Biomarkers of fluoride exposure in human body

Fluoride is often called as a “Double-edged sword”, as inadequate ingestion is associated with dental caries and excessive consumption of fluorides in various forms leads to some deleterious effects on different tissues of the body such as teeth, bone and soft tissues. Due to the changing patterns of systemic fluoride exposure, there is an increase in the prevalence and severity of dental fluorosis. Therefore, it is extremely important to monitor the intake of fluoride in order to help scientists and policymakers to make better informed decisions about the best ways to balance dental caries prevention versus dental fluorosis risk. This can be done by monitoring level of various biomarkers available in human body. Biomarker is defined as “an indicator of change in biological system that could lead to a clinical disease”. The World Health Organization has stated that “a fluoride biomarker is of value primarily for identifying and monitoring deficient or excessive intakes of biologically available fluoride”. Fluoride biomarkers can be classified under the categories: contemporary (urine, plasma and saliva), recent (nails and hair) and historic markers (bone and teeth). These biomarkers can also serve as a tool to assess the impact of water fluoridation on bone quality and other physiological conditions. This literature review is presented with an objective to discuss various aspects of different biomarkers of fluoride exposure in human body and their significance in research, human health and dental health services.