Resisting oblivion: scientific criticism and legal possibilities concerning the discharges of radioactive water from Fukushima

Background Japan's ongoing discharge of treated radioactive wastewater from the Fukushima Daiichi Nuclear Power Plant, approved by the IAEA as consistent with international safety standards, has generated significant scientific and legal controversy. The safety justification relies on assumptions regarding TEPCO's ALPS treatment system effectiveness, monitoring reliability, data transparency, and minimal risks to marine ecosystems and human health. Methods This paper employs an interdisciplinary approach integrating marine science and international law. We categorize Japan and TEPCO's scientific justifications into four core claims and highlight the scientific uncertainties that weaken the strength of such claims. As part of this, we apply fundamental dose-calculation methods to estimate organ-specific absorbed and effective doses for key radionuclides (tritium, cesium-137, strontium-90) and their potential health impacts. We then systematically map identified scientific uncertainties to corresponding structural weaknesses in international legal accountability mechanisms. Results Our analysis reveals substantial uncertainties undermining Japan's safety claims. These empirical gaps systematically expose structural failures in international governance: absence of technology verification standards, lack of binding testing protocols, inadequacies in instantaneous concentration-based compliance frameworks, outdated safety standards, national control preventing independent verification, and weaknesses in the IAEA institutional architecture. Conclusions The systematic pattern where scientific uncertainties map onto legal gaps reflects a fundamental mismatch between current frameworks, which are designed for routine operations, and the unprecedented circumstances of the multi-decade discharges from Fukushima. We provide concrete scientific, legal, and policy recommendations targeting each identified vulnerability to prevent Fukushima from establishing a dangerous precedent for inadequately regulated ocean disposal.