Abstract: The present invention pertains to the field of toxicological assessments for risk stratification of chemical compounds. Specifically, it relates to a method for diagnosing increased peroxisomal proliferation. It also relates to a method of determining whether a compound is capable of inducing such peroxisomal proliferation in a subject and to a method of identifying a drug for treating increased peroxisomal proliferation. Furthermore, the present invention relates to a data collection comprising characteristic values of at least five metabolites, a data storage medium comprising said data collection, and a system and a device for diagnosing increased peroxisomal proliferation. Finally, the present invention pertains to the use of a group of metabolites or means for the determination thereof for the manufacture of a diagnostic device or composition for diagnosing increased peroxisomal proliferation in a subject.