Concentration of lead and mercury in collected vegetables and herbs from Markazi province, Iran: a non-carcinogenic risk assessment

The current study was undertaken to determine the concentration of Hg and Pb in ten types of collected green leafy vegetables and herbs from different agricultural sites of Markazi province, Iran as well as the gathered water and soil around them using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, the potential health risk assessment by using target hazard quotient (THQ) and hazard index (HI) parameters was estimated. Based on the accumulation order, Artemisia dracunculus L with 56.147 ± 17.30 μg/kg and Spinacia oleracea L with 1733.62 ± 2264.7 μg/kg can uptake and accumulate more concentration of Pb and Hg in their tissues, respectively. Regarding gathered soil around vegetables, the concentration of Hg and Pb were measured as 52.056 ± 16.25 μg/kg and 4993.83 ± 1287.8 μg/kg, respectively. The transfer factor (TF) demonstrated that vegetables and herbs could absorb a high amount of Hg from the soil while these plants uptake less concentration of Pb thought their green leaves. The non-carcinogenic risk assessment showed the minimum, and maximum THQ was related to 15-24 and 35-44 age groups in the urban and rural consumers. Also, HI in the urban and rural areas was calculated as 8.492 and 9.012, respectively. Since HI > 1, exposure of the urban and rural areas of Markazi province to non-carcinogenic risk by consuming the green leafy vegetables and herbs is a source of concern.