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Polybrominated Diphenyl Ether (PBDE) Flame Retardants in San Francisco Bay Daniel R. Oros, Ph.D. San Francisco Estuary Institute. PBDEs are HOT contaminants!. PBDEs are HOT contaminants! P ersistent: long lived in the environment. PBDEs are HOT contaminants!
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Polybrominated Diphenyl Ether (PBDE) Flame Retardants in San Francisco Bay Daniel R. Oros, Ph.D. San Francisco Estuary Institute
PBDEs are HOT contaminants! • Persistent: long lived in the environment
PBDEs are HOT contaminants! • Persistent: long lived in the environment • Bioaccumulative: transport through food webs
PBDEs are HOT contaminants! • Persistent: long lived in the environment • Bioaccumulative: transport through food webs • Dispersed: world-wide contamination in humans, animals, our food sources and environment
PBDEs are HOT contaminants! • Persistent: long lived in the environment • Bioaccumulative: transport through food webs • Dispersed: world-wide contamination in humans, animals, our food sources and environment • Endocrine disruptors: target the thyroid
PBDE Commercial Mixtures and Major Congeners Penta BDE-99 BDE-47 BDE-100 BDE-153 BDE-154 Deca Octa BDE-183 BDE-209
PBDEs Banned in California • Ban on Penta and Octa mixtures, but not Deca, will be in effect on June 1, 2006 • The ban might not be very effective at decreasing environmental PBDE concentrations • North America use of PBDEs: Deca (75%), • Penta (21%) and Octa (4%) of total mass • Deca degrades to lower molecular weight PBDE congeners
Distribution of PBDEs in SF Bay Water 2002 PBDEs range 3-513 pg/L Source: RMP
Distribution of PBDEs in SF Bay Sediments 2002 PBDEs range 0.2-212 ng/g dry wt Source: RMP
Distributions of PBDEs in SF Bay Bivalves 2002 PBDEs range (dry wt) Mussels 13-47 ng/g Oysters 9-64 ng/g Clams 85-106 ng/g Source: RMP
Distributions of PBDEs in SF Bay Bivalves 2001-2003 Source: RMP
Distributions of PBDEs in SF Bay Fish 1997 and 2002 Source: EWG, 2003
Distributions of PBDEs in SF Bay Tern Eggs. Forester’s tern eggs showed the highest ever reported PBDE levels in wildlife = 63 ppm Source: She et al., 2004
Current work in the Bay • PBDE Conceptual Model and Impairment Assessment funded by RMP and CEP • Identify PBDE Sources • Estimate PBDE Loading • Assess Extent of Bay Impairment from PBDEs
Major Sources of PBDEs to the Environment • Wastewater effluents • Sludge disposal • Volatilization from commercial products • Burning of disposed commercial products • Other Suspected Sources • Atmospheric deposition (e.g., autofluff piles) • Tributary inflow (stormwater runoff)
Like PCBs, the PBDEs in Guadalupe River are strongly associated with suspended sediments Source: RMP
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 9-10 Br Atoms 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 7-10 Br Atoms 9-10 Br Atoms 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). BDE-209 is not detected at 30 min 7-9 Br Atoms 7-10 Br Atoms 9-10 Br Atoms 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 5-8 Br Atoms BDE-209 is not detected at 30 min 7-9 Br Atoms 7-10 Br Atoms 9-10 Br Atoms 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 4-7 Br Atoms 5-8 Br Atoms BDE-209 is not detected at 30 min 7-9 Br Atoms 7-10 Br Atoms 9-10 Br Atoms 10 Br Atoms (BDE-209)
Sunlight degrades BDE-209 to lower molecular weight congeners (Source: Bezares-Cruz et al., 2004). 3-7 Br Atoms 4-7 Br Atoms 5-8 Br Atoms BDE-209 is not detected at 30 min 7-9 Br Atoms 7-10 Br Atoms 9-10 Br Atoms 10 Br Atoms (BDE-209)
Closing • The Bay Area appears to be a “Hot Spot” for PBDEs • The CA ban on Penta and Octa, but not Deca, might not result in an immediate and significant decrease in environmental PBDE levels • Water and sediment quality criteria have not yet been developed for PBDEs, but they are coming.
Acknowledgements • RMP • AXYS Analytical Services Ltd • East Bay Municipal Utility District • CA Dept of Fish and Game • SFEI