Topics: Particulate matter
Variation Characteristics of Particles Mass Concentration in Urban Air of
Changsha
Wang Qi*
Shanghai Research institute of Building Sciences(Group) Co,Ltd., Shanghai, China
*
Corresponding email:[email protected]
Keywords: particulate matter, mass concentration, PM10, PM2.5
1 Introduction
2 Methods
As the rapid developing of urbanization,
atmospheric pollution is very serious especial
particulate matter. Scientists and governments
pay more attention to particles all over the world,
as it would have the potential impacts on the
global climate change and the effect on the
health to human beings. Many epidemiological
studies showed that there was strong correlation
between the level of particle and human health.
The rise of particle concentration has lead to a
significant increase of morbidity and mortality
in respiratory and cardiovascular diseases.
( Brunekreef and Holgate, 2002; Samet et al.,
2000 )
The mass concentrations of particles were
measured in urban air of Changsha from
November 2007 to October 2008. The real-time
mass concentrations of PM10 were measured
using a TEOM monitor (50℃, R&P 1400a). The
TSI Model 8520 DustTrak aerosol monitor with
a 2.5μm inlet was used to measure the real-time
approximation of PM2.5 concentration. The
PM2.5 values obtained using this instrument
which operates based on a light scattering
technique were not actual gravimetric values. In
order to obtain values close to true PM2.5 from
the data collected by the DustTrak, an additional
experiment was conducted under laboratory
conditions to compare the DustTrak data with
the data of TEOM. Based on the results of this
additional experiment, the following liner
regression equation was obtained:
The communique of environment in Hunan
province 2007
reported re-suspension of
particles was main atmospheric pollutant
especially PM10, the average annual
concentration of PM10 was higher than the limit
Ⅱof National Air Quality Standard in Changsha.
The main aim of this study was to investigate
variation characteristics of particles mass
concentration in urban air of Changsha.
PM2.5 (TEOM) = 0.367 PM2.5 (DustTrak) 8.428 (1)
(with R2 = 0.90)
Morawska et al. (2003) also conducted the same
comparison study. All statistical analyses were
conducted using a statistical analysis software
package-SPSS 13.0.
3 Results and Discussion
PM10 was primary atmospheric pollution in
Changsha and the concentration of PM10 was
high. Average diurnal concentrations of PM10
were 116.4±42.6μg/m3
122.3±46.1μg/m3
125.0±57.4μg/m3 in summer, autumn and
winter in Fig 1. Average diurnal concentrations
of PM10 were higher in autumn and winter than
concentration in summer. This can be explained
by the domestic use of coal fuels in autumn and
winter.
There was a correlation between indoor and
outdoor PM10 without indoor source and
correlation coefficients varied from 0.84 to 0.93
(p<0.01), showing that outdoor levels influenced
indoor concentrations. Finally, the relationship
between PM10 and PM2.5 was investigated.
PM10 concentration was strongly associated
with PM2.5 (p<0.01), as showed in Fig3. It was
suggested that PM2.5 was main part in PM10.
Fig.3. Relationship between PM10 and PM2.5.
Fig.1. Particle concentrations at different seasons.
Average diurnal variations of PM10 presented
two peaks in Fig 2. The morning peak hour was
at about 8-10 a.m. and the evening peak hours at
5-7 p.m. The phenomena mainly attributed to
traffic emission and meteorological parameters.
Mönkkönen et al., 2004 also found the similar
effect in New Delhi.
4 Conclusions
In the past ten years, particulate pollution was
mainly caused by coarse particle. The
government focused on PM10 and established
Ambient air quality standard. However, recent
years, PM2.5 has been received more attention
because of local traffic. Much future research on
PM2.5 will be essential.
5 References
Brunekreef B., Holgate S.T., Air pollution and health.
Lancet, 2002, 360: 1233-1242.
Samet J.M., Dominici F., Curriero F.C., et al. Fine
particulate air pollution and mortality in 20 US cities.
1987-1994, New England Journal of Medicine, 2000,
343: 1742-1749.
Morawska L., He C., Hitchins J., et al. 2003.
Characteristics of particle number and mass
concentrations in residential houses in Brisbane,
Australia. Atmospheric Environment, 2003, 37(30),
4195-4203.
Fig.2. Average diurnal variation of PM10 concentrations.
Mönkkönen P, Uma R, Srinivasan D, et al.
Relationship and variations of aerosol number and
PM10 mass concentrations in a highly polluted urban
environment – New Delhi, India. Atmospheric
Environment,2004,38(3): 425-433.