accumulation and soil-to-plant transfer factor of lead and manganese in some plant species in semnan province, central iran

background: heavy metals have detrimental effects on the health of human being. the values of manganese (mn) and lead (pb) in some plant species and soil samples in an arid area of iran were evaluated in this study. methods: the values of pb and mn in 94 plant samples from 8 plant species and the related soil samples in 2010 were considered in shahroud and damghan, central iran. moreover, the soil-to-plant transfer factors of these two elements were investigated. results: except for barley, the values of pb in all of the considered plants were higher than the standard level of 0.3 mg/kg. the amounts of mn in all of the plant species other than pistachio were higher than the standard level of 25 mg/kg. as a whole, the bio-concentration factor of mn was higher than that of pb in the study area. conclusion: none of the soil-to-plant transfer factors exceeded one. grape recorded the highest amounts of pb and mn compared with that of other investigated plant species. however, since its respective bio concentration factor (bcf) was lower than one, it cannot be considered as a hyper accumulator of lead and manganese.