Guangxi Key Laboratory of Marine Environmental Change and Disaster in Beibu Gulf, Ocean College, Beibu Gulf University, Qinzhou 535011, China.
School of Fishery, Zhejiang Ocean University, Zhoushan 316022, China.
Environ Sci Technol. 2024 Sep 3;58(35):15702-15710. doi: 10.1021/acs.est.4c02159. Epub 2024 Aug 19.
While atmospheric microplastics are known to be transported over long distances, their residence times and transport processes lack clarity. This study utilized natural radionuclides Be, Pb, and Po to explore the transport of atmospheric microplastics in Tianjin, a coastal city in Northern China. Microplastic concentrations ranged from 0.03 to 0.13 particles m over the course of a year. The proportion of microplastic fragments in winter was significantly higher than that in other seasons, with median microplastic sizes in autumn and winter being larger than those in spring and summer. The atmospheric microplastic surface was rough, exhibiting irregular pores and multiple depressions and cracks. Microplastics experienced vertical mixing with the upper atmosphere in April and August and were influenced by rainfall in July. The residence time of atmospheric particles ranged from 9.47 to 22.85 days throughout the year, with an average of 14.41 days. The peak residence time of atmospheric particulates in November may be correlated with increased Po levels from coal consumption. Their prolonged atmospheric presence and rough surface allow microplastics to act as carriers for various chemical pollutants, underscoring the complexity and potential risks associated with their presence in the atmosphere.
虽然已知大气中的微塑料可以长距离传输，但它们的停留时间和传输过程仍不清楚。本研究利用天然放射性核素 Be、Pb 和 Po 来探索中国北方沿海城市天津大气中微塑料的传输。在一年的时间里，大气中微塑料的浓度范围为 0.03 到 0.13 个颗粒/立方米。冬季微塑料碎片的比例明显高于其他季节，秋季和冬季的大气中微塑料平均粒径大于春季和夏季。大气中的微塑料表面粗糙，呈现不规则的孔隙和多个凹陷和裂缝。微塑料在 4 月和 8 月与上层大气发生垂直混合，并受到 7 月降雨的影响。大气颗粒物的停留时间在全年范围内为 9.47 到 22.85 天，平均为 14.41 天。11 月大气颗粒物的停留时间峰值可能与煤炭消耗导致的 Po 水平升高有关。它们在大气中的长时间存在和粗糙表面使微塑料成为各种化学污染物的载体，这凸显了它们在大气中存在的复杂性和潜在风险。
