Concentration characteristics and health risk of heavy metals in soil and maize with long-term application of swine manures in farmland of Jilin Province

The application of livestock manure in farmland can cause the accumulation of heavy metals in soil and crops.The heavy metals can be transmitted through the biological chain, ultimately affecting the health of the populace.The maize fields with long-term swine manure application around seven large hog farms in Jilin Province were selected to study the concentration characteristics of heavy metals in soil and maize grains, and to clarify the effects of livestock manure application on soil quality and population health.The results showed that the average concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in soil were 9.430, 0.128, 31.21, 28.15, 0.021, 19.60, 26.00 and 71.76 mg·kg^-1, respectively.The average concentrations of As, Cd, Cu, Pb and Zn were higher than the soil background values in Jilin Province.Geo-accumulation index and Nemerow integrated pollution index were used to evaluate the pollution status of soil.The pollution levels of Cu and As in soil were with the highest values, reaching light-moderate pollution level, and the comprehensive pollution was at the safety level.The average concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in maize grains were 0.164, 0.036, 0.698, 2.196, 0.0038, 0.357, 0.295 and 25.23 mg·kg^-1, respectively, and the concentrations of Pb, Ni and Zn exceeded the National Food Hygiene Standards to varying degrees.The enrichment ability of different heavy metals in maize grains had great diversity, the enrichment degree of Zn was with the highest value, and the enrichment degree of Pb was with the lowest value.The health risk of heavy metals to adults was small, the health risk index of As to children was greater than 1, while the comprehensive health risk of both adults and children was greater than 1, indicating that maize with long-term application of swine manure has certain health risks.