Genotoxic impurities concerns

Concerns over the safety of tiny amounts of potential genotoxic impurities in APIs were driven by major advances in analytical instrumentation that allow detection of these impurities at parts per million levels. 

The issue of potential genotoxic impurities (PGIs) in active pharmaceutical ingredients (APIs) and drug products continues to receive considerable attention. Alkyl halides are well-known to be potentially genotoxic and are, hence, a safety concern in medicinal chemistry. ... 

Although genotoxicity studies have been performed on the majority of IFNs and ILs, such studies have been justified based upon potential concerns regarding contaminants or impurities rather than concerns regarding the active substance. Routine assessment of genotoxic potential is not recommended. 

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