Long-Range Transboundary Transport of Iodine-129 from South Asia to the Southern Tibetan Plateau Revealed by Moss and Lichen

作者：Luyuan Zhang, Peng Cheng, Xiaolin Hou, Dongbing Wang, Xuke Liu, Qi Liu, Guocheng Dong, Jie Zhou, Huang Jiang, Lu Tang · 发表于：Environmental Science & Technology Letters · 年份：2024 · DOI：10.1021/acs.estlett.4c00058 · 被引用次数：12 · 研究领域：Radioactive contamination and transfer、Lichen and fungal ecology、Radioactivity and Radon Measurements

Level and transport regime of radioactive pollutants are scarcely understood at the remote high-altitude Tibetan Plateau (TP), which is the well-known third pole. Radioactive 129 I is a major fission product, highly volatile, spreads globally and is, therefore, a perfect tracer of human nuclear contamination. Atmospheric levels of 129 I were investigated by mosses and lichens from the southern Tibetan Plateau (STP). 129 I levels of (203 ± 274) × 10 6 atoms/g and (175 ± 142) × 10 –10 for 129 I/ 127 I atomic ratios were first presented in the STP, considerably greater than the prenuclear level, but 2–4 orders of magnitude lower than the areas surrounding Indian and European nuclear fuel reprocessing plants (NFRPs). 129 I discharge history in combination with the wind field analysis indicates that Indian NFRPs are the primary sources of 129 I in the STP, and the Indian summer monsoon played a crucial interactive role in transporting airborne radioactive pollutants from South Asia to the STP interior. The spatial distribution of 129 I and 127 I in lichens distributed across Mt. Galongla reveals that the Yarlung Zangbo Grand Canyon serves as a key transport channel. The findings provide a deep understanding of the origins and long-distance trans-boundary transport of both 129 I and other volatile airborne radioactive pollutants to the STP.