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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. Image 1 • The bus units of three different routes were sampled during morning rush hours. • Fourteen volatile organic compounds were identified as persistent pollutants. • Correlation analysis indicates multiple emission sources for persistent VOCs. • Xylene concentrations represents the higher risk to the commuter's health. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the early detection of anthracnose and soft rot diseases in cold stored strawberry fruit by evaluating the CO 2 and volatile organic compounds (VOCs) released by the fungi Colletotrichum fragariae and Rhizopus stolonifer. Strawberries were stored at 5, 10 and 21 °C (control group) and the VOCs and CO 2 production of inoculated and non-inoculated strawberries were followed by gas chromatography. To evaluate and estimate the growth of both fungi, the CO 2 data were fitted to the Gompertz model. Data of the VOCs released at the end of the fungal growth were analyzed using principal components analysis (PCA) to discriminate between infected and non-infected strawberries. The results showed that fungal growth was affected by temperature and C. fragariae had a maximum growth after 14.6 h at 5 °C and R. stolonifer at 21 °C after 45.2 h. On the other hand, through VOCs released by C. fragariae and R. stolonifer and PCA, four groups were obtained: a) strawberry infected with C. fragariae , stored at 10 °C, b) strawberry infected with R. stolonifer , stored at 21 °C, c) control group kept at 10 °C and, d) strawberry infected with C. fragariae and control group (5 and 21 °C), and strawberry infected with R. stolonifer at 5 and 10 °C. In conclusion, CO 2 and VOCs released by C. fragariae and R. stolonifer on strawberries could infer the presence of anthracnose and soft rot during storage of the fruit at low temperature. [ABSTRACT FROM AUTHOR]