Severe Aerosol Pollution Derived from Fireworks: A Case in Jinan, China
- 1. Environment Research Institute, School of Environmental Science and Engineering, Shandong University, Jinan, China
- 2. Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai, China
INTRODUCTION
Fireworks were frequently displayed during ceremonies or festivals [1-5], which could cause both local and regional air pollution [6,7]. The concentration of atmospheric pollutants [8-10] and inhalable aerosol with a wide size range [11] would increase significantly, and has very obvious impact on air quality. However, the hourly-averaged concentration of inorganic pollutants synchronized to the particle size distribution related to firework events is not well studied. Here a case is shown the crucial impact of fireworks events on air quality with the rapid increases of chemical compositions and size concentration of aerosol derived from fireworks on the 2013 Chinese New Year and the Lantern Festival in Jinan, China.
EXPERIMENTAL
The sampling site was located on the ground monitoring station in the center campus of Shandong University (36.67ºN, 117.05ºE) in an urban area in Jinan. A MARGA ADI 2080 (Applikon-ECN, Netherlands) was used to monitor the hourlyaveraged concentration of SO2 and inorganic water-soluble ions in PM2.5. A Particulate Monitor 5030 (Thermo Scientific, USA), and CO analyzer 300E (Teledyne Technol., USA) were used to monitor the concentration of PM2.5 and CO, respectively. A WideRange Particle Spectrometer (Model 1000XP, MSP, USA) can on-line record the aerosol size distribution in the range of 5 nm ~10 μm. The ambient temperature and relative humidity were measured by a portable automatic meteorological station. The visibility was obtained from visibility instrument. The average temperature and RH were both blow 10o C and 60% during this field measurement, respectively.
THE MASS CONCENTRATION OF POLLUTANTS AND VISIBILITY
As KNO3 is the important composition in black powder of fireworks, K+ can be used as tracer of fireworks events. As shown in (Figure 1), the high concentration of K+ have been found during four serious fireworks events on Feb. 9 and Feb.10 (the Chinese New Year), and Feb. 24 (the Lantern Festival), respectively. The hourly-averaged mass concentration of PM2.5 and the hourly-averaged visibility were 100.8 μg m-3 and 7.43 km within 6 h before 16:00 on Feb. 9, respectively.
After a few hours, the values of PM2.5 and visibility rapidly changed to 873.6 μg/m3 and 1.1 km, respectively. The concentration of PM2.5 in the second event closed to the value at the first time, higher than that in the third and forth events and the visibility dropped sharply during each event. In addition, inorganic water-soluble ions can account for 69% of the total mass concentration of PM2.5 before the fireworks events, since then the value rose to 89% during the first event. The proportion of Cl- and metal ions in PM2.5 increased very obviously among them.
The mass concentration of K+ were used to do linear regression with pollution gas and PM2.5, water-soluble inorganic ions in the period of Feb. 9 10:00~16:00 and Feb. 24 14:00~18:00 (before the fireworks events), Feb. 9 18:00~Feb. 10 8:00 and Feb. 24 18:00~Feb. 25 0:00 (during the fireworks events), respectively. The values of R2 between K+ and SO2 , PM2.5 and Cl- , NO2 - , SO4 2-, Mg2+ in PM2.5 were all above 0.85. Compared with the 6 h average data before 16:00, their mass concentration between 21:00 and 23:00 increased 184, 11.1, 9.19, 226, 33.5, 9.52 and 169 times, respectively. The R2 between K+ , CO and Na+ were in range of 0.6~0.8, that multiple of CO and Na+ was 4.37 and 4.96, respectively.
AEROSOLS SIZE DISTRIBUTION
The number size distribution on Feb. 24 and 25 is shown in (Figure 2) as a contour plot. The most obvious characteristic of this plot is the high number concentrations of aerosols in range of 20~100 nm (Aitken nuclei modal) during the fireworks event (Feb. 24 18:00~Feb. 25 0:00), this period corresponded to the the event (Feb. 24 18:00~ Feb. 25 0:00) in (Figure 1). Compared with the 6 h average data before 17:00, the number concentration in range of 20~100 nm during the event increased 1.14 times, and then reduced rapidly after the event. So the results demonstrate that these aerosols in the Aitken nuclei modal were from firework events significantly changed the modal structure of aerosols size distribution, and can cause serious air pollution.
ATMOSPHERIC IMPLICATIONS
The hourly average mass concentration of inorganic air pollutants and aerosols size distribution were measured during the two Chinese traditional festivals (the Chinese New Year and the Lantern Festival) in 2013 in Jinan, China. The mass concentration of PM2.5 could rapidly increase during fireworks events. SO2 , CO and Cl- , NO2 - , SO4 2-, Na+ , K+ , Mg2+ in PM2.5 were primary emissions of combustion of black powder,these primary aerosols mainly concentrated in range of 20~100 nm (Aitken nuclei modal). The results demonstrate that firework events would aggravate the air pollution and changed the directly modal structure of aerosol size distribution, and lower the atmospheric visibility quickly. Fireworks events can produce a large number of containing sulfur pollutants and containing nitrogen pollutants, these pollutants may occur to a series of chemical reactions in atmosphere. The fireworks events can cause serious air pollution, so it is necessary to take some measures to reduce fireworks displays.
ACKNOWLEDGMENTS
This work was funded by the Taishan Scholars Grant (No. ts20120522), National Natural Science Foundation of China (Nos. 21190053, 21177025), Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB05010200) and FP7 project (AMIS, No.PIRSES-GA-2011). We are grateful for the help from Dr. Weijun Li for minor revision.