title: Fluoride Content of Bottled Drinking Water in Chennai, Tamilnadu.
abstract: BACKGROUND
  The optimum level of fluoride in drinking water is 0.7 to 1.2 ppm. Decreased fluoride concentration leads to increased risk of caries and increased concentration can lead to dental or skeletal fluorosis. One crore liters of water is supplied to Chennai and surrounding areas through pouches and bottles which carters about one third of city population.
  
  
  OBJECTIVE
  The aim of this study is to determine the fluoride concentration in top 10 bottled waters in Chennai and to check the accuracy of their labelling.
  
  
  METHODS
  Top selling bottled waters, 6 multinational and 4 Non- multinational brands were selected for the study. Three different batches of each brand were purchased. The labels of the bottled were removed after collecting the details regarding fluoride content. All the bottles were numbered and sent for fluoride content analysis using SPADNS calorimetric method.
  
  
  RESULTS
  All the brands and batches which were analysed for the study had less than optimal fluoride content and there is a significant variation in fluoride concentration of each brand and among different batches of same brand bottled waters. The range of fluoride level in tested samples was between 0.27 to 0.59. Only one brand's label had information regarding the fluoride content.
  
  
  CONCLUSIONS
  Standardization of fluoride levels in bottled waters and labelling of fluoride content should become mandatory.
authors.affiliation: Reader, Department of Pedodontics, Saveetha Dental College and Hospitals , Chennai, India .
authors.forename: Sujatha
authors.initials: S
authors.lastname: Somasundaram
authors.affiliation: Student, School of Public Health, SRM University , Chennai, India .
authors.forename: Karunya
authors.initials: K
authors.lastname: Ravi
authors.affiliation: Senior Lecturer, Department of Periodontics, SRM Kattankulathur Dental College , Chennai, India .
authors.forename: K
authors.initials: K
authors.lastname: Rajapandian
authors.affiliation: Reader, Department of Pedodontics, Saveetha Dental College and Hospitals , Chennai, India .
authors.forename: Deepa
authors.initials: D
authors.lastname: Gurunathan
keywords: Bottled water; SPADNS colorimetric analysis