广州郊区土壤-作物镉富集及其健康风险评价  

Cadmium Accumulation and Health Risk Assessment of Soil-Crops in the Suburban of Guangzhou

作　　者：韩瑜 常春英 张晓露 邓一荣 庄长伟 HAN Yu;CHANG Chunying;ZHANG Xiaolu;DENG Yirong;ZHUANG Changwei(Guangdong Key Laboratory of Contaminated Environmental Management and Remediation,Guangdong Provincial Academy of Environmental Science,Guangzhou 510045,China)

机构地区：[1]广东省环境科学研究院,广东省污染场地环境管理与修复重点实验室,广东广州510045

出　　处：《环境科学与技术》2023年第7期228-236,共9页Environmental Science & Technology

基　　金：国家自然科学基金项目(41907337);广州市珠江科技新星专项(201806010086)。

摘　　要：土壤-作物系统重金属迁移富集、健康风险研究一直是土壤环境相关研究的热点话题,城市郊区耕地土壤的作物种植因其受人为活动的影响较大而备受关注。该文以广州市郊区土壤与叶菜、土壤与水稻系统为研究对象,研究重金属镉(Cd)的迁移富集特征、影响因素及健康风险。结果表明,研究区土壤重金属Cd有一定的累积性,与GB 15618-2018规定的农用地土壤污染风险筛选值相比,稻田土壤和菜地土壤中分别有3个点位和11个点位属于安全利用类,均无严格管控类点位;与GB 2762-2022规定的污染物限值(0.2 mg/kg)相比,稻米和叶菜样品中分别有1个和3个样品Cd含量超过标准限值。作物可食用部分对土壤中CaCl2提取态Cd富集能力最强,富集能力排序为稻根>稻秆>叶菜>稻米。pH、有机质(OM)和阳离子交换量(CEC)均是影响土壤重金属Cd有效态含量的重要因素,其中以pH最为显著。儿童食用该地区种植作物的健康风险较成人高,其中儿童食用叶菜摄入Cd的危害系数大于1,可能存在潜在的健康风险,应予以关注。The study of heavy metal migration and accumulation and health risks in soil-crop systems has always been a hot topic in soil environment research.Crop cultivation in suburban cultivated soil has attracted much attention because of its increased influence by human activities.Taking soil-leaf vegetables and soil-rice systems in the suburban of Guangzhou as the research objects,the migration and accumulation characteristics,influencing factors and health risks of cadmium(Cd)were studied.The results showed that the heavy metal Cd in the soil of the study area had a certain accumulation.Compared with the screening value of soil pollution risk of agricultural land stipulated by GB 15618-2018,3 sites in paddy soil and 11 sites in vegetable soil belonged to the safe utilization class,and none of them belonged to the strict control class.Compared with the pollutant limit(0.2 mg/kg)stipulated by GB 2762-2022,the content of Cd in 1 rice sample and 3 leafy vegetable samples exceeded the standard limit,respectively.The edible part of the crop had the greatest ability to accumulate CaCl_(2)-Cd in the soil,and the accumulate ability was ranked as rice root>rice straw>leaf vegetable>rice.pH,organic matter(OM)and cation exchange capacity(CEC)are all important factors affecting the available content of heavy metal Cd in soil,and pH is the most significant.The health risk of children eating crops grown in this area is higher than that of adults.Among them,the risk factor of Cd ingested by children eating leafy vegetables is greater than 1,which may be a potential health risk and should be paid attention to.

关 键 词：镉污染 农产品 富集 健康风险评估 

分 类 号：X820.4[环境科学与工程—环境工程] X53