Heavy Metal Pollution Characteristics and Health Risk Assessment of Soil-crops System in Anhui Section of the Yangtze River Basin

Abstract

In order to explore the pollution characteristics and health risks of heavy metals in a soil-crop system in the Anhui section of the Yangtze River basin, a total of 338 groups of soil samples from rice, wheat, and their roots were collected, and the contents of eight types of heavy metals were determined. Additionally, the pollution index method, potential ecological hazard, multivariate statistical analysis, and health risk were used to evaluate the heavy metal content in rice and wheat root soil. The results showed that Cd, Cu, Cr, and Ni in the soil had an obvious accumulation effect, and the pollution of rice root soil was more serious than that of wheat soil. The potential ecological risk was mild to moderate, which mainly came from the elements Cd and Hg. Multivariate statistical analysis showed that Cu, Pb, Zn, and Cd were industrial sources and agricultural sources; Cr and Ni were natural sources; and As and Hg were agricultural sources. The absorption and enrichment intensity of heavy metals by rice was in the order of Cd>Zn>Cu>Hg>Ni>As>Cr=Pb, and those in wheat were ordered as Zn>Cd>Cu>Hg>Ni>As=Pb>Cr. The root soil heavy metal health risk assessment indicated that oral intake was the main exposure route of non-carcinogenic risk, and children were more vulnerable to heavy metal pollution. Non-carcinogenic risk assessment showed that wheat root soil posed non-carcinogenic risk to children but no carcinogenic risk. Intake of rice and wheat had some degree of non-carcinogenic risk and unacceptable carcinogenic risk for both adults and children.