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Hormesis and Risk Assessment

Issues Relevant to Toxicology

  1. Edward J. Calabrese PhD Professor of Toxicology1,
  2. Paolo F. Ricci PhD, JD Professor of Risk Assessment2

Published Online: 15 DEC 2009

DOI: 10.1002/9780470744307.gat123

General, Applied and Systems Toxicology

General, Applied and Systems Toxicology

How to Cite

Calabrese, E. J. and Ricci, P. F. 2009. Hormesis and Risk Assessment. General, Applied and Systems Toxicology. .

Author Information

  1. 1

    University of Massachusetts, Department of Public Health, Environmental Health Sciences, Massachusetts, USA

  2. 2

    University of San Francisco, Harney Science Center, San Francisco, California, USA

Publication History

  1. Published Online: 15 DEC 2009


The hormetic dose-response model has experienced a strong resurgence of interest in toxicology, risk assessment and pharmacology. This is based on its capacity for validation, reproducibility, generalizability, and its demonstrated ability to predict low-dose responses far more accurately than threshold and linear-at-low-dose models. This paper assesses capacity of hormesis models to impact the current risk assessment process, as well as the implications for risk assessment if regulatory agencies were to accept the hormetic dose-response as the default model.


  • hormesis;
  • biphasic;
  • dose-response;
  • adaptive response;
  • risk assessment;
  • U-shaped;
  • J-shaped