Poster #19 - Beyond the 90-Day Clock: Temporal Governance in the EPA’s New Chemicals Program

• In Event: Saturday Poster Luncheon

Abstract

Regulatory performance under the U.S. Toxic Substances Control Act (TSCA) is commonly evaluated in terms of efficiency—how quickly agencies complete statutory reviews relative to mandated timelines. Section 5 of TSCA requires the U.S. Environmental Protection Agency (EPA) to review new chemical notices within a nominal 90-day window, yet review durations vary widely, with persistent backlogs and exceptionally long cases documented by oversight bodies. Existing explanations typically attribute delay to staffing shortages, workload, or scientific complexity. This paper advances an alternative perspective: regulatory time itself is a mode of governance through which uncertainty, coordination, and institutional accountability are actively managed. The study examines how review time is produced and distributed within TSCA §5 “not likely to present an unreasonable risk” (NLUR) determinations between 2016 and 2024. NLUR cases provide a controlled analytic setting because they share a common decisional endpoint while varying substantially in internal workflow structure. Using a novel, hand-constructed dataset of 396 cases derived from EPA records and docketed assessment documents, the analysis reconstructs internal timelines for front-end mobilization (acceptance to assessment start), assessment activity, decisional closure, and assessment concurrency across three administrative–interpretive policy eras. The research employs nonparametric distributional analysis (Kruskal–Wallis and pairwise Wilcoxon tests), correlation analysis, and a new “mean shrinkage” framework that translates descriptive differences into interpretable measures of organizational reconfiguration. Review duration is decomposed into aggregate, coordination-sensitive metrics and component-level scientific task durations (human health, environmental health, and environmental fate assessments). Results show that variation in total review duration is driven primarily by organizational timing and coordination, not by changes in the length of individual scientific assessments. Component-level assessment durations remain statistically stable across policy eras, while acceptance delays, assessment overlap, and decisional closure times vary significantly. A middle policy era (2020–2021) exhibits pronounced temporal compression characterized by higher concurrency and rapid closure without shortening individual assessments. A later era maintains high concurrency but shows renewed expansion and heavy-tailed delay, indicating limits to temporal control under tighter interpretive standards. The findings reframe regulatory efficiency as temporal reliability rather than speed. Policy reforms reallocate where time and uncertainty are absorbed within the workflow, rather than uniformly accelerating review. By quantifying how much organizational reconfiguration would be required for one regime to operate like another, the study provides a grounded basis for debates over realistic timelines, backlog reduction, and accountability in chemical risk regulation. The paper contributes a novel dataset, a replicable temporal decomposition framework, and a governance-focused interpretation of regulatory delay relevant to policy design and evaluation.

Author

• Aditi Chaturvedi, University of Delaware
  Presenting Author