item #4 slide 1 a mass budget of polybrominated diphenyl ethers in san francisco bay, ca john j....
TRANSCRIPT
Item #4
Slide 1
A Mass Budget of Polybrominated Diphenyl Ethers in San Francisco
Bay, CA
John J. Oram, Lester J. McKee, Christine E. Werme, Mike S. Connor,
and Daniel R. Oros
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Slide 2
Introduction• Flame retardants in plastics and textiles• Ubiquitous environmental pollutants• Only recently included in environmental assessments• Appear to be exponentially increasing throughout the
world• Transport pathways not fully understood
– Thought to be similar to PCBS, OC Pesticides.
• This paper is first of its kind for– PBDEs in urban rivers– PBDE mass budget for urbanized estuary
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Slide 3
Source: Kim Hooper et al. Cal EPA
SF Bay is Global Hot SpotPBDE-47 in Human Tissues
0
5
10
15
20
25
30
35
1981 1983 1985 1987 1990 1992 1994 1996 1998 2000
PB
DE
-47,
ng/
g li
pid
s
U.S. (San Francisco, adipose)Sweden (adipose)Germany (whole blood)Canada (milk)Finland (milk)Japan (milk)Sweden (milk)
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Slide 4
Pieces of the Mass Budget
• Bay water and sediment– Inventory
• Unfiltered water at Mallard Island, Coyote Creek, Guadalupe River, and Zone 4 Line A– Tributary loads
• Effluent and sludge from 3 tertiary plants– Wastewater loads
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Slide 5
Bay Inventory
Mean Lower 95% CI Upper 95% CIBDE 047 31.44 28.89 33.99BDE 209 97.98 54.61 141.37
Total Mass in Water and Sediment (kg)
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Slide 6
Mallard IslandB
DE
-47
(ng/
L)
SSC (mg/L)
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Slide 7
Guadalupe River
WY 2005
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Slide 8
Comparison of Tributaries
Min Max FWMC Min Max FWMC Min Max FWMCBDE 047 1.69 26.50 7.99 1.25 3.53 2.63 0.17 0.22 0.18BDE 209 8.50 115.00 43.30 7.29 22.40 14.66 0.12 0.26 0.15BDE 047 0.56 18.40 5.29 0.13 0.35 0.14BDE 209 1.74 119.00 32.32
WY 2006
Guadalupe Coyote MallardCongener
WY 2005
BDE 047 : BDE 209Guadalupe = 0.2Coyote = 0.2Mallard = 1.2
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Slide 9
• Why more BDE 047 @ Mallard?– Two hypothesis are emerging:
1. Atmospheric deposition to Central Valley• 47 more volatile than 209 = greater potential for
long-range atmospheric transport & deposition
2. Dissolved loads greater• 47 more soluble than 209; Combined with long
residence time of Delta (weeks to months) may make dissolved loads more important
BDE 047 : BDE 209Guadalupe = 0.2Coyote = 0.2Mallard = 1.2
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Slide 10
Location PBDEs - BDE 209 BDE 047 BDE 209
Canada (Columbia River)1 3.8 - 90.9
China (Pearl River Delta)2 0.04 - 94.7 0.4 - 7340
China (Yangtze River Delta)8 ND - 0.55 0.16 - 94.6
China3 0.1 - 5.5
Denmark3 0.53 3.67 - 21.5
Japan3 8 - 352 <25 - 11600
Korea3 1.1 - 33.8
Kuwait7 0.08 - 3.8
Netherlands3 0.6 - 17.6 4 - 510
Portugal 0.5 - 203 0.03 - 9.9112
Spain 0.4 - 34.13 0.1 - 0.29 2.1 - 1323
Sweden 8 - 503 <1.611 68 - 71003
UK 1.3 - 1270.83 <0.3 - 36810 0.6 - 31903
USA <0.5 - 63.63,4 <0.5 - 52.313 29 - 15483,5
This Study
Coyote Creek, CA6 19.3 - 128.8 4.6 - 31.9 17.1 - 202.9
Guadalupe River, CA6 29.1 - 1248.4 7.4 - 219.9 23.3 - 1997.6
Mallard Island, CA6 5.5 - 9.6 2.4 - 3.7 2.2 - 6.5
SF Bay, CA ND - 21214 0.05 - 3.84 0.1 - 12.6
PBDE concentrations (ng/g) in San Francisco river and bay sediments compared to world river and coastal sediments.
* Normalized to SSC
***
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Slide 11
Summary of Loads
Source PBDEs BDE 047 BDE 209Sacramento-San Joaquin Delta 13 3 3Local Tributaries 33 3 17Municipal Wastwater 12 - 58 4 - 21 1 - 3Atmospheric Deposition 1 - 2 ~1 ~1Total 59 - 106 11 - 28 22 - 24
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Slide 12
Mass Budget ModelHindcast – Estimation/Verification of Loads
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Slide 13
Mass Budget ModelForecast – Plausible Future Trajectories
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Slide 14
Mass Budget ModelLoss Pathways Under Zero Loads Scenario
Outflow and Degradation Are Most Important Loss Pathways
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Slide 15
Conclusions
• SF Bay is global hot spot
• Loads dominated by local tributaries (stormwater runoff) and wastewater
• Model provides useful framework for integrating / synthesizing information
• SF Bay at critical juncture in terms of recovery