運用校正後微型感測器監測在空氣品質維護區的交通相關的空氣汙染

Abstract

近年來，全球興起劃設空氣品質維護區的浪潮，希望以減少交通相關的空氣汙染的方式來提升市區整體空氣品質。目前各國在評估空氣品質維護區內的空氣品質多直接使用標準測站測值進行全面評估，難以捕捉空氣汙染高解析度的空間分布變化。交通相關空氣污染 (TRAP) 會對道路使用者的健康產生不利影響，因此持續監測暴露的重要性已被強調。 其中以PM2.5與對敏感族群用路者(孩童、老人、其他敏感族群)的心血管、呼吸道疾病最為明顯。 本研究旨在探討使用校正後微型感測器評估空氣品質維護區內空氣污染對人體健康影響之可行性，並尋找影響交通相關的空氣汙染的關鍵因素(車流、天氣因子)。微型感測器因其低成本、易於操作以及能夠提供高解析度的時間、空間監測的特色而被作為周邊未設大型標準測站選點的替代方案。 本研究經美國環境保護署提出之感測器測試協定標準評估後，納入天氣因子建構適當微型感測器校正模型。接著使用校正好的微型感測器實地監測台北市空氣品質維護區內交通相關的空氣汙染污染物(PM2.5)濃度，並與周邊交通、交通車流因子進行關聯性分析。 將空氣品質維護區的空氣汙染污染物(PM2.5)濃度與全球空氣品質標準進行比較，我們的日平均PM2.5濃度在空氣品質指標分類中多數時間為良好。此外，影響每小時三台感測器的測值的主要因子為相對濕度、平均溫度與風向。交通車流因子的表現較不顯著。本研究可應用於評估空氣品質維護區內交通相關的空氣汙染污染之個人暴露及健康危害評估。

In recent years, the establishment of Low-Emission Zones (LEZs) globally has aimed to improve urban air quality by mitigating traffic-related air pollution (TRAP), which is known to adversely impact the health of road users. Currently, many countries use monitoring station measurements for comprehensive assessments of air quality within LEZs, which often fail to capture high-resolution spatial variations in TRAP. This study aims to explore the feasibility of using calibrated Low-Cost Sensors (LCS) to assess the health impacts of TRAP within LEZs and to identify key factors influencing TRAP distribution. LCS has been proposed as an alternative solution for areas without large monitoring stations due to their advantages of cost efficiency, compact sizes, ease of operation, and the ability to provide high-resolution monitoring spatially and temporally. This study aims to explore the feasibility of using calibrated Low-Cost Sensors (LCS) to assess the health impacts of air pollution within LEZs and to identify key factors influencing TRAP (traffic flow and meteorological factors). Low-cost sensors (LCS) have been proposed as an alternative solution for areas without large monitoring stations due to their advantages of cost efficiency, compact sizes, ease of operation, and the ability to provide high-resolution monitoring spatially and temporally. After evaluating the three LCSs according to the U.S. Environmental Protection Agency's sensor testing protocol and incorporating meteorological factors to construct an appropriate calibration model, the calibrated LCS was used to monitor TRAP (PM2.5) concentrations within the Taipei LEZ. The comparison of daily PM2.5 concentrations within the LEZ with global air quality standards shows satisfactory conditions. Furthermore, the main meteorological factors affecting the readings of the three sensors were relative humidity, average temperature, and wind direction, and traffic factors were total traffic flow and average speed for certain VDs. This research provides valuable insights for improving TRAP monitoring within LEZs and offers guidance for future studies at the intersection of TRAP exposure and the effectiveness of LEZ policy.