Evidence-based toxicology like evidence-based medicine, provides scientifically grounded evidence-based conclusions as distinguished from authority-based opinions. As an example, we address a proposition from the US Environmental Protection Agency's (EPA) Draft Dioxin [2,3, 7,8-tetrachlorodibenzo-P-dioxin (TCDD)] reassessment that: ‘dioxin... can produce effects... at or near current background body burdens or intake levels’. Guided by a systematic, objective, and unbiased analysis of the available molecular, physiological, and clinical/epidemiologic data, in accordance with accepted principles of scientific logic, we reach the evidence-based conclusion that the proposition is rejected. When gaps in scientific knowledge necessitate formulation of opinions to meet preventive or precautionary goals, the reversion to authority should be explicitly acknowledged.
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