Human health risk assessment of heavy metals in the soil–Panax notoginseng system in Yunnan province, China

In this study, a total of 69 topsoil samples and 10 Panax notoginseng samples from Yunnan Province were collected and the concentrations of As, Cd, Cu, Hg, Ni, Pb and Zn in all the samples were determined. The hazard index (HI), total carcinogenic risk (TCR) and estimated daily intake (EDI) of heavy metals were calculated to assess the health risk of P. notoginseng growers and consumers. The average concentrations of As, Cd, Cu, Hg, Ni, Pb and Zn in P. notoginseng planting soils are 43.6, 0.55, 50.8, 0.30, 73.4, 58.2, and 161 mg/kg, respectively. The average Nemerow integrated pollution index of heavy metals in soils is 1.8, indicating that the P. notoginseng planting soils are slightly polluted by those heavy metals. The average HI value is 1.29 and the TCR value of As is above the threshold value, suggesting that As pollution in soil has adverse impact on local growers' health. P. notoginseng is polluted by Cd, As and Pb. 39.1% of estimated daily intakes of As for P. notoginseng consumers through leaf consumption exceeding its permitted daily exposure dosages, suggesting that there is a potential health risk for P. notoginseng consumers to consume P. notoginseng leaves.