Influence of fossil-fuel power plant emissions on the surface fine particulate matter in the Seoul Capital Area, South Korea

Ineffective implementation of emergency reduction measures against high concentrations of particulate matter in Seoul, Republic of Korea

Since December 30, 2017, the Seoul Metropolitan Government, Republic of Korea, has been implementing emergency reduction measures (ERMs) restricting the operation of industrial sites, thermal power plants, and vehicles when air quality is expected to deteriorate. ERMs are implemented when the present observed concentration of particulate matter (PM) of aerodynamic diameter less than 2.5 μm (PM2.5) and/or the predicted values for the following day exceed a threshold value. In this study, the effectiveness of ERMs was evaluated for 33 days with and 6 days without ERM implementation but where the PM2.5 concentration exceeded the threshold value, until March 15, 2021. Of the 33 days of ERM implementation, on 7 days it was executed despite the thresholds not being met. The ERM on these days might have been properly executed because the pre-notice and implementation of ERM might have reduced the local emissions of air pollutants. Our major findings are that even on days of ERM implementation, there were marginal reductions in vehicle traffic, thermal power generation, and industrial emissions. Second, the concentrations of PM2.5 and related air pollutants in Seoul were almost unchanged for most ERM implementation episodes. Third, most of the 39 (= 33 + 6) days when the air quality worsened were caused by the transboundary transport of air pollutants from China. In conclusion, it was revealed that the currently executed ERM law is insufficient for effectively reducing PM2.5. To achieve the required reductions, it is necessary to undertake stricter policies in Seoul and its neighboring regions.

Health effects of PM2.5 constituents and source contributions in major metropolitan cities, South Korea

Ambient PM_2.5 is one of the major risk factors for human health, and is not fully explained solely by mass concentration. We examined the short-term associations of cause-specific mortality (i.e., all-cause, cardiovascular, and respiratory mortality) with the 15 chemical constituents and sources of PM_2.5 in four metropolitan cities of South Korea during 2014-2018. We found transition metals consistently showed significant associations with all-cause mortality, while the effects of other constituents varied across the cities and for cause of death. Carbonaceous components strongly affected the all-cause, cardiovascular, and respiratory mortality in Daejeon. Secondary inorganic aerosols, SO₄^2- and NH₄⁺, showed significant associations with respiratory mortality in Gwangju. We also found the sources from which species closely linked to mortality generally increased the relative mortality risks. Heavy metal markers from soil or industrial sources were significantly associated with mortality in all cities. However, several sources influenced mortality despite their marker species not being significantly associated with it. Secondary nitrate and secondary sulfate sources were linked to mortality in DJ. This could be attributed to the deep inland location, which might have facilitated formation of secondary inorganic aerosols. In addition, primary sources including mobile and coal combustion seemed to have acute impacts on respiratory mortality in Gwangju. Our findings suggest the necessity of positive matrix factorization (PMF)-based approaches for evaluating health effects of PM_2.5 while considering the spatial heterogeneity in the compositions and source contributions of PM_2.5.

Effects and Mechanism of Particulate Matter on Tendon Healing Based on Integrated Analysis of DNA Methylation and RNA Sequencing Data in a Rat Model

Exposure to particulate matter (PM) has been linked with the severity of various diseases. To date, there is no study on the relationship between PM exposure and tendon healing. Open Achilles tenotomy of 20 rats was performed. The animals were divided into two groups according to exposure to PM: a PM group and a non-PM group. After 6 weeks of PM exposure, the harvest and investigations of lungs, blood samples, and Achilles tendons were performed. Compared to the non-PM group, the white blood cell count and tumor necrosis factor-alpha expression in the PM group were significantly higher. The Achilles tendons in PM group showed significantly increased inflammatory outcomes. A TEM analysis showed reduced collagen fibrils in the PM group. A biomechanical analysis demonstrated that the load to failure value was lower in the PM group. An upregulation of the gene encoding cyclic AMP response element-binding protein (CREB) was detected in the PM group by an integrated analysis of DNA methylation and RNA sequencing data, as confirmed via a Western blot analysis showing significantly elevated levels of phosphorylated CREB. In summary, PM exposure caused a deleterious effect on tendon healing. The molecular data indicate that the action mechanism of PM may be associated with upregulated CREB signaling.

Does new-type urbanization help reduce haze pollution damage? Evidence from China's county-level panel data

Urban transformation is the key to sustainable urban development. China is currently undergoing massive urban transformation, that is, new-type urbanization. This study explored the relationship between new-type urbanization construction and haze pollution by constructing a time-varying DID model based on 2013-2018 district and county data. Our empirical results show that new-type urbanization can significantly improve haze pollution. We also examined the heterogeneous differences in new-type urbanization's effects on haze pollution. First, we find that new urbanization construction has no significant effect on haze pollution in cities rich in natural resources. Second, its effect on haze pollution was most pronounced in the eastern region, which had the highest urbanization rate. This study also explored the moderating effect of new urbanization and haze pollution from the urban governance perspective. The results show that the government's fiscal spending capacity is significant for new-type urbanization's ability to improve haze pollution. In addition, in the pilot year, the turnover of regional officials enhanced new-type urbanization construction to improve haze pollution. We also find that districts and counties implementing pilot new-type urbanization are conducive to reducing haze pollution in surrounding areas in the same city not implementing new-type urbanization; however, they exacerbate haze pollution in other provincial areas that have not implemented new-type urbanization. Finally, we propose relevant policy recommendations based on the empirical results.

Application of a health index using PM2.5 concentration reductions for evaluating cross-administrative region air quality policies

The primary goal of air quality policies is to reduce the impact of air pollution on human health, in particular, it is very important in the attainment-closing geographic areas with densely populated like Taiwan. Air quality policies in general only consider the reduction of emission as well as concentration, in order to highlight the effects of air pollution reduction responded on human health, a health index using PM_2.5 concentration reductions (HI-cr) was adopted to evaluate air quality policies in this study. To investigate priorities of cross-administrative region air quality policies, the HI-cr were calculated by using annual results of atmospheric modeling and air quality modeling, which involved the meteorological effect and spatial distribution of air pollution. By studying the emission reduction targets of three administrative regions, Taichung, Changhwa, and Nantau in the Central Taiwan, 8 reduction scenarios were designed and examined. It is found that HI-cr can present detailed information in human health.From the results of adaptability assessement based on health, the equal reduction of emission in present air quality policy gave the most concentration reduction area with lower HI-cr. But according to the analysis in different proportion of emission reduction scenarios, it found that emission reduced more in the most population region, even the concentration reduction is not the highest but HI-cr increased. According to the analysis of different emission reduction policies, this study suggests HI-cr is an important index to evaluate the air pollution control policies instead of considering the impact of air pollutant concentrations only, especially in cross-administrative regions.Implications: In this study, we present a modified health index, HI-cr, to determine the priority of cross-administrative air quality policies using PM_2.5 concentration reduction. HI-cr is adaptable for any types of geography, in particular for areas where the air quality is almost attainment like Taiwan. Cross-administrative air quality policies could be evaluated using HI-cr, it could highlight the high performance on population health improvement rather than high concentration reduction. In particular, for economies where the air quality is almost attainment and with complex terrain and dense population, air quality policies should consider the health prevention issues.

The Complexity of Space Utilization and Environmental Pollution Control in the Main Corridor of Makassar City, South Sulawesi, Indonesia

Population mobility, increasing demand for transportation, and the complexity of land use have an impact on environmental quality degradation and air quality pollution. This study aims to analyze (1) the effect of population mobility, increased traffic volume, and land use change on air quality pollution, (2) direct and indirect effects of urban activities, transportation systems, and movement patterns on environmental quality degradation and air pollution index, and (3) air pollution strategy and sustainable urban environmental management. The research method used is a sequential explanation design. Data were obtained through observation, surveys, in-depth interviews, and documentation. The results of the study illustrate that the business center and Daya terminal with a value of 0.18 µgram/m3 is polluted, the power plant and Sermani industrial area with a value of 0.16 µgram/m3 is polluted, the Makassar industrial area with a value of 0.23 is heavily polluted, and the Hasanuddin International Airport area with a value of 0.04 µgram/m3 is not polluted. Population mobility, traffic volume, and land use changes have a significant effect on environmental quality degradation, with a determination coefficient of 94.1%. The direct effect of decreasing environmental quality on the air pollution index is 66.09%. This study recommends transportation management on the main road corridor of Makassar City, which is environmentally friendly with regard to sustainable environmental management.

Beyond Strict Regulations to Achieve Environmental and Economic Health-An Optimal PM2.5 Mitigation Policy for Korea

Growing concern about particulate matter (PM_2.5) pressures Korea to reduce the health risks associated with its high dependency on fossil fuels. The Korean economy relies heavily on large thermal power plants—a major source of PM_2.5 emissions. Although air quality regulations can negatively impact local economies, the Korean government announced two strict air quality mitigation policies in 2019. We develop a regional static computable general equilibrium model to simulate the economic and environmental impacts of these polices under alternative hypothetical scenarios. We separate two regions, Chungcheongnam-do, the most polluted region, and the rest of the country, in our model. As policy options, we introduce a regional development tax and a tradable market for PM emission permits, similar to an air pollution tax and a carbon permits market, respectively. The results show that allowing higher tax rates and a tradable permits market gives the optimal combination, with the PM_2.5 emissions reduced by 2.35% without sacrificing economic growth. Since alternative options present, for example, a 0.04% loss of gross domestic product to reduce PM emissions by the same amount, our results here may present a new policy paradigm for managing air pollutants such as PM_2.5.

Implications of Low Carbon City Sustainability Strategies for 2050

Cities and urban areas are critical nodes of societal resource flows, responsible for both global and local sustainability implications. They are complex systems and understanding the implications of potential actions by cities is critical for progress towards sustainability. In this paper the future implications of sustainability strategies are assessed for 10 European cities by comparing two scenarios for 2050: a business-as-usual (BAU) and a post-carbon/sustainability scenario (PC2050) (generated by city stakeholders). The effects of the scenarios are assessed using a mixed methodology: a semi-quantitative sustainability indicator analysis, energy and greenhouse gas (GHG) emissions (both production-based and consumption-based accounting (PBA and CBA)), land-use spatial modelling, and cost–benefit analysis. The paper highlights the clear benefits of PC2050 with improved sustainability indicator results, reduced land sprawl (which averages 16% in BAU) and positive cost–benefit results. Nonetheless, inequality and segregation are a common concern. In addition, whilst PBA indicates a significant decrease (average decrease from 4.7 to 1.3 tCO2eq per capita) CBA demonstrates rising overall emissions from an average of 11 to 14.8 tCO2eq per capita. This is linked to rising affluence and consumption trends despite local improvements in GHG emissions, which highlights a need for cities to address consumption-based emissions.

The Alerting Effect from Rising Public Awareness of Air Quality on the Outdoor Activities of Megacity Residents

This study investigated how the public awareness of air quality affects people’s decisions to participate in outdoor activities. Given that the keyword search volume of particulate matter (PM) in Seoul, South Korea started to grow dramatically only after November 2013, we defined two periods (low and high public awareness of PM) and conducted a series of comparative analyses to investigate the impact of public awareness of air quality on the relationship between PM level and people’s outdoor activities. In the low public awareness period, people’s outdoor activities measured by the number of daily subway passengers did not significantly vary over PM levels, even in the ’unhealthy’ range (80 < PM10 < = 150 µg/m3). On the contrary, during the high awareness period, people’s activities were significantly affected by the PM level, even in the ’moderate’ range. Specifically, the perceived safety threshold of PM10 level that people use to decide for engaging outdoor activities has decreased from 120 to 70 µg/m3. These results suggest that public awareness of air quality and its harmful ramifications on health is a key determinant of outdoor activities rather than PM10 concentration itself. Thus, this study alludes to a need for more timely and effective dissemination of air quality information to the public as much as for curbing anthropogenic emissions.

Fuel modification based on some metals compounds and their environmental impact

The history of fuel additive use reflects the interplay between chemistry, technology and public health concerns related to environmental effects. Decisions to use specific type of chemical modification during combustion process have been made in the absence of toxicological data on health and environmental effects or exposure. The influence of these important issues has extended globally, and the effects of various compositions impact for decades after the removal of these compounds. Fuel modifications are widely used for petrol, oil and solid fuels. According to market screening and literature review, additives containing some dangerous compounds are still in used today. Pb(C2H5)4 was used for long time as fuel additive and is still used as an additive in some grades of aviation gasoline, and in some developing countries. It is obvious that additives containing copper, lead and cerium should be replaced by organic substitutes or inorganic oxidizers during combustion processes.

Recent increase of surface particulate matter concentrations in the Seoul Metropolitan Area, Korea

Recent changes of surface particulate matter (PM) concentration in the Seoul Metropolitan Area (SMA), South Korea, are puzzling. The long-term trend of surface PM concentration in the SMA declined in the 2000s, but since 2012 its concentrations have tended to incline, which is coincident with frequent severe hazes in South Korea. This increase puts the Korean government’s emission reduction efforts in jeopardy. This study reports that interannual variation of surface PM concentration in South Korea is closely linked with the interannual variations of wind speed. A 12-year (2004–2015) regional air quality simulation was conducted over East Asia (27-km) and over South Korea (9-km) to assess the impact of meteorology under constant anthropogenic emissions. Simulated PM concentrations show a strong negative correlation (i.e. R = −0.86) with regional wind speed, implying that reduced regional ventilation is likely associated with more stagnant conditions that cause severe pollutant episodes in South Korea. We conclude that the current PM concentration trend in South Korea is a combination of long-term decline by emission control efforts and short-term fluctuation of regional wind speed interannual variability. When the meteorology-driven variations are removed, PM concentrations in South Korea have declined continuously even after 2012.