典型野生食用菌重金属含量及其人体健康风险评价

土壤重金属污染是影响生态环境、食品安全和人体健康的重要因素.云南省土壤重金属背景值较高,且矿产资源丰富、采矿活动频繁,导致土壤重金属含量较高.野生食用菌是高效重金属储积器,云南是中国野生食用菌最大产区.因此,本文以云南省8种典型野生食用菌为研究对象,探究其重金属含量(汞、镉、铅、锌、铜、砷)与分配特征,采用单因子污染指数对其进行重金属污染评价,利用概率方法(THQ指数)评估其对不同年龄人群(成人、儿童)的人体健康风险.研究结果表明,不同种类野生食用菌重金属含量存在显著差异(P<0.05).Hg、Cd、Pb、Zn、Cu浓度范围分别为0.5—7.2、0.3—15、0—26.8、47.7—214、56.7—428 mg·kg^-1 dw;As未检出.此外,Hg、Cd、Pb、Zn、Cu均主要分布于菌盖.除虫草花、白森、干巴菌中Hg未检出,其余重金属污染评价中单因子污染指数均>1,且同一元素在同种野生食用菌不同部位污染程度不同,其中,老人头菌盖受Cd污染最为严重.基于国家食品安全标准,本研究中98%野生食用菌Hg、Cd、Pb含量超标.然而,THQ指数表明,部分野生食用菌中Zn无风险(THQ<1),老人头菌盖、鸡枞菌盖中Cd、Hg、Pb、Cu具有人体健康风险(THQ>1),且风险值儿童>成人.     

Health hazard prospecting by modeling wind transfer of metal-bearing dust from mining waste dumps: application to Jebel Ressas Pb–Zn–Cd abandoned mining site (Tunisia)

This work presents a modeling approach to simulate spatial distribution of metal contamination in aerosols with evaluation of health hazard. This approach offers the advantage to be non-intrusive, less expensive than sampling and laboratory analyses. It was applied to assess the impact of metal-bearing dust from mining wastes on air quality for a nearby community and agricultural lands in Jebel Ressas (Tunisia) locality. Dust emission rates were calculated using existing parameterization adapted to the contamination source composed of mining wastes. Metal concentrations were predicted using a Gaussian model (fugitive dust model) with, as input: emission rates, dump physical parameters and meteorological data measured in situ for 30 days in summertime. Metal concentration maps were built from calculated PM10 particle concentrations. They evidence the areas where Pb and Cd concentrations exceeded WHO guidelines (0.5 and 0.005 µg/m³, respectively). Maximum concentrations of Pb and Cd in PM10 are, respectively, of 5.74 and 0.0768 µg/m³ for measured wind speed values up to 22 m/s. Preferential areas of contamination were determined in agricultural lands to the NW from the source dump where Pb and Cd exceeded guidelines up to a distance of 1,200 m. The secondary spreading directions were SW and E, toward the village. Health hazard prospecting shown that a major part of the village was exposed to contaminated dust and that daily hazard quotient (HQ) values reached locally 118 and 158, respectively, for Pb and Cd during the study period. However, HQ variations in the village are high, both temporally and geographically.     

工业城市不同功能区土壤和蔬菜中重金属污染及其健康风险评价

为了研究和评价工业城市不同功能区的土壤和蔬菜中重金属污染和健康风险状况,以株洲市为例,在工业区（石峰区）、农业区（芦淞区）和旅游区（大京风景区）分别采集土壤和蔬菜样品,分析重金属Cd、As、Pb、Hg、Zn、Cr和Cu的质量分数,并采用地质累积指数法（Igeo）和健康风险评价模型分别对土壤和蔬菜中重金属进行评价。结果表明：工业区、农业区和旅游区土壤中Cd、As、Pb、Hg、Zn、Cr和Cu的平均质量分数都超出湖南省土壤背景值,部分重金属甚至超出国家土壤环境质量二级标准。不同功能区土壤中重金属的地质累积指数（Igeo）表明：工业区、农业区和旅游区土壤受到不同程度的重金属污染,其中Cd和Hg的污染最为严重,污染程度依次是工业区〉农业区〉旅游区。不同功能区蔬菜中Cd、As、Pb和Zn的危害商（HQ）值都大于1.0,而Cu和Cr的危害商（HQ）都小于1.0。不同功能区蔬菜中重金属危害指数（HI）都大于10.0,尤其是工业区蔬菜的危害指数（HI）〉100.0,当地成年人食用受到重金属污染的蔬菜会导致严重的健康危害,其中Cd和As,是危害指数（HI）的主要贡献者,两者贡献率之和的范围为75%~89%,而Cr的贡献率几乎为0。     

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。     

Assessment of metals in fourteen species of vegetables and crops cultivated in a suburban area using multivariate analyses

Concentrations of seven metals (Cd, Cr, Mn, Ni, Pb, V, and Zn) were determined in 14 plant species including vegetables and crops from an agricultural area located at the Southern part of the Iranian capital, near the Tehran oil refinery. Different statistical methods, especially multivariate ones, were employed for the analysis of the results. Based on the results of agglomerative hierarchical method for clustering of the grid cells, some similarities between the dendrograms of Pb, Ni, and V and, furthermore, between Mn and Cr were observed that could be attributed to their similar distribution sources in the study area. The principal component analysis showed that with respect to accumulation of all the metals in the plant species, two main groups could be identified. The highest mean concentrations of all metals (except for Pb) were found in onions. In all plants the mean concentrations of Cd and Pb were considerably higher than limits stated in international guidelines for human consumption. The levels of the metals in onions exceeded these limits. Moreover, the Cr concentrations in mint and basil and the Zn concentrations in tarragon and parsley were higher than the established limits.     

滦河流域鲫鱼体内重金属分布及风险评价

采集滦河流域鲫鱼样本并分析重金属元素(Cu、Zn、Cr、Pb、As、Cd)在其体内的分布特征及食用风险。实验结果表明鲫鱼体内重金属含量由高到低顺序为ZnCrCuPbAsCd,蓄积器官主要为肝脏和鳃部,Cu和Cr主要蓄积在肝脏,Zn、Pb、Cd主要富集在鳃部,As的蓄积器官随地域变化,而且下游样本中各组织器官重金属含量下游高于上游。针对鲫鱼肌肉的评价表明,Zn、Cr、Pb含量超出《无公害食品水产品中有毒有害物质限量》(NY5073—2006)、《食品污染物限量》(GB2762—2012)和《食品中锌限量卫生标准》(GB 13106—1991)规定的标准限值,超出倍数依次为Cr(3.34)Pb(2.24)Cd(1.15)。基于目标危险系数法(THQ)评价结果表明鲫鱼肌肉组织单一重金属THQ值均小于1,As导致的健康风险最高,Cr最低;总风险系数(TTHQ)显示下游的溯河(TTHQ=1.263)与陡河(TTHQ=1.381)存在食用风险,风险比重较高的元素是As、Pb、Zn。     

Assessment of drain water receiving effluent from tanneries and its impact on soil and plants with particular emphasis on bioaccumulation of heavy metals

In the present study, impact of tannery and other industrial effluents on the physico-chemical characteristics of loamy drain water and their consequent impact on soil and plants irrigated with effluent have been studied. The study reveals most of the parameter pH, BOD5 and COD at sampling station I was higher than station II. Waste water quality at both Stations I and II exceeded prescribed limits (BIS) for safe disposal of effluents into the surface water Samples of soil and vegetables from the land irrigated with loamy drain water has been collected and analyzed for Cu, Zn, Ni, Cr Pb and Cd. The different metals showed different enrichment factor for loamy drain water irrigated soil and are as follows: Cd 30% (max), Pb 26%, Zn 18%, Cr 5%, Cu 5%, Ni 2% (min). For plant samples collected at polluted sites are Ni 46% spinach (whole plant) (max), Zn 42% spinach (whole plant), Cr 39% spinach (whole plant), Cu 33% spinach (whole plant), Pb 20% potato tuber, Cd 20% potato tuber (min). The levels of Zn 145, Cu 5.25, and Ni 39.25 microg/ g in spinach, Pb 29.25, Cr 38. 25 and Cd 3.2 microg/g in potato tuber grown on polluted soil irrigated with contaminated drain water were found more than the reference value, which may create chronic health hazard problem to human and cattle through food chain in long run. Accumulation of toxic heavy metals may be build up in the agriculturally productive land where it is treated with contaminated effluent enrich with metals in turn bio-concentrated in the edible fodder/plants.     

Assessment of human health risks from heavy metals in outdoor dust samples in a coal mining area

Jharia (India) a coal mining town has been affected by the consequences of mining and associated activities. Samples of outdoor fallen dust were collected at different locations of Jharia covering four different zones: commercial, petrol pump, high traffic, and residential areas. The dust samples were analysed for different trace elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Se, and Zn). The highest concentration of the elements in the dust samples are Mn (658 mg/kg), Zn (163.6 mg/kg), Cr (75.4 mg/kg), Pb (67.8 mg/kg), Ni (66 mg/kg), Cu (56.8 mg/kg), Co (16.9 mg/kg), As (4.1 mg/kg), and Cd (0.78 mg/kg). The concentration of selenium was below detection limit. Except Cd, contents of all the other elements in the dust samples were significantly lower in the residential area. High amount of Ni (145 mg/kg) and Pb (102 mg/kg) was observed in the high traffic and petrol pump areas, respectively. The exposure risk assessment strategies are helpful in predicting the potential health risk of the trace elements in the street dust. Selected receptors for risk assessment were infants, toddlers, children, teens, and adults. The calculated hazard quotient (HQ) for lifetime exposure was <1.0 for all the elements studied, indicating no risks from these elements for adults Among the receptors, toddlers were found to be more vulnerable, with HQ for Co, Cr, and Pb > 0.1. The finding predicts potential health risk to toddlers and children.     

Assessment of heavy metals in water,sediment, Anabas testudineus and Eichhornia crassipes in a former mining pond in Perak,Malaysia

The concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn and Zn were analysed in water, sediment, muscle of climbing perch fish (Anabas testudineus), and tissue of water hyacinth plants (Eichhornia crassipes) collected from a former tin-mining pond in Perak, Malaysia. The monitoring was performed during the minimum and maximum rainfall periods. The concentrations of As, Cr, Fe, Ni, Pb and Zn in water exceeded the permissible limits set by the Interim National Water Quality Standards for Malaysia (INWQS). The risk index (RI) values determined for As, Cd, Cr, Cu, Hg, Pb and Zn in sediment presented a low degree of ecological risk. The order of the top three heavy metals measured in fish muscle was Zn?>?Fe?>?Al. The estimated daily intake (EDI) of As and Cr exceeded the allowable limits in both rainfall periods. The bioconcentration factor (BCF) and translocation factor (TF) values of Zn in water hyacinth were 24.865 and 3.214, respectively. The concentrations of Cu and Zn in the plant tissue were significantly correlated (p?<?.05) with the concentrations of heavy metals in water. Overall, climbing perch and water hyacinth are excellent bioindicators of environmental impacts on water bodies.     

Assessment of As and Heavy Metal Contamination in the Vicinity of Duckum Au-Ag Mine, Korea

In order to assess the potential of As and heavy metal contamination derived from past mining activity and to estimate the human bioavailability quotients for As and heavy metals. Tailings, soils and crop samples were collected and analysed for As, Cd, Cu, Pb and Zn. The mean concentrations of As, Cd, Cu, Pb and Zn in the tailings were 68.5, 7.8, 99, 3,754 and 733 µg g^–1, respectively. Maximum Pb concentration in tailings was up to 90 times higher than its tolerable level. The concentrations of these metals were highest in the soils from the dressing plant area, and decreased in the order: farmland soil to paddy soil. In particular, some of the soils from the dressing plant area contained more than 1% of Pb and Zn. The pollution index ranged from 0.19 to 1.93 in paddy soils, and from 1.47 to 3.60 in farmland soils. The average concentrations of heavy metals in crops collected from farmland were higher than those in rice stalks or rice grains, and higher than the internationally accepted limits for vegetables. Element concentrations extracted from farmland soils within the simulated human stomach for 1 h are 9.4 mg kg^–1 As, 3.8 mg kg^–1 Cd, 37 mg kg^–1 Cu, 250 mg kg^–1 Pb and 301 mg kg^–1 Zn. In particular, the extracted concentrations of Cd, Pb and Zn are in excess of the tolerable levels. The results of the simple bioavailability extraction test (SBET) indicate that regular ingestion (by inhalation and from dirty hands) of soils by the local population could pose a potential health threat due to long-term toxic element exposure.     

Heavy metal contamination in soils and food crops around Dabaoshan mine in Guangdong,China: implication for human health

This study was designed to investigate heavy metal (Cu, Zn, Pb, and Cd) contamination levels of soils, vegetables, and rice grown in the vicinity of the Dabaoshan mine, south China. The concentration of Cu, Zn, Pb, and Cd in paddy soil exceeded the maximum allowable concentrations for Chinese agricultural soil. The heavy metal concentrations (mg kg⁻¹, dry weight basis) in vegetables ranged from 5.0 to 14.3 for Cu, 34.7 to 170 for Zn, 0.90 to 2.23 for Pb, and 0.45 to 4.1 for Cd. The concentrations of Pb and Cd in rice grain exceeded the maximum permissible limits in China. Dietary intake of Pb and Cd through the consumption of rice and certain vegetable exceeded the recommended dietary allowance levels. The status of heavy metal concentrations of food crops grown in the vicinity of Dabaoshan mine and their implications for human health should be further investigated.     

Heavy metal pollution in various canals originating from river Yamuna in Haryana

Heavy metal pollution due to Fe, Ni, Pb, Cd, Co and Zn in the water of major canals originating from the river Yamuna in Haryana was studied. All these metals except Zn were found to be present in the Western Yamuna Canal (WYC) exceeding the maximum permissible limits. In the Sunder branch (SB), the heavy metal concentration was relatively more. Concentrations of the metals were, however, relatively less in the highly eutrophicated waters of Agra canal and Gurgaon canal as compared to that in WYC but Fe concentration were much higher. Except Zn and Ni the metal concentrations exceeded the standard permissible limits in these canals also.     

Investigation and risk assessment modeling of As and other heavy metals contamination around five abandoned metal mines in Korea

Tailings, agricultural soils, vegetables and groundwater samples were collected from abandoned metal mines (Duckum, Dongil, Dongjung, Myoungbong and Songchun mines) in Korea. Total concentrations of arsenic (As) and heavy metals (Cd, Cu, Pb and Zn) were analyzed to investigate the contamination level. Several digestion methods (Toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), 0.1 N/1 N HCl) and sequential extraction analysis for mine tailings were conducted to examine the potential leachability of As and heavy metals from the tailings. The order of urgent remediation for the studied mines based on the risk assessment and remedial goals was suggested. The Songchun mine tailings were most severely contaminated by As and heavy metals. Total concentrations of As and Pb in the tailings were 38,600–58,700 mg/kg (av. 47,400 mg/kg) and 11,800–16,800 mg/kg (av. 14,600 mg/kg), respectively. Agricultural soils having high As concentrations were found at the all mines. Average concentrations of Cd in the vegetables exceeded the normal value at all mines areas, while As only at the Dongjung, Myoungbong, and Songchun mine area. One groundwater sample each from the Dongil and Myoungbong mines, and 4 groundwater samples from the Songchun mine had values above 10 μg/L of As concentration. The TCLP method revealed that only Pb in the Songchun tailings, 6.49 mg/L, exceeded the regulatory level (5 mg/L). Employing the 1-N HCl digestion method, the concentration of As in the Songchun mine tailings, 4,250 mg/kg, was up to 3,000 times higher than its Korean countermeasure standard. Results from the sequential extraction of As in the tailings showed that the easily releasable fraction in the Myoungbong and Songchun mine tailings was more than 30% and the residual fraction was less than 40%. Based on results showing the exposure health risk employing the hazard quotient and cancer risk of As, Cd and Zn, the Dongil mine needs the most urgent remedial action. The concentration reduction factor (CRF) of As in both soil and groundwater follows the order: Songchun>Dongjung>Dongil>Myoungbong>Duckum mine.     

宝山堇菜多金属吸收特征和耐性策略

宝山堇菜Viola baoshanensis Shu,Liu et Lan是一种Cd超富集植物,但它对不同重金属的吸收和转运能力有待进一步研究。从湖南桂阳宝山多金属矿区中筛选4个宝山堇菜优势分布的小生境,分析这些生境中宝山堇菜及其根区土壤的重金属质量分数。化学分析结果显示,宝山堇菜优势分布土壤中Cd、Pb、Zn、Cu、Mn和Fe的平均质量分数（mg/kg）分别为471、15 044、8 273、1 776、4 702和69 054。宝山堇菜地上部Cd、Pb、Zn、Cu、Mn和Fe的平均质量分数（mg/kg）分别为387、1 077、1 037、99、379和1 812,其中Cd、Pb超过超富集植物标准,Zn、Cu的平均质量分数大约是Zn、Cu超富集植物标准的10%,Mn的平均质量分数低于Mn超富集植物标准的5%,Fe的平均质量分数高于1 000 mg/kg。上述结果表明,宝山堇菜可以超富集Cd和Pb,富集Zn、Cu和Fe以及低积累Mn。此外,宝山堇菜对不同重金属差别化吸收模式可能也代表了超富集植物适应重金属复合污染土壤的一种策略。     

Concentrations of cadmium,manganese, copper,zinc, and lead in the tissues of the oyster (Crassostrea iredalei) obtained from Setiu Lagoon,Terengganu, Malaysia

Heavy metals pollution in aquatic environments is a major problem contributing to human health issues. The study of these pollutants through bioindicators such as the oyster Crassostrea iredalei is important for (1) determining the levels and sources and (2) regulating the quantity of pollutants. The concentrations of cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), and lead (Pb) in tissues of C. iredalei, sediment and surrounding water was measured, and data was analyzed to determine the relationship between sampling periods and between oyster tissue, sediment, and water. The highest concentration of metals in oyster tissue was Zn, followed by Cu, Mn, Cd, and Pb. Concentrations of Cd, Cu, and Zn exceeded the maximum level allowed according to the Malaysian Food Act of 1983, which is equivalent to the WHO recommended levels of heavy metals in organisms used for consumption. The highest metal concentration in sediment was Mn followed by Zn, Pb, Cu, and Cd. Concentrations of heavy metals in surrounding water were Zn, Pb, Cu, Mn, and Cd. There was no correlation between metal concentration in oyster tissue and in sediment for all five metals.     

粤北星子河水生生物体内重金属污染特征及健康风险

本文分析了粤北星子河12种水生生物样品中Cd、Cr、Cu、Pb、Ni和Zn等6种金属元素的含量水平。利用综合污染指数法和目标危害系数法对水生生物中重金属的污染特征及其健康风险进行评价。结果表明:不同水生生物对重金属的富集程度存在明显差异,重金属的含量水平从低到高顺序依次为:CdNiPbCrCuZn;鱼类富集重金属明显低于贝类。在贝类样品中,Cr、Pb和Zn的含量均出现超标现象。鱼类重金属综合污染指数低于1,属于微污染;而田螺重金属综合污染指数大于1,属于轻度污染水平。不同鱼类中重金属的复合健康危害系数(TTHQ)均小于1,且每周评估摄入量(EDI)均远低于暂定每周允许摄入量(PTWI),居民通过鱼类摄入重金属的健康风险较低;田螺中重金属对人的复合健康危害系数大于1,长期食用田螺存在较高的健康风险,风险较高的重金属元素为Cr、Pb和Zn。     

Heavy metal contamination and human health risk assessment in drinking water from shallow groundwater wells in an agricultural area in Ubon Ratchathani province, Thailand

Most local people in the agricultural areas of Hua-ruea sub-district, Ubon Ratchathani province (Thailand), generally consume shallow groundwater from farm wells. This study aimed to assess the health risk related to heavy metal contamination in that groundwater. Samples were randomly collected from 12 wells twice in each of the rainy and the dry seasons and were analyzed by inductive coupled plasma spectrometry-mass spectrometry (ICP-MS). The concentration of detected metals in each well and the overall mean were below the acceptable groundwater standard limits for As, Cd, Cr, Cu, Hg, Ni and Zn, but Pb levels were higher in four wells with an overall average Pb concentration of 16.66 ± 18.52 μg/l. Exposure questionnaires, completed by face-to-face interviews with 100 local people who drink groundwater from farm wells, were used to evaluate the hazard quotients (HQs) and hazard indices (HIs). The HQs for non-carcinogenic risk for As, Cu, Zn and Pb, with a range of 0.004–2.901, 0.053–54.818, 0.003–6.399 and 0.007–26.80, respectively, and the HI values (range from 0.10 to 88.21) exceeded acceptable limits in 58 % of the wells. The HI results were higher than one for groundwater wells located in intensively cultivated chili fields. The highest cancer risk found was 2.6 × 10^?6 for As in well no. 11. This study suggested that people living in warmer climates are more susceptible to and at greater risk of groundwater contamination because of their increased daily drinking water intake. This may lead to an increased number of cases of non-carcinogenic and carcinogenic health defects among local people exposed to heavy metals by drinking the groundwater.     

Regional ecotoxicological hazards associated with anthropogenic enrichment of heavy metals

Regional geochemical data of heavy metals are commonly used for environmental risk assessment and management. Often these data are based on so-called total concentrations, whereas the exposure to the mobile or reactive fraction of these elements finally determines whether the exposed ecosystem is at risk and to which extent. The objective of our research was to develop a wider applicable method for quantitative hazard assessment of soil metal contamination attributable to the activity of man, based on and illustrated with data from the Netherlands. Since chemical availability (0.43 M HNO3 extractable concentrations) of Cd, Cu, Pb and Zn appeared strongly related to the estimated anthropogenic enrichment, we used these concentrations to assess the hazard of human-induced enrichment of these metals. We expressed the enrichment hazard using the toxic pressure concept, which estimates the fraction of biological species (varying between 0 and 1) potentially affected due to the level of exposure to single metals or their local mixtures. This is done using logistic (enrichment) concentration/response models parameterized with ecotoxicological effect data from toxicity tests and mixture models. Hazards varied from very low toxic pressures (lower than 0.01) to (most often) toxic pressure less than 0.05, whereby the latter relates to the so-called 95%-protection criterion used in some soil protection legislations. In rare cases, the toxic pressure exceeded the value of 0.05, to an upper limit of 0.054 for Cd. The rank order of metal enrichment hazards suggests that Cd enrichment induces the largest hazard increase. There are limited (rank order) differences in enrichment hazards between soil types. Comparing the judgement of soils based on soil screening levels and based on toxic pressure of anthropogenic Cd, Cu, Pb and Zn enrichments, the soil screening values appear to more conservative. This exemplifies the use of soil screening values as a method to note regulatory concern, but not always indicating an actual hazard or risk. When screening values are exceeded, refined hazard insights can be obtained, as illustrated in this paper. This provides a more refined insight in the ecotoxic implications of human-induced metal enrichments in soils, as refined basis for risk management decisions.     

Metals and metalloids in PM10 in Nandan County,Guangxi, China,and the health risks posed

Intense mining, smelting, and tailing activities of polymetallic ore deposits have affected the environment in Nandan County, Guangxi, China. Samples of particulates with aerodynamic diameters low or equal 10 μm (PM₁₀) were collected in Nandan County to investigate the concentrations of and health risks posed by 17 metals and metalloids in the PM₁₀. The metal and metalloid concentrations were lower than those found in other industrial cities. The mean Cr concentration was 7.48 ng/m³. Significant higher metal and metalloid concentrations were found in PM₁₀ from mining areas (Dachang and Chehe) than from the control area (Liuzhai) (p < 0.05). Principal component analysis indicated that the main sources of Ba, Co, Cr, Fe, K, Mg, Mo, Na, and Sr were resuspension of the soil produced through mineral erosion, the main sources of As, Cd, Cu, Pb, Sb, and Zn were smelting and mining activities, and the main source of Ni was fossil fuel combustion. Higher non-carcinogenic and carcinogenic risks were posed in Dachang and Chehe than in Liuzhai. The non-carcinogenic risks posed to adults and children by individual metals and metalloids in PM₁₀ at all the sites were low, but the non-carcinogenic risks posed to children by all the metals and metalloids together exceeded the safe level (i.e., risk value > 1). The carcinogenic risks posed by Cd, Ni, and Pb were negligible at all sites, while As, Co, and Cr posed potential carcinogenic risks to the residents.

     

铅锌矿区周边耕地土壤团聚体重金属污染状况及风险评估

为了解铅锌矿区耕地土壤团聚体污染状况,以贵州省都匀范家河铅锌矿区周围耕地土壤为研究对象,研究土壤团聚体中镉(Cd)、铅(Pb)、锌(Zn)3种重金属垂直分布特征和赋存形态。采用三步连续提取法(BCR)对污染土壤团聚体中3种重金属进行赋存形态分析,利用分布因子法(DFx)和地质累积指数法(Igeo)评估其环境风险。结果表明:土壤样品中重金属Cd、Pb和Zn的平均质量分数分别为23.25、518.40、3471.83 mg·kg^-1,已分别达到贵州土壤背景值的35.23、36.35、14.73倍,且3种重金属在土壤团聚体中的含量与其主要赋存形态特征均存在明显差异。研究区域剖面土壤中各粒径Cd主要以残渣态和可还原提取态的形式存在,各粒径Pb主要以残渣态和可氧化提取态的形式存在,80%及以上各粒径Zn为残渣态,综合得出研究区域土壤中重金属潜在影响程度为Cd>Pb>Zn。分布因子法结果表明:在0-100 cm剖面深度,Cd主要富集在0.25-1 mm的颗粒中,Pb主要富集在1-2 mm的颗粒中,Zn主要富集在0.053-2 mm的颗粒中;地质积累指数法结果显示,各粒径颗粒中Cd、Zn的污染水平主要为重污染,Pb主要为偏重污染。研究矿区周围耕地土壤已受到严重的重金属污染,应采取有效措施进行修复治理。该文为范家河铅锌矿区环境风险评价提供基础,旨在为矿区环境管理提供数据支撑。