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ISSN : 1225-4517(Print)
ISSN : 2287-3503(Online)
Journal of Environmental Science International Vol.27 No.10 pp.925-931
DOI : https://doi.org/10.5322/JESI.2018.27.10.925

# Characteristics of PM10, PM2.5 and PM2.5/PM10 Ratio in Air Monitoring Stations in Gyeongnam

Jeong-Ho Park*, Jeong-Min Suh1)
Department of Environmental Engineering, Gyeongnam National University of Science and Technology
1)Department of Bioenvironmental Energy, Pusan National University
*Corresponding author: Jeong-Ho Park, Department of Environmental Engineering, Gyeongnam National University of Science and Technology, Jinju 52725, Korea
Phone : +82-55-751-3345
05/10/2018 29/10/2018 29/10/2018

## Abstract

The characteristics of PM10, PM2.5 and Ratio(PM2.5/PM10) of 11 urban air monitoring stations in Gyeongnam were analyzed for the last 3 years(’15~’17). The average of the all stations was PM10 45 μg/m3, PM2.5 24 μg/m3 and Ratio 0.54, and annual reduction rates were PM10 -2.9%, PM2.5 –2.7% and Ratio –1.2%, respectively. The seasonal characteristics of PM10 were spring 54 μg/m3 > winter 48 μg/m3 > summer/autumn 40 μg/m3, PM2.5 were spring/winter 26 μg/m3 > summer 23 > autumn 22 μg/m3 and Ratio were summer 0.56 > winter 0.55 > autumn 0.54 > spring 0.51, respectively. The hourly characteristics of PM10 were 11 μg/m3 higher than 09:00~12:00 at 03:00~06:00, PM2.5 were 6 μg/m3 higher than 09:00~12:00 at 17:00~18:00 and Ratio were 0.07 higher than 04:00~06:00 at 19:00. By site, the highest concentration of PM10 was YJ site 53 μg/m3 and PM2.5 was HW site 28 μg/m3. And Ratio at HD site showed the largest reduction from ’15 0.62 to ’17 0.52.

## 1. Introduction

Atmospheric Particulate Matter(PM) is generated by primary particles that are directly emitted from various sources, secondary particles generated through the conversion of gas to particles, and are continuously distributed in a particle size range of 0.01 to 100 μm. Many toxicological studies have reported that fine particles have a more toxic adverse effect than coarse particles, depending on the particle size(Donaldson et al., 1998; Harrison et al. 2010).

In Korea, Atmospheric environmental standards for PM10 and PM2.5, which have long-term prosperity and impact on health, have been established since 1993 and are monitored by the national air pollution monitoring network.

Coarse particles(PM10-PM2.5) are generated from natural sources such as mechanical fracturing, soil, and sea salt, and are quickly removed from the atmosphere through gravitational settling and rainfall washing. On the other hand, fine particles(PM2.5) is mainly generated from anthropogenic combustion sources including vehicles, and it is very difficult to control in terms of regional air quality control due to active inter-regional or long-distance transportation. Therefore, it is important to analyze temporal and spatial changes of the concentration ratio as well as the concentration characteristics in order to understand the behavior characteristics of PM10 and PM2.5(Munir, 2017).

Recently, fine particles have been attracting much attention not only in the atmospheric environment but also in terms of health damage. Especially, major cities such as Seoul and Busan are using the measurement data of the air pollution monitoring network to determine the effect of the local air pollution policy and the improvement of air quality. In Gyeongnam Province, the concentration of PM10 (45 μg/m3 ) and PM2.5 (25 μg/m3 ) in 2016 is similar or not significantly lower than the national average, Seoul and Busan(MoE, 2017). Nevertheless, there is little research on the characteristics of PM10 and PM2.5 in the region.

In this paper, at 11 air pollution monitoring stations where the PM2.5 is measuring in Gyeongnam area were collected PM10 and PM2.5 data for the last three years(15~17), and the temporal and spatial characteristics including the PM2.5/PM10 concentration ratio(Ratio) were analyzed.

## 2. Methodology

### 2.1. Air monitoring network in Gyeongnam

The air pollution monitoring network in Gyeongnam is shown in Fig. 1. As of the end of December 2017, there are a total of 25 monitoring stations in Gyeongnam, including 21 urban stations, 1 roadside station, and 3 suburban sites. Of these 11 urban stations, the PM2.5 measuring instrument has been installed since 2015 and measurement data are available. In 11 urban stations, the PM2.5 instrument has been installed and PM2.5 measurement data are available from 2015(MoE, 2018).

In this study, PM10 and PM2.5 data from the 11 urban stations were used. The eight sites such as the HW site(Hoewong-dong, Changwo) are located in the residential area, the GJ site(Gaeumjeong-dong, Changwo) and SD site(Sangdae-dong, Jinju) in the industrial area, and the HD site(Hadong-eup, Hadong) in the green area(KNHE, 2018).

### 2.2. Process PM10 and PM2.5 collection data

In this study, PM10 and PM2.5 data collected 26,304 final confirmed hourly concentration for the last 3 years(15~17) in 11 urban stations on Air Korea homepage(Air Korea, 2018). As shown in Table 1, the average 93% effective measurement data excluding the error data was used in this study.

The daily, monthly and annual average concentrations were calculated using the hourly data. The average concentrations were used only when the effective measurement rate was over 75%. The average concentration of PM10 and PM2.5 was rounded off to the first decimal place(MoE, 2016).

The collected data were statistically processed using the IBM SPSS Statistics program(Ver. 21).

### 2.3. Status of Asian dust and high concentration dust alarm

The high concentration of PM appears mainly in the case of Asian dust and fine dust alarm.

The occurrence days of Asian dust in Gyeongnam was based on the Changwon weather station(155) and occurred for a total of 13 days in the last 3 years including 4 days in 2015, 5 days in 2016 and 3 days in 2017(KMA, 2018).

The days with PM10 concentration of more than 150 μg/m3 over 2 hours appeared for total 8 days in the last 3 years including 3 days in 2015, 2 days in 2016 and 3 days in 2017. And the days with PM2.5 concentration of more than 90 μg/m3 over 2 hours appeared for total 8 days in the last 3 years including 8 days in 2015, 0 day in 2016 and 2017.

## 3. Results and discussion

### 3.1. Daily average change over the last three years

In order to investigate the overall tendency of PM concentration in Gyeongnam during the last 3 years(15~17), the daily mean characteristics of PM10, PM2.5 and Ratio(PM2.5/PM10) in 11 air monitoring stations are shown in Fig. 2.

The daily mean values for the last three years were PM10 45 μg/m3 , PM2.5 24 μg/m3 and Ratio 0.54(0.19 ~ 0.71), respectively.

The daily average of 13 days of Asian dust phenomenon occurrence was PM10 130 μg/m3 , PM2.5 37 μg/m3 and Ratio 0.32. The average of the PM10 alarm days for 8 days was PM10 126 μg/m3 , PM2.5 40 μg/m3 and Ratio 0.35. And the average of the PM2.5 alarms issued for 8 days only in 2017 were PM10 101 μg/m3 , PM2.5 58 μg/m3 and Ratio 0.58, respectively. On the other hand, in normal days except for Asian dust phenomenon and PM alarm days were PM10 44 μg/m3 , PM2.5 24 μg/m3 and Ratio 0.54.

In general, characterization of PM is evaluated at an annual average concentration, but it is important to focus on the occurrence of high concentration from the viewpoint of harmfulness(Kim, 2005). The days of high concentrations of PM10 and PM2.5 exceeding the 24-hour average environmental standard decreased annually. The days when PM10 concentration exceeded 100 μg/m3 appeared 15 8 days, 16 7 days and 17 3 days. It also appeared mainly during the period from February to May and during the occurrence of Asian dust. Therefore, it was shown that the Asian dust phenomenon that appeared mainly in spring had a great influence on the occurrence of high concentration of PM10. The days when PM2.5 concentration exceeded 50 μg/m3 appeared a total 23 days such as 15 9 days, 16 10 days and 17 4 days. When the new modified environmental standard PM2.5 of 35 μg/m3 was applied, it was a total 140 days such as 15 55 days, 16 51 days and 17 34 days. Especially, the days of winter and spring were two times higher than those of summer and autumn.

The concentration ratio of PM2.5 in PM10, Ratio is a key indicator of contribution of PM source. When this value is high, the contribution of secondary particles converted from gas to particles is high. When it is low, the contribution of primary particles such as soil particles and road fugitive dust is high(Querol et al., 2004; Jeong and Hwang, 2014; Munir, 2017).

In the last three years, the Ratio has appeared in a very wide range between 0.19 and 0.71. By year, Ratio were 15 0.55(0.20~0.70), 16 0.54(0.26~0.71) and 17 0.53(0.19,~0.71). And seasonal variations were 0.56(0.31~0.70) in summer, 0.55(0.20~0.71) in winter, 0.54(0.27~0.70) in autumn and 0.51(0.19~ 0.69) in spring.

### 3.2. Monthly and hourly change characteristics

Fig. 3 shows average trends of PM10, PM2.5 and Ratio in 11 air monitoring stations by monthly and time series for the last 3 years.

The monthly average concentration of PM10 was the highest at March and May 55 μg/m3 , and the lowest at September 35 μg/m3 . The seasonal characteristics of PM10 were in order of 54 μg/m3 in spring, 48 μg/m3 in winter, and 40 μg/m3 in summer and autumn. The monthly average concentration of PM2.5 was the highest at 29 μg/m3 in March, and the lowest at 20 μg/m3 in from September to October. The seasonal characteristics of PM2.5 were in order of 26 μg/m3 in spring and winter, 23 μg/m3 in summer and 22 μg/m3 in autumn. The monthly average of Ratio was the highest at June 0.58, and the lowest at April 0.47. The seasonal characteristics of Ratio were in order of 0.56 in summer, 0.55 in winter, 0.54 in autumn and 0.51 in spring. In particular, the monthly maximum concentration difference was 20 μg/m3 for PM10, 8 μg/m3 for PM2.5 and 0.10 for Ratio, respectively.

The hourly average concentration of PM10 was the highest 50~52 μg/m3 at 09:00~12:00 and the lowest 41~42 μg/m3 at 03:00~06:00. And 24-hour maximum concentration difference was 11 μg/m3 . The concentration of PM2.5 was the highest 27~28 μg/m3 at 09:00~12:00 and the lowest 22 μg/m3 at 17:00~18:00. And 24-hour maximum concentration difference was 6 μg/m3 . Ratio was the highest 0.57 at 04:00~06:00 and the lowest 0.50 at 19:00. And 24-hour maximum Ratio difference was 0.07.

### 3.3. Characteristics of 11 monitoring sites

Table 2 shows the annual average trends of PM10, PM2.5 and Ratio for the last 3 years(15~17) for 11 sites.

Overall, the average concentration of PM10 at all sites decreased from 15 47 μg/m3 to 17 43 μg/m3 , and 4 μg/m3 during the last 3 years and -2.9% per year. The concentration of PM2.5 decreased from 15 25 μg/m3 to 17 23 μg/m3 , and 2 μg/m3 during the last 3 years and -2.7% per year. The concentration of PM2.5 decreased from 15 25 μg/m3 to 17 23 μg/m3 , and 2 μg/m3 during the last 3 years and -2.7% per year. For Ratio decreased from 15 0.55 to 17 0.53, and 0.02 in the last 3 years and -1.2% per year.

By site, the PM10 concentration at YJ site was 53 μ g/ , and higher 8 μg/m3 than the average. And the PM2.5 concentration at HW site was 28 μg/m3 , higher 4 μg/m3 than the average. On the other hand, the SC site had PM10 38 μg/m3 , and lower 7 μg/m3 than the average and PM2.5 19 μg/m3 , and lower 5 μg/m3 than the average. On the other hand, the SC site was the lowest concentration of PM10 38 μg/m3 and PM2.5 19 μg/m3 . In the case of the SD site located in the industrial area, the PM10 concentration decreased from 15 55 μg/m3 to 17 44 μg/m3 and PM2.5 concentration decreased from 15 28 μg/m3 to 17 21 μg/m3 . The SD site was the high decreasing tendency among 11 sites.

The Ratio by site was in the order of HW site 0.60 > GH site 0.58 > AJ site 0.57 > SB site 0.56 > JY and HD site 0.55> BB site 0.52> GJ and SC site 0.51 > SD site 0.49 > YJ site 0.47.

In particular, HD site showed the largest reduction by site, with 0.62 in 15, 0.53 in 16 and 0.52 in 17.

Due to the Asian dust phenomenon, the annual concentration of PM10 increased by about 1 μg/m3. However, there was no change in PM2.5 and Ratio.

## 4. CONCLUSIONS

For PM reduction plans in Gyeongnam, PM10 and PM2.5 data in 11 air monitoring stations for the past 3 years(15~17) were collected and analyzed. The results of the analysis are as follows.

The annually average of all the stations for 3 years was PM10 45, PM2.5 24 and Ratio 0.54 and there were decreasing with PM10 -2.9%, PM2.5 -2.7% and Ratio -1.2% every year.

In the seasonal characteristics, PM10 concentration were in order of 54 μg/m3 in spring, 48 μg/m3 in winter, and 40 μg/m3 in summer and autumn. PM2.5 were in order of 26 μg/m3 in spring and winter, 23 μg/m3 in summer, and 22 μg/m3 in autumn. Ratio were in order of 0.56 in summer, 0.55 in winter, 0.54 in autumn, and 0.51 in spring.

In the 24-hour characteristics, PM10 concentration was the highest 50~52 μg/m3 at 09:00~12:00 and 24-hour maximum concentration difference was 11 μ g/m3. PM2.5 was the highest 27~28 μg/m3 at 09:00 ~12:00 and 24-hour concentration difference was 6 μ g/ . Ratio was the highest 0.57 at 04:00~06:00 and 24-hour difference was 0.07.

By site, PM10 concentration at YJ site was 53 μg/m3 , and higher 8 μg/m3 than the average. And the PM2.5 concentration at HW site was 28 μg/m3 , higher 4 μg/m3 than the average. The Ratio at HD site showed the largest reduction from 15 0.62 to 17 0.52.

## Figure

The location of air pollution monitoring stations in Gyeongnam, Korea, December 2017.

Daily variation of PM10, PM2.5 and PM2.5/PM10 for 11-site average in 3 years(15~17).

Monthly and hourly variation of PM10, PM2.5 and Ratio(PM2.5/PM10) for 11-site average in 3 years(15~`17).

## Table

The PM monitoring stations and effective rate of 1 hour measurement data

Changes over the last three year of PM10, PM2.5 and Ratio in the 11 sites

## Reference

1. Air Korea, 2018, http://www.airkorea.or.kr.
2. Donaldson, K. , Li, X. Y , MacNee, W. , 1998, Ultrafine(nanometre) particle mediated lung injury , Journal of Aerosol Science, 29(5/6), 553-560.
3. Gyeongnam Institute of Health & Environment(KNHE), 2018, Operational results of air pollution monitoring network in Gyeongnam.
4. Harrison, R.M. , Giorio, C. , Beddows, D.C. , Dall’Osto, M. , 2010, Size distribution of airborne particles controls outcomes of epidemiological studies , Sci. Total Environ., 409, 289-293.
5. Jeon, B. I. , Hwang, Y. S. , 2014, Characteristics of weekday/weekend PM10 and PM2.5 concentrations at Busan , J. Env. Sci. Intern., 23(7), 1241-1251.
6. Kim, Y. S. , 2005, Issues and tasks for air quality management in the greater seoul metropolitan area, Environmental policy, 4(1), 1-19.
7. Korea Meteorological Administration(KMA), 2018, http://www.kma.go.kr.
8. Ministry of Environment(MoE), 2016, Operation of establishment guideline of air pollution monitoring network.
9. Ministry of Environment(MoE), 2017, Annual report of air quality in Korea, 2016.
10. Ministry of Environment(MoE), 2018, Annual report of air quality in Korea, 2017.
11. Munir, S. , 2017, Analysing temporal trends in the ratios of PM2.5/PM10 in the UK , Aerosol and Air Quality Research, 17, 3448.
12. Querola, X. , Alastueya, A. , Ruiza, C. R. , Artinanob, B. , Hanssonc, H. C. , Harrisond, R. M. , Buringhe, E. , Brink, H. M. , Lutzg, M. , Bruckmannh, P. , Straehli, P. , Schneide, J. , 2004, Speciation and origin of PM10 and PM2.5 in selected European cities , Atmospheric Environment, 38, 65476555.