Reducing the Influence of Environmental Factors on Performance of a Diffusion-Based Personal Exposure Kit

Sensor technology has enabled the development of portable low-cost monitoring kits that might supplement many applications in conventional monitoring stations. Despite the sensitivity of electrochemical gas sensors to environmental change, they are increasingly important in monitoring polluted microenvironments. The performance of a compact diffusion-based Personal Exposure Kit (PEK) was assessed for real-time gaseous pollutant measurement (CO, O3, and NO2) under typical environmental conditions encountered in the subtropical city of Hong Kong. A dynamic baseline tracking method and a range of calibration protocols to address system performance were explored under practical scenarios to assess the performance of the PEK in reducing the impact of rapid changes in the ambient environment in personal exposure assessment applications. The results show that the accuracy and stability of the ppb level gas measurement is enhanced even in heterogeneous environments, thus avoiding the need for data post-processing with mathematical algorithms, such as multi-linear regression. This establishes the potential for use in personal exposure monitoring, which has been difficult in the past, and for reporting more accurate and reliable data in real-time to support personal exposure assessment and portable air quality monitoring applications.

PERSONAL EXPOSURE ASSESSMENT OF FINE PARTICULATE MATTER FOR COMMUTERS IN HANOI

Các nghiên cứu dịch tễ học chứng minh rằng, người tham gia giao thông phơi nhiễm với bụi mịn có thể gây những ảnh hưởng xấu tới sức khỏe và gây ra bệnh tật. Các nghiên cứu về phơi nhiễm cá nhân đối với những người tham gia giao thông chưa được thực hiện một cách đầy đủ và tương đối hạn chế ở Việt Nam. Nghiên cứu này nhằm mục đích đánh giá phơi nhiễm bởi PM2.5 đối với người đi xe máy và xe đạp trên một số tuyến đường ở Hà Nội. Phơi nhiễm bụi cá nhân được lấy từ thiết bị đo bụi cảm biến Airbeam. Kết quả ban đầu cho thấy rằng, nồng độ phơi nhiễm của PM2.5 đối với người đi xe đạp (105 µg/m3) cao hơn người đi xe máy (95 µg/m3) và nồng độ PM2.5 trong không khí xung quanh (34 µg/m3). Các yếu tố ảnh hưởng cũng được đánh giá trong nghiên cứu này. Nồng độ phơi nhiễm PM2.5 được phát hiện cao nhất vào buổi sáng, và có xu thế giảm dần với buổi chiều và trưa đối với cả hai phương tiện giao thông. Nồng độ PM2.5 phơi nhiễm dao động lớn trong giờ cao điểm. Người đi xe đạp có nguy cơ rủi ro cao hơn người đi xe máy do liều lượng hít thở bụi mịn lớn. Nghiên cứu đưa ra cảnh báo ban đầu về nguy cơ tác động sức khỏe đối với người tham gia giao thông cho những nhà quản lý đưa ra các biện pháp can thiệp kịp thời.

Academically Produced Air Pollution Sensors for Personal Exposure Assessment: The Canarin Project

The World Health Organization has estimated that air pollution is a major threat to health, causing approximately nine million premature deaths every year. Each individual has, over their lifetime, a unique exposure to air pollution through their habits, working and living conditions. Medical research requires dedicated tools to assess and understand individual exposure to air pollution in view of investigating its health effects. This paper presents portable sensors produced by the Canarin Project that provides accessible, real time personal exposure data to particulate matter. Our primary results demonstrate the use of portable sensors for the assessment of personal exposure to the different micro-environments attended by individuals, and for inspecting the short-term effects of air pollution through the example of sleep apnea. These findings underscore the necessity of obtaining contextual data in determining environmental exposure and give perspectives for the future of air pollution sensors dedicated to medical research.

Personal Exposure Assessment to Wi-Fi Radiofrequency Electromagnetic Fields in Mexican Microenvironments

In recent years, personal exposure to Radiofrequency Electromagnetic Fields (RF-EMF) has substantially increased, and most studies about RF-EMF with volunteers have been developed in Europe. To the best of our knowledge, this is the first study carried out in Mexico with personal exposimeters. The main objective was to measure personal exposure to RF-EMF from Wireless Fidelity or wireless Internet connection (Wi-Fi) frequency bands in Tamazunchale, San Luis Potosi, Mexico, to compare results with maximum levels permitted by international recommendations and to find if there are differences in the microenvironments subject to measurements. The study was conducted with 63 volunteers in different microenvironments: home, workplace, outside, schools, travel, and shopping. The mean minimum values registered were 146.5 μW/m2 in travel from the Wi-Fi 2G band and 116.8 μW/m2 at home from the Wi-Fi 5G band, and the maximum values registered were 499.7 μW/m2 and 264.9 μW/m2 at the workplace for the Wi-Fi 2G band and the Wi-Fi 5G band, respectively. In addition, by time period and type of day, minimum values were registered at nighttime, these values being 129.4 μW/m2 and 93.9 μW/m2, and maximum values were registered in the daytime, these values being 303.1 μW/m2 and 168.3 μW/m2 for the Wi-Fi 2G and Wi-Fi 5G bands, respectively. In no case, values exceeded limits established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Of the study participants (n = 63), a subgroup (n = 35) answered a survey on risk perception. According to these results, the Tamazunchale (Mexico) population is worried about this situation in comparison with several European cities; however, the risk perception changes when they are informed about the results for the study.

DYNAMIC ASSESSMENT OF PERSONAL EXPOSURE TO AIR POLLUTION FOR EVERYONE: A SMARTPHONE-BASED APPROACH

In Epidemiology, exposure assessment is the process of measuring or estimating the intensity of human exposures to an environmental agent such as air pollution. Healthcare agencies typically take into consideration yearly averaged pollution values and apply them to all citizens, in risk models. However distinct parts of cities can have significantly different levels of pollution and individual habits can influence exposure, too. Consequently, in epidemiology and public health, there is an increasing interest for personal exposure assessment, i.e. the capability of measuring the exposure of individuals. Within the EU H2020 PULSE project, an innovative mechanism for the individual and dynamic assessment of exposure to air pollution has been implemented. The present paper illustrates its technological and scientific components. The system has already been deployed to several pilot cities of the project and Pavia, Italy, has been the first one. In that city several hundreds of tracks have already been acquired and processed. Therefore, the paper thoroughly illustrates the assessment procedure with examples.

Commuters’ Personal Exposure Assessment and Evaluation of Inhaled Dose to Different Atmospheric Pollutants

Several studies evaluating exposure to pollutants in microenvironments (MEs) are available in the scientific literature, but studies that evaluate the inhaled doses of pollutants are few in number. Therefore, this study aimed to evaluate the exposure of commuters to different pollutants (i.e., nitrogen dioxide [NO2] and fractionated particulate matter [PM], including ultrafine particles [UFPs]) using miniaturized and portable real-time monitoring instruments in selected MEs; the inhaled doses of these pollutants were estimated for each of these MEs. Measurements were performed along a typical commute, considering different traffic and nontraffic MEs. Experimental data were collected over four working weeks in two different seasons (winter and summer). Different portable and miniaturized instruments were used to evaluate PM and NO2 exposure. Furthermore, physiological parameters were evaluated using a heart rate monitor. The principal results show that higher exposure levels were measured in Underground (for all PM fractions and NO2) and in Car (UFP), while lower levels were measured in Car (PM and NO2) and in Train (UFP). In contrast, higher values of the inhaled cumulative dose were estimated in environments defined as Other, followed by Walking (ht), while lower values were observed in Walking (lt) and in Car.