A mass budget of polybrominated diphenyl ethers in San Francisco Bay, CA

Oram, J. J.; McKee, Lester J .; Werme, C.; Connor, Michael S.; Orós, Daniel; Grace, Richard; Rodigari, François

doi:10.1016/j.envint.2008.04.006

Cited by 37 publications

(23 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unlike models for PCBs or polybrominated diphenyl ethers [6,9], little or no information exists regarding the history of likely changes in global or local emissions and loading rates for methylmercury, nor of changes in other processes. Sensitivity of the model to historical conditions was assessed by adjusting the initial ambient concentrations.…”

Section: Initial Condition Evaluationmentioning

confidence: 96%

“…The model was initially developed by Davis [6] to predict the long-term fate of polychlorinated biphenyls (PCBs) in San Francisco Bay and has been used for developing mass balances for polycyclic aromatic hydrocarbons, organochlorine pesticides, and polybrominated diphenyl ethers [7][8][9]. The current model of San Francisco Bay treats the bay as two well-mixed compartments representing the water column and surface sediments for the region.…”

Section: Regional Mass Balance Modelmentioning

confidence: 99%

“…Bay-specific model parameters were identical to those used in predicting the long-term fate of PCBs in the bay [6], with the addition of a tidal flushing ratio (a ¼ 3.75), a ratio of tidal exchange flow to net freshwater flow in the system. Tidal flushing was not included in the original mass balance model for PCBs but was added in response to review comments [30] and used in more recent applications of the model, such as the polybrominated diphenyl ethers mass balance [9]. Tidal flow rate determined the volume of bay water replaced with water from outside the Golden Gate (the seaward boundary) in each model time step.…”

Section: D)mentioning

confidence: 99%

See 2 more Smart Citations

A regional mass balance of methylmercury in San Francisco Bay, California, USA

Yee¹,

McKee²,

Oram³

2010

Enviro Toxic and Chemistry

Self Cite

View full text Add to dashboard Cite

The San Francisco Bay (California, USA) is a water body listed as impaired because of Hg contamination in sport fish for human consumption, as well as possible effects on resident wildlife. A legacy of Hg mining in local watersheds and Hg used in Au mining in the Sierra Nevada (USA) has contributed to contamination seen in the bay, with additional more recent and ongoing inputs from various sources. Methylmercury is the species of Hg most directly responsible for contamination in biota, so better understanding of its sources, loads, and processes was sought to identify the best means to reduce impacts. A regional scale model of San Francisco Bay was developed to characterize major methylmercury inputs and processes. The model was used to evaluate the potential impact of uncertainties in estimates for methylmercury loading pathways and environmental processes, identify major data gaps, and explore management prospects for reducing methylmercury contamination. External loading pathways considered in the mass balance include methylmercury loads entering via atmospheric deposition to the bay surface, and discharges from the Sacramento/San Joaquin Delta, local watersheds, municipal wastewater, and fringing wetlands. Internal processes considered include exchange between bed and suspended sediments and the water column, in situ production and demethylation, biological uptake, and losses via hydrologic transport to the ocean through the Golden Gate. In situ sediment methylation and demethylation were dominant sources and losses determining ambient steady-state concentrations in the model, with changes in external loads and export causing smaller changes. Better information on methylation and demethylation is thus most critical to improving understanding of methylmercury balances and management.

show abstract

Section: Initial Condition Evaluationmentioning

confidence: 96%

Section: Regional Mass Balance Modelmentioning

confidence: 99%

Section: D)mentioning

confidence: 99%

See 1 more Smart Citation

A regional mass balance of methylmercury in San Francisco Bay, California, USA

Yee¹,

McKee²,

Oram³

2010

Enviro Toxic and Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the Great Lakes ecosystem in the United States, atmospheric deposition is a major source of PBDEs [10], and although water concentrations are relatively low due to the hydrophobic nature of PBDEs (54.9 pg BDE-47/L in San Francisco Bay watershed [no Great Lakes data available] [11]), organic matter contains greater concentrations and creates the basis for potential biomagnification (tri-through hepta-BDEs in surficial sediments are 2.8 ng/g dry wt) [12]. Concentrations of PBDEs in Great Lakes food webs range from 1.4 ng/g in zooplankton to >1,000 ng/g tissue in top-predator fishes [1,13,14].…”

Section: Introductionmentioning

confidence: 99%

Chronic, dietary polybrominated diphenyl ether exposure affects survival, growth, and development of Rana pipiens tadpoles

Coyle

Karasov

2009

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Levels of polybrominated diphenyl ethers (PBDEs) in the environment have been increasing rapidly over the past two decades; however, the toxicology of these compounds to aquatic organisms is poorly understood. Because amphibians play a role in both aquatic and terrestrial food webs, and are currently undergoing worldwide population declines, it is of interest to determine how PBDEs may affect amphibian health. This is the first study that reports chronic, dietary effects of environmentally relevant levels (7-277 ng/g wet food) of PBDEs in amphibians throughout larval development. Beginning at the free-swimming stage (Gosner Stage [GS] 25), Rana pipiens tadpoles were orally exposed to a technical pentabromodiphenyl ether mixture (DE-71) through metamorphic climax (GS 42). On exposure day 43, a subset of tadpoles was removed for body residue analysis. Sum PBDEs in whole-body tissue correlated linearly to dietary concentrations with BDE-99 represented as the highest contributing congener in both diet and tissue. Survival among all treatments compared to the control was decreased by DE-71 exposure. Further, growth and development were delayed in all but the highest treatment, perhaps indicating greater PBDE tolerance among those individuals that survived the highest treatment. Time to metamorphic climax was delayed, on average, 22 to 36 d in DE-71-treated tadpoles compared to control tadpoles. Additionally, size at metamorphosis was smaller in the highest treatment, suggesting that individuals that survived and metamorphosed similarly to the controls did so with a trade-off in size. At environmentally relevant levels, PBDEs induced mortality as well as sublethal effects on developing tadpoles through dietary exposure.

show abstract

“…Hence, the influence of typhoons on the long-term remobilization of PCDD/Fs supports the hypothesis that relevant events have the possibility to reactivate pollutants that have been accumulated in the past. Oram et al (2008) has indicated that extensive measurement of POPs in water of shore-side, freshwater, sediment, ambient air, wastewater outflow and sludge can be integrated via a model of mass budget providing a synthetic observation of these emerging pollutants. The Tsengwen Reservoir (TWR) is the most important reservoir in southern Taiwan; it is a multifunction reservoir the primary purpose of which is the supply of water to southern Taiwan.…”

Section: Introductionmentioning

confidence: 99%

Sources and Deposition Fluxes of PCDD/Fs in the Largest Reservoir System in Taiwan before and after Typhoon Morakot

Hsien

Luo

Kao

et al. 2015

Aerosol Air Qual. Res.

View full text Add to dashboard Cite

The Tsengwen Reservoir (TWR) is positioned at 23°16′N, 120°34′E and is the largest reservoir in Taiwan. During 2009 to 2010, deposition flux of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) in atmosphere, water bodies and sediments were measured in the TWR area for this study. The monthly ambient air PCDD/F deposition in the surrounding area of the TWR was found to range from 0.206 to 2.43 pg I-TEQ/m 2 /day. In addition, the PCDD/F levels (11 to 12 fg I-TEQ/L) in the shell water (water depth: 0.5 m) were found to be uniform and well mixed within the upstream, central and lower reaches of the TWR. The PCDD/F input flux into the reservoir was investigated in two sediment cores sampled at the TWR. The year dating within the sediment cores at different depths was projected from the sedimentation rate (> 17 cm/y) and calculated by (January, 2010). During the severe typhoon periods, the PCDD/F input contributed by the enhanced catchment landslides dramatically increased to 99%.

show abstract

A mass budget of polybrominated diphenyl ethers in San Francisco Bay, CA

Cited by 37 publications

References 46 publications

A regional mass balance of methylmercury in San Francisco Bay, California, USA

A regional mass balance of methylmercury in San Francisco Bay, California, USA

Chronic, dietary polybrominated diphenyl ether exposure affects survival, growth, and development of Rana pipiens tadpoles

Sources and Deposition Fluxes of PCDD/Fs in the Largest Reservoir System in Taiwan before and after Typhoon Morakot

Contact Info

Product

Resources

About