Health Risk Assessment on Rural Drinking Water Safety —A Case Study in Rain City District of Ya’an City of Sichuan Province

Taking Rain City District of Ya’an for example, this paper based on ComGIS (Component Object Model Geographic Information System) platform takes comprehensive and systematic detection on the exposure dose of chemical carcinogens and non-carcinogens from drinking water sources in this region and discusses health risk assessment of single factor and the whole health risk assessment. As, Hg, Cr, Pb, Cd and fluorides in some drinking water sources of Rain City District are analyzed according to Standards For Drinking Wa-ter Quality (GB5749-2006). A health risk assessment model called USEPA is also applied to drinking water health risk assessment and management countermeasure is proposed. The results show that the greatest health risk for individual person per year is caused by Cr(VI). The health risk of carcinogens is much higher than that of non-carcinogens: the greatest risk value due to non-carcinogen pollutants is caused by fluoride (F), achieving 1.05×10-8/a. The ranking of risk values due to non-carcinogen pollutants by drinking water is Pb>fluoride (F)>Hg, within Pb accounting for 44.77%, fluo-ride (F) accounting for 34.30% and Hg accounting for 20.92%. The average individual carcinogenesis annual risk of Cr(VI) is the greatest, achieving 8.91×10-4/a. The ranking of risk value due to chemical carcinogen by rural drinking water of Ya’an is Cr6+>As>Cd, within Cr6+ accounting for 91.12%, As accounting for 5.89% and Cd accounting for 3.00%. Based on this, the strategy and measures of the health risk management are put forward. This study has worked efficiently in practice. Compared with the same kind of methods which have been found, the paper has the outstanding results for the health risk assessment of the rural drinking water safety.

Potentially toxic metal concentration,spatial distribution,and health risk assessment in drinking groundwater resources of southeast Iran

In this study, the concentration and spatial distribution of potentially toxic metals(PTMs), including arsenic(As), cadmium(Cd), chromium(Cr), lead(Pb), copper(Cu), iron(Fe), manganese(Mn), and magnesium(Mg) in 23 wells and drinking groundwater distribution networks of Rafsanjan, located in southeast Iran were evaluated. Moreover, the assessment of carcinogenic and non-carcinogenic risks was estimated by Monte Carlo simulation(MCS). The results showed that the concentrations of As and Pb in more than 99% and 23.46% of the study area, respectively, were higher than the maximum concentration level(10 μg/L). The mean concentration of other metals, including Cd, Cr, Cu, Fe, Mg, and Mn in all drinking water resources was within the WHO standard level. The mean hazard quotient(HQ) for As in the age group of children was 9.246 and adults 2.972, indicating high non-carcinogenic risk of As in the study area. The lifetime cancer risk(LTCR) of As was 1.36 E-3 for adults and 1.52 E-2 for children, indicating high non-carcinogenic risk of As. The level of HQ and LTCR for Pb in both age groups was in the acceptable range. The results of sensitivity analysis showed that the most effective variables were pollutant concentration and body weight(BW), respectively. Finally, it can be concluded that exposure to PTMs, especially As through drinking water in the study area can have significant effects on people’s health living in the area;therefore, it is necessary to treat and remove As from groundwater resources before drinking or using for domestic purpose.

Migration of Heavy Metal Elements in Reclaimed Irrigation Water-Soil-Plant System and Potential Risk to Human Health

[Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods]Taking Zhongwei City in Ningxia,a typical arid area,as the research area,the irrigation water,soil and green grass in the reclaimed water irrigation region and the original green water irrigation region were sampled,the heavy elements Hg,As,Zn,Pb,Cd,Cr were detected,and the Nemerow method,biological absorption coefficient,and health risk assessment were employed to evaluate the degree of soil pollution,plant absorption capacity,and human health risks.[Results]Compared with the original green water,the Hg,Cd,and Cr pollution of the reclaimed water irrigated green land was higher,the As,Zn,Pb pollution was lower,and the content of Hg and Cd was higher than the environmental background values of soil in Ningxia;the Cr content exceeded the risk intervention values of the first type of land in the Soil Environmental Quality—Risk Control Standard for Soil Contamination of Development Land(GB 36600-2018).Compared with the original green water irrigation region,it is found that the reclaimed water irrigation reduced the heavy metal pollution of the soil to a certain extent.The heavy metal content of tall fescue grass(Festuca arundinacea)in the reclaimed water irrigation region was Zn,Cr,Pb,As,Cd,and Hg from high to low;the order of the biological absorption coefficient was Cd>As>Zn>Pb>Hg>Cr;irrigation water exerted a certain effect on the content of heavy metals in plants and the biological absorption coefficient through the soil.Using the health risk assessment method recommended by Environmental Protection Agency of the United States of America(USEPA),it was found that the reclaimed water has the highest risk through the inhalation route,and the occupational population has a higher risk of skin contact with soil and plants.[Conclusions]This study is intended to provide data support and theoretical basis for the environmental safety risk research of the application of reclaimed water in arid areas to urban greening.

Surface water quality and potential health risk assessments in Changsha-Zhuzhou-Xiangtan section of Xiangjiang River, China

The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water quality parameters including pH,dissolved oxygen(DO),Escherichia coli(E.coli),potassium permanganate index(CODMn),dichromate oxidizability(CODCr),five-day biochemical oxygen demand(BOD5),ammonia nitrogen(NH4+-N),total nitrogen(TN),total phosphorus(TP)and fluoride(F)in 18 sampling sites of the Changsha-Xiangtan-Zhuzhou section are monthly monitored in 2016,which is the year to step into the second stage of the“Xiangjiang River Heavy Metal Pollution Control Implementation Plan”.It is found that E.coli,TN and TP are the main pollutants in the Changsha-Zhuzhou-Xiangtan section,and the pollution of heavy metal is not serious but As with potential risk to local people especially children should be concerned.In addition,Xiangtan city is mainly featured with heavy metal pollution,while Zhuzhou and Changsha city are both featured with other pollutants from municipal domestic sewage.

Human health ambient water quality criteria for 13 heavy metals and health risk assessment in Taihu Lake

Heavy metals are widely concerning because of their toxicity,persistence,non-degradation and bioaccumulation ability.Iluman health ambient water quality criteria(AWQC)are specific levels of chemicals that can occur in water without harming human health.At present,most countries do not consider the effects of aquatic vegetables in deriving human health AWQC.Therefore,the intake of aquatic vegetables(Brasenia schreberi)was added to the derivation of human health AWQC and a health risk assessment for 13 heavy metals in Taihu Lake.The human health AWQC(consumption of water,fish and aquatic vegetables)values of 13 heavy metals ranged from 0.04(Cd)to 710.87μg/L(Sn),and the intake of B.schreberi had a very significant effect on the human health AWQC for Cu,with a more than 62-fold difference.The hazard quotients of As(2.8),Cd(1.6),Cr(1.4)and Cu(4.86)were higher than the safe level(HQ=1),indicating that As,Cd,Cr and Cu in Taihu Lake posed a significant health risk.Sensitivity analysis showed that the contribution rate of B.schreberi intake to the human health risk from Cu was 91.6%,and all results indicated that the risk of Cu in B.schreberi to human health should be of particular concern.This study adds the consideration of aquatic vegetable consumption to the traditional method of human health AWQC derivation and risk assessments for the first time,and this approach can promote the development of risk assessments and water quality criteria.

Drinking water quality & health risk assessment of secondary water supply systems in residential neighborhoods

Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water safety.SWSSs are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase risks.In this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential neighborhoods.In total,121 seasonal water samples were selected.It was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial count.The HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and adults.However,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major substance.Summer samples had poor water quality and higher health risks,which called for attention.To further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during summer.All 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent quality.Their HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in May.Overall,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.

Health risks associated with heavy metals in the drinking water of Swat,northern Pakistan

The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources （surface and groundwater） collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake （CDI） and health risk index （HRI） were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr 〉 Mn 〉 Ni 〉 Zn 〉 Cd 〉 Cu 〉 Pb and Cd 〉 Ni 〉 Mn 〉 Cr 〉 Cu 〉 Pb 〉 Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.

Indices of Water Quality and Pesticide Monitoring Survey in Lake of Western Cote d’Ivoire and Its Human Risk Assessment

The aims of the work were to study the current quality of the water in Lake DOHOU used for drinking water supply through several physical, chemical analyses and using water quality indices (WQI). In addition, the question was whether the populations are at risk after drinking water of lake following a reduction of 50% and 75% in the median and maximum values of pesticides. Thus, the results of the pesticide monitoring program were incorporated into probabilistic human health risk assessment exercises. Water samples were collected over a period of one year. Pesticides were subjected to solid phase extraction and then analyzed using gas chromatography coupled to tandem mass spectroscopy. The other parameters were measured according to conventional methods. The results showed that the most frequently detected pesticides were aldicarb (79%), simazine (79%) and monolinuron (44%). They also showed the mean values of concentrations exceeding 1.5 μg/L. Metoxuron detected at a frequency of 29% showed the maximum average concentration (13.46 μg/L). Nearly 98% of the sampling points had at least one substance with an average concentration above the quality standard (0.1 μg/L) and 80% did not meet the total concentration standards. Cumulative risk quotient estimates after 50% or 75% abatement for frequently identified pesticides were greater than unity when extreme?values for adults and children were considered. To determine the suitability of water for aquatic life, drinking water consumption and drinking water production, the water quality index (WQI), the heavy metal pollution (HPI) and the heavy metal evaluation (HEI) were calculated. The poor quality of the water was mainly related to pesticides, organic matter and microbiological parameters. Most of the nutrients and metals studied were often below the standards of drinking water and aquatic life. The Water Quality Index (WQI) has shown that water quality is degrading for these three modes of use and ranges from poor to marginal. The coupling of monitoring data with probabilistic estimates of human risks could be used by the Ivorian authorities to propose effective pollution management plans.

甘肃省白银市四龙镇—北湾镇耕地区土壤重金属现状及生态风险评价

[研究目的]甘肃省白银地区矿业发达,矿山开采导致土壤重金属污染严重,掌握当地土壤重金属污染及对生态健康风险的影响对生态环境保护具有重要意义。[研究方法]以甘肃省白银地区四龙镇一北湾镇耕地区表层土壤为研究对象,采用单因子指数法、内梅罗综合指数法、地积累指数法和潜在生态危害指数法四种方法对区内表层土壤重金属(As、Cd、Cr、Cu、Hg、Ni、Pb、Zn)污染进行了分析和评价。[研究结果]单因子指数法统计结果显示研究区土壤污染主要为Cd、As的污染,单因子指数PCd显示89.21%的土壤为一等清洁,8.63%为二等轻微污染,0.72%为三等轻度污染,1.44%为四等中度污染。单因子指数PAs显示94.24%为土壤为一等清洁,5.04%为二等轻微污染,0.72%四等中度污染。内梅罗综合指数Pz介于0.339~2.869,均值为0.603;Pz显示85.61%的土壤为清洁,7.91%为轻微污染,5.04%为轻度污染,1.44%为中度污染。地积累指数法结果显示研究区土壤重金属污染总体处于0~2级,以Cd、Hg、As、Pb污染为主。潜在生态危害指数法结果显示,研究区污染以Cd、Hg污染为主;Cd潜在生态风险最大,10.07%属于中潜在风险,5.04%属于较高潜在风险,1.44%属于很高潜在风险;潜在生态危害综合指数平均值为211.80,表明该地区土壤总体处于中等危害程度。四种方法评价结果总体一致,即研究区以Cd、As、Hg污染为主,应加强监测。[结论]以黄河为界对调查区进行分区研究,结果显示北岸灌淤土区(B区)污染最为严重,与东大沟河交界位置污染程度最高,水体及底泥样品重金属分析结果也证实东大沟河污染也较为明显,进一步证实了研究区北部主要受白银矿山东大沟河流域污染为主,而黄河南岸土壤相对清洁,但也受到不同程度的影响。近些年,随着引黄灌溉及矿山环境治理等措施,土壤污染有所缓解,但土壤中累积的重金属需要长时间的自然降解或迁移,对高风险区仍应加强监测及治理。

豫西钼矿集区地表水重金属时空分布特征及健康风险评价

豫西钼矿集区内长期的矿产资源开发向周围环境释放大量的重金属,区内地表水环境质量现状尚不明晰。于2019年丰水期(8月)和枯水期(12月)对矿集区内5条河流进行地表水采集,调查地表水重金属(Mo、Cd、Hg、As、Cr、Cu、Pb、Zn)的时空分布特征,并用健康风险模型评价地表水重金属人体健康风险。结果表明,丰水期地表水主要污染元素为Mo、Zn和Cd,而枯水期地表水主要污染元素为Mo、Hg和Cd,大多数点位地表水符合II类标准。地表水中的Mo主要来源于钼矿;Pb和Zn主要来源于钼矿和铅锌矿;Cd主要源于金矿和铅锌矿;Hg主要源于金矿。健康风险评价结果表明,地表水重金属通过饮用水途径所致的总个人年健康风险均低于美国环保署(US EPA)推荐的最大可接受风险水平。除丰水期成人总个人年健康风险低于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平外,丰水期儿童、枯水期成人和儿童高于ICRP推荐的最大可接受风险水平。研究的结果可为钼矿集区地表水污染防治和风险管控提供科学依据。

2017-2022年陕西省某市农村生活饮用水中5种金属及类金属健康风险

目的评估2017-2022年陕西省某市农村生活饮用水中砷(As)、镉(Cd)、铬(VI,Cr^(6+))、铅(Pb)及汞(Hg)5种金属及类金属的健康风险。方法分析陕西省某市2017-2022年间4153份农村生活饮用水监测数据,应用美国环境保护局(US EPA)推荐的健康风险评估模型计算不同暴露水平下不同暴露水平下5种金属及类金属经饮水途径对当地居民所致的健康风险。结果陕西省某市2017-2022年农村饮用水中5种金属及类金属在一般暴露水平下经饮水途径所致的总危害指数(HI)为0.344,总致癌风险(R_(T))为3.99×10^(-4);高暴露水平下经饮水途径所致的HI为1.81,R_(T)为1.99×10^(-3)。浓度分层分析表明Cd、Cr^(6+)和Hg的浓度在枯水期均高于丰水期;江河水中As、Cd、Cr^(6+)和Pb的浓度均高于其他类型水源水,浅井水中Hg的浓度较高;部分处理水样中5种金属及类金属的浓度均高于未处理和完全处理水样。健康风险分层分析表明,经饮水途径摄入5种金属及类金属,男性的健康风险高于女性、儿童高于成人。结论陕西省某市2017-2022年农村饮用水中5种金属及类金属一般暴露水平下的非致癌风险及总危害指数均未超过可接受风险值,高暴露水平下总危害指数超出可接受风险值;Cr^(6+)无论是一般暴露水平还是高暴露水平,其致癌风险均略高于最大可接受风险(10^(-6)~10^(-4)),在风险管理中应重点关注。

某饮用水源地水体重金属分布特征及健康风险评价

为探讨湖库型饮用水源地水体重金属的分布特征及引起的人体健康风险,以云南中部某水库饮用水源地水体为研究对象,基于当地生态环境监测部门2019—2021年水质监测数据,分析了研究区库区和入库河流水体中8种重金属Zn、Pb、Fe、Cd、Mn、Cr6+、As、Hg的质量浓度和分布特征,并运用美国环境保护署(US EPA)推荐的健康风险评价模型进行人体健康风险评价。结果表明:2019—2021年研究区库区和入库河流水体中均未检出Hg、Cr6+、Pb和Cd,但Zn、As、Fe和Mn均有不同程度检出,且检出质量浓度高值集中在入库河流,入库河流水体重金属质量浓度高值出现在丰水期,库区重金属质量浓度高值出现在枯水期,其中Fe、Mn质量浓度最大值超过我国《生活饮用水卫生标准》(GB 5749—2022)和《地表水环境质量标准》(GB 3838—2002)Ⅲ类水标准限值;经饮水途径,非致癌重金属Pb、Hg、Zn、Fe和Mn对成人和儿童的年健康风险均值处于10-10/a水平,为无风险;致癌重金属As、Cd和Cr6+对成人的最大年健康风险接近国际辐射防护委员会(ICRP)推荐限值,需引起高度重视,而对儿童的最大年健康风险已超过ICRP推荐限值,有致癌风险;致癌重金属Cr6+和As为儿童致癌风险的决定元素,在儿童饮水方面应优先管控。

鄱阳湖周边水体重金属污染特征及人体健康风险评价

为分析鄱阳湖周边水体重金属污染特征及人体健康风险,于鄱阳湖周边采集18个地表水水样,对水体中重金属的来源及分布进行分析,并根据美国环保局(USEPA)的风险评价模型评价水体中重金属对人体的健康风险。研究区水体主要阳离子为Ca^(2+),阴离子为HCO_(3)^(-)、SO_(4)^(2-)与Cl^(-)。水化学成因主要为岩石风化及矿物水解,部分受大气降水作用控制。地表水中重金属元素平均浓度为Fe>Ba>Mn>Mo>Zn>Cu>Ni>Pb。Fe、Mo、Ni、Mn均有不同程度的超标现象,其主要来源于肥料施放、工厂排放等活动。Mo对儿童和成人的HQ der、HI>1,Ba对儿童的HQ der、HI>1,对人体健康会造成较大危害。研究可为鄱阳湖周边水资源保护提供科学依据。

珠海西部地区集中式饮用水源地重金属含量特征及健康风险评价

根据2023年珠海市西部地区11个饮用水源地的重金属监测数据资料,基于中国人群暴露参数,应用美国环保局(USEPA)推荐的健康风险评价模型,对珠海西部地区10项重金属开展了当地居民的健康风险评价。结果表明:1)珠海西部地区饮用水源中10项重金属年均值均达到《地表水环境质量标准》(GB 3838—2002)Ⅰ类和《生活饮用水标准》(GB 5749—2022)标准限值要求。2)儿童和成人的总健康风险均值分别为4.39×10^(-5)和4.23×10^(-5)a^(-1),均在国际放射防护委员会(ICRP)推荐的最大可接受水平阈值(5×10^(-5))内,但儿童总健康风险比成人略高。3)重金属类致癌污染物风险远大于非致癌污染物健康风险,六价铬是研究区域内重金属污染风险管控的主要对象。

2021-2023年胶东沿海某地区农村饮用水氟化物监测分析与健康风险评价

目的:通过对胶东沿海某地区2021-2023年农村饮用水氟化物浓度进行监测分析,了解当地农村饮用水水质情况,评估饮用水中氟化物对人体的健康风险。方法:采用《生活饮用水标准检验方法无机非金属指标》(GB/T 5750.5-2006)中离子色谱法进行饮用水中氟化物测定,根据《生活饮用水卫生标准》(GB 5749-2006)及US EPA所提出的环境卫生危险性评估模型对检测结论进行评估。结果:2021-2023年共检测农村饮用水水样1695份,1629份合格,合格率为96.11%。3年间氟化物含量差异有统计学意义(F=3.988,p<0.05)。2021-2023年水中氟化物对成人和儿童的健康风险值分别为2.38×10^(-9) a^(-1)和4.76×10^(-9) a^(-1),2.78×10^(-9) a^(-1)和5.55×10^(-9) a^(-1),3.27×10^(-9) a^(-1)和6.54×10^(-9) a^(-1),所有水样的健康风险值均小于1.0×10^(-5) a^(-1)。结论:该地区农村饮用水中氟化物浓度总体较低,合格率较高。对于健康风险而言,地下水高于地表水、分散式供水高于集中式供水、儿童高于成人。总体来讲,该地区处于低风险范围。

北京市饮用水源水重金属污染物健康风险的初步评价

对北京市城区 8个区和郊区 10个区、县 12 0个样点的饮用水中Cu ,Hg ,Cd和As的浓度进行了调查研究 ,并应用目前美国环保局推荐的健康风险评价模型对北京市各区县饮用水中重金属所引起的健康风险作了初步评价 .结果表明 ,城区 8个区和郊区 10个区、县重金属的平均浓度范围分别为Cu :0 81～ 6 96 μg·L-1,Cd :0 34～ 0 82 μg·L-1,Hg :0 10～ 0 74μg·L-1,As:0 19～ 3 0 2 μg·L-1.通过饮水途径所致健康风险中 ,As在通州区所引起的致癌风险最大 ( 2 0× 10 -5·a-1) ,Cd在昌平区的致癌风险最大 ( 2 3× 10 -6·a-1) ,但均低于国际辐射防护委员会 (ICRP)推荐的通过饮水途径最大可接受风险水平( 5× 10 -5·a-1) ;在北京市通过饮水途径引起的非致癌健康风险中 ,Hg的风险最大 ,Cu次之 ,但是两者风险水平均在 10 -8～10 -9·a-1,远低于ICRP推荐的最大可接受风险水平 .

上海市主要饮用水源地水重金属健康风险初步评价

对上海市主要饮用水源地(黄浦江上游地区和陈行水库)水中重金属含量进行了调查研究,并应用水环境健康风险评价模型对其进行健康风险的初步评价.结果表明,黄浦江上游和陈行水库由致癌物质Cr,As,Cd通过饮水途径引起的个人年健康风险平均值分别表现为Cr>As>Cd和As>Cr>Cd,风险值为10-7～10-5a-1,Cr和As的风险值高于部分机构推荐的最大可接受风险水平(1×10-6a-1),而低于国际放射防护委员会(ICRP)和美国环境保护署(USEPA)的推荐值(5×10-5和1×10-4a-1),成为上海市饮用水源地主要的致癌因子;黄浦江上游和陈行水库由非致癌物质Pb,Cu,Zn,Hg导致的个人年健康风险平均值分别表现为Pb>Cu>Zn>Hg和Hg>Cu>Pb>Zn,风险值为10-12～10-10a-1.各采样点重金属类致癌物质的风险值明显高于非致癌物质.

环鄱阳湖区农村饮用水重金属健康风险评价

运用目前美国环保局推荐的健康风险评价模型对环鄱阳湖区农村饮用水中重金属所引起的健康风险作了初步评价．结果表明：沙湖长古村、赣江中支、滁槎的Pb含量超过GB5749---2006（（生活饮用水卫生标准》，应引起高度重视；通过饮水途径所致健康风险中，非致癌物和致癌物所致风险都远低于国际辐射防护委员会（ICRP）推荐的最大可接受风险水平（5×10^-5·a^-1），其中非致癌物引起的个人年均风险Zn〉Pb〉Cu，致癌物cd所致风险大于非致癌物，占总风险度的70．65％～96．04％，表明Cd是产生风险的主要污染物，因此，应优先考虑防治致癌物Cd对农村饮用水的污染．

ICP-MS在水库水源地重金属污染健康风险评价中的应用

对辽河流域水库饮用水源地水样中重金属元素（Cr ，As ，Cd ，Cu ，Zn和Pb）浓度进行了调查研究，并采用美国环保署推荐的健康风险评价模型对水库中重金属污染做了初步的健康风险评价。结果表明，辽河流域5个水库中6种重金属元素Cr ，Cu ，Zn ，As ，Cd和Pb的平均浓度分别为3.36，1.03，2.70，1.23，0.02，0.03μg · L -1，均未超过国家生活饮用水卫生标准（GB 5749-2006）。健康风险评价结果表明，研究区域的金属致癌风险较高，致癌重金属的健康风险大小依次为Cr＞As＞Cd。其中，水库中Cr元素致癌风险最高，成人和儿童分别为4.50×10-5～7.53×10-5和6.29×10-5～1.05×10-4 a-1。非致癌重金属引起的健康风险值为10-13～10-10 a-1，均在国际辐射防护委员会（ICRP）所规定的可接受范围内，健康风险大小为Cu＞Zn＞Pb。重金属总健康风险成人为1.07×10-4～1.72×10-4 a-1，儿童为1.49×10-4～2.40×10-4 a-1，均超过ICRP推荐的5×10-5 a-1。辽河流域饮用水源地致癌重金属的风险明显高于非致癌重金属。

保定市区生活饮用水中重金属污染物健康风险初步评价

以保定市3个市区的居民生活饮用水为研究对象,对其中Mn、Cu、Zn、As、Cd、Hg、Pb等重金属离子的含量进行了调查研究,并采用我国《生活饮用水卫生标准》(GB5749—2006)和目前美国环保署(EPA)推荐的健康风险评价模型对各市区饮用水中重金属所引起的健康风险进行了初步评价.结果表明,保定市各市区饮用水中重金属平均浓度范围分别为Mn:5.31—13.7μg·L-1,Cu:3.24—7.46μg·L-1,Zn:96.3—107μg·L-1,As:0.72—0.78μg·L-1,Cd:0.03—0.05μg·L-1,Hg:1.69—1.79μg·L-1,Pb:0.26—1.16μg·L-1,均未超出《生活饮用水卫生标准》.通过饮水途径所致健康风险中,As在北市区所引起的致癌风险最大(5.3×10-6a-1),Cd在新市区的致癌风险最大(1.4×10-7a-1),但均低于国际辐射防护委员会(ICRP)推荐的通过饮水途径最大可接受风险水平(5.0×10-5a-1);在保定市通过饮水途径引起的非致癌健康风险中,Zn的风险最大,Hg次之,但两者风险水平均在10-6—10-8之间,也低于ICRP推荐的最大可接受水平.此外,研究还表明大部分给水管材及其使用年限对水中重金属浓度影响不大.