On April 12, 2006, the EPA issued a direct final rule removing dimethylsulfate (DMS) from the list of chemical substances regulated under the dermal test rule issued in 2004, and removed the requirement that testing be conducted to determine a permeability constant (Kp) for methyl isoamyl ketone (MIAK) and dipropylene glycol methyl ether (DPGME). The agency based its decisions to take these actions on information it received since publication of the final rule. Upon the effective date of the revocation of the Toxic Substances Control Act (TSCA) Section 4 testing requirements for DMS, persons who export or intend to export DMS will no longer be subject to the TSCA Section 12(b) export notification requirements to the extent that they were triggered by the testing requirements being revoked by this action. The rule is effective June 12, 2006, without further notice, unless the EPA receives adverse comment in writing, or a request to present comment orally, on or before May 12, 2006.