Comment submitted by C. Collins

The Environmental Protection Agency (EPA) has proposed a chemical testing rule that would require manufacturers and processors to test four chemicals: chloroethane, hydrogen cyanide, sodium cyanide, and methylene chloride. These chemicals are commonly found at toxic-waste sites. The testing has been proposed at the request of the Agency for Toxic Substances and Disease Registry (ATSDR) as part of its responsibilities under the Superfund Act. All the chemicals slated for additional testing are widely used and have already been studied extensively. Chloroethane has been used as an anesthetic for decades, and hydrogen cyanide is so lethal that it was used in gas chamber executions. Although the EPA and ATSDR claim that they have avoided the "excessive use" of animal testing, the tests required under the proposed rule would cause the deaths of as many as 18,000 animals! Many of these tests will cause intense suffering. For example, rats will be forced to inhale concentrations of cyanide gas that are already known to cause violent death following convulsions, bleeding from the lungs, and asphyxiation. The EPA as well as chemical manufacturers and processors need to live up to their commitments to replace, reduce, and refine the use of animals in chemical testing. I respectfully request that the EPA do the following: ? Reevaluate the data needs identified by ATSDR, some of which are nonsensical. For example, testing in which animals are force-fed chloroethane through a tube inserted into their stomachs is required, even though chloroethane is a gas at room temperature. ATSDR has admitted that accidental oral exposure to chloroethane in doses large enough to result in death is highly unlikely, and extensive inhalation data already exist. Why must animals die to generate more useless data? ? Use physiologically based pharmacokinetic (PBPK) models to fill ATSDR's data needs by extrapolating from existing data. These sophisticated mathematical models already exist for chloroethane and methylene chloride. This approach would save money and many animal lives! ? Accept test protocols that reduce the number of animals used by eliminating duplication and combining multiple tests. Using internationally accepted combination tests can drastically reduce the number of animals killed. Thank you for your time and consideration in reviewing this issue. Please feel free to contact me if there are any further questions or clarification. Sincerely, Carol L. Collins