Integrating emerging science to improve estimates of risk to wildlife from chemical exposure: What are the challenges?

Many jurisdictions require ecological risk assessments for terrestrial wildlife (i.e., terrestrial vertebrates) to assess potential adverse effects from exposure to anthropogenic chemicals. This occurs, for example, at contaminated sites and when new pesticides are proposed, and it occurs for chemicals that are in production and/or proposed for wide-scale use. However, guidance to evaluate such risks has not changed markedly in decades, despite the availability of new scientific tools to do so. In 2019, the Wildlife Toxicology World Interest Group of the Society of Environmental Toxicology and Chemistry (SETAC) initiated a virtual workshop that included a special session coincident with the annual SETAC North America meeting and which focused on the prospect of improving risk assessments for wildlife and improving their use in implementing chemical regulations. Work groups continued the work and investigated the utility of integrating emerging science and novel methods for improving problem formulation (WG1), exposure (WG2), toxicology (WG3), and risk characterization (WG4). Here we provide a summary of that workshop and the follow-up work, the regulations that drive risk assessment, and the key focus areas identified to advance the ability to predict risks of chemicals to wildlife. Integr Environ Assess Manag 2024;00:1-13. (c) 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Emerging methods and science that support problem formulation, conceptualizing the problem relative to regulatory statute and management goals in wildlife ecological risk assessment, provide opportunities to improve accuracy and make sound environmental decisions. Development and use of a priori, scenario-based approaches, operationalization of animal-friendly techniques for exposure assessment, and establishment and implementation of postregistration, remediation, and/or restoration monitoring guidance will improve exposure assessment in wildlife risk assessment. Effect assessments for wildlife would benefit from addressing critical knowledge gaps in the sensitivity of amphibians, reptiles, and bats in addition to birds and mammals, and from further development of regulatory guidance on holistic effect assessment at individual and population level in wildlife. Development and implementation of weight of evidence approaches may help address uncertainty in risk characterization, which may be supported by developing probabilistic approaches and systematic reviews and improved evidence-integration techniques.