ACD/Percepta Impurities Suite—Impurities Package for the Assessment of Genotoxic and Carcinogenic Risk

ACD/Labs Package for Toxicity Screening of Impurities provides a battery of in silico tests to accurately assess the genotoxic and carcinogenic potential of impurities and degradants, found to be below the threshold of toxicological concern in drug products, helping companies remain compliant with regulatory submission requirements.

Profile impurities using predictions for genotoxic and carcinogenic endpoints, quickly determine if an impurity is likely to pose a safety risk, and identify potentially hazardous structural fragments responsible for toxic activity.

The toxicity predictions in the Impurities Package offer greater insight into the safety of impurities, providing detailed information on toxic endpoints, reflecting various mechanisms of hazardous activity including:

  • Mutagenicity (Ames test, Mouse Lymphoma Assay, and other standard assays)
  • Clastogenicity (Micronucleus test, Chromosomal Aberrations)
  • DNA damage mechanisms (Unscheduled DNA Synthesis)
  • Carcinogenicity (FDA rodent carcinogenicity data)
  • Endocrine disruption mechanisms (estrogen receptor binding)

The impurities package offers probabilistic predictive models for 21 different endpoints that cover various mechanisms of hazardous activity presented above. These predictors are supplemented with a knowledge-based expert system that identifies potentially hazardous structural fragments that could be responsible for genotoxic and/or carcinogenic activity of the compound of interest.

The expert system contains a list of 67 alerting groups of toxicophores, 53 of which account for point mutational and/or clastogenic mechanisms of DNA damage, while the remaining 14 substructures detect carcinogens acting by non-genotoxic mechanisms. The expert system was able to recognize >94% of mutagens in ACD/Ames test database, and >90% of compounds marked as potent carcinogens in the FDA's OFAS Food-Additive Knowledgebase.


  • Predict the genotoxic and carcinogenic effects of an impurity from simple structure input (name, 2D structure, SMILES string), with a reliability index generated by the probabilistic models
  • Identify potentially hazardous structural fragments responsible for carcinogenic and genotoxic activity
  • Gain insight into the possible mechanisms of toxic effects
  • See a display of up to 5 similar structures with experimental results in relevant bioassays
  • Perform batch calculations of large impurity libraries with batch modules
  • Access the searchable Ames test database by structure and a variety of parameters


  • Gain a clearer understanding of the toxicity profile of impurities
  • Provide timely information to accelerate regulatory drug submissions
  • Reduce experimental testing for genotoxicity using in silico predictions