. Larry Brewer, Director, Avian/Wildlife Toxicology, is leading the avian toxicology department as we partner with other leading CROs to test various measurement endpoints under consideration for the current two-generation reproduction draft guideline (http://www.epa.gov/endo/pubs/edmvac/2gen_guide_gd_draft1.pdf). Ron Biever, Chief Scientific Officer, can assist clients with other EDSP questions regarding Tier 1 screening assays and fish testing guidelines proposed for Tier 2 testing. Springborn and Smithers Viscient are prepared to provide client services that meet all regulatory endocrine testing requirements. Smithers Viscient provides ecotoxicology testing and in vitro and in vivo toxicology services to the agricultural, pharmaceutical, and specialty chemical industries. Visit Smithers Viscient to download the video/audio recording of the Endocrine Disruptor Screening Program (EDSP) webinar, and download the EDSP white paper, titled "The Transparency Paradigm: How to select the right CRO for your Endocrine Disruptor Screening Program needs."

In addition to laboratory testing of potential endocrine disruptor chemicals, Springborn's Avian Toxicology Department has also developed field deployable techniques to monitor exposure of avian species to environmental estrogens. Both laboratory and field-deployable techniques have been developed to measure hormonal status in various measurable parameters from excreted hormones to mate selection and nesting behavior. Though the application of our own techniques are very broad and can be customized to fit a multitude of data needs, we welcome the opportunity to explore new and unique techniques as needed.