The objective of this contract is to determine the potential toxicity/carcinogenicity of three chemicals via the inhalation route of exposure to F344 rats and B6C3F1 mice. The project involves prechronic and chronic studies of divinylbenzene, stoddard solvent (type II-C) and optionally, stoddard solvent (type I-A). The 14-day studies involve the treatment of 5 animals per sex/species at 5 exposure concentrations plus controls. The 90-day studies involve the treatment of 10 animals per sex/species at 5 exposure concentrations plus controls. Special studies in the subchronic study include hematology, clinical chemistries, SMVCE and micronuclei (mice). The 2-year studies involve the treatment of 50 animals per sex/species at 3 exposure concentrations plus controls.