The Center for Alternatives to Animal Testing is an academic center affiliated with the Division of Toxicological Sciences in the Department of Environmental Health Sciences of the Johns Hopkins University Bloomberg School of Public Health.

 

Johns Hopkins School of Public Health

Abstract for TestSmart -- Endocrine Disruptors

From Science to Policy: What are the Potential Uses of Alternatives in Risk Assessment and Risk Management?

Paul A. Locke, JD, DrPH
Department of Health Policy and Management Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland

In recent years concerns have been voiced about the presence in the environment of compounds that affect the endocrine and other hormonal systems. These compounds, commonly referred to as "endocrine disruptors," pose potential risks to humans, wildlife and the ecosystem. In the late 1990s the United States Congress enacted legislation reflecting this concern. Among other things, the legislation required the United States Environmental Protection Agency (EPA or the Agency) to develop a screening program to help determine whether certain substances may be endocrine disruptors. In response to this legislation, EPA formed the Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC), and charged the Committee with providing advice on how to design a screening and testing program for endocrine disruptor compounds. The EDSTAC recommendations have been used by EPA to establish an Endocrine Disruptor Screening Program (EDSP).

The EDSP will utilize a tiered approach for determining whether a compound could have an effect similar to naturally occurring hormones. Compounds will be sorted and prioritized based on existing scientific information. After the sorting and prioritizing are completed, some compounds will enter "Tier 1" screening, which is designed to identify those substances that will interact with the endocrine system. "Tier 2" screening will confirm this potential and further characterize adverse effects. EPA is moving forward with the EDSP by (1) establishing a method for setting priorities for screening and (2) ensuring that the assays used in Tiers 1 and 2 are scientifically validated.* EPA is committed to minimizing the number of animals used in the EDSP and to incorporating alternative test methods, such as in vitro toxicology tests, whenever and wherever possible. The Agency has suggested that a flexible and iterative approach is appropriate in this area of emerging scientific research.

The EDSP appears to be a preparatory step before a formal risk assessment is taken or recommended. Those compounds that are indicated by the EDSP to have hormonal effects will most likely undergo a full risk assessment. Based on the conclusions of this risk assessment and social, economic and political factors it is possible that risk management activities will be recommended or taken to reduce exposure and minimize or eliminate potential harm. In both the EDSP and subsequent risk assessment activities, alternative tests could be potentially useful in (1) screening and prioritization; (2) Tier 1 and Tier 2 testing; (3) characterizing risk in a full risk assessment; (4) designing, recommending and implementing risk management strategies.

This presentation will review the EDSP, the risk assessment process and risk management and pose for discussion a series of questions regarding the utility and value of alternatives in both the science and policy arenas. As existing and new scientific information and techniques are discovered and applied, risk assessors and risk managers should be positioned to take advantage of them. Alternatives utilized in the EDSP could be helpful in other risk-related analyses.

* This summary of the EDSP is based on materials prepared by EPA and submitted to Congress. It is anticipated that other workshop presenters will address in detail EPA's current and future EDSP activities.