Monochloroacetate — abbreviated MCA — is a structurally similar but genuinely toxic compound that can appear as a contaminant in sodium dichloroacetate. Understanding why MCA matters is critical for anyone researching DCA quality.

MCA (sodium monochloroacetate, CAS 3926-62-3) is the mono-chlorinated version of the molecule. DCA has two chlorine atoms; MCA has one. This seemingly small difference produces dramatically different biological effects. While DCA’s primary action is PDK inhibition, MCA inhibits glycolate oxidase and tricarboxylic acid cycle enzymes — causing cellular energy failure that can damage multiple organ systems at sustained doses.

The problem is that MCA can appear in DCA through incomplete synthesis or degradation, and its presence is completely invisible to standard purity testing. A DCA sample can show 99.5% HPLC purity and still contain dangerous levels of MCA — because the HPLC assay measures the DCA content, not the MCA content separately.

To detect MCA, you need ion chromatography (IC) run as a separate specific test. This test is not included in standard COAs. Most DCA sellers — including many well-established ones — have never tested their product for MCA.

AuraDCA tests every batch for MCA by ion chromatography at Eurofins Vilnius. Our specification is MCA ≤0.05%. Our most recent batch result: None detected.

This article is for informational and educational purposes only. AuraDCA products are intended for research use only.