Breaking the "Toxic Ignorance Cycles" that Hinder New Approach Method (NAM) Acceptance in Environmental Risk Assessment.

The environmental risk assessment community currently faces an existential dilemma. Policy mandates increasingly encourage transformation of the traditional risk assessment paradigm: a shift away from whole animal toxicity testing, toward New Approach Methodologies (NAMs). While NAMs offer a promising new means of (eco)toxicological knowledge production for decision-makers, uncertainty, ignorance, and risk related to their development, validation, and regulatory acceptance remain, limiting their adoption in practice. We offer a new perspective on this challenge, unpacking what uncertainty and ignorance in relation to NAM innovation means, and encouraging actors involved in NAM innovation to critically reflect on how uncertainty is currently used to justify regulatory nondecisions and inaction. We introduce the concept of the toxic ignorance cycle which we conceptualise as a "vicious cycle" of environment, health, and safety knowledge gaps, institutionalized ignorance, nondecision/inaction, and outdated (or unfulfilled) legal mandates for environmental protection. We also explore how toxic ignorance cycles can be broken through actions aimed toward addressing uncertainty, ignorance, and risk, which operationalise the precautionary principle and the Responsible Innovation (RI) framework. Our aim is to encourage precautionary, ethical, and reflective NAM innovation and regulatory adoption.