Resource Summary:The Consensus Key Characteristics Approach (CKCA) applied to carcinogens or endocrine disruptors is either: 1. Unscientific: as it cannot be falsified (all endogenous and biologically relevant chemicals are carcinogens and endocrine disruptors). OR 2. False: CKCA rewards confirmation bias. Evidence of meeting 1 single criterion is sufficient to be labeled a Carcinogen or Endocrine Disruptor. Proponents specifically state the following question should be answered: “Does exposure to the agent induce end points associated with one or more specific key characteristic properties of carcinogens?

Resource Summary:Regulatory WoE assessments are clear that GLY does not show EATS modalities. • The methodological deficiencies of KCs explain the incorrect classification of glyphosate’s potential as an ED using this novel approach compared to the application of wellestablished WoE approaches developed by regulatory agencies over the past decade. • ED KCs like other KCs have not been validated against negative controls and the GLY data is an ideal example of a negative control and demonstrates how the KC approach lacks a means to get to a negative conclusion about a chemical’s ED properties.

Resource Summary: For more than a decade, weight of evidence (WoE) evaluations have been the standard method for determining whether a chemical meets the definition of an endocrine disrupting chemical (EDC). WoE methods consider all data pertinent to satisfying the EDC definition and evaluating those data with respect to relevance, reliability, strength, and coherence with established endocrine physiology and pharmacology. A new approach for identifying EDC hazards has been proposed that organizes and evaluates data according to ten so-called “Key Characteristics (KCs) of EDCs”.

Resource Summary: - The KCs for EDCs were developed based on KCs for carcinogens. - Flaws in the KC approach for carcinogens have not been addressed or corrected and were repeated in the KCs for EDCs. - The KC approach requires less data and fewer resources than the WoE approach but lacks the basic elements of rigor and reproducibility that should be a standard requirement for regulatory science.