Browsing by Author "Stabile, L."

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Open Access
Formation of cluster mode particles (1–3 nm) in preschools
(Elsevier BV, 2021-11-23) Torkmahalleh, M. A.; Turganova, K.; Zhigulina, Z.; Madiyarova, T.; Adotey, E. K.; Malekipirbazari, Milad; Buonanno, G.; Stabile, L.
This study is the first study that reports the cluster particle (1–3 nm) formation (CPF) in two modern preschools located in Nur-Sultan city of Kazakhstan from October 28 to November 27, 2019. The average particle number concentration and mode diameter values during major CPF events in Preschool I and Preschool II were found to be 1.90 × 10^6 (SD 6.43 × 106) particles/cm3 and 1.60 (SD 0.85) nm, and 1.11 × 109 (SD 5.46 × 109) particles/cm3 and 2.16 (SD 1.47) nm, respectively. The ultraviolet PM concentration reached as high as 7 μg/m3 in one of the measurement days. The estimated emission rate in Preschool I for CPF events was 9.57 × 109 (SD 1.92 × 109) particles/min. For Preschool II, the emission rate was 7.25 × 109 (SD 12.4 × 109) particles/min. We identified primary cluster particles (CPs) emitted directly from the sources such as candle burning, and secondary CPs formed as a result of the oxidation of indoor VOCs or smoking VOCs. The secondary CPs are likely to be SOA. Indoor VOCs were mainly emitted during cleaning activities as well as during painting and gluing. Indoor VOCs are the controlling factors in the CPF events. Changes in the training and cleaning programs may result in significant reductions in the exposure of the children to CPs.
Open Access
Global air quality and COVID-19 pandemic: do we breathe cleaner air?
(Taiwan Association for Aerosol Research,Taiwan Qijiao Yanjiu Xuehui, 2021-02-08) Torkmahalleh, M. A.; Akhmetvaliyeva, Z.; Omran, A. D.; Omran, F. D.; Kazemitabar, M.; Naseri, M.; Motahareh, N.; Hamed, S.; Malekipirbazari, Milad; Adotey, E. K.; Soudabeh, G.; Neda, E.; Sabanov, S.; Alastuey, A.; Andrade, M. F.; Buonanno, G.; Carbone, S.; Cárdenas-Fuentes, D. E.; Cassee, F. R; Dai, Q.; Henríquez, A.; Hopke, P. K.; Keronen, P.; Khwaja, H. A.; Kim, J.; Kulmala, M.; Kumar, P.; Kushta, J.; Kuula, J.; Massagué, J.; Mitchell, T.; Mooibroek, D.; Morawska, L.; Niemi, J. V.; Ngagine, S. H.; Norman, M.; Oyama, B.; Oyola, P.; Öztürk, F.; Petäjä, T.; Querol, X.; Rashidi, Y.; Reyes, F.; Ross-Jones, M.; Salthammer, T.; Savvides, C.; Stabile, L.; Sjöberg, K.; Söderlund, K.; Raman, R. S.; Timonen, H.; Umezawa, M.; Viana, M.; Xie, S.
The global spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has challenged most countries worldwide. It was quickly recognized that reduced activities (lockdowns) during the Coronavirus Disease of 2019 (COVID-19) pandemic produced major changes in air quality. Our objective was to assess the impacts of COVID-19 lockdowns on groundlevel PM2.5, NO2, and O3 concentrations on a global scale. We obtained data from 34 countries, 141 cities, and 458 air monitoring stations on 5 continents (few data from Africa). On a global average basis, a 34.0% reduction in NO2 concentration and a 15.0% reduction in PM2.5 were estimated during the strict lockdown period (until April 30, 2020). Global average O3 concentration increased by 86.0% during this same period. Individual country and continent-wise comparisons have been made between lockdown and business-as-usual periods. Universally, NO2 was the pollutant most affected by the COVID-19 pandemic. These effects were likely because its emissions were from sources that were typically restricted (i.e., surface traffic and non-essential industries) by the lockdowns and its short lifetime in the atmosphere. Our results indicate that lockdown measures and resulting reduced emissions reduced exposure to most harmful pollutants and could provide global-scale health benefits. However, the increased O3 may have substantially reduced those benefits and more detailed health assessments are required to accurately quantify the health gains. At the same, these restrictions were obtained at substantial economic costs and with other health issues (depression, suicide, spousal abuse, drug overdoses, etc.). Thus, any similar reductions in air pollution would need to be obtained without these extensive economic and other consequences produced by the imposed activity reductions.
Open Access
In Press, Corrected Proof: Formation of cluster mode particles (1–3 nm) in preschools
(Elsevier, 2021-11-23) Torkmahalleh, M. A.; Turganova, K.; Zhigulina, Z.; Madiyarova, T.; Adotey, E. K.; Malekipirbazari, Milad; Milad, G.; Stabile, L.
This study is the first study that reports the cluster particle (1–3 nm) formation (CPF) in two modern preschools located in Nur-Sultan city of Kazakhstan from October 28 to November 27, 2019. The average particle number concentration and mode diameter values during major CPF events in Preschool I and Preschool II were found to be 1.90 × 106 (SD 6.43 × 106) particles/cm3 and 1.60 (SD 0.85) nm, and 1.11 × 109 (SD 5.46 × 109) particles/cm3 and 2.16 (SD 1.47) nm, respectively. The ultraviolet PM concentration reached as high as 7 μg/m3 in one of the measurement days. The estimated emission rate in Preschool I for CPF events was 9.57 × 109 (SD 1.92 × 109) particles/min. For Preschool II, the emission rate was 7.25 × 109 (SD 12.4 × 109) particles/min. We identified primary cluster particles (CPs) emitted directly from the sources such as candle burning, and secondary CPs formed as a result of the oxidation of indoor VOCs or smoking VOCs. The secondary CPs are likely to be SOA. Indoor VOCs were mainly emitted during cleaning activities as well as during painting and gluing. Indoor VOCs are the controlling factors in the CPF events. Changes in the training and cleaning programs may result in significant reductions in the exposure of the children to CPs.