Aerosol and Air Quality Research, 16: 2227–2236, 2016
Copyright © Taiwan Association for Aerosol Research
ISSN: 1680-8584 print / 2071-1409 online
doi: 10.4209/aaqr.2016.08.0346
Characteristics of Respirable Particulate Metals Emitted by a Beehive Firework
Display in YanShuei Area of Southern Taiwan
Chih-Chung Lin
1
, Jen-Hsiung Tsai
1
, Kuo-Lin Huang
1
, C. Kuei-Jyum Yeh
1
, Hsiu-Lin Chen
2**
,
Shui-Jen Chen
1*
, Jia-Twu Lee
1
, Yi-Chin Hsieh
1
1
Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Nei-
Pu, Pingtung 91201, Taiwan
2
Department of Industrial Safety and Health, Hung Kuang University, Taichung 43302, Taiwan
ABSTRACT
This study investigates metals in the PM
1.0
and PM
2.5
collected using a micro-orifice uniform deposition impactor
(MOUDI) sampler in the YanShuei area of southern Taiwan during a beehive firework display. The results of sample
analyses indicate that during the beehive firework display, the ratios of metal concentrations in PM
2.5
(D) to the
background level (B) at leeward sampling site were 1,828 for Ba, 702 for K, 534 for Sr, 473 for Cu, 104 for Mg, 121 for
Al, and 98 for Pb. The corresponding data for PM
1.0
were 3036, 838, 550, 676, 594, 190, and 126, respectively. According
to the results of metal composition ratio, Principal Component Analysis (PCA), and upper continental crust (UCC)
analyses, the concentrations of particle-bound Al, Ba, Cu, K, Mg, Pb, and Sr increased during the beehive firework
displays, suggesting that firework-display aerosols contained abundant metal elements of Al, Ba, Cu, K, Mg, Pb, and Sr.
Before (background), trial, during, and after the beehive firework display, the Ba, K, Cu, Mg, Pb, and Sr (commonly
regarded as firework display indicator elements) accounted for 0.520, 2.45, 26.4 and 0.849% mass of PM
1
, respectively,
while for PM
2.5
the corresponding data were 0.777, 2.32, 23.8, and 0.776%, respectively.
Keywords: Beehive fireworks display; PM
1
; PM
2.5
; Metals; Short-term pollution.
INTRODUCTION
The short-term effects of air pollution on health have
attracted increasing attention in recent years. The extensive
use of pyrotechnics in large celebratory events frequently
degrades short-term air quality significantly, possibly
harming human health (causing chronic lung diseases, cancer,
neurological and haematological diseases, for example)
(Smith and Dinh, 1975; Clark, 1997; Godri et al., 2010;
Moreno et al., 2010; Caballero, et al., 2015; Robles, et al.,
2015). Fire work displays are known to increase ambient fine
particle concentrations and fine-particulate metals (Vecchi et
al., 2008; Lancaster et al., 1998; Perry, 1999; Kumara et
al., 2016). The complex nature of the particles that are
emitted during fireworks may have adverse health, effects
as reported by Ravindra et al. (2001). Furthermore, in the
*
Corresponding author.
Tel.: +886-8-7740263; Fax: +886-8-7740256
E-mail address: chensj@mail.npust.edu.tw
**
Corresponding author.
Tel.: +886-4-2631-8652
E-mail address: hsiulin@sunrise.hk.edu.tw
2007 Montréal International Fireworks Competition, PM
2.5
levels of 10,000 µg m
–3
were reached, equal to approximately
roughly 1,000 times the background level (Alexandre et
al., 2010). Zhang et al. (2010) reported the measurement
of the number concentrations and size distributions of aerosol
particles with aerodynamic diameters in the range of 10 nm to
10 µm during the Chinese New Year’s firework event in
Shanghai, China. Particle concentrations during the peak
hour of firework celebrations were approximately three
times higher than on the preceding day, with a clear shift in
the particles from nuclei mode (10–20 nm) and Aitken
mode (20–100 nm) to accumulation mode (0.5–1.0 µm).
More than 10 million firecracker/firework rockets displayed
in the Lantern festival night every year in the YanShuei area.
Therefore, the firecracker/firework display emitted abundant
PM
2.5
at the short-term. However, the mass concentrations
and chemical compositions (metal components/concentrations)
of PM
1.0
, PM
2.5
, and PM
10
from beehive firework displays
have seldom been investigated. Accordingly, this study
investigates the mass concentrations in PM
1.0
, PM
2.5
, and
PM
10
, as well as the metal components (Al, Ba, Ca, Cr, Cu,
Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn) and concentrations
in particles that were collected in the YanShuei area of
southern Taiwan. The size distributions and cumulative
mass fractions of metals in particles in each size range are
Lin et al., Aerosol and Air Quality Research, 16: 2227–2236, 2016
2228
obtained from the samples that were collected using a
MOUDI sampler. The results of an analysis show that a
beehive firework display emits significant amounts of PM
1
and PM
2.5
degrading, short-term air quality, requiring that
related health concerns be addressed.
MATERIALS AND METHODS
Collection of Particulates
Atmospheric particulate samples were collected in the
YanShuei area of southern Taiwan during the Lantern
Festival from February 21 to 25 in 2013. The windward
sampling site was located on the roof of a three-story
building (9 m height) in the Wumiao Temple, roughly 50 m
north to the major beehive fireworks display site, while the
leeward sampling site was located on the roof of a four-
story building (12 m height) in the YanShuei police station,
roughly 300 m south to the major beehive fireworks display
site. The YanShuei beehive fireworks display events occurred
within the four stages of our experimental periods. In this
investigation, it is regarded that February 21
st
–22
nd
, 23
th
–
24
th
, 24
th
(18:00–24:00), and 25
th
2013 were the before
(background), trial, during, and after beehive fireworks
display periods, respectively. The mean air temperature,
relative humidity, and wind speed were 19.1°C (14.4–26.4°C),
78.9% (56.0–94.0%), and 0.54 (0.0–2.2) m s
–1
, respectively,
during the sampling period (without any rain).
A MOUDI (Model No.100; MSP Co., Minneapolis, MN)
sampler equipped with Teflon filters (with diameters of 37
mm) was used to collect size-resolved aerosol samples. These
impactors effectively separated the particulate matter into
10 ranges (at 50% efficiency) with the following equivalent
cut-off aerodynamic diameters; 18–10, 10–5.6, 5.6–3.2,
3.2–1.8, 1.8–1.0, 1.0–0.56, 0.56–0.32, 0.32–0.18, 0.18–0.1,
and 0.1–0.056 µm. Accordingly, the particles were divided
into three size groups - PM
10
, fine (PM
2.5
), and accumulation
(PM
1.0
) particles. The sampling flow rate for the MOUDI
was 30 L min
–1
.
Silicon grease was applied to the surface of each filter
installed in the MOUDI sampler, and the greased filter-
strips were baked in a 60°C oven for 90 min to stabilize the
silicon grease before sampling to minimize particle bounce
between the different stages of the MOUDI during the
sampling. Before and after each sampling, the filters were
dried for 24 h in a desiccator at 25°C in 40% relative
humidity. They were then weighed on an electronic balance
(AND HM202) with a resolution of 10 µg. The suspended
particulate matter concentration was determined by dividing
the particle mass by the volume of sampled air.
Metals Analysis and Quality Control
Metals Analysis by Inductively Coupled Plasma-Optical
Emission Spectrometer (ICP-OES) Particles were digested
in a 1,600 W microwave oven (Mars, microwave digestion
system, CEM) according to Yang and Swami (2007) and
Tsai et al. (2003) to ensure accurate and reliable analysis of
metals in the particles. The digested solution was a mixture
of 10.0 mL (65% HNO
3
and 37% HCl) for Teflon filters.
All reagents were prepared using chemicals supplied by
Merck (Analytical grade). Inductively coupled plasma-
optical emission spectrometer (ICP-OES, ICP-OES Optima
2100DV, PerkinElmer) was used to analyze the metal
concentrations.
Analytical drift was monitored throughout the procedure.
Recovery efficiencies were determined and analyzed using
a diluted sample spiked with a known quantity of metal.
Recovery efficiencies from 93.7 to 100.8% were achieved.
The method detection limit (MDL) was estimated by
repeatedly analyzing a predefined quality control solution
and by replicate analysis in ICP- OES measurements, the
MDL of each element was calculated by MDL = 2.681 ×
S
pooled
, with S
A
2
/ S
B
2
< 3.05. S
pooled
= [(6S
A
2
+ 6S
B
2
)/12]
0.5
,
where S
pooled
is the pooled standard deviation, S
A
the
standard deviation of the one of two prepared samples with
a bigger F-test value, and S
B
the standard deviation of the
other. The detection limits in ng m
–3
(calculated from MDL
× volume of analyte solution (25 mL)/average sampling
volume (40 m
3
)) were 16.8, 0.113, 0.719, 0.96, 2.35, 0.264,
0.066, 0.042, 0.154, 0.313, 0.047, 0.033, 0.050, and 0.018
for Na, Mg, Al, K, Ca, Fe, Cr, Ni, Zn, Sr, Ba, Pb, Mn, and
Cu, respectively.
RESULTS AND DISCUSSION
Concentrations of Metals in PM with Various
Aerodynamic Diameters before and after Beehive
Firework Display
Tables 1 and 2 present the concentrations of metals in
particles before (background), on the rooftop of the Wumiao
Temple (windward) and YanShuei police station (leeward)
during and after a beehive firework display as part of the
2013 YanShuei Firework Festival. The mass concentration
of PM
2.5
increased from 28.2 µg m
–3
(background) to 437
µg m
–3
during the beehive display on the leeward side, and
from 26.1 µg m
–3
to 165 µg m
–3
on the windward side. At the
windward sampling site, the PM
2.5
and PM
10
concentrations
during the display reached approximately 4.7 and 4.9 times
the background values, respectively, whereas at the leeward
site, they were 12.5 and 4.6 times the national standards (35
and 125 µg m
–3
, respectively). Joly et al. (2010) reported
that the highest PM
2.5
levels during the 2007 Montréal
International Fireworks Competition were almost 10,000
µg m
–3
, which is approximately 1,000 times the background
level.
Before beehive firework display (background), the total
mean concentrations of 14 metals in PM
1.0
, PM
2.5
, and PM
10
particles were 349, 1016, and 3431 ng m
–3
, respectively, at
the leeward site and 2085, 2971, and 3785 ng m
–3
,
respectively, at the windward site. The major metals (30–
100 ng m
–3
) in PM
1.0
, PM
2.5
, and PM
10
were Al, Ca, Fe, K,
Na, and Zn (crustal metals and the metallic constituents of
sea salt). During the displays, the metals that were generated
at high concentration (≥ ~10
3
ng m
–3
) were Al, Ba, Cu, K,
Na, and Sr. During the beehive firework display, the
concentrations of metals in PM
2.5
(D) at leeward sampling
site rise above the background level (B) to degrees that
decrease in the order Ba (1,828 times), K (702 times), Sr
(534 times), Cu (473 times), Mg (104 times), Al (121
Lin et al., Aerosol and Air Quality Research, 16: 2227–2236, 2016
2229
Table 1. Concentrations of metals in PM
1.0
, PM
2.5
, and PM
10
at the leeward sampling site.
Particle
size
Sampling
period
PM
(µg m
–3
)
Metals concentration (ng
m
–3
)
Al Ba Ca C
r
Cu Fe
K
Mg Mn Na Ni Pb Sr Zn
PM
1.0
Backgroun
d
20.9 30.27 0.9719 31.04 2.944 1.615 52.31 87.09 9.822 3.073 65.73 2.873 7.025 2.115 51.89
Trial 77.9 621.0 48.83 316.9 28.94 21.17 488.3 1637 125.6 20.60 786.6 24.24 74.65 4.094 274.6
During 321 5761 2951 164.6 44.12 1092 319.4 72977 5830 79.41 1237 4.518 883.1 1163 980.0
After 43.5 73.79 9.306 2.532 4.726 7.110 102.8 271.3 55.69 5.286 75.91 4.079 22.75 2.990 120.1
PM
2.5
Background 28.2 62.69 2.082 83.80 4.368 3.006 126.2 126.2 73.36 6.284 400.3 3.241 11.76 2.745 109.5
Trial 120 1045 58.96 801.9 112.4 23.62 1019 2025 567.3 41.29 1896 29.62 96.11 12.51 517.5
During 437 7603 3805 462.7 58.31 1421 634.7 88637 7636 110.2 2133 5.559 1150 1466 1249
After 107 190.8 23.47 108.1 7.028 14.77 286.4 537.7 193.7 16.61 481.8 5.003 52.23 8.391 312.7
PM
10
Background 40.6 209.8 4.559 300.7 6.509 16.49 358.1 217.2 313.3 11.92 1716 60.53 40.68 4.601 170.8
Trial 181 1522 66.67 1550 199.2 24.33 1613 2403 1223 55.46 4962 33.35 111.2 19.10 721.1
During 572 11001 4601 2134 69.94 1611 1712 98807 9662 150.8 5571 7.984 1198 1596 1405
After 163 788.6 51.97 889.9 11.21 25.31 983.1 944.6 861.7 35.58 2401 6.364 63.57 20.21 462.8
Table 2. Concentrations of metals in PM
1.0
, PM
2.5
, and PM
10
at the windward sampling site.
Particle
size
Sampling
period
PM
(µg m
–3
)
Metals concentration (ng
m
–3
)
Al Ba Ca C
r
Cu Fe
K
Mg Mn Na Ni Pb Sr Zn
PM
1.0
Backgroun
d
17.4 128.6 3.252 393.2 2.159 10.25 161.5 615.6 134.8 43.97 444.0 11.56 20.50 1.893 114.2
Trial 30.6 54.20 1.803 90.64 2.159 9.840 67.71 154.0 18.63 13.61 225.3 3.808 20.03 1.144 70.03
During 120 765.3 167.2 698.9 16.32 86.12 211.7 9744 718.1 113.1 408.5 14.37 85.17 115.6 146.3
After 45.7 81.57 9.026 227.9 4.388 11.70 101.0 977.7 108.9 27.79 87.27 12.47 33.96 3.000 90.58
PM
2.5
Backgroun
d
26.1 190.8 4.109 556.3 3.055 12.34 253.9 697.1 212.0 65.27 784.1 14.65 24.93 2.620 149.7
Trial 46.1 125.5 3.646 194.7 4.737 16.35 181.0 224.1 109.3 19.43 598.0 4.704 27.08 2.609 165.8
During 165 1011 222.3 1010 19.76 123.9 432.2 8104 1010 142.1 1047 20.15 122.2 140.7 250.2
After 103 169.4 24.14 398.5 5.713 21.87 259.9 1251 222.5 35.24 570.0 15.61 64.36 7.972 238.3
PM
10
Backgroun
d
45.4 262.3 4.910 731.7 4.237 14.44 374.0 764.2 281.6 84.70 1041 18.98 27.78 3.352 172.1
Trial 85.4 388.4 7.033 684.9 6.190 22.69 537.0 348.6 461.1 33.22 1864 6.191 30.36 6.013 316.9
During 222 1746 250.8 1863 26.15 156.0 1064 6775 1801 252.8 4088 32.48 146.8 154.0 334.4
After 148 475.6 33.82 1063 7.829 28.12 706.4 1463 613.9 53.94 2352 20.15 77.39 13.68 316.3
Lin et al., Aerosol and Air Quality Research, 16: 2227–2236, 2016
2230
times), and Pb (98 times). The corresponding data (D/B)
for PM
1.0
were Ba (3,036 times), K (838 times), Cu (676
times), Mg (594 times), Sr (550 times), Al (190 times), and
Pb (126 times). In recent years, demand for fireworks of
multiple colors has considerably increased the use of metals
as color developers. Accordingly, during the beehive firework
display, the mass concentrations of Ba (green coloring
agent), Sr (red), Cu (blue) (Kulshrestha et al., 2004; Wang
et al., 2007; Moreno et al., 2007; Perrino et al., 2011) in
PM
2.5
at the leeward sampling site increased above their
background values (Ba: 2.082; Sr: 2.745; Cu: 3.006 ng m
–3
)
by 1828, 534 and 473 times, respectively (to Ba: 3,805; Sr:
1,466; Cu: 1,421 ng m
–3
) .
At the windward sampling site, the D/B values in PM
2.5
were, in decreasing order, Sr (×74), Ba (×68), K (×13), and
Cu (×12). The concentrations of Ba, K, Cu, Mg, and Sr in
the particulates were significantly higher at the leeward
site than at the windward site. Most investigations of
atmospheric PM emissions from fireworks have focused
on Sr, Ba, and K as tracers of firework emissions (Liu et
al., 1997; Kulshrestha et al., 2004; Drewnick et al., 2006;
Moreno et al., 2007; Wang et al., 2007; Barman et al., 2008;
Vecchi et al., 2008; Galindo et al., 2009; Joly et al., 2010).
Barium compounds (BaClO
3
and Ba(NO
3
)
2
) are used as
oxidizers. Both BaCO
3
and Ba(NO
3
)
2
are used to create
white effects or, in the presence of chlorine, bright green a
firework color that is mostly associated with Ba (Lancaster
et al., 1998; Perry, 1999). Potassium compounds (KNO
3
,
KClO
4
, and KClO
3
), which are used as propellants in
fireworks, are the main oxidizers: in a firework display.
Lin et al. (2014) found that the concentrations of Cl
–
in
PM
1.0
, PM
2.5
, and PM
2.5–10
during a display were 91, 64, and
6.9 times higher than their background values. Furthermore,
increases in measured K concentrations suggest that KClO
3
and KClO
4
are the major sources of oxygen in firecrackers.
Both SrSO
4
and Sr(NO
3
)
2
can be used as oxidizers, and,
along with carbonate, impart a red color to fireworks when
combined with chlorine. Finally, copper compounds such
as the copper chloride and copper oxide produce a blue
color, and can be mixed with strontium compounds to
produce purple effects. CuCr
2
O
4
is used as a catalyst in
rocket propellants (Lancaster et al., 1998). Although K, as
a black powder fuel that is combined with S, dominates
“special effect”trace additives can include various other
metals such as Al, Cu, Ti, or even Pb (Hickey et al., 2010).
Pb is of particular interest, given its high toxicity, as it is one
of the few metals/metalloids for which legal atmospheric
concentration limits exist (along with As, Hg, Ni, and Cd).
Nevertheless, in many countries, laws against the use of Pb
in the manufacture and combustion of fireworks are being
thwarted by imports from countries that are less concerned
with the potential health implications of their products.
Some fireworks continue to contain Pb levels that are
measurable in decigrams (Hickey et al., 2010). During a
beehive firework display, the total Pb in PM
10
was 1,198
ng m
–3
— higher than the air quality limit for Pb (500 ng m
–3
)
that has been set by the World Health Organization (WHO,
2000). In the present investigation, the Pb concentrations
in fine particles (1,150 ng m
–3
) and PM
1.0
(883.1 ng m
–3
)
were found to be 24 and 18 times those in coarse particles.
Therefore, the short-term exposure to firework sources
should be concerned for adverse health effects because it is
easier for fine-particulate Pb to enter and accumulate in the
human respiratory system than for coarse-particulate Pb.
Ratios (T/B, D/B, and A/B) (Ratios of Values of Particle-
Bound Metal Concentrations for Various PMs Before
(Background (B)), Trail (T), During (D), and After (A)
Beehive Firework Display of Particle-Bound metal
Compositions for Different PMs
According to Fig. 1, the D/B ratios of particle-bound Ba,
Cu, K, Mg, and Sr in PM
1.0
and PM
2.5
at the leeward
sampling site were significantly higher than T/B and A/B
during the beehive firework display. The maximal D/B
values of Ba were
198
and 118 in PM
1.0
and PM
2.5
during the
beehive fireworks display at that site. The D/B values for
PM
1.0
and PM
2.5
were lower at the windward site. The
maximal D/B value of Ba was 8.56 for PM
2.5
and the
maximal D/B value of Sr was 8.85 for PM
1.0
. The D/B values
of particle-bound Ca, Cr, Fe, Mn, Na, Ni, and Zn in PM
1.0
and PM
2.5
were less than corresponding T/B and A/B
values at both leeward and windward sites. (Notably, the
ratios for the metals compositions were all between zero
and two.) This finding suggests that concentrations of
particle-bound Al, Ba, Cu, K, Mg, Pb, and Sr increased
during the beehive firework display, suggesting that firework
aerosols are rich in Al, Ba, Cu, K, Mg, Pb, and Sr.
The above inference was examined by comparing the metal
concentration distributions normalized to the concentrations
of the upper continental crust (UCC) (Weckwerth, 2001) for
the differently sized particles at the leeward and windward
sampling sites during the sampling period (Fig. 2). The
sampled PM
1.0
, PM
2.5
, and PM
10
particles all exhibited
similar distributions of concentrations of the crustal metals
(Al, Ca, Fe, Mg, and Na), normalized to UCC, for the trial,
during, and after a beehive fireworks display at the leeward
and windward sites; furthermore, these patterns were also
similar to the background. Interestingly, the relative
abundances of Ba, Cu, K, Pb, and Sr in PM
1.0
and PM
2.5
during the beehive firework display at the leeward site
were very different to the background abundances, indicating
that the beehive firework display emited more of these five
metals in PM
1.0
and PM
2.5
. The concentrations of these five
metals in PM
1.0
and PM
2.5
, relative to those in the UCC, in
the trial, during, and after the beehive firework display at
the windward site were close to the background values.
Size Distributions of Particulate Metals before and after
the Beehive Firework Display
Fig. 3 presents the size distribution of particles of the major
metals (Ba, K, Cu, Mg, Pb, and Sr) during four periods
during the sampling period (February 21
st
–22
nd
, 23
th
–24
th
,
24
th
(18:00–24:00), and 25
th
, 2013 , which were before
(background), trial, during, and after the beehive firework
display, respectively). The results in the figure demonstrate
that, at the leeward sampling site, the major metals exhibited
approximately bi-modal size distributions with primary
peaks in the 0.56–1.0 µm range and secondary peaks in the
Lin et al., Aerosol and Air Quality Research, 16: 2227–2236, 2016
2231
Leeward (PM
1.0
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
10
20
30
40
50
60
200
T/B
D/B
A/B
Windward (PM
1.0
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
2
4
6
8
10
T/B
D/B
A/B
Leeward (PM
2.5
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
10
20
30
40
50
60
70
80
90
100
110
120
130
T/B
D/B
A/B
Windward (PM
2.5
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
2
4
6
8
10
T/B
D/B
A/B
Leeward (PM
10
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
20
40
60
80
100
T/B
D/B
A/B
Windward (PM
10
)
Metals
Al Ba Ca Cr Cu Fe K Mg Mn Na Ni Pb Sr Zn
Ratio of metal composition
0
10
20
30
40
50
60
70
T/B
D/B
A/B
Fig. 1. T/B, D/B, and A/B values and ratios of compositions of particle-bound metals in different particle size ranges at the
leeward and windward sampling sites (B: background; D: during beehive fireworks display; A: after the display).
coarse size range (3.2–5.6 µm) during the beehive firework
display. At the leeward sampling site, before the beehive
firework display (Background), the concentration of K
exhibited a bi-modal size distribution, but those of the
other major metals exhibited approximately single-modal
size distributions with major peaks in the coarse particle
range (3.2–5.6 µm). These distributions differed greatly
from those during the beehive firework display. The major
peaks in the size distribution of the metal particles clearly
shifted from coarse particles to fine particles during the