Metabolomics evaluation of hydroxyproline as a potential marker of melamine and cyanuric acid nephrotoxicity in male and female Fischer F344 rats

► Metabolomics biomarker evaluation after exposure to melamine and cyanuric acid. ► Melamine and cyanuric acid affected males slightly more than females. ► Hydroxyproline increased consistent with clinical chemistry and histopathology. ► Hydroxyproline may be a marker of melamine and cyanuric acid-induced kidney injury.