Background:Exposure of human being to fluoride occurs through various sources as food, water, toothpastes and fluoride additives. This exposure is either to low concentrations for long periods or to high concentrations and both may lead to poisoning.  Folic acid (FA) has an important free radical scavenging property which makes it the most potent antioxidants. Moreover, it suppresses apoptosis and boost cell survival.
Aim of the work: To evaluate the protective and therapeutic role of FA against sodium fluoride (NaF) induced toxicity on adult male rat skin.
Materials and Methods:Forty adult (3 months) male albino rats(weighing 200-220 gm) were equally divided into 4 groups (10 rats each):group 1 (control),group 2 (NaF, for 4 weeks),group 3 (NaF, for 4 weeks followed by FA for another 4 weeks) and group 4 (NaF plus FA for 4 weeks). Both NaF (25mg/Kg b.w.) and FA (8 mg/Kg b.w.) were given orally daily. The rats were sacrificed and samples of the back skin were processed for histological, immunohistochemical (Bcl2 antiapoptotic protein) and morphometric studies.
Results:Group 2 revealed signs of degeneration in epidermal cells, expansion of intercellular spaces and destructed organelles. There wasa reduction in epidermal thickness with disturbance in collagen fibers arrangement and weak immunoreactivity of Bcl-2. FA induced relative improvement in the dermal and epidermal structures in group 3 while there was preservation of these structures in group 4.
Conclusion:FA ameliorates NaF induced harmful effects on skin in addition to its valuable preventive role.