细河流域地下水中持久性有机氯污染物的健康风险评价

为了保障细河流域沿岸居民的生活用水安全,分析了地下水样品中15种持久性有机氯污染物（POCPs）的含量,运用荷兰公共卫生和环境国家研究院提出的土壤地下水污染现场暴露评价（CSOIL）模型对持久性有机氯污染物的健康风险进行了初步评价。结果表明：细河流域各采样点地下水中∑PCBs含量为0.08～5.89ng/L,∑OCPs含量为0.17～21.2ng/L,均低于各自生活饮用水卫生标准（GB5749-2006）中的浓度限值。作物食入、饮水等经口摄入途径是地下水环境健康风险评价中最主要的暴露途径,各采样点地下水中POCPs由作物食入、饮水、洗澡过程中呼吸吸入和皮肤接触4种暴露途径产生的总的平均个人年健康风险值为1.63×10-7～6.21×10-6 a-1,其健康风险排序为：翟家〉富官〉双树〉前庙〉土西〉大兀拉〉黄蜡坨〉前余〉大潘,均低于国际辐射防护委员会（ICRP）推荐的最大可接受值,基本属于可接受范围,但其健康危害已不容忽视。     

细河流域地下水中多环芳烃污染健康风险评价

为了保障细河流域沿岸居民的生活用水安全,采集细河流域9个地下水样品并分析了其中16种多环芳烃（PAHs）的含量,根据毒性当量因子方法和荷兰公共卫生和环境国家研究院提出的土壤地下水污染现场暴露评价模型（CSOIL模型）对多环芳烃的健康风险进行了初步评价。结果表明,细河流域各采样点地下水中∑PAHs含量为159.1～483.7 ng.L-1,低于生活饮用水卫生标准（GB 5749—2006）的浓度限值,表现出规模较大的城镇或乡镇处∑PAHs含量高于其他位置的规律性。作物食入、饮水等经口摄入途径是地下水环境健康风险评价中最主要的暴露途径,各采样点地下水中PAHs在作物食入、饮水、洗澡过程中呼吸吸入和皮肤接触等4种暴露途径产生的总的平均个人年健康风险值为1.19×10-6～3.10×10-5,其健康风险排序为翟家〉前庙〉富官〉前余〉双树〉土西〉大潘〉黄蜡坨〉大兀拉。虽然该风险值低于国际辐射防护委员会（ICRP）推荐的最大可接受值,基本属于可接受范围,但其健康危害已不容忽视。     

蔬菜大棚种植区土壤与地下水中典型有机污染物健康风险评价

在对石家庄某蔬菜大棚种植区进行采样测试分析的基础上,针对其表层土壤及地下水有机污染特征,依托美国环保局(U.S.EPA)所提健康风险评价四步法,以菜农为敏感人群,尝试开展蔬菜大棚种植区的健康风险评价工作。在评价过程中,主要考虑经口摄入土壤和饮用地下水两种暴露途径,而鉴于蔬菜大棚内表层土壤与大棚周围表层土壤中污染物种类和含量存在明显差异这一事实,又将经口摄入土壤途径细分为经口摄入大棚内表层土壤和经口摄入大棚外表层土壤。评价结果显示,菜农的非致癌风险和致癌风险目前均处于可接受风险水平;邻苯二甲酸二正丁酯是最主要的非致癌污染物,其非致癌风险贡献率高达84.2%,狄氏剂是最主要的致癌污染物,其致癌风险贡献率为51.35%;饮用地下水途径是最主要的非致癌风险贡献途径,其非致癌风险贡献率高达94.42%;经口摄入棚外表层土壤途径是最主要的致癌风险贡献途径,其致癌风险贡献率为47.14%。     

某有机化工污染场地土壤与地下水风险评估

以江苏某有机化工污染场地为例,采用美国RBCA(risk based corrective action)风险评估软件,并依据我国《污染场地风险评估技术导则》(征求意见稿)对模型中的参数进行了本土化设定,开展了典型有机化工类场地土壤与地下水的人体健康与水环境风险评估。结果表明：研究场地土壤污染相对较轻,局部区域存在风险或危害,最大值分别为5.44×10-5和54;地下水污染相对严重,有6个点位存在不同污染物的风险或危害商超标,其中,1,2-二氯乙烷的最大致癌风险高达0.174,氯苯的最大非致癌危害商高达20 586。与保护人体健康的修复目标值相比,保护水环境的值要更为保守。由此,仅基于健康风险的修复仍然可能存在水环境风险,应当予以重视。     

土壤苯污染引起的饮用地下水健康风险评价

由于污染场地所引起的生态环境、食品安全和人体健康问题,污染场地的环境风险评价受到广泛关注。以某水源地油和苯等有机污染调查为依据,利用多介质暴露评价模型(MMSOILS模型),以苯为评价的目标污染物,分析烯烃厂不同分区的土壤苯污染对A地区造成的饮用地下水健康风险。结果表明,研究区4个分区中,裂解装置区的苯污染物释放是A地区地下水污染的主要来源,产生的饮水健康风险值为9.82×10-5,占总风险值的98.8%;而其他三个分区的影响较小;不同分区苯污染对A地区产生的饮水健康总风险值为9.94×10-5,大于美国环境保护署人体健康风险建议值10-6,对人体健康已经产生影响;裂解装置区的土壤苯污染作为饮水健康风险的主要来源,当其浓度值降低至1.32mgkg-1时,才能使其造成的饮水健康风险降低为10-6。     

长春市城区土壤重金属健康风险评价

为评价长春市城区表层土壤重金属人体健康风险,采集了352件表层土壤样品,测定了Cu、Pb、Zn、Cr、As、Hg和Cd含量。统计分析、环境背景值法和地质累积指数法分析表明所监测的7种重金属元素均为健康风险因子。采用《污染场地风险评估技术导则》推荐健康风险模型对表层土壤进行了健康风险评价,结果表明:除Cd外,各元素经口摄入暴露是人体城市表层土壤重金属暴露的最主要途径,Cd主要通过吸入和经口摄入两种方式暴露;从各元素的总非致癌危害指数(HIn)来看,As的非致癌健康风险最高,其次依次为Cr、Pb、Cu、Hg、Cd和Zn;叠加后的总非致癌风险指数平均值为1.13,表明研究区表层土壤金属污染已对城市居民构成了潜在健康风险,As对总风险的贡献最大。叠加后的总致癌风险指数(CRT)平均值为6.25×10-5,处于安全值范围内,不会对当地居民的健康构成较大风险,但应加强防范,As污染是主要风险因子。     

土壤环境质量指导值与标准研究Ⅳ.保护人体健康的土壤苯并[a]芘的临界浓度

：基于人体健康风险评估制定土壤环境质量指导值或标准是当前国际上广泛采用的方法.本文全面调研了国际上保护人体健康的土壤苯并[a]芘（B[a]P）的各类临界浓度,初步确定了量化土壤中B[a]P暴露剂量的暴露场景和暴露参数,率先提出了制定我国土壤中保护人体健康的B[a]P临界浓度的方法体系,这种方法可用来制定持久性有机污染物的土壤临界浓度.考虑了口腔摄入、皮肤接触、呼吸摄入和取食污染蔬菜摄入四个主要暴露途径,探讨了B[a]P的致癌风险水平为10-5或10-6时,农业用地、居住用地和工业用地方式下土壤中B[a]P的临界浓度,同时制定了保护地下水的土壤B[a]P的临界浓度.     

中国农田土壤重金属污染的人体健康风险评估：研究进展与展望

农田土壤重金属污染对食品安全和人体健康构成巨大的威胁。重金属主要通过经口摄入土壤、吸入土壤颗粒、皮肤接触和食物链摄取等暴露途径进入人体,其中经口摄入重金属污染土壤和农产品是主要的暴露途径。人体健康风险评估在农田土壤质量分类和风险管控中起着重要作用。因此,梳理了中国农田土壤重金属污染的人体健康风险评估的发展状况,介绍了人体健康风险评估的基本流程和评估技术,论述了影响人体健康风险评价准确性的主要因素及优化措施。在农田土壤重金属健康风险评估中,应加强耦合污染源识别技术、重视食物消费暴露途径、精准识别不同敏感受体、本土化敏感受体的暴露参数、纳入重金属的生物可给性,同时提高农田土壤重金属健康风险评估的准确性。未来可从加强应对健康风险评估过程不确定性的技术方法、考虑各种饮食的暴露途径和建立本土化的重金属毒性标准数据等多方面深化农田土壤重金属健康风险评估,以期推动中国农田土壤重金属人体健康风险评估的理论和技术发展。     

基于保护水环境的场地地下水风险评估模拟应用研究

以江苏省某溶剂化工场地为例，利用英国污染地块水文地质风险评估模型研究了该场地地下水污染物对场地内及周边水环境的影响。比较了稳态和非稳态地下水溶质迁移模型(Ogata Banks、Domenico、Time variant Domenico)对污染物在自然衰减条件下从污染源向场地边界迁移过程模拟。结果表明：该场地的地下水中苯、乙苯、氯苯、1,2-二氯苯、1,4-二氯苯、氯仿超过了地下水质量Ⅲ类标准，但场地内污染物对场地边界地下水的潜在环境风险基本可以忽略。Ogata Banks与Domenico模型对于污染物在含水层的自然衰减下的迁移模拟表明污染物在30 m内的迁移过程中浓度下降较快，在30 m外的迁移过程中污染物的浓度较低且衰减不明显。Domenico模型计算较为简洁，在风险评估中具有较强的适用性；敏感性分析表明合规点至污染源距离x、含水层容重ρ、含水层孔隙度n、有机碳含量f_oc、有机碳分配系数K_oc、水力传导系数K、水力梯度i均影响污染物在含水层的自然衰减迁移过程，通过精细化水文地质调查获取上述参数将有助于提高风险评估结果的精确度。     

宁波土壤中多环芳烃的健康风险评价

以宁波地区土壤中多环芳烃的含量调查结果为基础,采用美国能源部风险评估信息系统的暴露量化方法和美国环保局健康风险评估手册的风险表征方法,评估了土壤中16种多环芳烃对户外劳作者的健康风险。结果表明,宁波户外劳作者由于土壤中多环芳烃引起的平均非致癌危害指数为1.09×10-5,平均致癌风险值为3.17×10-7,可判定对人体健康的危害较小。宁波地区致癌多环芳烃含量最高暴露点致癌风险值为1.45×10-6,没有超过致癌风险水平上限（10-4）,说明致癌风险尚在可接受范围内。多环芳烃中苯并（a）芘对综合致癌风险贡献最大,贡献率高达65.6%,应注意防范土壤中该污染物引起的健康危害。宁波户外劳作者受到的非致癌危害和致癌风险主要由直接摄入途径和皮肤接触途径贡献,两种途径对非致癌危害和致癌风险贡献率分别达到89%和100%,呼吸摄入引起的非致癌危害和致癌风险则相对较小。     

Human health risk due to consumption of vegetables contaminated with carcinogenic polycyclic aromatic hydrocarbons

Purpose  

Polycyclic aromatic hydrocarbons (PAH) are persistent, toxic, and carcinogenic contaminants present in soil ecosystem globally. These pollutants are gradually accumulating in wastewater-irrigated soils and lead to the contamination of vegetables. Food chain contamination with PAH is considered as one of the major pathways for human exposure. This study was aimed to investigate the concentrations of PAH in soils and vegetables collected from wastewater-irrigated fields from metropolitan areas of Beijing, China. Origin of PAH, daily intake, and health risks of PAH through consumption of contaminated vegetables were studied.     

Risks due to groundwater contamination at a plutonium processing facility

The specter of contaminated groundwater looms over industrialized, suburban, and rural areas. The sources of groundwater contamination are many and the contaminants numerous. Historical waste disposal practices pose the greatest threat to groundwater in the United States. Common solvents such as trichloroethylene, tetrachloroethane, benzene, and carbon tetrachloride have been found in widespread areas. For this study, a risk assessment is performed using a multimedia environmental transport model to estimate public risk from a contaminated groundwater plume. From 1955 to 1973, a crib above the groundwater plume was used for the disposal of plutonium processing waste. The plume contains chemical and radioactive wastes that could pose a health threat to people living in the vicinity of the site. Remedial designs are selected for remediating the different contaminants in the groundwater plume through a multiple phase treatment process. This study evaluates: baseline health risks to the public, health risk reduction to the public as a result of the remedial activities, health risk to the workers directly involved in cleaning up the site, and costs associated with each remedial activity.     

Human health risk assessment and risk source analysis of arsenic in soil from a coal chemical plant in Northwest China

Purpose

Arsenic (As) is a potentially toxic element and poses risks to human health during coal chemical technology application. Human health risk of As in coal chemical industry was seldom reported. The results of As human health risk distribution for the entire coal chemical plant in our study may provide theoretical and practical support to reduce human health risk of As in coal chemical industry.

Materials and methods

We collected 153 soil samples with a chessboard sampling method in a coal chemical plant in northwestern China. Arsenic concentrations in the soil were measured with inductively coupled plasma mass spectrometry (ICP-MS) after the soil samples were digested. Human health risk of As was assessed through three exposure pathways including inhalation, skin contact, and oral intake. A human health risk distribution map of As for the entire plant was obtained by kriging method.

Results and discussion

The integrated carcinogenic risk of As in the soil was 8.59–13.31 times of the acceptable standard (1.00E-06), which was established by the Ministry of Environmental Protection of China, while the hazard quotient was within the acceptable range (<?1.00). Oral intake, through which 76.61% of the total carcinogenic risk was contributed, was the main pathway of As to human body and gave the smallest control threshold (1.59 mg kg^?1) among the three exposure pathways. The smallest control threshold was recommended as the safety control threshold of As in this plant. Moreover, the highest carcinogenic risk and the largest hazard quotient were found in the Power Unit and its downwind direction (in the southeast of plant) because of As disposal and the local prevailing wind.

Conclusions

In the present study, As spatial distribution in the soil was obtained. A map of As human health risk distribution for the entire coal chemical plant was obtained with kriging method based on limited sampling points, which was more robust compared with traditional methods. Arsenic human health risk sources were also analyzed. The results may be applied in the process of reducing human health risk of As in coal chemical industry.

     

苏南某焦化厂场地土壤和地下水特征污染物分布规律研究

以苏南某焦化厂为研究对象,在对污染区域初步识别的基础上,采集了0～4.5 m深的22个土壤样品和2个地下水样品,利用GC/MS等检测了多环芳烃类、总石油烃、苯系物、重金属,总氰化物、挥发酚、硫化物的含量,并研究了其在不同功能区土壤和地下水中的特征分布。结果表明：（1）该焦化场土壤和地下水受到了不同程度的污染,其中炼焦炉周边、焦油和洗油储罐区、焦油和粗苯加工车间是污染最严重的区域;（2）土壤中主要超标污染物是多环芳烃、总氰化物、总石油烃、单环芳香烃、二苯呋喃、苯胺、硫化物、挥发酚和一些苯酚类化合物;（3）地下水重点污染区域粗苯车间受到总氰化物、苯胺、苯酚类、萘、总石油烃、单环芳香烃的严重污染,污水处理站区域地下水主要污染物包括总氰化物、萘、总石油烃、苯。     

一种基于模糊的修复后土壤环境风险综合评价方法

Environmental risks pertaining to contaminated soils have been well studied, while little attention has been paid to the risks of the soils after remediation. In this study, a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators, namely, plant growth, groundwater safety and human health, of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover, great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general, the risks of both polluted and restored soils to the environment were in the order of groundwater safety 〉 plant growth 〉 human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers, which made it helpful in decision-making and management of restored soils.     

Heavy metal and chlorinated hydrocarbon contamination of selected aquatic sediments from the Berlin area

Sediments from the Berlin area were analysed for heavy metals and chlorinated hydrocarbons. the sedimentological and hydrogeological aspects of the Holocene sediments are discussed and an adapted sampling device for muds with a high water content is described. the contamination of surface sediments and dated cores is shown back in the 19th century; the hydrological influences on the degree of contamination and potential threats to groundwater and, via remobilisation, to surface waters are considered. It is concluded that the sediments of the Berlin area are highly contaminated.     

Remediation Actions by a Risk Assessment Approach: A Case Study of Mercury Contamination

The risk assessment procedure for identifying the remediation actions which may be adopted at a mercury contaminated site, when the plants are upgraded in the future, is proposed. The potentially active exposure/migration pathways in the future arrangement of the area will be due to Hg contaminated subsoil as a primary source (vapor inhalation and groundwater leaching) and to groundwater as a possible secondary source (transport to the point of compliance). The data of mercury concentration in the soil were acquired through environmental monitoring campaigns, and were processed to establish the three-dimensional distribution of contamination in subsoil, to locate sources and to define their geometrical and chemical characteristics. Speciation tests of mercury in the soil indicated that the most abundant species present were poorly leachable under the site-specific environmental conditions, confirming the coefficient distribution value obtained by the leaching tests. Analytical and numerical fate and transport modeling tools were used to locate digging zones in the contaminated subsoil, so as to reduce the possible groundwater contaminant loading and to avoid the down-gradient exceeding the concentration limit according to regulations. Remediation actions additional to civil works were required, which consists of soil digging within one contamination source, for about 22,200 m³ of soil. In order to evaluate the Hazard Index (HI) for human receptors due to Hg vapor inhalation, the air concentration of volatile mercury at the exposure point was estimated, based on direct measurements carried out at the site. Simulation gave HI values below 1 for all tested scenarios, suggesting that public health is protected without any additional actions to the already scheduled plant upgrading and digging for groundwater protection.     

典型地区多介质环境中多氯联苯、镉致癌风险评估

对典型地区多种环境介质土壤(n=151)、地下水(n=9)、大气(可吸入颗粒物(PM10)和气态污染物,n=4)及农作物(蔬菜(n=38)和大米(n=95))进行采样,分析其中多氯联苯(PCBs)和镉(Cd)含量,利用美国EPA致癌风险评估模型评估研究区居民经多种途径接触多种介质引起的PCBs和Cd的致癌暴露剂量和致癌风险.进行致癌风险贡献率分析,筛选出主要的致癌污染物、暴露途径及对致癌风险贡献最大的环境介质.研究结果表明,所调查的环境介质中均存在严重的PCBs、Cd污染,蔬菜和大米中Cd的平均含量分别为我国食品中污染物限量标准的130倍和17倍,地下水中PCBs和Cd超标率均很高,大气中气态PCBs及PM10颗粒态PCBs、Cd含量均高于国内外其他地区的调查结果.致癌暴露剂量评估结果表明PCBs、Cd的总致癌暴露剂量分别为允许摄入量的6.8倍和6.1倍,总致癌风险为1.1×10-3,远高于国内外所规定的可接受致癌风险水平;致癌贡献率分析结果表明经口摄入是研究区居民致癌风险的最主要暴露途径,蔬菜、大米和地下水是该地区最主要的PCBs、Cd致癌风险来源.