An important analytical artifact was discovered in the article entitled “Pharmacokinetic Analysis of Chloral Hydrate and its Metabolites in B6C3F1 Mice” by R. R. Abbas, C. S. Seckel, J. K. Kidney and J. W. Fisher published in Drug Metabolism and Disposition in 1996 (Vol. 24, No. 12, pp. 1340–1346. In this paper, dichloroacetic acid (DCA) blood concentrations were reported in B6C3F1 mice dosed intravenously with chloral hydrate. In subsequent dosing studies, using new methods for analysis of DCA, no DCA was detected in blood of B6C3F1 mice dosed intravenously with chloral hydrate (<0.05 mg/l). The sample preparation methodology prior to analysis of DCA resulted in an artifactual conversion of trichloroacetic acid (TCA) to DCA. The discovery about the artifactual conversion of TCA to DCA is reported in a recent paper (Journal of Analytical Toxicology, Vol. 12, 1996, pages 236–241) entitled “Conversion of Trichloroacetic Acid to Dichloroacetic Acid in Biological Samples” by M. M. Ketcha, D. K. Stevens, C. T. Bishop, and W. T. Brashear. Jeff Fisher ManTech Environmental Technology, Inc. Armstrong Laboratory Wright-Patterson AFB

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