典型石化企业排放有毒有害大气污染物人体健康风险评估

石化行业生产过程中会产生有毒有害大气污染物,并可能对人体健康产生危害。为贯彻落实《大气污染防治法》第七十八条中对有毒有害大气污染物(hazardous air pollutants,HAPs)实行风险管理,评估环境风险的要求,有必要开展石化企业排放HAPs的人体健康风险评估。本研究采用美国环境保护局(US EPA)发布的人体健康风险评估手册F部分吸入风险评估指南中的方法,推算出HAPs物质对人体健康的致癌风险值和非致癌风险值;通过CALPUFF模型模拟预测出典型石化企业HAPs物质扩散范围及空气中的浓度,并将模拟预测得到的污染物浓度与推算得到的风险值进行比较,进而表征园区内该企业排放HAPs对人体健康的风险。结果表明,基于最坏情况分析,该石化企业排放的HAPs致癌风险值为0.421μg·m-3,非致癌风险值为2.212μg·m-3,CALPUFF模拟预测空气中污染物浓度最大为0.62μg·m-3,且模型预测的月均浓度均未超过致癌和非致癌风险值,风险表征结果表明,该石化企业排放的HAPs物质对人体健康不存在致癌和非致癌风险。但本研究仅针对某石化企业开展人体健康风险评估,并不能代表石化行业排放有毒有害大气污染物对人体健康风险的整体水平。     

C-RAG模型在砷污染场地中的修正及应用研究

为了解我国基于人体健康《建设用地土壤污染风险评估技术导则》 (Chinese Risk Assessment Guide, C-RAG)在矿区场地中的分析模式及应用情景,以青海某废弃矿区场地为例,在结合矿场未来规划的基础上,通过对C-RAG模型参数的修正和改进,研究了该场地的风险状况及修复目标值,为污染地块适度修复提供了借鉴依据.结果表明,以砷污染为主的矿区场地,在修正暴露途径、土壤摄入量、暴露频率和PM10 后,致癌风险水平普遍降低为原来的1/4.综合考虑污染物的可给性、风险水平与修复投入之间的平衡关系以及工程可行性后,确定以引入生物可给性的致癌风险控制值21.1 mg·kg-1为最终修复目标值.     

2种毒性评估方法对PAHs污染场地人体健康风险的比较研究

毒性评估是人体健康风险评价的重要部分,目前主要存在2种方法,一种基于PAHs相对于苯并[a]芘(BaP)的毒性当量因子,采用Ba P致癌斜率因子参数(方法 1),另一种直接采用各PAHs致癌斜率因子和非致癌参考剂量等参数(方法 2)。然而2种毒性评估方法得到的风险及修复量是否存在差异以及引起差异的原因等问题鲜有讨论。针对苏南某焦化厂PAHs污染土壤,采用分层土壤健康风险评价模型,对比了2种毒性评估方法确定的PAHs风险、修复目标污染物及土方量的差异,并对引起差异的关键因素进行探讨。结果表明:对于0.0~1.0 m表层土壤,方法 1和方法 2确定的致癌风险最大值分别1.48E-05和1.32E-05,均超过可接受致癌风险,修复土方量分别为27 846 m~3和28 667 m3,修复目标污染物均为Ba P和二苊烃(Acy)。对于1.0~3.0 m深层土壤,方法 1确定的致癌风险最大值为3.36E-08,低于可接受致癌风险,不需要修复;而方法 2确定的致癌风险最大值为3.73E-04,非致癌危害指数最大值为6.96E+01,分别超过可接受致癌风险和非致癌危害商,需要修复,修复目标污染物为萘(NaP),修复土方量为35 944 m~3。最终,方法 2确定的总修复土方量(64 611 m~3)为方法 1确定土方量(27 846 m~3)的2.45倍,而这种差异主要是由于方法 1低估了深层土壤中高挥发性PAH单体尤其是NaP的风险所致。因此,从保守角度建议采用方法 2进行PAHs风险评价。     

贵阳市西郊水厂所供管网末梢水重金属污染物季节性特征及潜在健康风险评价

以贵阳市西郊水厂2014年3月和7月所供管网末梢水中10种重金属污染物检测数据为基础,进行了季节性特征分析,并采用美国环保局(USEPA)推荐的健康风险评价模型进行了潜在健康风险评价。结果表明,贵阳市西郊水厂所供管网末梢水中10种重金属的浓度均符合国家饮用水卫生标准;重金属污染物的浓度随季节呈现出不同的特征,汞、锌、硒、钼和钡5种重金属的平均浓度呈现枯水期高于丰水期的特征,而铅、铜、锰和镍4种重金属正好相反,砷浓度的季节性特征不显著;成年人的年平均致癌风险显著大于儿童,但两者年平均非致癌风险接近;儿童和成年人2类人群经口暴露途径的健康风险值均大于皮肤暴露,其中致癌风险分别在2.49×10-6~9.16×10-6和3.26×10-8~9.59×10-8之间,非致癌风险在2.29×10-8~3.20×10-8和1.85×10-10~4.14×10-10之间,且致癌风险均大于非致癌风险。贵阳市西郊水厂所供管网末梢水中10种重金属污染物致癌风险和非致癌风险均未超过最大可接受水平,未对该供水区居民的健康造成威胁。     

场地土壤重金属污染健康风险评价及固化处置——以东莞市某电镀厂搬迁场地为例

以广东省东莞市某典型电镀厂搬迁场地为研究对象,在对搬迁场地土壤进行全面调查及土壤重金属污染风险评价的基础上,研发了基于粘土矿物的重金属深度固化技术,以重金属污染土壤为原料制备烧结砖体,实现重金属污染土壤的资源化利用。土壤重金属含量分析结果表明46个土壤样品中镉、汞、镍及锌含量均低于中国《土壤环境质量标准》(GB 15618─1995)中二级标准值,但砷、铜、铬和铅含量在部分样点高于国家二级标准值。健康风险评价结果显示该场地中铬、铅、砷和铜对儿童存在潜在的非致癌危害,而砷对成人、儿童均存在明显的致癌风险。在以上该场地土壤重金属含量调查和重金属健康风险评价基础上,对重金属超标土壤采用基于矿物晶体结构的异位固化处置,以粘土为基质,使污染土壤与粘土充分混合后压制成砖,煅烧后重金属以晶体结构的形式固定于砖体中。采用美国环保署EPA基于毒性对废物进行危险或非危险性鉴别的标准方法 TCLP(US EPA 1311)的毒性浸出实验结果表明,浸出液中重金属浓度低于《地表水环境质量标准》(GB 3838─2002)三类水标准值,实现场地重金属污染土壤的无害化处置。该研究针对典型搬迁工业场地建立了一套行之有效的重金属污染土壤风险评价及无害化处置的工艺流程,可为促进广东省土壤污染修复产业的形成与发展提供借鉴。     

废弃铅锌冶炼厂重金属污染场地的健康风险评价

通过对广西某废弃铅锌冶炼厂区进行布点采样、监测分析,选取Cu、Pb、Zn、Cd、Cr、As六种重金属元素作为评价因子,对污染场地进行健康风险评价.结果显示,指数评价法表明厂区污染状况为废渣＞＞建筑垃圾＞土壤,Cd ＞Zn ＞As ＞Pb ＞Cu＞ Cr,土壤受到中度污染,废渣和建筑垃圾受到重度污染.健康风险评价法表明土壤、废渣和建筑垃圾的危害商分别为2.032、13.891、2.975,非致癌危害废渣＞＞建筑垃圾＞土壤;Cu、Zn、Cr、Cd、As的危害商分别为0.053、0.118、0.184、7.001、11.542,非致癌危害As ＞Cd ＞Cr＞Zn ＞Cu.土壤、废渣和建筑垃圾的致癌风险分别为5.387E-04、7.954E-04、2.455E-04,致癌危害废渣＞土壤＞建筑垃圾;As、Cd、Cr的致癌风险分别为5233E-04、2.400E-05、1.032E-03,致癌危害Cr＞As ＞Cd.综上,人体健康危害废渣＞建筑垃圾＞土壤,主要危害元素为As、Cd、Cr.     

某冶炼厂拆迁场地土壤重金属污染健康风险评价

按照环保部最新颁布实施的污染场地风险评估技术导则(HJ 25.3—2014),选取Cu、Pb、Zn、Cd、Cr、As 6种重金属元素为主要污染物,结合Pearson相关分析及克里金差值法,对某冶炼厂拆迁场地土壤进行健康风险评价。结果表明:拆迁场地土壤中重金属污染集中于生产区及堆放场,污染程度为生产区≈堆放场生活区,6种重金属平均值低于《展览会用地土壤环境质量评价标准》B级(HJ 350—2007),Pb、Zn、Cd平均值高于广西省和中国土壤元素背景值;相关分析表明Cu分别与Pb、Zn、Cr、As,Pb-Cr、Pb-As及Zn-Cd存在极显著正相关关系;健康风险评价结果表明生活区土壤中6种重金属对人体健康不会产生不良或危害效应;生产区和堆放场土壤中Cr存在致癌风险,As存在致癌风险和非致癌危害。成人血铅模型(ALM)计算得出生活区、生产区及堆放场中成人血铅浓度值分别为4.98μg·d L-1、5.04μg·d L-1、5.03μg·d L-1,低于成人血铅浓度风险评价的基准值5.8μg·d L-1,且Pb的平均值低于国内外居住用地土壤铅环境基准值。     

利用靶器官毒性剂量法(TTD)和证据权重分析法(WOE) 评估固化飞灰中重金属非致癌健康风险

传统的健康风险评价方法未考虑重金属对多种靶器官的影响及重金属间的相互作用,不能反映重金属真实的风险情况.ATSDR的靶器官毒性剂量法(TTD)和EPA的证据权重分析法(WOE)分别将重金属能够产生效应的靶器官与重金属间的相互作用引入评价过程,对传统评价方法进行修正.基于此,本研究采用了TTD法和WOE法评估了生活垃圾焚烧厂固化飞灰中重金属的非致癌健康风险,并将其与传统的非致癌健康风险评价方法进行比较.结果表明,传统的非致癌健康风险评价方法得出的HI值为0.2084,经TTD法和WOE法修正后的HI值分别为0.5165和0.6717,修正后风险大于传统方法所预测风险,更严格的反映固化飞灰对工人健康的真实风险.     

新疆焉耆盆地农田土壤重金属污染及健康风险评价

为研究新疆焉耆盆地绿洲农田土壤重金属的污染及潜在健康风险,选取194个样点采集土壤样品,测定As、Cd、Cr、Cu、Ni、Pb和Zn共7种重金属元素含量。利用地质累积指数(I_(geo))评价农田土壤污染水平,采用US EPA健康风险评价模型,对农田土壤重金属污染的潜在健康风险进行评估。结果表明,研究区农田土壤7种重金属平均含量均未超出《食用农产品产地环境质量评价标准》中的限值,但Cd、Cr、Ni、Pb和Zn含量平均值分别超出新疆灌耕土背景值的1.67、1.41、1.30、3.01和6.78倍。农田土壤中Zn呈现轻度污染,Cd与Pb呈现轻微污染,As、Cr、Cu与Ni呈现无污染态势。健康风险评估结果表明,经手-口摄入是研究区农田土壤重金属日均暴露量及健康风险主要途径。农田土壤7种重金属通过3种暴露途径的非致癌风险商(HQ)与非致癌风险指数(HI),单项致癌风险指数(CR)与总致癌风险指数(TCR)均小于安全阈值,属于可接受风险水平。研究区农田土壤重金属对儿童的非致癌风险低于成人,致癌风险高于成人。研究区农田土壤中As与Pb是最主要的非致癌风险因子,As是最主要的致癌风险因子,研究区农田土壤中As对人体的健康风险应当引起重视。     

西南某矿区家庭灰尘中重金属的暴露及其健康风险评价

家庭灰尘是人群居住场所的重要环境介质,人群可通过吸入、摄食及皮肤接触等途径摄入灰尘中的污染物,对健康造成一定的损伤。为探索我国西南某矿区周边村庄室内重金属的污染对人群健康的潜在风险,采用2014年3月对我国西南某矿区周边村庄室内灰尘中重金属污染水平调查的数据,结合美国EPA健康风险评价模型对人群健康风险进行分析。结果表明:人群非致癌风险和致癌风险暴露剂量均表现为儿童>成人男性>成人女性,呈现手-口摄食途径>皮肤接触途径>吸入途径,其中儿童、成人男性和成人女性手-口摄食暴露途径占总暴露剂量的98.16%、55.61%和51.5%;儿童以Pb、Cr的暴露为主,成人以Cr的暴露为主;家庭灰尘中单种重金属元素和多途径叠加的非致癌风险在8.81E-03~1.24E-02之间,均小于1,其中儿童以Pb的非致癌风险为主,经手-口摄食暴露占总风险的40%;致癌风险在4.19E-05~3.35E-04之间;A、B、C村儿童的致癌风险均高于US EPA所推荐的可接受水平10-4,其暴露剂量和健康风险均为成人男性和成人女性的5~6倍,且以Cr通过手-口摄食暴露产生的风险最大,占总风险的93%左右。     

Probabilistic framework for assessing the arsenic exposure risk from cooked fish consumption

Geogenic arsenic (As) contamination of groundwater is a major ecological and human health problem in southwestern and northeastern coastal areas of Taiwan. Here, we present a probabilistic framework for assessing the human health risks from consuming raw and cooked fish that were cultured in groundwater As-contaminated ponds in Taiwan by linking a physiologically based pharmacokinetics model and a Weibull dose–response model. Results indicate that As levels in baked, fried, and grilled fish were higher than those of raw fish. Frying resulted in the greatest increase in As concentration, followed by grilling, with baking affecting the As concentration the least. Simulation results show that, following consumption of baked As-contaminated fish, the health risk to humans is <10^?6 excess bladder cancer risk level for lifetime exposure; as the incidence ratios of liver and lung cancers are generally acceptable at risk ranging from 10^?6 to 10^?4, the consumption of baked As-contaminated fish is unlikely to pose a significant risk to human health. However, contaminated fish cooked by frying resulted in significant health risks, showing the highest cumulative incidence ratios of liver cancer. We also show that males have higher cumulative incidence ratio of liver cancer than females. We found that although cooking resulted in an increase for As levels in As-contaminated fish, the risk to human health of consuming baked fish is nevertheless acceptable. We suggest the adoption of baking as a cooking method and warn against frying As-contaminated fish. We conclude that the concentration of contaminants after cooking should be taken into consideration when assessing the risk to human health.     

Distribution,sources and potential risk of HCH and DDT in soils from a typical alluvial plain of the Yangtze River Delta region,China

Spatial distribution, sources and potential health risks of organochlorine pesticides (OCPs), including hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in surface soils (n = 544) collected from a typical alluvial plain of the Yangtze River Delta region, China, were elucidated. Concentrations of ΣHCH and ΣDDT in soils ranged from less than the limit of detection (<LOD) to 99.0 ng g^?1, dry weight (dw) (mean 3.23 ng g^?1 dw) and <LOD to 600 ng g^?1 dw (mean 88.8 ng g^?1 dw), respectively. Historical applications of HCH and DDT were the major sources of the residue in soils. HCH was mainly distributed in Anthrosols in the southern part of the watershed, while DDT was mainly distributed in Cambosols in the northern part. The 95 % cumulative probability incremental lifetime cancer risks (ILCRs) of different age groups such as children, youths, and adults all exceeded the acceptable risk level of 10^?6 recommended by USEPA for carcinogenic chemicals. The spatial distributions of ∑ILCRs were consistent with concentrations of OCPs in soils, while they were slight different for the different age groups. Adult females had the greatest risk of OCPs in soils, followed by children, while youths had the least risk. The ingestion of OCPs in soils was the more important route of exposure compared with dermal and inhalation exposures. The concentration of OCPs in soils, the particulate emission factor, the fraction of dermal exposure ratio, and the soil ingestion rate were the major contributing variables to total ILCRs according to sensitivity analyses.     

前哨动物在环境污染物人体健康风险评价中的应用

前哨动物能够在污染物对生态系统或人体健康产生明显影响之前做出反应,所以利用前哨动物能够对环境污染的健康风险做早期预报,同时可提供环境中污染物种类、污染水平、生物可利用性、富集代谢等多方面的信息.虽然来自前哨动物的信息不能直接外推于人,但由于动物和人体结构和功能的相似性,这些信息可作为污染物对人体作用的早期警报.论文对作为前哨动物的某些鱼类、两栖动物和哺乳动物在环境污染物人体健康风险评价中的应用进行了简要概述,讨论了它们作为前哨动物各自的优缺点和适用范围,最后建议在国内大力开展前哨动物生态毒理学调查,以促进人体健康风险评价工作.     

北京市典型有机设施蔬菜基地重金属污染特征及风险评估

为研究北京市典型有机设施蔬菜基地重金属污染状况,采用野外调查及室内分析法,选取北京市5个有机设施蔬菜基地中125个土壤样品和77个蔬菜样品进行了Pb、Cd、Cr、As和Hg含量的检测、统计分析与评价,对土壤重金属含量与土壤理化指标进行了相关分析,研究了重金属在蔬菜中的迁移规律,并结合美国环保署(US EPA)推荐采用的健康风险评价模型,评价由于蔬菜摄入导致的成人和儿童的健康风险。结果表明,5个设施蔬菜基地中有极少数土壤样本Cd含量超标,有极少数叶菜样本Cr含量超标,其他重金属含量均未超标。污染指数评价表明5个基地土壤重金属污染排序为:基地5基地1基地3基地2基地4,主要由土壤Cd累积所致。土壤重金属与理化性质相关性表明,5种重金属含量都受土壤的理化性质影响较大。总体上,5种重金属在土壤-蔬菜中迁移能力排序为:CdHgAsCrPb,在不同类蔬菜中的富集系数排序为:叶菜类茄果类瓜果类豆菜类。5种重金属造成的目标危害系数大小依次为:CdPbAsHgCr,不同类蔬菜的综合重金属目标危害系数值排序为:叶菜类茄果类瓜果类豆菜类,所有蔬菜单一重金属目标危害系数和复合危害系数都远小于1,说明单一重金属和复合重金属污染对成人和儿童都没有明显的负面健康影响。     

宝鸡市街道灰尘重金属污染的健康风险评价

对宝鸡市工业区、交通区和商业区等不同功能区所采集的街尘样品应用美国EPA人体暴露风险评价方法对灰尘重金属进行健康风险评价.结果表明,As、Hg、Pb、Cu、Zn、Cr、Co、Ni、Mn、V这10种重金属平均含量均高于陕西土壤背景值,其中Hg、Pb平均含量分别为陕西土壤背景值的37倍和20倍.健康风险评价表明,灰尘中10...     

Human health risk assessment of explosives and heavy metals at a military gunnery range

In this research, a risk assessment was undertaken in order to develop the remediation and management strategy of a contaminated gunnery site, where a nearby flood controlling reservoir is under construction. Six chemicals, including explosives and heavy metals, posing potential risk to environmental and human health, were targeted in this study. A site-specific conceptual site model was constructed, based on effective, reasonable exposure pathways, to avoid any overestimation of the risk. Also, conservative default values were adapted to prevent underestimation of the risk when site-specific values were not available. The risks posed by the six contaminants were calculated using the API’s Decision Support System for Exposure and Risk Assessment, with several assumptions. In the crater-formed-area (Ac), the non-carcinogenic risks (i.e., HI values) of tri-nitro-toluene (TNT) and Cd were slightly larger than 1, but for RDX (Royal Demolition Explosives) was over 50. The total non-carcinogenic risk of the whole gunnery range was calculated to be 62.5, which was a significantly high value. The carcinogenicity of Cd was estimated to be about 10⁻³, while that for Pb was about 5 × 10⁻⁴, which greatly exceeded the generally acceptable carcinogenic risk level of 10⁻⁴–10⁻⁶. It was concluded from the risk assessment that there is an immediate need for remediation of both carcinogens and non-carcinogens before construction of the reservoir. However, for a more accurate risk assessment, further specific estimations of the changes in environmental conditions due to the construction of the reservoir will be required; and more over, the effects of the pollutants to the ecosystem will also need to be evaluated.     

Investigating into composition,distribution, sources and health risk of phthalic acid esters in street dust of Xi’an City,Northwest China

Phthalic acid esters (PAEs) are widely used as plasticizers and in consumer products, which may enter the environment and present risks to human health. U.S. EPA classifies six PAEs as priority pollutants, which could be accumulated in street dust at the interface of atmosphere, biosphere and geosphere. This study collected a total of 58 street dust samples from Xi’an City in Northwest China and analyzed for concentrations of the priority PAEs. Composition, distribution, sources and health risk of the PAEs were further examined. All the priority PAEs were detected in the street dust. The concentrations of individual PAEs varied between not detected and 183.19 mg/kg. The sum of the 6 priority PAEs (∑6PAEs) ranged from 0.87 to 250.30 mg/kg with a mean of 40.48 mg/kg. The most abundant PAEs in the street dust were di-n-butyl phthalate and di (2-ethylhexyl) phthalate (DEHP). Higher concentrations of ∑6PAEs in the street dust were found in the south and west parts of Xi’an City as well as its urban center, which were possibly attributed to the prevailing northerly Asian winter monsoon. The PAEs in the street dust originated mainly from wide application of plasticizers as well as cosmetics and personal care products. The main pathways of human exposure to PAEs in the street dust were ingestion and dermal adsorption of dust particles. The non-cancer risk of human exposure to PAEs in the street dust was relatively low, while the risk to children was higher than that to adults. The cancer risk of human exposure to DEHP in the street dust was lower than the standard limit value of 10^?6.     

Distribution and sources of phthalate esters in the topsoils of Beijing,China

Phthalate esters in the topsoil samples collected from Beijing were determined by derivatization and gas chromatography–mass spectrometry techniques. The results showed that diethyl phthalate (DEP), diisobutyl phthalate ester (DIBP), dibutyl phthalate ester (DBP), dibutyl (2-ethyl hexyl) phthalate (DEHP), and dimethyl phthalate (DMP) were found in the topsoils. The total concentrations of the five phthalate esters varied from 2.30 to 24.71 μg g^?1. According to phthalate esters (PAEs) control standards in soil of the USA, the standard exceeding rates of DMP, DBP, and DEHP were 100 %, 100 %, and 4.84 % in soils of Beijing, respectively. The rate of DBP exceeding soil remediation standard was 12.9 %. Overall, concentrations of PAEs in Beijing were at a high level in China. The concentrations of DBP, DEHP, and DIBP were high, and the total concentrations of all the phthalate esters were higher in the areas with intensive human activities than in the other areas, which may be related to the use of phthalate compounds (such as the use of plastic products). The total and individual concentrations of phthalate compounds were relatively low in the areas that used plastic films compared with other samples due to the diffusion of atmospheric motion, categories, and amounts of plastic products and other factors. The greatest contributor may be the usage amount of plastic products in people’s daily lives.