[2] Analysis of a sample of a compound called "pangamic acid" which was provided by a co-worker of the Krebses in the 1950s showed only lactose upon further evaluation by nuclear magnetic resonance spectroscopy.
[6] One anecdote noted that the Food and Drug Administration (FDA) has seized lots of "calcium pangamate" sold by General Nutrition Center (GNC), which agreed to stop selling the compound in those bottles after the FDA filed suit to stop sales.
This research was also of limited quality due to being overwhelmingly anecdotal in nature (as opposed to controlled experimentation) and ignoring short and long term safety in human use.
[6] Positive results from mutagenicity analysis via the Ames test of compounds commonly found in preparations labelled "pangamic acid" including diisopropylamine dichloroacetate, diisopropylamine,[7] dichloroacetate,[8] as well as dimethylglycine mixed with sodium nitrite[1] suggests there may be concern for the development of cancer with the use of these substances.
[9] Pangamic acid's distribution in Canada has been prohibited by the then-named Canadian Food and Drug Directorate.