Pollution and ecological risk assessment of antimony and other heavy metals in soils from the world's largest antimony mine area,China

Xikuangshan is located in Lengshuijiang City, Hunan province, China. With intensive mining and metallurgical activities, large amounts of tailing containing heavy metals (in this study, the term “heavy metals” is used for both metals and metalloids) were introduced to the soils around the mine area. Those heavy metals including antimony and other heavy metals would pose huge risk to human health and ecological environment. With a view to providing information on the extent of contamination and potential ecological risk of heavy metals in the soils of this mine area, the total contents of antimony (Sb), manganese (Mn), zinc (Zn), arsenic (As), cadmium (Cd), and lead (Pb) in the soils were examined. The results revealed that the predominant pollutants in this area were Sb, Cd, and Zn with mean concentrations being 356.58, 9.98, and 486.42 mg kg^?1, 119.66, 117.41, and 5.17 times of the corresponding background values respectively. The pollution indices (Ps) indicated that the pollution levels of all sampling zones were serious including the control zones. The ecological risk levels of all heavy metals were very high on all the sampling zones except sampling zone 7 (as considerable), and Sb, Cd, and As were regarded as making great contribution to the risk indices (RI).     

Source apportionment and health risk assessment of heavy metals in agricultural soils in Xinglonggang,Northeastern China

Heavy metals in soil can affect human health through the exposure pathways of oral ingestion, dermal contact, and inhalation. In this study, to assess the health risk of heavy metals in the agricultural area of Xinglonggang, 52 soil samples were collected and tested to obtain the concentrations of As, Cd, Cr, Cu, Ni, Pb, V, and Zn in the soil. The enrichment factor indicated that the heavy metals of the agricultural soils were enriched, but the degree of enrichment was mild for all of the heavy metals. Coefficient analysis and principal component analysis indicated that V, Cr, Ni, and Pb were mainly from natural sources, As was from irrigation, Cu and Cd tended to be from chemical fertilizers and pesticides, and Zn was from mixed sources including irrigation, chemical fertilizers, and pesticides. A human-health risk assessment indicated that the residents in the study area face high risk from carcinogens and low risk from noncarcinogens; As and Cr are the major heavy metals affecting human health. This study provides a reference and a basis for formulating effective measures to prevent and control heavy metal enrichment in agricultural soils.     

Pollution and health risk assessment of heavy metals in urban soil in China

The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10^?6–1 × 10^?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.     

Contamination features and health risk of heavy metals in suburban vegetable soils,Yanbian, Northeast China

In recent years, heavy metal contamination in suburban vegetable soils calls for significant concerns due to the rapid urbanization and industrialization. In present study, 110 suburban vegetable soil samples from Yanbian, Northeast China, were collected. Concentration characteristics, pollution level, health risk, and source identification were evaluated by using different quantitative indices. Concentrations of Pb, Cr, Cu, Ni, Zn, Cd, and As in suburban soils were measured. Mean concentrations of Pb, Cr, Cu, Ni, Zn Cd, and As were 34.9 ± 10.5, 73.5 ± 44.4, 29.6 ± 19.4, 23.4 ± 12.0, 88.5 ± 26.7, 0.16 ± 0.16, and 9.24 ± 3.79 mg/kg, which were showed significantly higher than corresponding background values of Jilin province, respectively. The soils were moderately heavy polluted by Cu and Cd based on the results of geo-accumulated index and pollution indices. The pollution load index indicated that almost all of the study area were middle or heavy polluted, especially in Antu County and Helong City. Children in Yanbian may pose non-carcinogenic and carcinogenic risks with the major exposure pathway of ingestion. Principle component analysis results suggested that Pb, Cu, Zn, and Cd were mainly associated with agricultural activities, Ni and Cr were defined as combined source (lithogenic and anthropogenic), and As was tended to be from excessive application of pesticides and industrial activities.     

Spatial variation of soil quality and pollution assessment of heavy metals in cultivated soils of Henan Province,China

Abstract

Eight chemical and physical characteristics and seven biological properties of the soils from five cultivated areas in the Henan Province were quantified. Concentrations of Cu, Cr, Zn and Mn were determined using the flame atomic absorption spectrometry. In addition available phosphorus, chloride, soluble salt and pH were measured. The activities of enzymes were determined by a literature method. The results showed that the concentrations of Mn, Zn and Cr had close relationships with that of available phosphorus, and their concentrations increased with the prolonged application of organic and mineral fertilisers and pesticides-fungicides. The activities of cellulase have a relationship to the concentrations of Zn and Mn at 0.95 levels respectively, Zn and Mn stimulate many enzyme activities. The relationship between protease and available phosphorus was nearly distinctive at 0.95 levels, relating with the use of nitrogen fertiliser in the farmlands. Local organic manures and urea fertilisers did not change the soil characteristics to a great extent. However, the soils showed moderate and moderate-to-strong contamination by Mn and Zn in the study areas. Wastewater and groundwater irrigation, pesticides-fungicides, and fertiliser may be responsible for the elevated concentrations of Zn and Mn in the soil samples.     

Pollution,sources, and risks of heavy metals in coastal waters of China

Abstract

Comprehensive information on heavy metals in coastal waters at national scale of China is limited. Therefore, this study investigated the distribution, pollution, and ecological-health risks of heavy metals in coastal waters along 18,000?km coastline of China. Total 13 target heavy metals in coastal waters along coastline of China showed drastic spatial variations with average concentrations ranging from .14 (Cd) to 136.26 (Cu) μg/L. Cu was the dominant heavy metal with the maximal concentration of 1485.92?μg/L. Three methods including heavy metal pollution index (HPI), Nemerow index (NI), and contamination degree (CD) were adopted to explore heavy metal pollution. HPI obtained the worst-case evaluation results to illustrate that heavy pollution occurred at over 50% of sampling sites. Anthropogenic sources were the main sources of heavy metals in the coastal waters. Approximately 28.13% and 9.38% of sampling sites illustrated considerable and very high ecological risks, respectively. Metals including Cu, As, and Hg were the main pollution and risk contributors. Heavy metals in coastal waters posed high cancer risks and unacceptable non-cancer risks to both adults and children. Therefore, effective control of heavy metals is necessary for regional sustainability and well-beings of residents in coastal regions of China.     

西安城市路边土壤重金属来源与潜在风险

应用X-Ray荧光光谱仪对西安城市路边土壤重金属含量进行测定,运用相关分析、主成分分析和聚类分析探讨了路边土壤的重金属来源,并利用潜在生态风险指数法评价了其生态风险.结果表明:西安城市路边土壤中Co、Cr、Cu、Mn、N、iPb和Zn的平均含量均高于陕西土壤背景值.路边土壤中As、Mn和N i主要来自于自然源和交通源,Cu、Pb和Zn主要来自交通源,Co和Cr主要来源于工业源.潜在生态风险评价结果显示,西安城市路边土壤中重金属元素属于中等污染程度,具有中等潜在生态风险.     

Health risk assessment of heavy metals in soils and maize (Zea mays L.) from Yushu,Northeast China

To investigate heavy metal accumulation in soils and evaluate health risk through maize consumption, a total of 196 soils and 55 maize samples were collected from Yushu, China, one of the most important maize production bases. The mean contents of Cd, Cr, Cu, Zn and Pb were 0.119, 56.51, 19.21, 70.58, and 34.42 mg kg^?1 for soils and were 0.014, 0.68, 1.33, 17.15 and 0.02 mg kg^?1 for maize, respectively. The contents of Cr, Cu, Zn and Pb in all soil and maize samples did not exceed safety thresholds, but the percentages of Cd content above guideline values of Chinese Environmental Quality Standards for Soil and maximum permissible limits for maize were 6.6% and 1.8%, respectively. The spatial distribution and correlation analysis suggested that Cr and Cu in soil were of lithogenic origin, while Zn and Pb were associated with coal combustion exhausts and chemical fertilizer application. The main source of Cd may be phosphate fertilizer application. The average target hazard quotients were all less than 1 and the average hazard index for adults was 0.065, indicating that there was not a potential health risk through maize.     

Distribution and health risk assessment of heavy metals in soil surrounding a lead and zinc smelting plant in Zanjan,Iran

One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10^?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.     

Assessment of heavy metal pollution and human health risk in urban soils of a coal mining city in East China

The aims of this study were to determine the concentrations, distribution, potential ecological risk (PER), and human health risk (Risk) of heavy metals in urban soils from a coal mining city in China. A total of 36 topsoil samples from Huainan city, Anhui, East China, were collected and analyzed for As, Hg, Pb, Cd, Cr, and Cu. The PER was calculated to assess the pollution level. The hazard index (HI) and carcinogenic risk were used to assess the human health risk of heavy metals in the study area. The average concentration of As, Hg, Pb, Cd, Cr, and Cu were 12.54, 0.21, 24.21, 0.19, 49.39, and 21.74 mg kg^?1, respectively. The correlations between heavy metals indicated that Cu, Cr, Cd, and Pb mainly originated from automobile exhaust emissions, coal gangue, fly ash, and industrial wastewater, and that As and Hg mainly came from coal combustion exhaust. The PER index values of heavy metals decreased in the following order: Hg > Cd > As> Cu > Pb > Cr. The HI and Risk values indicated that the noncarcinogenic and carcinogenic risks of selected metals in the urban soil were both below the threshold values.     

东江沉积物重金属分布特征及污染评价

采用ICP-MS对东江河流沉积物中的重金属进行分析,发现东江沉积物中Cu、Zn、Cd、Hg等重金属呈现相同的变化特点,高值区和低值区基本一致.东江流域沉积物的重金属污染物主要是Cu、Zn、Cd、Hg、Pb,其平均含量分别为157.29、213.21、0.98、0.42、50.77mg·kg-1,均高于中国大陆沉积物背景值.地累积指数法和Hakanson潜在生态危害指数法对东江流域沉积物污染程度和生态危害程度的评价结果显示,东江沉积物中地累积指数从大到小的顺序为Cd、Cu、Zn、Hg、Pb;从总的污染程度来看,东江沉积物中各重金属对生态风险影响程度从大到小的顺序为Hg、Cd、Cu、Pb、Zn;从总的生态风险指数上看,整个东江流域除处于上游的河源市段生态风险低外,处于中游的惠州段生态风险为"较高",处于下游的东莞段生态风险为"极高".     

A human health risk assessment of soil and crops contaminated by heavy metals in industrial regions,central Iran

In this study, the concentrations of heavy metal (Cd, Pb, Fe, and Ni) in contaminated soils adjacent to two steel mill companies and in three crops (i.e., wheat, rice, and onion) grown in these regions were compared with a non-industrial site in Isfahan province, central Iran. The results were manifold. The heavy metal concentrations of both the soil and crops within the two industrial regions turned out to be more significant than the nonindustrial counterpart. In addition, the soils surrounding the companies were demonstrated to be contaminated by Cd, Pb, and Ni according to the limits provided by the international standards (i.e., USEPA and European Union standards). As for the crops from the investigated contaminated sites, the mean concentrations of Cd, Ni, and Pb exceeded the maximum permissible levels for human consumption stipulated by FAO/WHO standards. Furthermore, the values gained from the target hazard quotient were above one, meaning that the crops are contaminated. Given the results gained from a comparison made between estimated daily intake and tolerable daily intake, it can be concluded that the inhabitants of the two investigated contaminated sites are at a potentially serious health risk caused by exposure to the crops contaminated with the heavy metal.     

Arsenic and heavy metals health risk assessment through drinking water consumption in the Peshawar District,Pakistan

This study aimed to assess the drinking water quality and human potential health risk in Peshawar, which is the most populous district of Khyber Pakhtunkhwa Province, Pakistan. Water was randomly collected throughout Peshawar District (urban = 45 samples and rural = 29 samples). These samples were analyzed for heavy metal (As, Cd, Co, Cu, Cr, Hg, Ni, Pb, and Zn) concentrations using the atomic absorption spectrometer (Perkin Elmer, AAS-PEA-700). Heavy metal concentrations in drinking water revealed the highest pollution index (PI) values—17.80, 11.92, 7.50, and 5.70 for the Pb, Cr, Cd, and Ni, respectively. The contaminations of Cd and Pb were significantly higher (p < .05) than their maximum allowable limits set by the World Health Organization. Heavy metal contaminations in drinking water were evaluated for health risk assessment: the chronic risk or hazard quotient (HQ) and cancer risk. Results revealed that HQ values were >1 for the Cd and Pb, suggesting that the exposed human beings could be at chronic risk. Therefore, serious measures such as drinking water treatments and contamination controlling policies are needed to avoid the hazardous effects of toxic heavy metals.     

Distribution of heavy metals in soils and vegetables and health risk assessment in the vicinity of three contaminated sites in Guangdong Province,China

Due to rapid industrialization and urbanization, human activities like industrial and agricultural production, transportation, aggravate heavy metal pollution in soil and continue to endanger vegetables and human health. In this study, three contaminated areas affected by heavy metal pollution in Guangdong Province were investigated in terms of Cu, Zn, Pb, and Cd concentrations in soil and vegetables. Further analyses of the contamination status and potential risks to the health of residents consuming these vegetables were conducted. Results showed the following average heavy metal concentrations in vegetables and soil: Shaoguan > Guangzhou > Dongguan, indicating that mining has caused massive soil-heavy metal pollution. The heavy metal concentrations and Bioconcentration factors (BCFs) showed the following trend: leaf-vegetables > fruit-vegetables > root-vegetables, and those of vegetable type were as follows: Cd > Zn > Cu > Pb. The Nemero pollution index (PI) of all research region soils and hazard index (HI) exceeded 1. Hence, more attention should be paid to the potential for adverse health effects caused by the consumption of vegetables produced in these sites . Thus, effective measures are encouraged, with a focus on children due to their vulnerability to these heavy metals.     

惠州市3座供水水库沉积物重金属污染特征

为了解惠州市供水水库沉积物重金属(Cr、Cu、Zn、Cd、Pb和Hg)污染状况和垂直分布特征,于2008年5月在惠州市3座具代表性的水库湖泊区采集柱状沉积物样品,运用ICPMS法检测沉积物中重金属含量,并采用地积累指数法(Igen)和潜在生态风险指数法(RI)进行污染评价,同时运用主成分分析(PCA)对沉积物中重金属的可能来源进行分析.结果表明:3座水库沉积物重金属含量随沉积深度的变化差异明显,一些重金属含量的垂直变化不明显,而另一些垂直变化明显(降低或升高),但各种重金属在不同水库沉积物中呈现特有的垂直分布特征.根据地积累指数可知,3座水库中沉积物主要以Zn和Pb污染最为严重,达到轻度至强度污染(含量分别为Zn:49.98 ～ 640.29 mg·kg-1;Pb:21.94～300.66 mg· kg-1),同时沉积物中部或底部受到轻度的Cu污染(含量为16.85 ～45.46 mg·kg-1),基本未受Cr、Cd和Hg污染.据6种重金属潜在生态风险系数[Er(i)]及潜在生态风险指数(RI)可知,3座水库沉积物的重金属潜在风险均处于较低水平.据PCA分析和相关资料可知,矿山开采与冶炼、城市化和农林业快速发展等人类活动影响了3座水库沉积物重金属的分布特征和污染.其中,Zn主要来源于矿产开采与冶炼;除矿产开采与冶炼导致沙田水库Pb污染外,机动车尾气排放和生活垃圾等是3座水库沉积物Pb污染的主要途径;Cu污染主要来源于农业和林业污染.     

Distribution of heavy metals in the water,sediments, and fishes from Damodar river basin at steel city,India: a probabilistic risk assessment

Abstract

The present study, deals with the estimation of degrees of contamination, ecological and human health risk of heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn) in sediments, surface water and fishes, which were collected from middle stretch of Damodar river and ponds at Asansol, which receives outfall of various coal-based industries. Metal content in the premonsoon season was higher than the postmonsoon, due to influx of rainwater. The heavy metal pollution indices (HPI) at some locations was observed up to 1.45 times than recommended value and the cadmium (Cd) was found dominating metal for high HPI value. The Cd concentration in surface water and pore water varied from 2.8 to 14.9?µg/L and 15.3–57.0?µg/L, respectively, which was up to 6 times higher than the permissible limit. Ecological risk assessment for sediments illustrates ‘moderate to considerable ecological risk’, especially because of Cd. Hazard index (HI) calculated to identify potential human health risk by dermal exposure of surface water was <0.1, indicating ‘negligible non-cancer risk’ for all age group of people. However, HI varied from 0.73 to 1.49 for adult and 1.37–2.78 by consumption of fishes indicates children have higher ‘non-cancer risk’ than adult.     

Assessment of potential health risk of heavy metals in soils from a rapidly developing region of China

Soil heavy metal contamination is a major environmental concern, and health risk associated with heavy metals is not fully explored. A combination of spatial analysis and Monte Carlo simulation was successfully used to identify the possible sources and health risk of cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), chromium (Cr), and copper (Cu) in soils collected from a rapidly developing region of China. It was found that mean concentrations of Cd (0.17 mg/kg ), As (8.74 mg/kg ), Hg (0.15 mg/kg ), Pb (27.28 mg/kg ), and Cu (33.32 mg/kg ) were greater than the soil background values. Accumulation and spatial variability of heavy metals were significantly affected by anthropogenic activities and soil properties. The risk assessment indicated that non-carcinogenic risk was not significant. However, 95% of the total cumulative carcinogenic risk of children was greater than 1E-05, implying high potential carcinogenic risk with As and Pb representing the major contributors. Ingestion of heavy metals in the soils was the main exposure pathway compared with the inhalation and the dermal exposure. Concentration of heavy metals in the soils, particulate emission factor, and dermal exposure ratio were the major parameters affecting health risk. This study highlights the importance of assessment of soil direct exposure health risk in studying heavy metal exposures.     

Geochemical speciation and ecological risk assessment of heavy metals in surface soils collected from the Yellow River Delta National Nature Reserve,China

In this study, a comprehensive assessment of soil heavy metal (HMs) pollution in the Yellow River Delta National Nature Reserve (YRDNNR) was conducted. Spatial distributions, chemical fractions, and sources of eight HMs (Cu, Zn, Pb, Cr, Cd, Fe, Mn, and Ni) in 46 soil samples in the studied region were analyzed. In addition, the potential risks of the HMs were evaluated. The results showed that the mean concentrations of Cu, Zn, Pb, Cr, Cd, Fe, Mn, and Ni were 19.4, 65.2, 38.4, 55.9, 0.078, 41546.5, 510.3, and 27.5 mg kg^?1, respectively. It indicates that the concentrations of most HMs, with exception of Pb and Fe, in samples were similar to the background value of soil in China. Principal component analysis results showed that the HMs originated mainly from natural sources, but Pb pollution in the studied area was significantly caused by anthropogenic activities. In addition, Ecological risk assessment statistical analysis indicates that the HM contamination level in YRDNNR ranged from low to moderately polluted, however, the environmental risk due to Mn and Pb contamination was high.     

重金属污染区土壤酶活性变化——以福建龙岩新罗区特钢厂污水灌溉区为例

从福建龙岩新罗区特钢厂污灌区农田采集土壤,测定土壤基本理化性质及脲酶、纤维素酶、碱性磷酸酶、多酚氧化酶、过氧化氢酶活性和Cu、Cd、Pb、Zn含量,探讨重金属污染和土壤性质对土壤酶活性的影响.结果表明:4种全量或有效态重金属与土壤脲酶、纤维素酶、碱性磷酸酶和多酚氧化酶活性呈显著正相关,与过氧化氢酶活性呈显著或极显著负相关;土壤pH与碱性磷酸酶活性呈极显著正相关,粉粒含量与过氧化氢酶活性呈显著负相关.经通径分析,重金属污染刺激了脲酶、多酚氧化酶和纤维素酶活性,但对碱性磷酸酶活性的影响较小.有效态Cu、Cd、Pb、zn对过氧化氢酶活性的直接影响并不大,但通过间接途径抑制了过氧化氢酶活性.土壤理化性质对5种土壤酶活性的影响较大,碱解氮直接抑制了脲酶活性;全磷直接刺激了碱性磷酸酶和过氧化氢酶活性,并通过有效磷刺激了纤维素酶活性;有效磷直接刺激了纤维素酶活性,直接抑制了碱性磷酸酶和过氧化氢酶活性;全钾直接抑制了碱性磷酸酶和多酚氧化酶活性;速效钾通过有效磷刺激了纤维素酶活性;土壤颗粒组成明显影响多酚氧化酶和过氧化氢酶活性.5种酶活性与土壤Cu、Cd、Pb、Zn含量之间的关系不明确,因此其活性不是指示土壤Cu、Cd、Pb、Zn污染的良好指标.     

哈尔滨市不同类型人工林土壤重金属含量

以东北林业大学城市林业示范研究基地9种人工林(兴安落叶松林、樟子松林、黑皮油松林、黄波罗林、胡桃楸林、水曲柳林、白桦林、蒙古栎林和针阔混交人工林)为对象,分析林地土壤不同层次(0～10 cm和10-30 cm)A8、Cd、Cu、Ni、Pb、Zn 6种重金属含量,并以哈尔滨市土壤背景值为标准,采用综合污染指数法评价各林型土壤重金属污染状况.结果表明:不同类型人工林同一土层重金属含量差异显著;除了As和Ni,同一人工林土壤重金属含量均随土壤深度增加呈下降趋势.各类型人工林同一土层重金属含量以Zn最高(62.29～126.35mg·kg-1),Cd最低(0.06～0.47 mg·kg-1).6种重金属含量由高到低顺序为:Zn＞Pb＞Cu(Ni)＞Ni(Cu)＞As＞Cd,累积程度为:Cd＞Pb＞Zn＞Cu＞Ni＞As.林地土壤Pb、Cd、Cu、Zn间(除水曲柳林)及其与土壤有机质、N、P、K(除水曲柳林和蒙古栎林)显著相关,且以上4种重金属含量高于背景值,为人为输入;Ni和As含量与本地背景值相当,为自然因素,不同林型土壤内梅罗综合污染指数依次为:水曲柳林＞黄波罗林＞针阔混交林＞胡桃楸林＞樟子松林＞黑皮油松林＞兴安落叶松林＞白桦林＞蒙古栎林.