Review of the Environmental Protection Agency's State-of-the-Science Evaluation of Nonmonotonic Dose-Response Relationships as they Apply to Endocrine Disrupters
View larger
  • Status: Final Book
  • Downloads: 1,417
Overview

Authors

Description

Potential health effects from chemicals that disrupt endocrine function pose an environmental health concern because of their ability to interfere with normal hormone function in human and wildlife populations. The endocrine system regulates biological processes throughout the body and is sensitive to small changes in hormone concentrations. Endocrine-disruptor research has focused primarily on chemicals that affect three hormone pathways that play important roles in reproduction and development - the estrogen, androgen, and thyroid hormone pathways. Some of this research has identified dose-response relationships that have nonmonotonic curves. Nonmonotonic dose-response curves (NMDRs) are of concern because they do not follow the usual assumption made in toxicology that as dose decreases the response also decreases.

The existence of NMDRs has been a controversial topic for decades, and there has been considerable debate about their implications for how chemicals are tested and for how risks from such chemicals are assessed. Toxicity tests are designed to identify hazards and to characterize dose-response relationships, so tests are aimed at finding a (high) dose that elicits a response, and dose-response is explored by testing lower doses spaced to identify statistically a no- or lowest-observed-adverse-effect level. The concern for NMDRs is that such studies, as currently designed, might not detect the inflection of the dose-response curve if only a few doses are tested or if the change in inflection occurs below the range of doses tested. Another concern is that some NMDRs are found for biological effects that are not usually evaluated in toxicity tests. If current testing strategies are inadequate to account for NMDRs, changes to risk assessment practices might be necessary. To help address these issues, the U.S. Environmental Protection Agency (EPA) developed a draft State-of-the-Science Evaluation: Nonmonotonic Dose Responses as they Apply to Estrogen, Androgen, and Thyroid Pathways and EPA Testing and Assessment Procedures. EPA asked the National Research Council to conduct an independent review of this evaluation to ensure that it is scientifically sound and of high quality.

Review of Environmental Protection Agency's State-of-the-Science Evaluation of Nonmonotonic Dose-Response as they Apply to Endocrine Disrupters evaluates whether EPA's evaluation presents a scientifically sound and high-quality analysis of the literature on NMDRs. This report reviews how well the EPA evaluation described how the assessment was performed, whether consistent methods and criteria were applied in the analysis of different evidence streams, and whether appropriate methods were applied to evaluating the evidence. The report makes recommendations to improve EPA's process and strengthen the evaluation.

Topics

  • Environment and Environmental Studies — Pollutants and Toxics
  • Environment and Environmental Studies — Policy, Reviews and Evaluations

Publication Info

66 pages | 6 x 9
Paperback
ISBN: 978-0-309-29754-7
Contents
Research Tools

Suggested Citation

National Research Council. Review of the Environmental Protection Agency's State-of-the-Science Evaluation of Nonmonotonic Dose-Response Relationships as they Apply to Endocrine Disrupters. Washington, DC: The National Academies Press, 2014.

Import this citation to:

Copyright Information

The National Academies Press (NAP) has partnered with Copyright Clearance Center's Rightslink service to offer you a variety of options for reusing NAP content. Through Rightslink, you may request permission to reprint NAP content in another publication, course pack, secure website, or other media. Rightslink allows you to instantly obtain permission, pay related fees, and print a license directly from the NAP website. The complete terms and conditions of your reuse license can be found in the license agreement that will be made available to you during the online order process. To request permission through Rightslink you are required to create an account by filling out a simple online form. The following list describes license reuses offered by the National Academies Press (NAP) through Rightslink:

  • Republish text, tables, figures, or images in print
  • Post on a secure Intranet/Extranet website
  • Use in a PowerPoint Presentation
  • Distribute via CD-ROM
  • Photocopy

Click here to obtain permission for the above reuses. If you have questions or comments concerning the Rightslink service, please contact:

Rightslink Customer Care
Tel (toll free): 877/622-5543
Tel: 978/777-9929
E-mail: customercare@copyright.com
Web: http://www.rightslink.com

To request permission to distribute a PDF, please contact our Customer Service Department at 800-624-6242 for pricing.

To request permission to translate a book published by the National Academies Press or its imprint, the Joseph Henry Press, please click here to view more information.

Related Books more

More by the Board on Environmental Studies and Toxicology more