comparative study on lead, cadmium and arsenic concentration of alfalfa forage in tehran province

Background: this research aims to evaluate heavy metals contamination of alfalfa forage and soil in industrial and non-industrial regions of tehran province. the soil and plant samples were collected from alfalfa fields situated in industrial and non-industrial areas during two harvests of alfalfa harvest. methods: the electrothermal atomizers spectroscopy technique was employed to measure the heavy metals (lead, arsenic, and cadmium) levels in the samples. a flame atomic absorption spectrometer equipped with acetylene-air flame was employed. results: the highest heavy metals concentrations were detected in the soil and alfalfa samples from the industrial regions. lead had the highest level in the soil followed by arsenic and cadmium; the same trend held for the alfalfa as well. moreover, the heavy metal content in alfalfa declined from the first to second harvest, while it increased in the soil. the heavy metals content of alfalfa was below the maximum permitted concentration for feedstuffs and livestock. the highest soil-plant transfer factor of heavy metals was detected in the first harvesting. the highest arsenic transfer factor was recorded in the industrial areas. conclusion: the findings of the current study can be helpful in the determination of healthy forage in various areas.