Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Key laboratory of Nonpoint Source Pollution Control, Ministry of Agriculture, Beijing 100081, China.
Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Key laboratory of Nonpoint Source Pollution Control, Ministry of Agriculture, Beijing 100081, China.
Sci Total Environ. 2018 May 1;622-623:1499-1508. doi: 10.1016/j.scitotenv.2017.09.317. Epub 2017 Oct 18.
Heavy metal(loid)s (HMs) in organic fertilizer have become a primary source of HMs pollution of farmlands, which could cause deleterious health effects in people exposed through soil-plant systems via multi-pathways. This study investigated China's main grain production area (Henan Province) to evaluate the accumulation and transport characteristics of HMs (Cr, Mn, Ni, Cu, Zn, As, Cd and Pb) in a soil-wheat system and conduct a health risk assessment for wheat (Triticum aestivum) grain under different nitrogenous fertilizer treatments. The results indicated that the Cr, Cu, As and Cd contents in soil were 56.21-113.66, 13.97-58.72, 5.79-22.62 and 0.04-0.23mg·kg, and the mean contents of Cr and As contents in wheat grains were 0.78±0.31 and 0.49±0.18mg·kg, respectively, which exceeded the corresponding standards. The bio-concentration factor and transfer factor were lowest in response to N-fertilization with N8-N15. Health risk assessment showed that the local population who ingested grain from culture condition of N15 experienced the lowest non-cancer and cancer risks. Among different population groups, HMs posed relatively higher non-cancer and cancer risks to children aged 0-5years. Furthermore, Cr and As exposure was the greatest contributor to Hazard Index (HI), accounting for 74.72-83.11%, while Cr exposure accounted for >90% of the total potential cancer risk. Concluding, this study indicated that, to protect human health, the current application of nitrogenous fertilizer should be controlled to an appropriate level.
重金属（loid）s 在有机肥中已成为农田重金属污染的主要来源，通过土壤-植物系统，经多种途径暴露于其中的人群可能会受到有害健康的影响。本研究以中国主要粮食产区（河南省）为对象，评估了土壤-小麦系统中重金属（Cr、Mn、Ni、Cu、Zn、As、Cd 和 Pb）的积累和迁移特征，并对不同氮肥处理下小麦（Triticum aestivum）籽粒进行了健康风险评估。结果表明，土壤中 Cr、Cu、As 和 Cd 的含量分别为 56.21-113.66、13.97-58.72、5.79-22.62 和 0.04-0.23mg·kg-1，小麦籽粒中 Cr 和 As 的平均含量分别为 0.78±0.31 和 0.49±0.18mg·kg-1，均超过了相应的标准。N 肥处理下，N8-N15 的生物浓缩因子和转移因子最低。健康风险评估表明，摄入 N15 培养条件下粮食的当地居民面临的非癌症和癌症风险最低。在不同人群中，儿童（0-5 岁）面临的重金属非癌症和癌症风险相对较高。此外，Cr 和 As 的暴露对危害指数（HI）的贡献最大，占 74.72-83.11%，而 Cr 的暴露占总潜在癌症风险的>90%。综上所述，本研究表明，为了保护人类健康，应将当前氮肥的施用量控制在适当水平。
