Indeed, there is data to work with allowing to address the topic in the risk assessment, which has been accepted by regulators.
Luckily these would have to be non-amino acid related then based on structure and have already been evaluated in the step 2 where identified.
This study also concludes pyrrolidine, piperidine, piperazine, morpholine to be non-tumorigenic under the same conditions. The study might not have adequate positive control to support N-PRO is not carcinogenic. Has anyone found a stronger study concluding N-PRO to be non-carcinogenic?