Transport of Perfluorochemicals to Surface and Subsurface Soils

Minnesota Department of Transportatio

Application of a comprehensive extraction technique for the determination of poly- and perfluoroalkyl substances (PFASs) in Great Lakes Region sediments.

A comprehensive method to extract perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl carboxylic acids (PFCAs), polyfluoroalkyl phosphoric acid diesters (diPAPs), perfluoroalkyl phosphinic acids (PFPiAs) and perfluoroalkyl phosphonic acids (PFPAs) from sediment and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and applied to sediment cores from three small isolated lakes (Plastic Lake, Lake 442, Lake Tettegouche) and Lake Ontario in the Great Lakes Region. Recoveries of the target compounds using the optimized acetonitrile/sodium hydroxide extraction ranged from 73% to 120%. The greatest concentrations of per- and polyfluorinated alkyl substances (PFASs) were recorded in sediment from Lake Ontario (ΣPFASs 13.1 ng/g), where perfluorooctane sulfonic acid (PFOS) contributed over 80% of the total. Concentrations in Lake Ontario were approximately 1-2 orders of magnitude greater than the more remote lakes subject to primarily atmospheric inputs. Whilst the PFAS contribution in Lake Ontario was dominated by PFOS, the more remote lakes contained sediment with higher proportions of PFCAs. Trace amounts of emerging PFASs (diPAPs and PFPiAs) were found in very recent surface Lake Ontario and remote lake sediments

Enhanced Sorption as a Means to Sequester PFAS

Matt Simcik - Associate Professor, Division of Environmental Health Sciences, University of Minnesota. Dr. Simcik, along with his colleagues, have developed an in situ remediation method for PFAS contaminated groundwater. It involves the addition of cationic polymer coagulants and in some cases powdered activated carbon. They also have plans to develop this method for surface water, wastewater treatment, landfill leachate as well as increasing the efficiency of drinking water treatment. Dr. Simcik presented results of our work on developing the method and plans for field implementation.Ope

Enhanced Removal of Hydrophobic Organic Contaminants by Setting Sediments in Western Lake Superior.

Abstract not availableJRC.H-Institute for environment and sustainability (Ispra

The Impact of Urban Areas on the Deposition of Air toxics to Adjacent Surface Waters: A Mass Budget of PCBs in Lake Michigan in 1994

The impact of urban air toxics on the proximate water bodies was investigated as part of the AEOLOS Project ( Atmospheric Exchange Over Lakes and Oceans). The hypothesis of this project was that emissions of hazardous air pollutants into the coastal urban atmosphere increased atmospheric depositional fluxes to proximate Great Waters. Areas of major field and modeling campaigns were located in southern Lake Michigan near Chicago, IL and northern Chesapeake Bay near Baltimore. The impact on Lake Michigan of PCB emissions from the urban area of Chicago was evaluated through field experiments to determine atmospheric concentrations, surface water concentrations, wet and dry deposition and bi-directional gas exchange. These values were used to construct a PCB mass budget for the Lake Michigan ecosystem, which includes the urban influence. PCB emissions in the Chicago atmosphere lead to dramatically increased atmospheric concentrations of PCBs off shore and significantly increased wet, dry particle and air-water exchange fluxes in southern Lake Michigan compared to the regional signal. High PCB concentrations occur over the lake only when the wind is from the direction of the urban/industrial complex inclusive of the shoreline from Gary, IN to Evanston, IL toward the lake. Although atmospheric loading of PCBs was much higher in the southern basin of Lake Michigan, water column concentrations have significantly decreased from 1980 to 1994 through the rapid uptake by settling particles, and have continued to decrease at a rate of 0.17 yr(-1). In contrast to earlier PCB mass budgets that missed significant inputs, outputs and/or process terms, inclusion of the urban-influenced air-water exchange processes and a re-evaluation of new lake data effectively closed the PCB budget for Lake Michigan. Atmospheric exchange processes dominated the whole lake budget. The Chicago area, with high industrial density, emits large quantities of hazardous organic pollutants and has important impacts on the down wind coastal atmosphere and proximate surface waters

Perfluoroalkyl Substances Increase the Membrane Permeability and Quorum Sensing Response in <i>Aliivibrio fischeri</i>

Perfluoroalkyl substances (PFAS) are used in a variety of products and are ubiquitous in the environment. They have been found to associate with eukaryotic cell membranes and alter membrane properties. Bacteria are exposed to elevated concentrations of PFAS in some environments; nevertheless, the effect of PFAS exposure on microbial membranes has not yet been studied. Some quorum sensing pathways require the passive diffusion of signaling molecules through cell membranes. Quorum sensing initiates a variety of bacterial processes, such as biofilm formation and antibiotic production. If PFAS exposure increased the microbial quorum sensing response, these processes could be initiated at lower population densities, with wide-ranging ramifications for PFAS-impacted environments. This study examined the effect of perfluorinated alkyl sulfonates and carboxylates on quorum sensing in a model bacterium, <i>Aliivibrio fischeri</i>. Results showed that cultures exposed to PFAS were brighter after they received the signaling molecule. The observed increase in luminescence was dose-dependent and increased with the fluorinated carbon number. Specifically, perfluorooctanesulfonate increased luminescence at levels as low as 10 μg/L. PFAS-exposed bacteria were also more permeable to a semi-membrane permeable dye. Therefore, it is likely that increased permeability was, at least in part, the cause of increased luminescence