By Darryl A. LeBlanc, PhD, Principal Scientist, Analytical Services, Cambrex
Impurities in drug products can arise at various time points during the manufacturing process or during storage. Without swift identification to assess potential risk, they can stall critical clinical timelines or cause a product recall. Understanding the nature of an impurity is a critical first step in determining whether the substance is recognized as a high-risk genotoxic impurity, a low-risk trace elemental impurity, or an unknown contaminant. However, identifying impurities can be complex, because they often surface as unknown peaks in a routine chromatogram. Their chemical nature can include both organic and inorganic molecules, and they can originate from multiple sources including starting materials, reaction intermediates and side products, or degradants.