EPA is revoking specific tolerances and tolerance exemptions for residues of the bird repellent 4-aminopyridine, fungicides ammonia and vinclozolin, and insecticides chloropicrin, diazinon, dihydro-5- heptyl-2(3H)-furanone, and dihydro-5-pentyl-2(3H)-furanone. EPA canceled food use registrations or deleted food uses from registrations following requests for voluntary cancellation or use deletion by the registrants, or non-payment of registration maintenance fees. The regulatory actions in this document contribute toward the Agency's tolerance reassessment requirements of the Federal Food, Drug, and Cosmetic Act (FFDCA) section 408(q), as amended by the Food Quality Protection Act (FQPA) of 1996. By law, EPA is required by August 2006 to reassess the tolerances in existence on August 2, 1996. The regulatory actions in this document pertain to the revocation of 39 tolerances and tolerance exemptions of which 33 count as tolerance reassessments toward the August, 2006 review deadline.