PEMANTAUAN KONSENTRASI GAS (CO2, NO2) DAN PARTIKULAT (PM2.5) PADA STRUKTUR HORIZONTAL DI KAWASAN DAYEUHKOLOT, CEKUNGAN UDARA BANDUNG RAYA

Salah satu sumber polusi lokal yang terjadi di Bandung Raya berasal dari kendaraan bermotor. Dari penelitian sebelumnya terindikasi bahwa konsentrasi organic carbon (OC) lebih tinggi dari elemental carbon (EC), konsentrasi OC primer lebih tinggi dari OC sekunder, dan konsentrasi char-EC lebih tinggi dari soot-EC. Penelitian tersebut menggunakan metode dry sampling dengan perangkat cascade impactor dan teridentifikasi bahwa OC, OC primer, dan char-EC berasal dari kendaraan bermotor khususnya mesin diesel, asap pabrik, dan debu jalan. Penelitian ini bertujuan untuk memantau dan menganalisis persebaran polusi lokal secara horizontal di daerah Dayeuhkolot, cekungan udara Bandung Raya. Pemantauan kualitas udara (CO2, NO2 , dan PM2.5 ) dengan menggunakan sepeda dilakukan pada tiga tipe lintasan: (1) jalur hijau, (2) lalu lintas rendah, dan (3) jalan raya. Ketiga lintasan memiliki karakteristik yang unik sesuai dengan estimasi sumber pencemar dan faktor lingkungan seperti pepohonan. Alat ukur yang digunakan berbasis low-cost sensors (CO2, NO2, dan PM2.5 ), serta dilengkapi dengan sensor temperatur (T), kelembapan relatif (RH), dan data logger. Pengukuran dilakukan selama 15 kali pada Februari-Maret 2019. Rata-rata pengamatan dilakukan setiap ~2 jam dengan kecepatan rata-rata sepeda ~10 km jam -1 . Hasil pengukuran menunjukkan bahwa alat dapat mendeteksi fluktuasi konsentrasi emisi gas/partikulat, yang dipengaruhi oleh konsentrasi polutan di udara sesaat yaitu dari kendaraan bermotor, pembakaran sampah, aktivitas pasar minggu, dan pengaruh hujan. Pada saat lampu merah di persimpangan jalan, tampak bahwa emisi langsung dari kendaraan bermotor dapat meningkatkan konsentrasi PM 2.5 dan NO2 menjadi 110 μg m-3 dan ~0,15 ppm pada selang waktu pengukuran ~10 menit. Faktor lainnya yang dapat meningkatkan nilai konsentrasi PM 2.5 sebesar ~163 μg m-3 dari kondisi udara ambien (77-86 μg m-3) adalah pembakaran sampah (~4 menit). Sedangkan kegiatan rutin di pasar minggu pagi dapat meningkatkan konsentrasi CO2 dan NO2 menjadi ~931 ppm dan ~0,13 ppm (~8 menit). Air hujan yang biasa terjadi pada sore hari dapat menurunkan konsentrasi gas dan PM 2.5 . Tingkat pembilasan partikulat (r) akibat hujan adalah ~30%

Urban vertical air pollution gradient and dynamics investigated with low-cost sensors and large-eddy simulations

A network of five low-cost air pollution sensor (LCS) nodes was deployed vertically on the exterior of the H. C. Ørsted Institute at the University of Copenhagen, Denmark, to investigate the transport of pollution from the road below. All LCS nodes measured PM2.5, NO2, and O3 at 1-min time resolution, and one of them also measured noise. Traffic was monitored with a webcam, where traffic type and levels were derived using a machine-learning algorithm. We investigated how well traffic-related air pollution, noise, and real-time traffic counts serve as proxies for one another. The correlations between NO2, noise, and traffic count exhibited relatively low values when considering all the data. However, these correlations significantly increased under southwesterly wind direction and low wind speed, reaching R2 = 0.40 for NO2 and noise, R2 = 0.51 for NO2 and traffic volume, and R2 = 0.70 for noise and traffic volume. These results indicate a common source, namely traffic, for all three parameters. The five LCS nodes spanning 25 m vertically had extremely low intervariability with minimum R2-values of 0.98 for PM2.5, 0.89 for NO2, and 0.97 for O3. The system could not detect a vertical gradient in pollution levels. Large-eddy simulation model runs using the PALM model system generally supported the lack of gradient observed in measured observations. Under slightly unstable stratification, concentration remained relatively constant with height for southwesterly and southerly winds. Conversely, winds from the north, west, and northwest showed an increase in concentration with height. For other wind directions, the concentration decreased with height by approximately 40 % to 50 %, which is not as strong as for neutral stratification, attributed to enhanced vertical mixing under unstable stratification. Based on the measurements and modeling, we conclude that the vertical concentration profile is very sensitive to stratification, and under these conditions, the concentration outside the window of a fifth-floor office is almost the same as for an office on the ground floor

Development and On-Field Testing of Low-Cost Portable System for Monitoring PM2.5 Concentrations

Recent developments in the field of low-cost sensors enable the design and implementation of compact, inexpensive and portable sensing units for air pollution monitoring with fine-detailed spatial and temporal resolution, in order to support applications of wider interest in the area of intelligent transportation systems (ITS). In this context, the present work advances the concept of developing a low-cost portable air pollution monitoring system (APMS) for measuring the concentrations of particulate matter (PM), in particular fine particles with a diameter of 2.5 μm or less (PM2.5). Specifically, this paper presents the on-field testing of the proposed low-cost APMS implementation using roadside measurements from a mobile laboratory equipped with a calibrated instrument as the basis of comparison and showcases its accuracy on characterizing the PM2.5 concentrations on 1 min resolution in an on-road trial. Moreover, it demonstrates the intended application of collecting fine-grained spatio-temporal PM2.5 profiles by mounting the developed APMS on an electric bike as a case study in the city of Mons, Belgium

Monitoramento de material particulado usando sensor ótico SDS011 e o bioindicador Tradescantia sp. clone 4430 em Curitiba

Orientador: Prof. Emílio Graciliano Ferreira Mercuri, D.Sc.Coorientadora: Profa. Dra. Viviane Fernandes de SouzaDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Ambiental. Defesa : Curitiba, 17/09/2021Inclui referências: p. 91-105Resumo: A concentração de gases e partículas presentes na atmosfera terrestre estão em constante mudança e podemos observar isso através de vários estudos feitos ao longo dos anos. A crescente industrialização nos centros urbanos e o aumento da frota veicular são um dos muitos fatores que impactam nessa mudança, através das emissões de gases e particulados da queima de seus combustíveis. Percebendo a importância de mensurar estes poluentes é que foram elaboradas legislações para determinar limites máximos de concentrações de determinados poluentes. Portanto, realizar o monitoramento e a quantificação destes se faz tão importante, principalmente para o meio ambiente e a saúde pública. Redes de monitoramento são essenciais para o cumprimento da legislação, porém, seu alto custo impossibilita a instalação em vários locais, por isso deve-se buscar alternativas mais acessíveis para monitorar a qualidade do ar. Sensores óticos e de baixo custo têm se mostrado como uma boa alternativa para este fim, devido a sua fácil operacionalização. Outra alternativa é biomonitoramento ambiental com o uso de bioindicadores, que apresentam sensibilidade às alterações do ambiente, fácil instalação e interpretação dos resultados. Aliar o monitoramento físico com o biológico, torna-se uma importante ferramenta para o acompanhamento da qualidade do ar, pois verifica-se se a legislação está sendo atendida e se a presença dos poluentes pode trazer algum malefício para o ecossistema. Desta forma, este trabalho usou o sensor ótico SDS011 para medir as concentrações de material particulado em Curitiba e Araucária e o bioindicador Tradescantia sp. clone 4430 através do bioensaio Trad-SHM, para verificar a mutagenicidade ambiental deste poluente. Os sensores e os vasos com as plantas foram distribuídos em oito pontos (sete em Curitiba e um em Araucária), e as análises ocorreram no período de janeiro de 2020 a fevereiro de 2021. O controle negativo foi realizado em um bairro de Curitiba, onde as plantas e o sensor ficaram em local isolado do ambiente externo com o uso de papel filtro. Os resultados de medições de material particulado para os pontos de monitoramento, atenderam em grande parte os limites especificados no CONAMA 491/2018, sendo que por 19 dias ficaram acima do limite para o material particulado MP100µg/m3 e 47 dias para o MP2.50µg/m3. O bioensaio Trad-SHM mostrou sensibilidade durante a exposição em campo, com frequências de mutação em pelo estaminal em todos os pontos de monitoramento. A média das correlações de Spearman (r) entre material particulado e frequência de mutação ficou em 0,45 ± 0,21 (correlação moderada). A continuidade de biomonitoramento se torna importante para o acompanhamento da presença de poluentes no ar, pois estes ainda são capazes de causar efeitos mutagênicos nos bioindicadores e o uso do sensor SDS011 se mostrou como uma boa alternativa para o monitoramento de material particulado.Abstract: The concentration of gases and particles present in the Earth's atmosphere is constantly changing and we can observe this through several studies carried out over the years. The growing industrialization in urban centers and the increase in the vehicle fleet are one of the many factors that impact this change, through the emissions of gases and particulates from the burning of their fuels. Realizing the importance of measuring these pollutants is that legislation was drawn up to determine maximum limits of concentrations of certain pollutants. Therefore, monitoring and quantifying these is so important, especially for the environment and public health. Monitoring networks are essential for complying with legislation, however, their high cost makes it impossible to install them in several places, so more accessible alternatives for monitoring air quality should be sought. Optical and low-cost sensors have proved to be a good alternative for this purpose, due to their easy operation. Another alternative is environmental biomonitoring with the use of bioindicators, which show sensitivity to changes in the environment, easy installation and interpretation of results. Combining physical and biological monitoring becomes an important tool for monitoring air quality, as it is verified whether the legislation is being complied with and whether the presence of pollutants can harm the ecosystem. Thus, this work used the optical sensor SDS011 to measure the concentrations of particulate matter in Curitiba and Araucária and the bioindicator Tradescantia sp. clone 4430 through the Trad-SHM bioassay to verify the environmental mutagenicity of this pollutant. The sensors and pots with the plants were distributed at eight points (seven in Curitiba and one in Araucaria), and the analyzes took place from January 2020 to February 2021. The negative control was carried out in a district of Curitiba, where the plants and the sensor were kept in a place isolated from the external environment using filter paper. The results of particulate material measurements for the monitoring points largely complied with the limits specified in CONAMA 491/2018, and for 19 days they were above the limit for particulate matter PM100µg/m3 and 47 days for PM2.50µg/m3. The Trad-SHM bioassay showed sensitivity during field exposure, with mutation frequencies in stem hair at all monitoring points. The mean of Spearman correlations (r) between particulate matter and mutation frequency was 0,45 ± 0,21 (moderate correlation). The continuity of biomonitoring becomes important for monitoring the presence of pollutants in the air, as they are still capable of causing mutagenic effects on bioindicators and the use of the SDS011 sensor proved to be a good alternative for monitoring particulate matter