The overall objective of the TERESA program is to investigate and clarify the impact of the sources and components of fine particulate matter (PM2.5) on human health via a set of realistic animal exposure experiments. The DOE-sponsored portion of the TERESA program, covered by a Cooperative Agreement between DOE and EPRI, is designed to assess the toxicity of coal combustion emissions in the Midwestern and Eastern U.S. by exposing laboratory animals to actual plant emissions that have been “aged” and converted to reaction products in a manner that simulates the conversion experienced by coal power plant plumes in the atmosphere en route to ambient receptor sites. Thus, the primary objective of the DOE-EPRI Cooperative Agreement is to evaluate the potential for adverse health effects from ambient exposure to realistic coal-fired power plant emissions. Secondary objectives of the study include: (1) evaluate the relative toxicity of coal combustion emissions and mobile source emissions, their secondary products, and ambient particles; (2) provide insight into the effects of atmospheric conditions on the formation and toxicity of secondary particles from coal combustion and mobile source emissions through the simulation of multiple atmospheric conditions; (3) provide information on the impact of coal type and pollution control technologies on emissions toxicity; and (4) provide insight into toxicological mechanisms of PM-induced effects, particularly as they relate to susceptible subpopulations.

The TERESA program, managed by EPRI and including the Harvard University School of Public Health (HSPH) as a key participant, was initiated in July 2002 with non-DOE sources of funding. Prior to the start of DOE-EPRI Cooperative Agreement, it is expected that the following work will already have been completed under the TERESA program: (1) construction of the atmospheric reaction chamber and associated equipment; (2) development and validation of the atmospheric simulation methods; (3) outfitting of the mobile animal exposure laboratories; (4) construction and installation of the custom-built emissions collection/dilution/transmission system at a coal-fired power plant in the Upper Midwest; (4) aging of the primary emissions from the Upper Midwest plant; (5) exposure of normal and compromised rats to emissions from the Upper Midwest plant subjected to different simulated atmospheric conditions; (6) physico-chemical characterization of the various Upper Midwest exposure scenario atmospheres; and (7) toxicological evaluation of the Upper Midwest scenario atmospheres.

The DOE-EPRI Cooperative Agreement involves the analysis and interpretation of the field data collected at the Upper Midwest plant, followed by the performance and analysis of similar field experiments at two additional coal-fired power plants in the Eastern U.S., utilizing different coal types and with different plant configurations. Since the Upper Midwest plant uses Powder River Basin (Wyoming) coal (with very low sulfur and low ash), it is anticipated that one of the two additional plants will use low sulfur (<1%) eastern bituminous coal, and the other will use medium-to-high sulfur (>2-3%) eastern bituminous coal. At least one of the plants will have a selective catalytic reduction (SCR) unit for NOx removal, and it is expected that the medium-to-high sulfur unit will utilize a wet or dry scrubber for post-combustion SO₂ removal. EPRI's Generation Sector staff and others with appropriate expertise will participate in the plant selection process.

In each of the field experiments, stack emissions will be introduced into a reaction chamber, where oxidants will be generated to accelerate secondary particle formation. Laboratory rats will be exposed to the primary and aged emissions and evaluated for pulmonary, systemic, and cardiovascular effects. The DOE-EPRI Cooperative Agreement also includes a comparison of the toxicity of coal power plant emissions, mobile source emissions and concentrated ambient particles (CAPs). Animal exposure experiments to evaluate the toxicity of mobile source emissions and CAPs are also part of the overall TERESA program, but will be performed by the project team independently of the DOE-EPRI Cooperative Agreement. At least 3 manuscripts will be submitted to peer-reviewed journals describing the atmospheric simulations and resulting particle formation, the toxicity of coal combustion emissions, and the comparative toxicity analysis.