Food Safety and Environmental Stewardship Program

Polycyclic aromatic hydrocarbons (PAHs) are present in crude oil and may persist in the environment even after visible evidence is gone. Volatilization of crude oil can be one route of exposure for PAHs.  Exposures of PAHs from crude oil spills typically occurs concurrent with the spill or prior to significant weathering of the oil. Acute chemical spills generally initiate a rapid clean up response; however, there is often a significant exposure period prior to elaborate air monitoring equipment setup.  Because PSDs do not require elaborate equipment or electricity, we were able to sample within days of the Deepwater Horizon Oil Spill. We deployed passive sampling devices (PSDs) for air sampling prior to, during and after shoreline oiling. Study locations included sites in Louisiana, Mississippi, Alabama and Florida. PSDs mimic the chemical uptake of biomembranes by exploiting the fugacities of vapor phase compounds in the atmosphere. Chemical data from PSD extracts can be employed to assess potential exposure, transport, fate and sourcing of emerging and legacy contaminants in the atmosphere. 

Forty two samples were collected over a 15 month period beginning in May 2010; passive sampling devices were used to monitor the bioavailable concentration of PAHs in air. Prior to shoreline oiling, baseline data was obtained at all the study sites, allowing for direct before and after comparisons of PAH air contamination due to oiling. Samples were analyzed using a method composed of 33 emerging and legacy PAHs. As many as 18 PAHs were quantified in some air PSD extracts. Flouranthene, pyrene and phenanthrene were the largest contributors to the total vapor phase PAH concentration at our sampling sites. PSDs were also screened for an additional 1,200 contaminants of concern. Analysis of PSDs with this screening method resulted in positive identification of oxygen, sulfanate and nitrogen substituted PAHs, pesticides, and compounds used in industry such as musks and flame retardants. Our study demonstrates the utility of air PSDs to respond to acute chemical spills and collect chemical data sets on a wide range of contaminants in a more rapid fashion than traditional air monitoring technologies. During this study OSU’s Superfund Research Program Research Translation and Community Engagement Cores developed resources including workshops, brochures, and web-based information available to the communities impacted by the spill.