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

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.
Recent bans on Penta- and Octa- mixtures
BDE 47 and 209 chosen for this paper due to overlap in SF Bay regional monitoring.
This paper is first of its kind for
PBDEs in urban rivers
PBDE mass budget for urbanized estuary

3. SF Bay Area is Global Hot Spot
PBDE-47 in Human Tissues 35
U.S. (San Francisco, adipose) 30
Sweden (adipose)
Germany (whole blood) 25
Canada (milk)
Finland (milk) 20
PBDE-47, ng/g lipids
Japan (milk) 15
Sweden (milk) 10 5
1981
1983
1985
1987
1990
1992
1994
1996
1998
2000
Source: Kim Hooper et al. Cal EPA

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

5. Bay Inventory

6. Guadalupe River
WY 2005

7. Mallard Island
BDE-47 (ng/L)
SSC (mg/L)

8. Comparison of Tributaries
(ng/L)
BDE 047 : BDE 209
Guadalupe = 0.2
Coyote = 0.2
Mallard = 1.2

9. Why more BDE 047 @ Mallard? Two hypothesis are emerging:
Atmospheric depostion to Central Valley (EXTERNAL)
47 more volatile than 209 = greater potential for long-range atmos transport & depostion
Dissolved loads greater (INTERNAL)
47 more soluble than 209; Combined with long residence time of Delta (weeks to months) may make dissolved loads more important
BDE 047 : BDE 209
Guadalupe = 0.2
Coyote = 0.2
Mallard = 1.2

10. * * *
* Normalized to SSC

11. Summary of Loads (Kg)

12. Mass Budget Model Hindcast – Estimation/Verification of Loads

13. Mass Budget Model Forecast – Plausible Future Trajectories

14. Mass Budget Model Loss Pathways Under Zero Loads Scenario
Outflow and Degradation Are Most Important Loss Pathways

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