Abstract
This study investigated physico-chemical drinking water quality of 115 water supply schemes of of District Mianwali along with estimating the health risks associated with the intake of arsenic and flouride in drinking water. One sample was collected from the source end while two samples were collected from consumer ends of each scheme. Overall results showed that 81% of the water samples were safe while 19% were unsafe for drinking purposes. Results showed that TDS (30%), chloride (15%), sulphate (40%), calcium (40%), sodium (14.2%), hardness (24%), nitrate (13%), flouride (30%), and arsenic (7%) exceeded World Health Organization (WHO) standards. Pearson correlation matrix also showed statistically significant relationships (p<0.01) between various physico-chemical parameters and statistically strong significant positive relationships (r = 0.68-1.00, p<0.01) between. TDS, Ca, SO42-, and hardness.There was no variation in the source and consumer end water quality. Risk assessment revealed a low potential health risk to the population of Mianwali for arsenic at source 0.4309<1 (mean) and consumer ends 0.70438<1 (mean), and F-0.4339<1 at source (mean) and 0.4068<1 (mean) at consumer ends. Hence, this study is in time for the authorities to act immediately, as Mianwali groundwater quality is deteriorating.