| Summary: | 碩士 === 元培醫事科技大學 === 環境工程衛生系碩士班 === 107 === This study investigated the monthly and seasonal concentration variations, sources and carcinogenic risk values of fine aerosols (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) on different floors of the residence in the Yunlin.
The sampling location is located on the balcony of the 2nd and 4th floors of the residence at the Linnei Township, Yunlin County. It is about 4.8 meters away from Taiwan Provincial Highway No. 3, the height of the second floor is about 5.4 meters, and the fourth floor is about 11.9 meters. The sampling period is from January 2017 to July 2018. The sampling equipment is a 37 mm quartz filter paper with a Personal Environmental Monitor. The sampling flow rate is set to 10 L/min and the sampling time is 24 hours. A total of 106 samples were analyzed by gas chromatography/mass spectrometer to analyze 22 PAHs on the PM2.5.
The experimental results show that the PM2.5 concentrations on the 2nd floor of residence durning four seasons are 7.47 – 56.62, 6.99 – 43.23, 3.76 – 71.47 and 20.89 – 56.88 μg/m3, respectively; the PAHs concentration ranges are 0.76 – 2.84, 0.76 – 1.85, 0.97 – 3.57 and 2.20 – 5.79 ng/m3, respectively; the total equivalent BaP toxic concentrations of PAHs are 0.20, 0.17, 0.23 and 0.37, respectively. The PM2.5 concentrations on the 4th floor of residence durning four seasons are 3.75 – 54.61, 6.23 – 45.93, 2.40 – 66.84 and 19.41 – 63.60 μg/m3, respectively; its total PAHs concentration range is 0.67 – 2.77, 0.68 – 1.28, 0.83 – 2.99 and 1.91 – 4.45 ng/m3; the total equivalent BaP toxic concentrations of PAHs are 0.18, 0.13, 0.23 and 0.35, respectively. The PM2.5 and total PAHs concentration from high to low is the winter > autumn > spring > summer. The results show that there are significant differences for the PM2.5 and total PAHs concentrations between the 2nd and 4th floors of the the residence. The PM2.5 and total PAHs concentration on the 2nd and 4th floors of the residence is higher in winter than in other seasons, which may be related to the mixed layer, wind direction and wind speed in the area. The ratio of the 4th to 2nd floors for PM2.5 and PAHs of the residence is 0.95 and 0.90, respectively. After the results were analyzed by statistics, there is no significant difference for the PM2.5 and total PAHs concentrations between the 2nd and 4th floors of the residence. The carcinogenic risk values of total PAHs on the 2nd and 4th floors of the residence are 2.57 × 10-5 and 2.36 × 10-5, respectively. By the characteristic ratios of BghiP/Bep and Cor/Bep analyzing, the source mainly contributed to the vehicle exhaust.
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