1. Southeast Sichuan Geological Group, Chongqing Bureau of Geology and Minerals Exploration, Chongqing 400038, China 2. Chongqing Key Laboratory of Land Quality Geological Survey, Chongqing 400038, China
This study aims to systematically assess the pollution risk of heavy metals in the soil-crop-human body system along the periphery of mining areas, thus providing a scientific basis for the classified management of ecological risks and safe crop production in mining areas. Hence, this study examined the soil and crops (rice, corn, and sweet potato) in arable land along the periphery of a typical mercury mining area in Chongqing City. The single-factor pollution index (Pi), Nemero composite index (P综), and positive matrix factorization (PMF) model were employed to assess the pollution degree and ecological risk of soil heavy metals for source analysis. Moreover, the human health risk assessment model recommended by the United States Environmental Protection Agency (USEPA) was applied to assess the health risks of local staple crops for residents. The results are as follows: (1) The average contents of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the soil of the study area were all higher than the topsoil background values of Chongqing and China, suggesting that heavy metals are relatively enriched in topsoil; (2) The single-factor pollution index indicates that the over-limit ratios of Hg and Cd in the soil reached 96.29% and 92.59%, respectively, whereas rice, corn, and sweet potato samples with Cd content exceeding the value specified in the national food safety standard (GB 2762—2022) accounted for 16.67%, 18.75%, and 14.28%, respectively; (3) The Nemero composite index (P综) was between 1.17 and 46.05, suggesting mild to heavy pollution in the study area, with heavy pollution primarily located around the mercury mining area and artisanal mercury smelters, as well as the lower reaches of the Rongxi River; (4) The PMF model analysis demonstrates that the heavy metals in the soil of the study area originate from three sources: natural source (47.21%), mining activities (16.00%), and a mixed source of mining and agricultural activities (36.79%). Specifically, Cd, Cr, and Ni are principally affected by the natural source, Hg by mining activities, As and Pb by the mixed source of mining and agricultural activities, and Cu and Zn are associated with the natural source and the mixed source of mining and agricultural activities; (5) The human health risk model reveals that the consumption of rice, corn, and sweet potato poses composite health risks for both adults and children. Rice consumption exhibits the highest risk index, especially in children, with the main risk factors being As and Cd.
余飞, 王锐, 周皎, 张风雷, 蒋玉莲, 张云逸, 朱世林. 典型汞矿区周边耕地土壤重金属来源解析与农作物健康风险评价[J]. 物探与化探, 2024, 48(3): 847-857.
YU Fei, WANG Rui, ZHOU Jiao, ZHANG Feng-Lei, JIANG Yu-Lian, ZHANG Yun-Yi, ZHU Shi-Lin. Sources of soil heavy metals and health risk assessment of crops in arable land at the periphery of a typical mercury mining area. Geophysical and Geochemical Exploration, 2024, 48(3): 847-857.
Fig.3 内梅罗综合指数法评价结果 Evaluation results of P综 in the study area
Fig.4 研究区土壤重金属污染源成分谱
参数
As
Cd
Cr
Cu
Hg
Ni
Pb
Zn
水稻
最小值/10-6
0.07
0.00
0.06
0.73
0.00
0.16
0.05
15.50
最大值/10-6
0.42
1.20
0.23
3.20
0.01
0.58
0.05
25.00
平均值/10-6
0.24
0.19
0.10
1.95
0.01
0.29
0.05
19.60
超标率/%
0.00
16.67
0.00
-
0.00
-
0.00
-
富集因子
0.019
0.187
0.001
0.050
0.007
0.007
0.001
0.168
玉米
最小值/10-6
0.01
0.01
0.06
1.30
0.00
0.14
ND
16.00
最大值/10-6
0.01
0.14
0.10
2.80
0.00
0.70
ND
25.10
平均值/10-6
0.01
0.05
0.08
1.93
0.00
0.36
ND
18.32
超标率/%
0.00
18.75
0.00
-
0.00
-
0.00
-
富集因子
0.001
0.070
0.001
0.044
0.010
0.008
ND
0.144
红薯
最小值/10-6
0.01
0.01
0.04
1.60
0.00
0.16
0.02
2.00
最大值/10-6
0.02
0.19
0.06
2.40
0.00
0.69
0.05
3.80
平均值/10-6
0.02
0.06
0.05
2.06
0.00
0.34
0.04
3.09
超标率/%
0.00
28.57
0.00
-
0.00
-
0.00
-
富集因子
0.001
0.038
0.001
0.053
0.004
0.006
0.001
0.025
Table 5 研究区耕地土壤重金属含量特征
重金属
CDI
HQ
成人
儿童
成人
儿童
水稻
玉米
红薯
水稻
玉米
红薯
水稻
玉米
红薯
水稻
玉米
红薯
As
0.0010
0.0000
0.0001
0.0026
0.0001
0.0001
3.381
0.098
0.184
8.678
0.252
0.471
Cd
0.0008
0.0002
0.0002
0.0021
0.0006
0.0005
0.834
0.230
0.199
2.140
0.591
0.511
Cr
0.0004
0.0003
0.0002
0.0011
0.0008
0.0006
0.000
0.000
0.000
0.001
0.001
0.000
Cu
0.0084
0.0083
0.0088
0.0214
0.0212
0.0226
0.209
0.207
0.220
0.536
0.531
0.566
Hg
0.0000
0.0000
0.0000
0.0001
0.0000
0.0000
0.080
0.052
0.027
0.206
0.133
0.070
Ni
0.0012
0.0015
0.0015
0.0032
0.0040
0.0037
0.062
0.077
0.073
0.158
0.198
0.187
Pb
0.0002
-
0.0002
0.0006
-
0.0004
0.054
-
0.039
0.138
-
0.099
Zn
0.0840
0.0785
0.0132
0.2156
0.2015
0.0339
0.280
0.262
0.044
0.719
0.672
0.113
THQ
4.899
0.926
0.786
12.575
2.376
2.018
Table 6 农作物的重金属摄入量及健康风险指数
[1]
Xiao R, Wang S, Li R H, et al. Soil heavy metal contamination and health risks associated with artisanal gold mining in Tongguan,Shaanxi,China[J]. Ecotoxicology and Environmental Safety, 2017,141:17-24.
Chen M, Pan Y X, Huang Y X, et al. Spatial distribution and sources of heavy metals in soil of a typical lead-zinc mining area,Yangshuo[J]. Environmental Science, 2022, 43(10):4545-4555.
Zhou Y, Chen Q, Deng S P, et al. Principal component analysis and ecological risk assessment of heavy metals in farmland soils around a Pb-Zn mine in southwestern China[J]. Environmental Science, 2018, 39(6):2884-2892.
Yu F, Zhang Y W, Yan M S, et al. Heavy metal pollution and human health risks assessment of soil and crops near the mercury ore in Chongqing[J]. Environmental Chemistry, 2022, 41(2):536-548.
Jia Y Q, Liu W Z, Qin J H, et al. Pollution and risk assessment of heavy metals in soil and agricultural products around mercury mining areas[J]. Nonferrous Metals:Extractive Metallurgy, 2021(3):43-50.
Chen H, Wang Y, Wang S. Source analysis and pollution assessment of heavy metals in farmland soil around Tongshan mining area[J]. Environmental Science, 2022, 43(5):2719-2731.
Zhan T L, Huang Y, Teng Y, et al. Pollution characteristics and sources of heavy metals in farmland soil in Wanshan mining areas,Guizhou Province[J]. Chinese Journal of Soil Science, 2017, 48(2):474-480.
Ni X R, Long M R, Yang R D, et al. Heavy metal contents of soil-maizes and its ecological effects in mercury mining area of Danzhai paiting,Guizhou[J]. Asian Journal of Ecotoxicology, 2020, 15(6):324-333.
Li Y H, Sun H F, Yang L S, et al. Mercury transport in soil-rice system and its health risk in Fenghuang tea field mercury mining area,Hunan Province[J]. Geographical Research, 2012, 31(1):63-70.
[10]
Zhang L, Jin Y Q, Lu J L, et al. Concentration,distribution and bioaccumulation of mercury in the Xunyang mercury mining area,Shaanxi Province,China[J]. Applied Geochemistry, 2009, 24(5):950-956.
[11]
Zhang H, Feng X B, Larssen T, et al. Bioaccumulation of methylmercury versus inorganic mercury in rice (Oryza sativa L.) grain[J]. Environmental Science & Technology, 2010, 44(12):4499-4504.
[12]
Zhao L, Qiu G L, Anderson C W N, et al. Mercury methylation in rice paddies and its possible controlling factors in the Hg mining area,Guizhou Province,Southwest China[J]. Environmental Pollution, 2016,215:1-9.
[13]
林勇征. 贵州万山汞矿区地球化学特征及环境质量评价[D]. 成都: 成都理工大学, 2017.
[13]
Lin Y Z. The geochemical characteristics and environmentalevaluation of quality in mercury mine area of Guizhou wanshan[D]. Chengdu: Chengdu University of Technology, 2017.
Wang R, Deng H, Jia Z M, et al. Spatial distribution characteristics,pollution,and ecological risk assessment of soil heavy metals around mercury mining areas[J]. Environmental Science, 2021, 42(6):3018-3027.
[15]
李柳. 溪口汞矿地区汞环境污染现状及风险评价研究[D]. 重庆: 重庆大学, 2014.
[15]
Li L. Study on environmental pollution status and risk assessment of mercury in Xikou mercury mining area[D]. Chongqing: Chongqing University, 2014.
[16]
Xu X H, Lin Y, Meng B, et al. The impact of an abandoned mercury mine on the environment in the Xiushan region,Chongqing,southwestern China[J]. Applied Geochemistry, 2018,88:267-275.
Xia Y. The geochemical characteristcs of fluid inclusions from the Yangshikeng mercury deposit,Sichuan,China[J]. Mineral Resources and Geology, 1992, 6(4):313-317.
Ministry of Land and Resources of the People's Republic of China. DZ/T 0295—2016 Standard for geochemical evaluation of land quality [S]. Beijing: Geological Publishing House, 2016.
[19]
中国地质调查局.DD 2005-03生态地球化学评价样品分析技术要求(试行)[S]. 2005.
[19]
China Geological Survey. DD2005-03 Technical requirements for sample analysis for ecogeochemical evaluation (Trial)[S]. 2005.
Wang R, Deng H, Jia Z M, et al. Concentration and pollution evaluation of heavy metals in soil and corn in high geological background area:Taking Chengkou County as an example[J]. Ecology and Environmental Sciences, 2021, 30(4):841-848.
State Administration for Market Supervision and Administration, Ministry of Ecology and Environment.GB 15618—2018 Soil environmental quality standard for soil pollution risk control of agricultural land (Trial) [S]. Beijing: China Environmental Science Press, 2018.
Yang A, Wang Y H, Hu J, et al. Evaluation and source of heavy metal pollution in surface soil of Qinghai-Tibet Plateau[J]. Environmental Science, 2020, 41(2):886-894.
[23]
Paatero P, Tapper U. Positive matrix factorization:A non-negative factor model with optimal utilization of error estimates of data values[J]. Environmetrics, 1994, 5(2):111-126.
Zhang F G, Peng M, Wang H Y, et al. Ecological risk assessment of heavy metals at township scale in the high background of heavy metals,southwestern,China[J]. Environmental Science, 2020, 41(9):4197-4209.
Xia Z S, Bai Y R, Wang Y Q, et al. Spatial distribution and source analysis of soil heavy metals in a small watershed in the mountainous area of southern Ningxia based on PMF model[J]. Environmental Science, 2022, 43(1):432-441.
Yin F, Feng K, Yin C J, et al. Evaluation and source analysis of heavy metal in cultivated soil around typical industrial district of Qinghai Province[J]. China Environmental Science, 2021, 41(11):5217-5226.
Chai L, Wang X, Ma L, et al. Sources appointment of heavy metals in cultivated soils of Lanzhou based on PMF models[J]. China Environmental Science, 2020, 40(9):3919-3929.
[28]
USEPA. Exposure factors handbook[R]. Washington: National Center for Environmental Assessment, 2011.
[29]
USEPA. Highlights of the child-specific exposure factors handbook(Final Report)[R]. Washington,DC:U.S.Environmental Protection Agency, 2009.
[30]
USEPA. Regional screening level (RSL) for chemical contaminants at superfund sites[R]. Washington,DC:U.S.Environmental Protection Agency, 2013.
Xie T H, Guo J X, Chen Y H, et al. Spatial variability and health risk assessment of heavy metals in soils and crops around the mining area in Fujian Province,China[J]. Journal of Agro-Environment Science, 2019, 38(3):544-554.
Bao L R, Deng H, Jia Z M, et al. Ecological and health risk assessment of heavy metals in farmland soil of northwest Xiushan,Chongqing[J]. Geology in China, 2020, 47(6):1625-1636.
[33]
中国环境监测总站. 中国土壤元素背景值[M]. 北京: 中国环境科学出版社,1990.
[33]
China Environmental Monitoring Station. Background values of soil elements in China[M]. Beijing: China Environmental Science Press,1990.
Jiang Y L, Yu J, Wang R, et al. Source analysis and pollution assessment of soil heavy metals in typical geological high background area in southeastern Chongqing[J]. Environmental Science, 2023, 44(7):4017-4026.
Wang R, Deng H, Yan M S, et al. Assessment and source analysis of heavy metal pollution in farmland soils in southern Youyang County,Chongqing[J]. Environmental Science, 2020, 41(10):4749-4756.
Huo M Z, Gao B B, Qiao D Y, et al. Source apportionment of heavy metals in farmland soil based on the APCS-MLR model[J]. Journal of Agro-Environment Science, 2021, 40(5):978-986.
[37]
Cheng G W, Wang M J, Chen Y, et al. Source apportionment of water pollutants in the upstream of Yangtze River using APCS-MLR[J]. Environmental Geochemistry and Health, 2020, 42(11):3795-3810.
Ma H H, Peng M, Liu F, et al. Bioavailability,translocation,and accumulation characteristic of heavy metals in a soil-crop system from a typical carbonate rock area in Guangxi,China[J]. Environmental Science, 2020, 41(1):449-459.
Yu F, Wang J B, Wang R, et al. Source analysis and ecological risk assessment of heavy metals in the arable soil at the geological high background,based on the township scale[J]. Environmental Science, 2023, 44(5):2838-2848.
Chen X D, Lu X W. Source apportionment of soil heavy metals in city residential areas based on the receptor model and geostatistics[J]. Environmental Science, 2017, 38(6):2513-2521.
[41]
Xu Z, Mi W B, Mi N, et al. Characteristics and sources of heavy metal pollution in desert steppe soil related to transportation and industrial activities[J]. Environmental Science and Pollution Research, 2020, 27(31):38835-38848.
Li F, Liu S Y, Li Y, et al. Spatiotemporal variability and source apportionment of soil heavy metals in a industrially developed city[J]. Environmental Science, 2019, 40(2):934-944.
Han L, Xu X B. Quantitative evaluation of human health risk of heavy metals in soils based on positive matrix factorization model and geo-statistics[J]. Environmental Science, 2020, 41(11):5114-5124.
Chen X, Liu H Y, Wu P, et al. Contamination characteristics and source apportionment of heavy metals in tobacco-planting soils in Tongren County based on GIS and PMF methods[J]. Journal of Agro-Environment Science, 2022, 41(4):794-801.
National Health and Family Planning Commission of the People's Republic of China,State Food and Drug Administration. GB 2762—2022 National standard for food safety,limits of contaminants in food[S]. Beijing: Standards Press of China, 2022.
Yang Q, Yang Z F, Zhang Q Z, et al. Ecological risk assessment of Cd and other heavy metals in soil-rice system in high Karst geological background area of Guangxi,China[J]. Scientia Sinica:Terrae, 2021, 51(8):1317-1331.
Li J, Zhan M G, Zhong X Y, et al. Distribution and accumulation of heavy metals in soil-crop systems from a typical carbonate rocks area in Guangxi[J]. Acta Scientiae Circumstantiae, 2021, 41(2):597-606.
Guo C, Wen Y B, Yang Z F, et al. Factors controlling the bioavailability of soil cadmium in typical Karst areas with high geogenic background[J]. Journal of Nanjing University:Natural Science, 2019, 55(4):678-687.