Characteristics of heavy metal content in wheat grains and human health risk assessment - A county in northern Henan Province

In order to evaluate the pollution characteristics and health risk of heavy metals in wheat grain, 283 wheat grain samples were collected from a county in northern Henan Province, and the contents of As, Pb, Cd and Cr in the samples were determined. The pollution degree of heavy metals in wheat grain in the study area was analyzed by pollution index method and health risk assessment, and the spatial distribution characteristics were revealed, and the human health risk was evaluated. The results showed that the average contents of As, Pb, Cd and Cr in wheat grains were 0.063, 0.053, 0.193 and 0.177 mg.kg(-1), respectively, and the exceeding rate of Cd was the highest. The comprehensive pollution index of heavy metals in wheat grains was 1.435, reaching the level of light pollution. The spatial classification results show that the factors such as nearby traffic and steel chemical enterprises are the main causes of high pollution. The minimum health risk indexes of As, Cd and Cr for adults and children were 6.32x10(-4), which exceeded the maximum acceptable risk range recommended by USEPA, and there was a high carcinogenic risk.