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Unexpected variations in the purity and structure of commercial detonation nanodiamonds (DNDs) is an ongoing issue. Unfortunately, influences of these variations and how they affect DND behaviors are seldom addressed. This work investigates nominally homologous commercial DNDs sold by a single vendor under the same item number but different lots. Paraffin wax and surfactant were discovered as the major organic contaminants in the DND samples along with metallic impurities. The relative quantities of these contaminants were correlated to discrepancies in the structure and crystallinity of DNDs. The DNDs containing more contaminants possessed thicker shells surrounding the diamond cores; the diamond crystallinity was observed to quickly disappear, on the order of several minutes, when exposed to 200 kV electron beam. On the other hand, those DNDs carrying fewer impurities exhibited a stable diamond structure. The differences in metallic impurities were attributed to variations in the DND purification treatments, and did not appear to affect a morphological change under the electron beam. The present work demonstrates the negative effects of impurities in commercial DNDs on the content and stability of diamond carbons. The results also have implications on possible factors that must be considered when using commercial DNDs for advanced applications. [ABSTRACT FROM AUTHOR]