Download Climate Change and fate of persistent organic pollutants (POPs)

Climate Change and fate of
persistent organic pollutants (POPs)
Gan Zhang
Guangzhou Institute of Geochemistry
The Chinese Academy of Sciences
september [email protected]
Persistent organic pollutants (POPs)
• toxic chemicals, persistent in the environment
• long-range transport via air, ocean currents etc
• mostly hydrophobic, tend to accumulate in biota
• Stockholm Convention: global POP source reduction
Dirty Dozen!!
Aldrin
Chlordane
Endrin
PCDD
Heptachlor
HCB
Toxaphene
PCDF
Mirex
DDT
Diendrin
PCB
3 categories:
HCH
PAH
PBDE
• Pesticides
• Industrial products
• Unwanted by-products
Temperaturedriven global
distillation
and
transport?
(UNEP, 2004)
(Wania and Mackay, 1993)
More POPs will
transport to
cryogenic
environment ?
Potential of glacier retreat to release POPs?
- lessons learned from the Arctic
AMAP, 2003
What if we go to lakes in the Tibetan plateau?
E80o
E90o
E100o
N40o
N40o
Mt
.T
Wudaoliang
®
Star Sea
an
gg
ula
Co Ngoin
Hi
ma
Yamzho Yumco Lhasa
®
lay
a
N30o
N30o
Namjagbarwa
®
I
®
75
Yamzho Yumco (羊卓雍错）
Sediment core
Reference site
Warm & humid air flow
0
75
II
150 mile
Co Ngoin (错鄂）
Num Co (纳木错）
Beautiful dating results !!
Ln(210Pb-ex)
1
0
10
Ln(210Pb-ex)
1
1
10
Ln(210Pb-ex)
0
0
3
Depth/cm
3
3
6
6
9
6
9
12
15
a
y = -9.9612Ln(x) + 20.967
2
R = 0.9798
9
b
y = -5.8659Ln(x) + 7.4599
2
R = 0.9715
12
c
y = -14.919Ln(x) + 15.235
2
R = 0.9832
Yamzho Yumco (羊卓雍错）
Co Ngoin (错鄂）
Star Sea (星星海）
0.31 cm/a
0.36 cm/a
0.46 cm/a
10
DDTs concs ‘rebound’!
DDT concs increase after 1987
at Yamzho Yumco, after 1998
at Co Ngoin, after 1991 at Star
Sea.
DDE/DDTs ratios increase in
the meantime, indicating
recycled ‘weathered’ DDT.
What happened in recent years in the plateau?
-4.0
Wudaoliang
Global warming

Increasing evaporation

Glacier retreat

Melting of permafrost
-5.0
T/oC
Increasing precipitation
-6.0
-7.0
1950
1960
1970
1980
1990
2000
1970
1980
1990
2000
2.0
Lhasa
1.0
T/oC

0.0
-1.0
-2.0
1950
1960
Glaciers in the plateau
WWF, 2005
Glaciers retreated faster after in the 1990s than before.
WWF, 2005
Global warming enhanced relocation of DDTs?
DDT trapped in snow pack and ice
may be released become
available to be transported;
Snow/ice water, intensified
precipitation may also helps to
flush and transport recycled DDT
from soil to the lake basins.
WWF, 2005
Yangtze River mud zone: 4 cores
Coastal, YRE sourced
- N4, N6: Yangtze River estuary
- S3, S5: Down stream mud
zone off Zhejiang province
Lin et al., 2009
Coastal: average sedimentation rates from 1 to 3.4 cm/a, higher in
the YRD than mud zone off Zhejiang province
DDTs records in YRE (top) and mud zones off Zhejiang province
• Sharp rebound and
peaked at the
layers of the 1990s
• Peaks in late 1998
may be related to
the severe
watershed flood
record in 1998
Lin et al., 2009
‘Old’/recycled DDT input observed at sites N6 and S5
Strong land transform in the Taihu Lake region
• Cultivated land loss coincided GDP sharp increase
• 1992-1995 peak corresponded with DDT rebound well, suggesting a
DDT relocation by enhanced soil-runoff.
50000
45000
40000
35000
30000
25000 Cultivated Land loss Area
20000
15000
10000
5000
0
1975
1980
1985
1990
GDP
1995
2000
2005
(data from official statistic books)
Coupling between C cycle the fate of SVPPs?
sum tri-PCB
sum tetra-PCB
2.5
2.0
1.5
1.0
0.5
log conc (pg/g dw )
3.0
0.0
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
20
40
60
80
100
0
20
% organic matter
sum hexa-PCB
2.0
1.0
0.0
40
60
% organic matter
80
100
0
20
80
100
40
60
80
100
80
100
% organic matter
sum octa-PCB
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
3.5
log conc (pg/g dw )
log conc (pg/g dw )
3.0
20
60
sum hepta-PCB
4.0
0
40
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
% organic matter
5.0
log conc (pg/g dw )
sum penta-PCB
3.5
log conc (pg/g dw )
log conc (pg/g dw )
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
20
40
60
% organic matter
80
100
0
20
40
60
% organic matter
Meyer et al. 2003
Relationship between soil concentration and OM content
Soil with high total organic carbon
TOC
Dalla-Valle et al., 2004, 2005
Coupling between C cycle the fate of POPs
Air
SVPPs
SVPPs
Which is the ”exchangeable” fraction of SVPPs?
SOM tourn-over
Is the system a net sink for these pollutants?
Under which conditions this system
re-emit pollutants?
Soil
Luca Nizzetto
1 December
2009
25
Nizzetto et al., EST, 2010
Mechanisms of the air-surface exchange
of organic pollutants and mercury in a
Chinese subtropical forest
Research Council of Norway
Chinese Accademy of Science
Norwegian Institute for Water Research
L. Nizzetto, K. Borgå, T. Larssen,
G. Zhang, X. Feng, K.C. Jones
The players:
NIVA Norwegian Institute for Water Research –
Oslo
State Key Lab. for Organic Geochemistry (CAS) –
Guanzhou
State Key Lab. for Environmental Geochemistry
(CAS) - Guiyang
Lancaster Environment Centre, Lancaster, United
Kingdom
The numbers:
- 2 outstanding European research institutes
- 2 outstanding Chinese research institutes
- 6 senior researchers, 2 PhD students.
- 3 million Norwegian Krowns (3,6 million
RMB) from Norwegian Research Council
- About 1,5 million (1,8 million RMB) as
counter part from the involved institutes
The place:
Dinghushan Biosphere
Reserve - Subtropical forest
The methods:
Top soil layer
Organic matter
Deposition of:
- Organic matter
- Rain
- ”Native” pollutants
+ Environmental and
climatic conditions
PUF
Sorbant for
pollutants
The ”big picture”
Effect of Climate change on
the global fate and exposure to
persistent pollutants
Chinese ecoregions:
From tropical to
boreal ecosystems
Thank you for your attention！