-
水是一切生命之源,是地球上一切生命赖以生存和发展的必要因素。近年来,随着城镇化、工业化进程日益加快,各种环境地质问题也随之而来,特别是地表水和地下水污染问题日益突出[1-3]。一个地区水的各种元素含量和赋存形态直接影响到当地水质的好坏,决定着当地水环境的质量,关系到当地居民的饮用水健康。查明一个地区地表水和地下水水化学组分浓度和赋存形态可更好的了解区域地表水与地下水的演化规律,揭示水环境现状与人类活动的相互作用机制,对于促进人类健康饮水和区域生态环境保护具有重大意义[4-9]。饮用水硝酸盐(
${\rm{NO}}_3^- $ )污染是世界性的环境问题,长期饮用会诱发高铁血红蛋白症、蓝婴综合症及癌症等疾病,严重威胁人类健康[10-11],因此,需通过水质健康风险评价来确定硝酸盐污染对人体的危害。钦州市钦南区地处广西壮族自治区南部沿海中段,是广西与东盟联系的“桥头堡”和北部湾(广西)经济区水陆交通枢纽,区内及钦州地区水化学、水质的相关研究较少。何军等[12]对北部湾主要环境地质问题研究发现地下水污染组分主要为氨氮和硝酸盐;陈雯等[13]只对钦州港地下水化学类型和不同季节变化进行研究。但对于钦南区水化学特征的总体研究及评价还存在空白,饮用水硝酸盐对该地区居民健康的影响也需进一步评价。本文通过对该区的地表水和地下水进行系统采样,测试其化学组分浓度及其它指标,分析地表水和地下水的水化学特征,揭示研究区地表水和地下水水化学类型和联系,并对区内水质进行评价、对区内饮用水硝酸盐污染进行健康风险评价,为区域水资源可持续开发利用及环境保护政策的制定提供参考。
钦州钦南区水化学特征及健康风险评价
Hydrochemical characteristics and water quality evaluation of Qinnan District, Qinzhou City
-
摘要: 为探究钦南区水化学特征及质量时空分布规律,评价超标元素对人体的健康风险,2020年9月系统采集水样54件进行分析测试,利用数理统计、Piper三线图、Gibbs图、离子比值法研究其水化学类型及分布特征,利用钠吸附比(SAR)和钠百分比(SSP)指标开展灌溉水评价,利用单因子评价法和内梅罗指数法开展饮用水水质评价,利用健康风险模型对不同人群进行健康风险评价。结果表明,钦江水系属HCO3-Na·Ca型,大风江水系属HCO3·Cl-Na·Ca型,水库水化学类型主要为HCO3-Na·Ca型和HCO3·Cl-Na·Ca型,地下水化学类型主要为HCO3-Na·Ca型、HCO3-Ca型和HCO3·Cl-Na·Ca型,研究区水化学成分主要受岩石风化和大气降水作用的影响,区内河流和水库均适用于灌溉。单因子评价和内梅罗综合指数法显示研究区水质整体较好,部分样品超标组分主要为
${\rm{NO}}_3^- $ 。硝酸盐的健康风险评价模型显示1个样品(井水)因家禽养殖健康风险超标,且饮水途径风险高于暴露途径风险,考虑其对儿童影响较大,建议饮用水经除硝处理后使用。Abstract: In order to explore the hydrochemical characteristics and temporal and spatial distribution law of quality in Qinnan District, and evaluate the health risk of excessive elements to human body, 54 water samples were systematically collected for analysis and testing in September 2020. The hydrochemical types and distribution characteristics were studied by using mathematical statistics, Piper trilinear diagram, Gibbs diagram and ion ratio method, and the irrigation water was evaluated by using sodium adsorption ratio (SAR) and sodium percentage (SSP), The single factor evaluation method and Nemero index method were used to evaluate the drinking water quality, and the health risk model was used to evaluate the health risk of different populations. The results show that Qinjiang River system belongs to HCO3-Na·Ca, Dafengjiang river system belongs to HCO3·Cl-Na·Ca, reservoir hydrochemical types are mainly HCO3-Na·Ca and HCO3·Cl-Na·Ca, groundwater chemical types are mainly HCO3-Na·Ca , HCO3-Ca and HCO3·Cl-Na·Ca. The Hydrochemical Composition of the study area is mainly affected by rock weathering and atmospheric precipitation, The rivers and reservoirs in the area are suitable for irrigation. Single factor evaluation and Nemero comprehensive index method show that the overall water quality in the study area is good, and the exceeding standard components of some samples are mainly${\rm{NO}}_3^- $ . The health risk assessment model of nitrate shows that one sample (well water) exceeds the standard due to the health risk of poultry breeding, and the risk of drinking water is higher than that of exposure. Considering its great impact on children, it is recommended to use drinking water after denitration treatment. -
表 1 水质单项组分评分
Table 1. Single component score of water quality
类别 Category Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ Fi 0 1 3 6 10 表 2 水质量分级
Table 2. Water quality classification
级别
Level优良
Excellent良好
Good一般
Commonly较差
Bad极差
Very badF <0.8 0.82.5 2.5—4.25 4.25—7.2 >7.2 表 3 健康风险评价模型参数
Table 3. Parameters employed for human health risk assessment
符号
Symbol参数名称
Parameter name单位
Unit儿童
Children男性
Man女性
WomenDRf 硝酸盐参考剂量 mg·(kg·d)−1 1.6 1.6 1.6 IR 饮水率 L·d−1 1.8 2 2 BW 居民平均体重 kg 30 65 50 ET 洗澡时间 h·d−1 0.3 0.2 0.5 ABS 胃肠吸收系数 无量纲 0.5 0.5 0.5 AT 平均接触时间 d 365×ED 365×ED 365×ED EV 洗澡频率 无量纲 1.5 2 1 KP 皮肤渗透系数 cm·h−1 0.001 0.001 0.001 CF 体积转换因子 L·cm−1 0.001 0.001 0.001 ED 暴露持续时间 a 12 30 30 EF 暴露频率 d·a−1 365 365 365 SA 皮肤接触面积 cm2 1.2×104 1.6×104 1.5×104 表 4 研究区水化学参数统计
Table 4. Descriptive statistics for the chemical analysis of groundwater samples
指标
Index统计量
StatisticpH TDS TH EC Fe Ca2+ Mg2+ K+ Na+ ${\rm{NH}}_4^+ $ ${\rm{HCO}}_3^-$ ${\rm{ SO}}_4^{2-}$ ${\rm{NO}}_3^-$ Cl− 河流
River最大值 Maximum 7.31 138 77 290 0.92 24.5 3.6 5.13 10.6 0.38 75.33 20.2 21.3 13.5 最小值 Minimum 6.6 14 15.6 136 0.07 3.65 1.3 1.71 2.45 0.01 15.07 1.51 2.44 3.92 平均值 Average 6.92 80.14 40.9 176.85 0.5 12.42 2.25 3.16 5.39 0.15 38 10 14.86 9.48 标准差
Standard Deviation0.28 40.03 22.47 49.77 0.37 7.45 0.9 1.45 2.93 0.15 20.1 7.04 7.68 3.41 变异系数
Coefficient of variation0.04 0.5 0.55 0.28 0.74 0.6 0.4 0.46 0.54 1 0.53 0.7 0.52 0.36 水库
Reservoir最大值 Maximum 8.5 279 150 982 0.41 49.4 6.34 9.72 42 1.63 134.42 32.7 13.6 50.3 最小值 Minimum 4.26 2 6.27 176 0.01 1.45 0.63 0.8 1.47 0.01 2.9 0.96 1.93 2 平均值 Average 6.73 75.71 45.6 406.82 0.09 13.86 2.52 3.39 7.72 0.45 41.2 6.32 7.39 10.13 标准差
Standard Deviation1.1 80 48.1 211.04 0.11 15.96 2 2.55 11.4 0.58 37.44 8.72 3.55 13.46 变异系数
Coefficient of variation0.16 1.06 1.05 0.52 1.22 1.15 0.79 0.75 1.48 1.29 0.9 1.38 0.48 1.33 地下水
Groundwater最大值 Maximum 7.7 806 245 626 0.82 85.1 31.5 38.8 65.2 0.64 238.61 82.1 162.49 56.4 最小值 Minimum 4.32 4 6.3 31 0.01 1.45 0.47 0.37 1.23 0.01 2 0.5 0.07 8.11 平均值 Average 6.39 149.1 79.2 221.32 0.15 22.73 5.16 4.43 16.86 0.08 67.49 14.21 18.21 14.68 标准差
Standard Deviation0.66 152.7 61.9 154.35 0.19 18.48 5.9 7.56 16.64 0.12 61.09 19.57 26.99 14 变异系数
Coefficient of variation0.1 1.02 0.78 0.7 1.27 0.81 1.14 1.7 0.99 1.5 0.9 1.38 1.48 0.95 EC单位:μs·cm−1;pH、变异系数无单位,其它均为mg·L−1.
EC unit : μs·cm−1;pH and coefficient of variation have no unit , others are mg·L−1.表 5 硝酸盐在不同暴露途径下的非致癌风险
Table 5. Non-carcinogenic risk of nitrate in drinking water and Dermal contact pathway
人群
Crowd饮水摄入风险指数
Drinking water intake risk index皮肤接触风险指数
Skin exposure risk index两种暴露途径总风险
Total risk of two exposure routes范围
Range平均值
Average范围
Range平均值
Average范围
Range平均值
Average儿童
Children12.93×10−3—3.05 0.35 2.59×10−4—0.061 0.007 0.013—3.11 0.359 成年女性
Woman8.62×10−3—2.03 0.24 1.29×10−4—0.03 0.004 0.009—2.06 0.238 成年男性
Man5.3×10−3—1.25 0.14 1.33×10−4—0.05 0.006 0.006—1.3 0.15 -
[1] 蓝楠, 陈燕, 彭泥泥. 地下水资源保护立法问题研究[M]. 武汉: 中国地质大学出版社, 2010. LAN N, CHEN Y, PENG N N. Research on legislation of groundwater resources protection [M]. Wuhan: China University of Geosciences Press, 2010(in Chinese).
[2] 凌卫宁, 范继辉. 广西水资源近年来变化趋势及可利用水资源潜力分析 [J]. 广西水利水电, 2011(4): 45-48,90. doi: 10.3969/j.issn.1003-1510.2011.04.013 LING W N, FAN J H. Latest change tendency and utilizable potentiality of water resources in Guangxi [J]. Guangxi Water Resources & Hydropower Engineering, 2011(4): 45-48,90(in Chinese). doi: 10.3969/j.issn.1003-1510.2011.04.013
[3] 张岳. 中国水资源与可持续发展[M]. 南宁: 广西科学技术出版社, 2000. ZHANG Y. Water resources and sustainable development in China [M]. Nanning: Guangxi Science and Technology Press, 2000(in Chinese).
[4] 廖柏明. 广西水资源生态保护的法律对策探析 [J]. 社会科学家, 2009(9): 81-84,87. doi: 10.3969/j.issn.1002-3240.2009.09.021 LIAO B M. Analysis of the Legal Countermeasures of Guangxi water resources ecological protection [J]. Social Scientist, 2009(9): 81-84,87(in Chinese). doi: 10.3969/j.issn.1002-3240.2009.09.021
[5] 吴春勇, 苏小四, 郭金淼, 等. 鄂尔多斯沙漠高原白垩系地下水水化学演化的多元统计分析 [J]. 世界地质, 2011, 30(2): 244-253. doi: 10.3969/j.issn.1004-5589.2011.02.013 WU C Y, SU X S, GUO J M, et al. Multivariate statistical analysis of hydrogeochemical evolution of groundwater in Cretaceous aquifer Ordos desert plateau [J]. Global Geology, 2011, 30(2): 244-253(in Chinese). doi: 10.3969/j.issn.1004-5589.2011.02.013
[6] 董维红, 孟莹, 王雨山, 等. 三江平原富锦地区浅层地下水水化学特征及其形成作用 [J]. 吉林大学学报(地球科学版), 2017, 47(2): 542-553. DONG W H, MENG Y, WANG Y S, et al. Hydrochemical characteristics and formation of the shallow groundwater in Fujin, Sanjiang plain [J]. Journal of Jilin University (Earth Science Edition), 2017, 47(2): 542-553(in Chinese).
[7] 陈盟, 吴勇, 高东东, 等. 广汉市平原区浅层地下水化学演化及其控制因素 [J]. 吉林大学学报(地球科学版), 2016, 46(3): 831-843. doi: 10.13278/j.cnki.jjuese.201603205 CHEN M, WU Y, GAO D D, et al. Shallow groundwater hydrogeochemical evolution process and controlling factors in plain zone of Guanghan city [J]. Journal of Jilin University (Earth Science Edition), 2016, 46(3): 831-843(in Chinese). doi: 10.13278/j.cnki.jjuese.201603205
[8] 钟善锦, 曾广庆. 广西地表水污染分析及其保护对策研究 [J]. 环境科学动态, 2003, 28(4): 7-8. ZHONG S J, ZENG G Q. Analysis of surface water pollution in Guangxi and Research on its protection countermeasures [J]. Environmental Science Trends, 2003, 28(4): 7-8(in Chinese).
[9] 范宏喜. 我国地下水资源与环境现状综述 [J]. 水文地质工程地质, 2009, 36(2): 141-143. FAN H X. Overview of groundwater resources and environment in China [J]. Hydrogeology & Engineering Geology, 2009, 36(2): 141-143(in Chinese).
[10] 鲁垠涛, 刘芳, 姚宏, 等. 北京密云水库小流域地下水硝酸盐污染来源示踪 [J]. 环境化学, 2016, 35(1): 180-188. doi: 10.7524/j.issn.0254-6108.2016.01.2015052501 LU Y T, LIU F, YAO H, et al. Source analysis of nitrate pollution source in groundwater in A Small Watershed of Miyun Reservoir in Beijing [J]. Environmental Chemistry, 2016, 35(1): 180-188(in Chinese). doi: 10.7524/j.issn.0254-6108.2016.01.2015052501
[11] GULIS G, CZOMPOLYOVA M, CERHAN J R. An ecologic study of nitrate in municipal drinking water and cancer incidence in trnava district, Slovakia [J]. Environmental Research, 2002, 88(3): 182-187. doi: 10.1006/enrs.2002.4331 [12] 何军, 黎清华, 刘怀庆, 等. 北部湾经济区主要环境地质问题探讨 [J]. 华南地质与矿产, 2015, 31(1): 96-103. doi: 10.3969/j.issn.1007-3701.2015.01.011 HE J, LI Q H, LIU H Q, et al. Review on the main geological environmental problems in Beibu Gulf Economic Zone [J]. Geology and Mineral Resources of South China, 2015, 31(1): 96-103(in Chinese). doi: 10.3969/j.issn.1007-3701.2015.01.011
[13] 陈雯, 黎清华, 刘怀庆, 等. 广西钦州港地区地下水水化学特征及形成作用 [J]. 华南地质与矿产, 2016, 32(1): 78-84. doi: 10.3969/j.issn.1007-3701.2016.01.010 CHEN W, LI Q H, LIU H Q, et al. Analysis on hydrochemical characteristics and formation mechanism of groundwater in Qinzhou Port Area, Guangxi, China [J]. Geology and Mineral Resources of South China, 2016, 32(1): 78-84(in Chinese). doi: 10.3969/j.issn.1007-3701.2016.01.010
[14] SINGH V. Assessment of groundwater quality of parts of Gwalior (India) for agricultural purposes [J]. Indian Journal of Science and Technology, 2008, 1(4): 1-5. [15] AMIRI V, SOHRABI N, DADGAR M A. Evaluation of groundwater chemistry and its suitability for drinking and agricultural uses in the Lenjanat plain, central Iran [J]. Environmental Earth Sciences, 2015, 74(7): 6163-6176. doi: 10.1007/s12665-015-4638-6 [16] 韩智勇, 许模, 刘国, 等. 生活垃圾填埋场地下水污染物识别与质量评价 [J]. 中国环境科学, 2015, 35(9): 2843-2852. doi: 10.3969/j.issn.1000-6923.2015.09.042 HAN Z Y, XU M, LIU G, et al. Pollutant identification and quality assessment of groundwater near municipal solid waste landfills in China [J]. China Environmental Science, 2015, 35(9): 2843-2852(in Chinese). doi: 10.3969/j.issn.1000-6923.2015.09.042
[17] ZHANG J, ZHOU J L, ZHOU Y Z, et al. Hydrogeochemical characteristics and groundwater quality assessment in the plain area of Yarkant River Basin in Xinjiang, P. R. China [J]. Environmental Science and Pollution Research, 2021, 28(24): 31704-31716. doi: 10.1007/s11356-021-12851-8 [18] 关云鹏. 利用内梅罗指数法模型评价地下水水质的探讨 [J]. 山西水利科技, 2012(1): 81-84. doi: 10.3969/j.issn.1006-8139.2012.01.035 GUAN Y P. A discussion on evaluating groundwater quality by nemerow index method [J]. Shanxi Hydrotechnics, 2012(1): 81-84(in Chinese). doi: 10.3969/j.issn.1006-8139.2012.01.035
[19] 杨彦, 于云江, 魏伟伟, 等. 常州市浅层地下水重金属污染对城区、城郊居民健康风险评价 [J]. 环境化学, 2013, 32(2): 202-211. doi: 10.7524/j.issn.0254-6108.2013.02.004 YANG Y, YU Y J, WEI W W, et al. Health risk assessment of heavy metals in shallow groundwater in urban and suburban areas of Changzhou [J]. Environmental Chemistry, 2013, 32(2): 202-211(in Chinese). doi: 10.7524/j.issn.0254-6108.2013.02.004
[20] 杨阳, 许策, 程高峰, 等. 保定市区生活饮用水中重金属污染物健康风险初步评价 [J]. 环境化学, 2014, 33(2): 292-297. doi: 10.7524/j.issn.0254-6108.2014.02.001 YANG Y, XU C, CHENG G F, et al. Preliminary health risk assessment of heavy metals in drinking waters in Baoding City [J]. Environmental Chemistry, 2014, 33(2): 292-297(in Chinese). doi: 10.7524/j.issn.0254-6108.2014.02.001
[21] SINGH C K, KUMAR A, SHASHTRI S, et al. Multivariate statistical analysis and geochemical modeling for geochemical assessment of groundwater of Delhi, India [J]. Journal of Geochemical Exploration, 2017, 175: 59-71. doi: 10.1016/j.gexplo.2017.01.001 [22] GIBBS R J. Mechanisms controlling world water chemistry [J]. Science, 1970, 170(3962): 1088-1090. doi: 10.1126/science.170.3962.1088 [23] 於昊天, 马腾, 邓娅敏, 等. 江汉平原东部地区浅层地下水水化学特征 [J]. 地球科学, 2017, 42(5): 685-692. YU H T, MA T, DENG Y M, et al. Hydrochemical characteristics of shallow groundwater in eastern Jianghan plain [J]. Earth Science, 2017, 42(5): 685-692(in Chinese).
[24] 孙平安, 于奭, 莫付珍, 等. 不同地质背景下河流水化学特征及影响因素研究: 以广西大溶江、灵渠流域为例 [J]. 环境科学, 2016, 37(1): 123-131. SUN P A, YU S, MO F Z, et al. Hydrochemical characteristics and influencing factors in different geological background: A case study in darongjiang and Lingqu basin, Guangxi, China [J]. Environmental Science, 2016, 37(1): 123-131(in Chinese).
[25] CHITSAZAN M, AGHAZADEH N, MIRZAEE Y, et al. Hydrochemical characteristics and quality assessment of urban groundwater in Urmia City, NW Iran [J]. Water Supply, 2017, 17(5): 1410-1425. doi: 10.2166/ws.2017.039 [26] GUO Y L, ZHANG C, XIAO Q, et al. Hydrogeochemical characteristics of a closed Karst groundwater basin in North China [J]. Journal of Radioanalytical and Nuclear Chemistry, 2020, 325(2): 365-379. doi: 10.1007/s10967-020-07247-w