The present work intends to analyze the pollution level at the indoor environments of the public transport units of León Guanajuato, Mexico during winter season. An identification and quantification of persistent organic pollutants were carried out within three of the principal bus lines of the city in order to determine their possible origin, the differences in the levels of contamination between routes, and the potential risk to the health of the users, these analyses were carried out with different statistical techniques (ANOVA, PCA, and correlation network maps). Fourteen different organic compounds were identified as persistent pollutants. Although toluene and hexane were the compounds that were detected at the highest concentrations (average of 86.52 ± 56.1 μg m−3 and 183.33 ± 10.7 μg m−3, respectively), the correlation analysis showed that xylene, styrene, and ethylbenzene were the compounds that were mostly related to the other compounds identified as persistent. Otherwise, the statistical analysis of the concentration of these pollutants allowed to establish the fuel combustion vapors as the main source of these compounds. In the same way, the potential exposition health risk to the users were calculated in accordance to the Environmental Protection Agency of United States on those commuters grouped as students and workers. This analysis shown that the xylenes are the most representative organic pollutant in this particulate indoor spaces, and is the one with potential to generate a greater risk to the health of the bus-users, this without demising the potential danger of other pollutants.

中文翻译：

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冬季公共交通工具内持久性室内挥发性有机化合物的评估


本研究旨在分析墨西哥莱昂瓜纳华托州公共交通单位冬季室内环境的污染水平。在该市的三条主要公交线路内对持久性有机污染物进行了鉴定和量化，以确定其可能的来源、路线之间污染水平的差异以及对用户健康的潜在风险，这些分析使用不同的统计技术进行（方差分析、 PCA 和相关网络图）。14 种不同的有机化合物被鉴定为持久性污染物。尽管甲苯和己烷是检测到最高浓度的化合物（平均值分别为 86.52 ± 56.1 μg m-3 和 183.33 ± 10.7 μg m-3），但相关性分析表明，二甲苯、苯乙烯和乙苯是与其他鉴定为持久性化合物最相关的化合物。否则，对这些污染物浓度的统计分析可以确定燃料燃烧蒸气是这些化合物的主要来源。同样，根据美国环境保护署对学生和工人等通勤者计算对用户的潜在世博健康风险。该分析表明，二甲苯是这种颗粒室内空间中最具代表性的有机污染物，并且有可能对公交车使用者的健康产生更大的风险，而不会消除其他污染物的潜在危险。