Post on 22-Sep-2020
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Kok Sothea and Nguyen Thi Kim Oanh
Environmental Engineering and ManagementSchool of Environment, Resources and Development
Asian Institute of Technology
POLYCYCLIC AROMATIC HYDROCARBON (PAHs) LEVELS AND CONTRIBUTING SOURCE IN PHNOM PENH, CAMBODIA
Presentation Itinerary
2
3 Sampling Locations and Sampling Plan
4 Results and Discussions
1 Background
2 Research Objective
5 Conclusions
• The sources and levels of Particulate Matter (PM) and PAHs emissions are both spatially and temporally varied.
• Several studies show that high concentrations of PAHs generally occur in urban areas especially in Asian developing countries.
• Several studies conducted in Cambodia, but they mainly focus on, coarse particles bound PAHs.
• No study has been found to focus on the fine particle-bound PAHs and gas bound PAHs in the country.
• The fine particle bound PAHs should be monitored to provide useful information on the contribution of the sources to the atmospheric PAHs and the associated health effects.
Background
3
To determine the ambient levels phase distribution of PAHs and contributing sources by receptor modeling in Phnom Penh
Sampling Locations
• Located in the city center
• Close to road site• 11 m above the
ground
Urban Traffic Site
Sub-urban
Residential Site
12
1
2
• Located in the sub-urban city
• 8 m above the ground
Population ~ 2 MVehicle ~ 1.2 M
Ambient Air Quality Sampling Plan
5
PAHs
Element
sIons
PAHs BC
Elements
Ions
BC
2 QFFs (47mm) Samples and 1 PUF for each PM2.5 and
PM10 at UT Site
PU
F PU
F
Cut into 4 parts
PM2.5 and PUF Sample at SR Site
PAHsPAHs
1st QFF 2nd QFFQFF (90mm)SR Site (URG-3000B) UT Site (URG-3000ABC)
PM2.5
PU
F
PM2.5PM2.5 PM10PM`10
PM2.5
PU
F
QFF (47mm), PUF (30mm)QFF (90mm), PUF (50mm)
• Sampling period: Feb 2016 to Jan 2017
• Sampling frequency: once/ 4 days (Dry)
and once/6 days (wet)
• Sampling duration: 24 hours
• Put in petri dish and conditions at (40 ± 5% RH, 22 ±
30C) of 24-hrs for QFF
• PUF refrigerated till extraction
PU
F
PM2.5PM2.5
PU
F
PM10PM`10
PM mass concentration by gravimetric/microblance
Pre-weight QFF and pre-clean PUF
PU
F
PU
F
GC-MS
24hr PM Levels in Phnom Penh
6
-
20
40
60
80
100
120
140
23-F
eb-1
6
4-M
ar-1
6
14-M
ar-1
6
24-M
ar-1
6
3-A
pr-
16
13-A
pr-
16
23-A
pr-
16
3-M
ay-1
6
13-M
ay-1
6
23-M
ay-1
6
2-J
un-1
6
12-J
un-1
6
22-J
un-1
6
2-J
ul-
16
12-J
ul-
16
22-J
ul-
16
1-A
ug-1
6
11-A
ug-1
6
21-A
ug-1
6
31-A
ug-1
6
10-S
ep-1
6
20-S
ep-1
6
30-S
ep-1
6
10-O
ct-1
6
20-O
ct-1
6
30-O
ct-1
6
9-N
ov-1
6
19-N
ov-1
6
29-N
ov-1
6
9-D
ec-1
6
19-D
ec-1
6
29-D
ec-1
6
8-J
an-1
7
PM
conc.
(µ
g/m
3)
PM2.5 (Urban)PM10 (Urban)
-
10
20
30
40
50
60
23-F
eb-1
6
4-M
ar-1
6
14-M
ar-1
6
24-M
ar-1
6
3-A
pr-
16
13-A
pr-
16
23-A
pr-
16
3-M
ay-1
6
13-M
ay-1
6
23-M
ay-1
6
2-J
un-1
6
12-J
un-1
6
22-J
un-1
6
2-J
ul-
16
12-J
ul-
16
22-J
ul-
16
1-A
ug-1
6
11-A
ug-1
6
21-A
ug-1
6
31-A
ug-1
6
10-S
ep-1
6
20-S
ep-1
6
30
-Sep
-16
10-O
ct-1
6
20-O
ct-1
6
30-O
ct-1
6
9-N
ov-1
6
19
-No
v-1
6
29-N
ov-1
6
9-D
ec-1
6
19-D
ec-1
6
29-D
ec-1
6
8-J
an-1
7
PM
conc.
(µ
g/m
3)
PM2.5 (Residential)
PM10: 15 to 119 µg/m3 (58 µg/m3)
PM2.5: 8 to 85 µg/m3 (36 µg/m3)
PM2.5: 7 to 53 µg/m3 (29 µg/m3)
Same Pattern over time
• Urban PM2.5:
22% >
Cambodia Standard (50 µg/m3)
• Residential
PM2.5: 6% >
Cambodia Standard
PAHs Levels in Phnom Penh
7
-
20
40
60
80
100
120
PPAHs GPAHs PPAHs GPAHs PPAHs GPAHs
PM2.5 PM10 PM2.5
Urban Residential
PA
Hs
(ng/m
3)
NAP AcPy ACE Flu PHE ANTFL PYR BaA CHY BbF BkFBaP IND DBA BghiP
• Urban:
• GPAHs (PM2.5): 96 ng/m3 74% of
TPAHs; PPAHs: 32 ng/m3
• GPAHs (PM10 ): 89 ng/m3 69% of
TPAHs; PPAHs: 43 ng/m3
• Residential: • GPAHs: 53 ng/m3 65% of TPAHs;
PPAHs :29 ng/m3
-
20
40
60
80
100
120
140
PPAHs GPAHs PPAHs GPAHs PPAHS GPAHs
PM2.5 PM10 PM2.5
Urban Resident
PA
Hs
Con. (n
g/m
3)
Seasonal PAHs Levels in PNH
8
• No significant differences
between the levels of PAHs in
dry and wet season
• local emission sources did
not significantly vary
between the two seasons.
• the traffic volume did not
fluctuate much by season
• Intensity of traffic
congestion was more
severe during the rainy
days compared to dry
days.
-
20
40
60
80
100
120
140
PM2.5 PM10 PUF PM2.5 PUF
Urban Residential
ng
/m3
Dry Season
Wet Season
PAH source apportionment (CMB)
9
52%
18%
22%
1%7%
Diesel vehicles
Gasoline vehicle
Woodcombustion
Charcoalcombustion
Unexplained
44%
18%
14%
24%
Diesel vehicles
Gasoline vehicle
Wood combustion
Unexplained
10%2%
33%
1%
54%
Diesel vehicles
Gasolinevehicle
Woodcombustion
Charcoalcombustion
Unexplained
19%
1%
18%
3%
59%
Diesel vehicles
Gasoline vehicle
Woodcombustion
Charcoalcombustion
Unexplained
Urban PM2.5 (Wet)
Urban PM2.5 (Dry)
Resident PM2.5 (Wet)
Resident PM2.5 (Dry)
• Biomass combustion (domestic cooking and solid waste burning) contributed >50%
• Lower contribution from mobile source ~20%
• Contributing sources quantified by EI and CMB →mobile source < biomass combustion
PAHs Emission Inventory, 2015
10
2%
24%
28%
26%
20%
Industrial Generator Combusion
Commerical Generator Combustion
Power Plant
Domestic Cooking
Solid Waste Burning
Mobile source
PAHs=
8.6ton/year
• High PM and PAHs levels found in the urban sites as comparedto residential site.
• Higher PM and PAHs levels were in dry season. For PAHs, nosignificant difference between the seasons which may largelycontributed by local sources.
• The main sources of PAHs emission in PNH are mobile sourceand biomass combustion.
• Emission inventory can be used to characterize the sourceprimary pollutants and CMB-a receptor model can used toquantify the contributing to PAHs, but selection of source profileis a challenge.
• Further studies: PMF for PM and PAHs
Conclusions
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