GIS-based Assessment of Arsenic Contamination of Water Supplies in Rural Areas of Rivash Town: Comparisons with National and WHO Standards

Arsenic is one of the most hazardous elements in drinking water. Water contaminated with arsenic causes a variety of diseases in humans including cancer. The present study was conducted to survey Arsenic concentration in rural water resources in Rivash Twon, Kashmar, Iran. For the purposes of this cross-sectional study, 60 samples were collected from 10 underground drinking water supplies during the period from April to June, 2013. Samplings and sample preservation were performed according to standard methods. Measurements were performed via the VGA method using atomic absorption. Such water quality parameters as pH, TDS, EC, residual chlorine, and temperaturte were also measured to determine any relationships likely to exist between As concentration and the parameters measured. As levels were then compared with national and international standards. It was found that the average values of As concentration at the stations A, B, C, D, E, F, G, H, I, and J were 1.53±1.03, 1.30±1.07, 10.55±3.83, 11.21±5.01, 10.57±3.68, 2.34±0.73, 3.22±0.58, 9.89±3.57, 10.48±5.07, and 2.23±0.53 µg/L-1, respectively. As concentrations at five stations were found to be higher than the values recommended in WHO guidelines; the remaining stations revealed values below the national standard. While the differences between As level and the national standard were statistically significant (p