The Complex Nature of “No Effect”

By Edward D. Levin, Ph.D., Duke University (edlevin@duke.edu)   It is commonly assumed that chemical exposures below the minimum dose that cause observed adverse effects indeed have no effect. However, given that the subject under consideration is an integrated organism that uses highly-evolved interacting physiological systems to maintain homeostasis, the “no observed adverse effect” at … Continue reading The Complex Nature of “No Effect”