Endocrine disruption: Where are we now: Tier 2 testing Mary Ann Ottinger Corresp., 1 , Kevin Flynn 2 , Sig Degitz 3 , Tim Verslycke 4 , Hank Krueger 5 , Leslie Touart 6 , Allen Olmstead 7 , Anne Goumelon 8 1 Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA 2 USEPA NHEERL MED, Duluth, Minnesota, USA 3 USEPA, Grantsburg, Wisconsin, USA 4 Gradient, Cambridge, Massachusetts, USA 5 Wildlife International Ltd., Easton, Maryland, USA 6 Equiparent Consulting, Woodbridge, Virginia, USA 7 Bayer CropScience, Research Triangle Park, North Carolina, USA 8 Organization for Economic Cooperation and Development, Paris, France Corresponding Author: Mary Ann Ottinger Email address:
[email protected] The focus of this session was on the proposed USEPA Endocrine Disruption Screening Program (EDSP) Tier 2 testing protocols. Tier 2 tests have been developed to evaluate the potential impacts of endocrine disrupting chemicals (EDCs) over the life cycle across organisms representing vertebrate and invertebrate classes. Key aspects of these Tier 2 testing protocols rely on selecting appropriate measurement end points to reveal differential sensitivity and adverse impacts across an organism’s life stages. To this end, certain Tier 2 tests utilize a multigenerational protocol, which detect both short- and long- term effects. However, multigenerational testing protocols can be time consuming and costly. As such, other testing protocols have also been considered, including partial life- cycle and extended one-generation tests. Regardless of the specifics of the multigenerational protocol, it is critical to identify key measurement end points that are responsive, reliable, and repeatable indicators of exposure to endocrine disrupting chemicals; these measures should also provide information to enable initial assessments of risk translated from individual to potential population level effects across a variety of living organisms.