chromium, nickel and manganese in the groundwater resources of asadabad plain, iran

background & aims of the study: heavy metals are one of the most important environmental pollutants which agricultural and industrial activities and urban development increased their entry rate to the underground resources. this study aimed to investigate the concentration of chromium, nickel and manganese in groundwater resources in asadabad plain. materials & methods: sampling of groundwater done in 2015 autumn. in this study, according to the cochran’s sample size formula, tote formula, totally 60 samples of groundwater of asadabad plain were collected from 20 wells and after preparation stage with atomic device, elements concentration of samples is read. to analysis of data spss 19 with significant level of 0.50 is used. results: the concentration average of chromium, nickel and manganese equal to 0.044¬ ±0.016, 70.42±10.83 and 2.64±0.83 ppb. the comparison results of the concentration average of elements based on who and isiri standard shows the concentration average of elements is lower than standard level. conclusions: currently the groundwater resources of asadabad plain are not polluted with heavy metals, but long-term excessive use of agricultural inputs and construction of polluting industries can cause a threat to groundwater resources in this area.