The data of 17 air quality monitoring stations of Greater Cairo are used to perform a statistical analysis aiming to detect any heterogeneous surface effects of mineral dust on the distribution of reactive trace gases (SO₂ NO₂, and ozone) in. After a thorough quality check, the methodology consisted of i) selecting representative stations by agglomerative hierarchical clustering, ii) identifying dust events based on PM₁₀ measurements, remote sensing observations, and meteorology, and iii) applying the non-parametric Kruskal Wallis (KW) hypothesis test to compare (at the 95% confidence level) trace gas concentrations during dust and non-dust events. The representative stations display either a background-like or a bimodal variability with concentrations (even that of the secondary product NO₂) peaking at traffic rush hours but during dust storms all stations capture the signal of mineral dust advection. Eight wintertime and springtime dust cases are retained for the study. After the role of the confounding factors (i.e., ventilation index, relative humidity, and photolysis) has been carefully discussed and taken into account, the KW test shows that there is no significant reduction of the SO₂, NO₂ and ozone concentrations attributable to dust during 7 of the 8 events. The drop of the concentrations coinciding with the advection of dry dust-laden Saharan air masses is rather an effect of the dilution resulting from the combination of large wind speed and mixing layer height than of the heterogeneous uptake of these gases on the mineral dust surface.

_{利用大开罗地区17个空气质量监测站的数据进行统计分析，旨在检测矿物粉尘对反应性微量气体（SO 2} NO ₂和臭氧）分布的异质表面影响。检查，该方法包括 i) 通过凝聚层次聚类选择代表性站点，ii) 根据 PM _{10识别灰尘事件}测量、遥感观测和气象学，以及 iii) 应用非参数 Kruskal Wallis (KW) 假设检验来比较（在 95% 置信水平下）灰尘和非灰尘事件期间的痕量气体浓度。代表性站点显示出类背景或双峰变化，浓度（甚至是二次产品 NO ₂的浓度）在交通高峰时段达到峰值，但在沙尘暴期间，所有站点都捕获矿物粉尘平流信号。保留了八个冬季和春季的沙尘案例用于研究。_{经过仔细讨论和考虑混杂因素（即通风指数、相对湿度和光解）的作用后，KW测试表明SO 2}、NO没有明显减少。₂和臭氧浓度归因于 8 次事件中的 7 次期间的灰尘。与充满干燥尘埃的撒哈拉气团平流一致的浓度下降，更多的是由于大风速和混合层高度的组合而导致的稀释效应，而不是这些气体在矿物尘埃表面的不均匀吸收。