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High fluoride groundwater leads a health threat to millions of people around the world. This paper  analyzes  the  most  extensive  database  on  fluoride  and  other  chemical  constituent distribution in arid tract of Ottapidaram block, Tamilnadu, India where it is the only source of drinking  water.  The  study  was  conducted  in  the  summer  season  (May –  June,  2010).  The
water  samples  of  61  village  panchayats  were  tested;  81.97%  had  injurious  fluoride  level above than 1.5 mg/L. The fluoride concentration in drinking waters varied from 0.936 to 4.34 mg/L  in  the study  area.  Due  to  the  high  concentration  of  fluoride, dental  fluorosis  was  also
identified. Majority of the samples do not comply with Indian as well as WHO standards for most  of  the  water  quality  parameter.  In  addition,  Fluoride  concentration  was  not  correlated with  other  physicochemical  parameters  significantly  in  ground  water.  Overall  water  quality
was  found  as  unsatisfactory  for  drinking  purposes  without  any  prior  treatment  except  at eleven locations out of 61.