Occupational exposure to Cr is found among approximately half a million industrial workers worldwide. Also, water contaminated with hexavalent chromium is a worldwide problem, as it is the major route of chromium exposure for the general population [8] and [9]. Potassium dichromate (K2Cr2O7) is a soluble hexavalent chromium compound that is widely used in several industries [10].
Ascorbic acid (vitamin C) is as an essential micronutrient that performs important metabolic function in human [11]. It also acts as a biological antioxidant by donating an electron to free radical species, such as tocopherol radical, thereby interrupting the radical chain reaction in biological membranes [12].
Vitamin C has been reported to function as a major reductant of Cr(VI) in animals and cell culture systems [13]. From these points it was important to evaluate the effect of potassium dichromate on the thyroid gland of rats and the possible protective effect of vitamin C.