n-Hexane is an important aliphatic compound. It is widely used in the industry to make glue, paints, varnishes, and printing inks and in shoe manufacturing and repair. Occupational or experimental exposure to n-hexane can lead to serious impairment of the nervous system, classified as a centralperipheral distal degenerative axonopathy. Occupational exposure level is monitored by measuring the urinary level of 2,5-Hexandione (2,5-HD), the major metabolite of n-Hexane. n-Hexane is metabolized to several intermediates besides 2,5-HD. Most of its intermediates undergo further transformation and are excreted as glucuronide conjugates. Transformation of n-Hexane intermediates to 2,5-HD by acid hydrolysis significantly increases the amount of 2,5-HD detected. The 2,5-HD measured as a result of free and acid hydrolysis is measured as the “total” amount.