Benzo[c]phenanthrene-d5 is primarily used as an internal standard in analytical chemistry, particularly in mass spectrometry and gas chromatography. Its deuterated form allows for precise quantification and identification of non-deuterated benzo[c]phenanthrene in complex mixtures, such as environmental samples or biological matrices. This compound aids in studying the presence and behavior of polycyclic aromatic hydrocarbons (PAHs) in various settings, including pollution monitoring and toxicological research. Its application ensures accurate measurements by compensating for potential variations during sample preparation and analysis.