近日，广东工业大学环境健康与污染控制研究院、环境科学与工程学院安太成、李桂英教授团队在生活垃圾填埋场生物气溶胶小尺度区域扩散机理方面取得了最新进展，研究成果以《Abundance and cultivable bioaerosol transport from a municipal solid waste landfill area and its risks》为题发表在 “Environmental Pollution，2023，320，121038”（IF2021=9.988 CiteScore:12.7）期刊上。论文的第一作者为张婷博士后，通讯作者为李桂英教授。

生物气溶胶是重要的空气污染物，垃圾填埋场排放生物气溶胶随空气运动传播，导致可能的人群暴露，探明生物气溶胶区域大气扩散机理，有利于环境污染控制与职业工人/居民的健康风险管理。本研究针对典型城市固体废物垃圾填埋场（MSWLF）排放生物气溶胶，新建立了一种基于GIS-CFD拉格朗日法的风洞观测、现场监测验证的气溶胶区域大气扩散模型。风洞实验证实，静风条件下，人为源排放气溶胶（空气动力学直径：0.5−15 μm）近地面区域的水平扩散速度高于垂直扩散速度。研究发现，7种不同组成的生物气溶胶大气扩散特征（扩散距离、扩散速度、活菌浓度）明显不同。相比于大肠杆菌气溶胶的长距离扩散浓度，大肠杆菌气溶胶黏附空气中微米颗粒物的扩散浓度更高；大肠杆菌黏附生物质颗粒物的近距离（＜0.3 m）扩散浓度提高了14%，特别是在不利的风环境下，特征聚集形式生物气溶胶的扩散浓度不随着扩散距离的增加而降低。进一步，研究基于拉格朗日方法的气溶胶大气扩散模型，精细预测了静风条件下垃圾填埋场排放生物气溶胶在城区的扩散方向与>10 Km的扩散轨迹。随后，现场采集生物气溶胶的TEM图像验证了生物气溶胶4类组成形式，呈现了垃圾填埋场下风向的细颗粒物（PM_2.5, PM₁₀）浓度正比于可培养致病细菌、真菌（伤寒沙门氏菌、藤黄微球菌、红球菌、黑曲霉等）浓度的事实，提示了MSWLF周边高呼吸暴露风险区的存在。新取得的研究成果可以为城市区域生物气溶胶的污染防治和健康管理提供一种新机理。

论文链接：https://doi.org/10.1016/j.envpol.2023.121038

图文摘要：

英文摘要：

Municipal solid waste (MSW) landfills, constituting the third largest anthropogenic sources of bioaerosols, are suspected to be one of the major contributors to adverse health outcomes. A regional modeling of aerosol trajectories based on wind-tunnel observations and on-site monitoring was newly-developed to uncover the impacts of a typical MSW landfill on ambient bioaerosol pollution. Results showed that the horizontal diffusion velocity of bioaerosols reached 4.33 times higher than the vertical velocity under surface calm winds. On-site monitoring revealed that the concentrations of particulate matter (PM) with a diameter of 10 μm were 3.05 times higher than those of PM1.0 in the 2.8-km downwind residential regions near the MSW landfill. With the increase in PM concentration, higher-abundance microorganisms were detected. A number of cultivable bacterial species (Micrococcus endophyticus, Micrococcus flavus, Bacillus sporothermodurans, Salmonella enterica serovar typhi, Rhodococcus hoagie, Blastococcups) and fungal species (Aspergillus niger, Penicillium, Microascus cirrosus, Cochliobolus, Stemphylium vesicarium) were identified in these bioaerosols. Furthermore, distinguished by transmission electron microscopy, a longer-range transported microorganism (E. coli) clinging onto suspended PM was observed, signifying higher exposure risks. Human health risk assessments demonstrate that the residents and occupational workers in the vicinity of MSW landfill endured atmospheric diffusion-induced bioaerosol exposure risks due to open dumping activities in MSW landfill. This study clearly indicates bioaerosol pollution from landfills, and people particularly living nearby the MSW facilities, must decrease outdoor activities during dusty days.