| Abstract: | It is the major intent of this report to examine the animal inhalation facilities at the EPA Health Effects Research Laboratory in Cincinnati, Ohio, associated with the exposure to the exhaust of diesel-powered equipment. The facility serves as a center for toxicologic evaluation, in relevant animal models, of potentially hazardous environmental pollutants from diesel engine exhaust. Briefly, the entire engine exhaust is mixed with filtered and conditioned air in a dilution tube. That diluted exhaust enters a large volume mixing chamber and a portion passes through dynamic flow irradiation chambers (to simulate sunlight) and is then conducted to animal exposure chambers. The system provides nonirradiated exhaust in the same concentration (directly from the mixing chamber) and also filtered, conditioned ambient air for control animal exposure. The major physical components of the diesel emission system include: air purifiers, animal exposure chambers, engine-dynamometers, irradiation chambers, monitoring instrumentation and data acquisition systems. |
