A sole facility of its kind, the Pyeongsan uranium refinery in North Korea was recently reported to be discharging radioactive wastewater into the Ryesong River. Since the river’s downstream reaches become part of the Han River estuary, which connects to the Yellow Sea, the ecological impact of the discharge extends to a vast area of ocean in East Asia.
The process has likely been occurring for years. The Pyeongsan refinery was built around the early 2000s, and in 2019, South Korean media began to suspect its unclassified outflow of wastewater into the environment. Recent environmental data has strengthened the suspicion: remote sensing revealed an abnormal growth of algae sludge in the sedimentation tank of the refinery, approximately 8.7 times larger than its size in 2006. Moreover, a South Korean citizen reported that the radiation level on the west coast was about 28 times higher than normal sea-level cosmic radiation. Such data not only heightens the suspicion in Pyeongsan but also suggests a significant health and ecological threat to East Asia and beyond.
Radiation damages cells in living organisms and increases the likelihood of cancer, birth defects, and leukemia. Even a small amount of radioactive contamination could impact a substantial number of lives, like people who consume fish caught in East Asian seas. In fact, a North Korean defector attested to a rumor of North Korean soldiers who worked near the Pyeongsan refinery dying without external or internal injuries—most likely due to radiation poisoning. Therefore, a prompt investigation regarding the Pyeongsan allegation is necessary. However, the response has remained stagnant due to international barriers. The tension between the two divided countries, North and South Korea, has led to political discomfort, which underpins a lack of attention from neighboring countries and environmental regimes, hindering the evaluation of the current radiation leakage and the impending threat across East Asia.
A meaningful solution requires coordinated regional research. Each East Asian country should conduct domestic testing of radiation levels in its rivers and seas to identify possible spread from the Pyeongsan site. So far, only South Korea’s Nuclear Safety and Security Commission (NSSC) has released a report measuring radioactive nuclides around the Han River estuary. The study found uranium and cesium levels slightly below recent averages, suggesting no immediate abnormalities.
Although this response is promising, a single test is insufficient for the current extent of transboundary contamination; moreover, the test contains several methodological flaws. First, samples were taken only from the river surface, even though uranium and caesium can dissolve throughout the water column. A different approach could have taken water samples from various depths, as seen in the comparable study that collected samples at depths of 1m, 100m, and 200m. Moreover, the NSSC did not examine marine organisms, although radioactive elements can bioaccumulate through ingestion and respiration. Finally, the research excluded two core items, radium and polonium, which are classified as Group 1 carcinogens. As Dr. Jeong Yong-hoon, a professor in KAIST’s Department of Nuclear and Quantum Engineering, explained, “Wastewater from uranium and caesium refineries is mainly composed of substances such as radium and polonium, not uranium.” Dependence on a single test creates a deficient view due to unexpected mistakes. Therefore, the following tests are essential, as they continue to address gaps in previous tests.
While Pyeongsan’s contamination may feel distant, it parallels local environmental issues that demonstrate how pollution, once released, can persist despite cleanup efforts. A part of the thirty-two-mile-long Sudbury River lies just north of Concord Academy’s campus. Since mercury was discovered there in the 1970s, fishing and canoeing have continued, yet swimming and fish consumption remain unsafe. The mercury was released from the Nyanza Chemical Waste Site in Ashland, Massachusetts. Despite government remediation programs and community involvement, the river remains contaminated decades later.
This local example underscores the importance of early, transparent environmental monitoring and long-term accountability. Like the Sudbury River, the Ryesong River’s contamination shows how industrial pollution can outlast political cycles and continue affecting ecosystems and communities for generations. Both cases highlight that once pollutants enter shared waterways, remediation becomes exponentially more complex.