1. 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

2. Item #4 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

3. Item #4 Slide 3 Source: Kim Hooper et al. Cal EPA SF Bay is Global Hot Spot PBDE-47 in Human Tissues 0 5 10 15 20 25 30 35 1981198319851987199019921994199619982000 PBDE-47, ng/g lipids U.S. (San Francisco, adipose) Sweden (adipose) Germany (whole blood) Canada (milk) Finland (milk) Japan (milk) Sweden (milk)

4. Item #4 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

5. Item #4 Slide 5 Bay Inventory

6. Item #4 Slide 6 Mallard Island BDE-47 (ng/L) SSC (mg/L)

7. Item #4 Slide 7 Guadalupe River WY 2005

8. Item #4 Slide 8 Comparison of Tributaries BDE 047 : BDE 209 Guadalupe = 0.2 Coyote = 0.2 Mallard = 1.2

9. Item #4 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 209 Guadalupe = 0.2 Coyote = 0.2 Mallard = 1.2

10. Item #4 Slide 10 * Normalized to SSC * * *

11. Item #4 Slide 11 Summary of Loads

12. Item #4 Slide 12 Mass Budget Model Hindcast – Estimation/Verification of Loads

13. Item #4 Slide 13 Mass Budget Model Forecast – Plausible Future Trajectories

14. Item #4 Slide 14 Mass Budget Model Loss Pathways Under Zero Loads Scenario Outflow and Degradation Are Most Important Loss Pathways

15. Item #4 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