photochemical oxidant
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2021 ◽  
Vol 36 (4) ◽  
pp. e2021027
Author(s):  
Tasuku Okui

Although it has been known that the prevalence of asthma tends to be higher among children in the metropolitan areas of Japan, trends of the prevalence with respect to the regional urbanization level has not been investigated in recent years. We investigated trends in the prevalence of asthma among children and air pollutant concentrations by regional urbanization levels using data from the School Health Statistics Survey in Japan from 2006 to 2019. We calculated the age-standardized prevalence of asthma for each year, gender, regional urbanization level, and annual percent change (APC). In addition, the slope index of inequality (SII) and relative index of inequality (RII) were calculated for evaluating disparity in age-standardized asthma prevalence depending on regional urbanization levels. Moreover, we calculated the mean of the annual average values by regional urbanization levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), suspended particulate matter (SPM), carbon monoxide (CO), and photochemical oxidant (Ox) from 2006 to 2018. We found that the age-standardized prevalence significantly decreased in the periods in the metropolis for males and females, and the degree of the decrease was largest in the metropolis. Conversely, the age-standardized prevalence increased in towns and villages, and the APC was greater than zero. In addition, both the SII and RII showed significant decreasing trends in the study period, and the regional disparity shrank over the years. Moreover, concentrations of the air pollutants were highest in the metropolis throughout the years except for Ox, whereas the difference in the concentrations of NO2, SPM, and CO decreased between the metropolis and the other areas over the years. In conclusion, disparity in asthma prevalence depending on regional urbanization level decreased from 2006 to 2019, and there is a possibility that regional difference in trend of the air pollutants is related to the result.


2021 ◽  
Vol 13 (24) ◽  
pp. 13515
Author(s):  
Lahiba Imtiaz ◽  
Sardar Kashif-ur-Rehman ◽  
Wesam Salah Alaloul ◽  
Kashif Nazir ◽  
Muhammad Faisal Javed ◽  
...  

This study presents a life cycle impact assessment of OPC concrete, recycled aggregate concrete, geopolymer concrete, and recycled aggregate-based geopolymer concrete by using the mid-point approach of the CML 2001 impact-assessment method. The life cycle impact assessment was carried out using OpenLCA software with nine different impact categories, such as global warming potential, acidification potential, eutrophication potential, ozone depletion potential, photochemical oxidant formation, human toxicity, marine aquatic ecotoxicity, and freshwater and terrestrial aquatic ecotoxicity potential. Subsequently, a contribution analysis was conducted for all nine impact categories. The analysis showed that using geopolymer concrete in place of OPC concrete can reduce global warming potential by up to 53.7%. Further, the use of geopolymer concrete represents the reduction of acidification potential and photochemical oxidant formation in the impact categories, along with climate change. However, the potential impacts of marine aquatic ecotoxicity, freshwater aquatic ecotoxicity, human toxicity, eutrophication potential, ozone depletion potential, and terrestrial aquatic ecotoxicity potential were increased using geopolymer concrete. The increase in these impacts was due to the presence of alkaline activators such as sodium hydroxide and sodium silicate. The use of recycled aggregates in both OPC concrete and geopolymer concrete reduces all the environmental impacts.


Author(s):  
Witold-Roger Poganietz ◽  
Jasmin Friedrich ◽  
Helmut Lehn

AbstractWastewater systems in developed cities contribute significantly to public health. The related systems are energy and resource intensive and do not recover nutrients in an efficient and effective way. Separating wastewater to greywater and blackwater at the source and exploiting organic municipal solid waste as an additional feed to an adjunct biogas plant could support efforts to make use of the potentials to reduce the environmental impacts, to increase the energy efficiency of winning nutrients, and to implement an additional, locally available energy source. However, the implementation of such systems is seen as expensive.The overarching aim of the paper is to analyze the eco-efficiency of transforming the current separately organized wastewater-energy-waste systems to an integrated one. The study differs between three system alternatives. The least invasive system change assumes a separation of wastewater at the source without a complete overhaul of the current system; the most elaborated one takes the current wastewater system fully out of operation. The reference for the current system is the existing system of a German medium-sized urban neighborhood. The analysis considers the eco-efficiency of two resource-related (fossil and metal depletion) and three emissions-related (climate change, photochemical oxidant formation and terrestrial acidification) impacts.Under the conditions of the settlement investigated, a transformation to the system alternatives will generate in all cases a weak eco-efficiency, i.e. the higher costs of implementing a new system counteracts with the noteworthy environmental improvement. Of the three options, the most elaborated one sees the best performance.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2939
Author(s):  
Tahereh Soleymani Angili ◽  
Katarzyna Grzesik ◽  
Anne Rödl ◽  
Martin Kaltschmitt

So far, a lot of efforts have been put in life cycle assessments (LCA) of bioethanol production. There are many works that have assessed bioethanol production in different points of view to illustrate the environmental impacts. This study reviewed former LCA studies on bioethanol produced from various biomass resources by considering the effect of methodological components, technical pathways and feedstock provision on the result of LCA studies. The review evaluated 48 papers published 2002–2021 with a focus on studies that included a complete set of environmental impact categories. However, due to lack of harmony among studies, comparing the LCA results was challenging but the review indicated that the final results of studies are influenced by LCA methodological components, such as system boundary, functional unit, etc. Around 80% of the reviewed papers show the reduction in global warming potential, while contrary results have been found about increasing acidification, eutrophication and photochemical oxidant formation impact categories because of the feedstock provision. Regarding technical aspects, results from the review revealed that most of the studies considered the pre-treatment as a crucial step in bioconversion processes. Despite several LCA studies of bioethanol production, there is still low attention given to uncertainty analysis in the publications.


Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 446
Author(s):  
Akinori Fukunaga ◽  
Takaharu Sato ◽  
Kazuki Fujita ◽  
Daisuke Yamada ◽  
Shinya Ishida ◽  
...  

To clarify the relationship between changes in photochemical oxidants’ (Ox) concentrations and their precursors in Kawasaki, a series of analyses were conducted using data on Ox, their precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), and meteorology that had been monitored throughout the city of Kawasaki for 30 years from 1990 to 2019. The trend in air temperature was upward, wind speed was downward, and solar radiation was upward, indicating an increasing trend in meteorological factors in which Ox concentrations tend to be higher. Between 1990 and 2013, the annual average Ox increased throughout Kawasaki and remained flat after that. The three-year moving average of the daily peak increased until 2015, and after that, it exhibited a slight decline. The amount of generated Ox is another important indicator. To evaluate this, a new indicator, the daytime production of photochemical oxidant (DPOx), was proposed. DPOx is defined by daytime averaged Ox concentrations less the previous day’s nighttime averaged Ox concentrations. The trend in DPOx from April to October has been decreasing since around 2006, and it was found that this indicator reflects the impact of reducing emissions of NOx and VOCs in Kawasaki.


Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 335
Author(s):  
Yuki Okazaki ◽  
Lisa Ito ◽  
Akihiro Tokai

Photochemical oxidant concentration increases with the decrease in nitrogen oxide (NOx) concentration in volatile organic compound (VOC)-sensitive areas with several automobiles and factories. We aimed to quantify the changes in health risks from ozone (O3) and nitrogen dioxide (NO2) using disability-adjusted life years (DALY) in Osaka City, which is one of the major cities in Japan. ADMER-PRO version 1.0, an atmospheric model for secondary products, was used to estimate the concentration distribution of NO2, VOC, and O3 using the year-on-year change of traffic during the declaration of the state of emergency in response to the coronavirus disease 2019 (7 April to 21 May 2020). NO2 concentration decreased by an average of 0.962 ppb in 88.9% of the grids in Osaka City, whereas O3 concentration increased by an average of 1.00 ppb in all the grids with a 26–28% reduction of traffic volume due to the pandemic. We also found three intensities for the VOC-sensitive condition depending on the different regional emission characteristics, with the DALYs of health risks from the decrease in NO2 exceeding those from the increase in O3, reaching 811.4 and 55.90 total DALYs in the city, respectively.


2019 ◽  
Vol 57 (5) ◽  
pp. 606
Author(s):  
Khang Sy Dinh ◽  
Hung Phuoc Duong ◽  
Tuấn Đình Phan

Biodiesel that is produced from renewable resources has been rising as a promising candidate to replace conventional energy. Vietnam, with a large amount of land used in agriculture or forestry, has advantaged conditions to produce and develop renewable energy from biomass resources. However, developing biodiesel from agricultural product may affect food security significantly. Therefore, Jatropha that is inedible and waste cooking oil (WCO) could be suitable to biodiesel production. One of the most important aims of using biodiesel to replace fossil diesel is to reduce environmental impacts, particularly impact on Climate Change. It is necessary to analyze the environmental performance of biodiesel through the entire life cycle. In this paper, life cycle assessment of biodiesel production and use was applied to measure the environmental performance of biodiesel produced from jatropha oil and WCO under Vietnam conditions. Some main emissions, such as CO2, NOx, PM, CH4, VOC and land use, were computed through a cradle-to-grave analysis. The result shows that when using Jatropha biodiesel to replace diesel, global warming potential (GWP) and photochemical oxidant formation potential (POFP) could be improved, but some other impacts, such as acidification potential (AP) and eutrophication potential (EP), could tend to increase. The environmental impacts of WCO biodiesel are all reduced in comparison with fossil diesel.


Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3194 ◽  
Author(s):  
Lenka Laiblová ◽  
Jan Pešta ◽  
Anuj Kumar ◽  
Petr Hájek ◽  
Ctislav Fiala ◽  
...  

Pitch-faced concrete is becoming a very popular element of modern architecture in the 21st century. In particular, the demand for concrete facades is increasing globally. On the other hand, climate change, environmental degradation, and limited resources are motivations for sustainable building materials. The construction industry is one the highest emitters of CO2 and other greenhouse gases, in which concrete plays a major role. Thus, reduction in the volume of concrete consumption is essential to control greenhouse gases. One approach to this problem is to use textile reinforced concrete (TRC). The main aim of the present study was to compare the subtle TRC facade made of three different types of technical textile rovings (glass, carbon, and basalt) with ordinary facades reinforced by steel reinforcement (ORC). The goal was to compare the basic environmental impact potential according to product category rules (PCR) for concrete structures. The functional unit was defined as an experimental facade with an area of 60 m2 and a 100-year lifespan. Inventory data were elaborated for concrete, steel, and textile fiber production; the building site; service life; demolition; and final disposal. The main life cycle assessment (LCA) parameters were global warming potential (GWP), ozone depletion (ODP), acidification (AP), eutrophication (EP), abiotic depletion (ADP), and photochemical oxidant creation (POCP). All the data used in the work were related to Czech Republic. Textile reinforced concrete facades appeared to be more environmentally friendly in four of six impact categories by an average of 30%. The results of the present study revealed that, in comparison to ORC, TRC has a lower environmental impact for the given conditions and thus good potential for use in sustainable construction.


Atmosphere ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 505 ◽  
Author(s):  
Li Luo ◽  
Yong-Yun Zhang ◽  
Hua-Yun Xiao ◽  
Hong-Wei Xiao ◽  
Neng-Jian Zheng ◽  
...  

Chlorine is an important atmospheric photochemical oxidant, but few studies have focused on atmospheric chlorine. In this study, PM2.5 samples were collected from urban and rural sites across China in January 2018, and concentrations of Cl− and other water-soluble ions in PM2.5 were analyzed. The size-segregated aerosol Cl− data measured across Chinese cities by other studies were compiled for comparison. The observed data demonstrated that the Cl− concentrations of PM2.5 in northern cities (5.0 ± 3.7 µg/m3) were higher than those in central (1.9 ± 1.2 µg/m3) and southern cities (0.84 ± 0.54 µg/m3), suggesting substantial chlorine emissions in northern cities during winter. The concentrations of Cl− in aerosol were significantly higher in urban regions (0.11–26.7 µg/m3) compared to than in rural regions (0.03–0.61 µg/m3) across China during winter, implying strong anthropogenic chlorine emission in cities. Based on the mole ratios of Cl−/Na+, Cl−/K+ and Cl−/ SO 4 2 − and the PMF model, Cl− in northern and central cities was mainly sourced from the coal combustion and biomass burning, but in southern cities, Cl− in PM2.5 was mainly affected by the equilibrium between gas-phase HCl and particulate Cl−. The size-segregated statistical data demonstrated that particulate Cl− had a bimodal pattern, and more Cl− was distributed in the fine model than that in the coarse mode in winter, with the opposite pattern was observed in summer. This may be attributed to both sources of atmospheric Cl− and Cl− involved in chemical processes. This study reports the concentrations of aerosol Cl− on a national scale, and provides important information for modeling the global atmospheric reactive chlorine distribution and the effects of chlorine on atmospheric photochemistry.


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