analysis of heavy metals in vegetables cultivated in the kashafrud’s riverside, razavi khorasan province, iran

Abstract: nowadays, due to the risk related to eating vegetables contaminated with heavy metal ions, the safety of vegetables for consumption is becoming an increasing concern to consumers. industrialization, unrestrained human population, urbanization, and over-usage of pesticide can be within the major reasons’ category of heavy metals (hms) contamination in the food chain. the present study was conducted to quantify some heavy metal ions and to evaluate their sources and health risks in various samples. these samples included alfalfa, barley leaves, beet, and beet leaves. in addition, these samples' agricultural soil, irrigation water, and treated and untreated wastewater of charmshahr industrial town of mashhad was analyzed for heavy metal ions including fe, co, cd, zn, cu, cr, pb, and ni by inductively coupled plasma – optical emission spectrometry (icp-oes). results showed that among eight heavy metal ions, five hms including fe, co, zn, cu, and cr were more than the safety limits given by the food and agriculture organization (fao) and the world health organization (who) for human consumption. the rest of hms showed lower levels than those of permissible amounts. overall, the number of heavy metal ions that were exceeding the permissible values set by fao/who, were beet leaves > alfalfa> barley and beet > all water samples except the beet irrigation water, respectively. the leaf of vegetables contained more heavy metal ions and were exceeding the permissible levels given by fao/who as compared with the vegetable itself. to be more precise, the concentration of heavy metal ions including fe, co, and cr, in the beet’s leaves was more than the root of the beet. however, the concentrations of chromium in most samples were higher than the allowable level, which indicates the existence of several tanneries around the river.