The organizations that remediate Superfund sites face the challenge of how to measure success; i.e., how to assess the changes in the bioavailability of contaminants. They need quantitative tools that can characterize contaminants and predict their risk to local organisms and humans. Non-chemical factors such as ultra-violet radiation can transform the parent compounds into unmonitored chemicals that can change the toxicity of waters and sediments. To address this issue, we have developed passive sampling devices (PSDs) that can sequester thousands of bioavailable chemicals. These devices can help regulatory agencies to evaluate new remediation technologies that may either produce or release previously unmonitored chemicals. We will develop PSD-bioaccumulation models that can predict chemical load in aquatic tissues with useful accuracy on the basis of measured PSD extracts. The ability to predict aquatic tissues from PSD extracts will enable Superfund managers and public health officials to collect data with better temporal and spatial resolution.
- Collect mixtures of chemicals at Superfund sites with complementary PSD materials and identify the components of those mixtures that induce biological responses.
- Apply additional stressors to PSD extracts and characterize the chemical and biological effects.
- Develop PSD-bioaccumulation models that can predict chemical load in aquatic tissues with useful accuracy on the basis of measured PSD extracts.
Concentrations from PSDs may be used in air and water exposure cumulative risk assessments as well as substituted for fish/shellfish tissue concentrations in existing health risk models. Adding passive sampler data to assess cumulative exposure and to health risk models increases spatial and temporal precision, improves risk estimates based on environmental characterization of exposure, reduces animal collection, and reduces costs.
- Fractionated PSD extracts and have tested for toxicity in each fraction within the zebrafish model.
- Integrated our bioavailable extract into laboratory-based stressors experiments.
- Successfully used passive sampler extracts from Superfund sites to predict resident crayfish tissue concentrations for PAHs.
- Evaluated passive sampling devices (PSDs) as surrogates for biological organisms with respect to bioavailable PAHs.
- Deployed PSDs at numerous NPL sites in the country and characterized hundreds of PAHs and PAH derivatives.
- Established the world’s largest repository of PAHs and PAH derivatives (alkyl, oxy-, hydroxy-, nitro-).
- Deployed the first PSDs in the Gulf of Mexico after the Deep Horizon Gulf Oil spill and collected the only data set with an accurate baseline before the oil arrived on shore.
- Organized an SRP webinar to disseminate information on the utility of PSDs.
- Co-organized an event with Community Engagement Core and the Louisiana State University Superfund Research Program: Response, Recovery, and Resilience to Oil Spills and Environmental Disasters: Engaging Experts and Communities - A Symposium and Workshop for Community Stakeholders, Researchers and Policymakers, January 2013 in Baton Rouge, LA.