Nuclear wastewater release to the Pacific Ocean: An environmentally critical socio-scientific issue to promote students’ and teachers’ grasp of evidence

Socio-scientific issues (SSIs) can work as an effective mediator to promote secondary students and science teachers’ environmental and science learning. This study explores one of such SSIs: The controversy over Fukushima’s nuclear wastewater release (NWR) to the Pacific Ocean, characterized by expert disagreement on predicting associated environmental risks. Aimed at producing a theory informed articulation of the issue useful for instructional purposes, this study conducted a content analysis of NWR by employing the grasp of evidence (GOE) framework, particularly attending to risk-related statements extracted from publicly available digital news articles and supporting documents mostly produced over one week during the time the release plan was officialized. The GOE-informed analysis articulated the expert disagreement by identifying statements focused on managing, predicting, and communicating risks of radioactive wastewater release. The analysis revealed 41 knowledge claim codes derived from 263 statements. These claims addressed the trustworthiness of arguments for the released water’s safety from the four evidence dimensions: analysis, evaluation, interpretation, and integration. Additionally, 10 claim codes emerged from 50 statements addressing the sociopolitical and ethical aspects of dealing with risks. Analysis of speakers of the knowledge claims revealed two contrasting positions on the NWR, release advocates or skeptics, as well as their professional status and potential interest relations. Findings demonstrate how GOE can facilitate science students’ and teachers’ socio-scientific reasoning by fostering multidimensionally evaluative approaches to competing knowledge claims and their speakers so as to promote socially and ethically conscious grasp of the controversy over NWR. Discussions consider the potential applications of NWR for the SSI-based interdisciplinary environmental and science instructions in science methods courses and secondary science classrooms.