Progressing statistical analysis for regulatory ecotoxicology: developments, processes, and opinions

Statistical methods and computational tools applicable to ecotoxicology have developed and improved over recent decades, but regulatory risk assessments haven't kept pace, instead relying on outdated statistical methods and tools. Sessions in recent SETAC meetings dedicated to the development of statistical methods and tools for ecotoxicology have generated a high level of interest and discussion. Ecotoxicologists have expressed interest in the revision of the 2006 OECD document No. 54, "Current approaches in the statistical analysis of ecotoxicity data: a guidance to application" because they believe that the guidance is no longer reflective of contemporary statistical methods and tools; its revision is ongoing. Against this background, a call for papers for Special Series in IEAM was launched in autumn 2024 with manuscript submissions accepted until summer 2025. The purpose of this Special Series was to survey the statistical ecotoxicology landscape and reflect on recent developments, processes, and opinions. The editors of the Special Series welcomed and encouraged contributions and viewpoints from all employment sectors. The resulting series comprises eleven papers (seven original articles, three brief communications, and a workshop synthesis), with authors from academia, industry, government, and other research organizations. The series covers topics such as: recent progress in concentration-response modelling and hypothesis testing, including use of generalized linear models; strengths and weaknesses of established toxicity metrics (ECX, NOEC, BMD); application of toxicity metrics for species sensitivity distribution (SSD) modelling; added values of mechanistic effect modelling; and case studies highlighting opportunities and challenges related to the various statistical methods. This introductory paper aims to give an overview of the papers in the Special Series, summarizes their main topics and methods, and addresses further challenges to progress statistical analysis for regulatory ecotoxicology.