Commercial cooking is an important source of PM2.5, which adversely affects air quality, posing threats to human health. However, few studies have examined the effects of commercial cooking on outdoor air quality. We aimed to analyze characteristics of outdoor PM2.5 and ions from commercial cooking during cooking and non-cooking times in a popular restaurant area at Nankai University. The acidity and alkalinity of atmospheric PM2.5 based on the equivalent values of anions and cations and the formed compounds based on the ion concentrations and correlations between them were determined. The results showed that the mean PM2.5 concentration at the snack street during cooking times was 120.39 ± 58.52 μg/m3, approximately 1.4 times higher than at the comparison point. The total concentration of water-soluble inorganic ions accounted for approximately half of the PM2.5 emissions at both sampling points. High concentrations of Na+, NO3−, and SO42− were found at both sampling points. We found that NH4NO3, CaSO4, and CaCl2 formed at the snack street, whereas Ca(NO3)2, NH4NO3, and (NH4)2SO4 formed at the comparison point. Based on our analysis of the acid-base balance slopes, the atmospheric PM2.5 was alkaline. These results elucidate the characteristics of PM2.5-bound water-soluble inorganic ions formed during cooking.

中文翻译：

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烹饪过程中产生的 PM2.5 结合水溶性无机离子的特性


商业烹饪是 PM2.5 的重要来源，对空气质量产生不利影响，对人类健康构成威胁。然而，很少有研究检查商业烹饪对室外空气质量的影响。我们旨在分析南开大学一个受欢迎的餐厅区在烹饪和非烹饪时间商业烹饪产生的室外 PM2.5 和离子的特性。根据阴离子和阳离子的当量值测定大气 PM2.5 的酸碱度，根据离子浓度和它们之间的相关性测定形成的化合物。结果表明，小吃街在烹饪时间内的平均 PM2.5 浓度为 120.39 ± 58.52 μg/m3，约为对照组的 1.4 倍。在两个采样点，水溶性无机离子的总浓度约占 PM2.5 排放量的一半。在两个采样点均发现高浓度的 Na+、NO3− 和 SO42−。我们发现 NH4NO3 、 CaSO4 和 CaCl2 形成于小吃街，而 Ca（NO3）2 、 NH4NO3 和 （NH4）2SO4 形成于比较点。根据我们对酸碱平衡斜率的分析，大气 PM2.5 是碱性的。这些结果阐明了烹饪过程中形成的 PM2.5 结合水溶性无机离子的特性。