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.     

Spatial distribution,contamination levels,sources, and potential health risk assessment of trace elements in street dusts of Urumqi city,NW China

Abstract

A total of 83 dust samples were collected from the streets of Urumqi city in NW China and analyzed for the concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn elements. The spatial distribution, contamination levels, main sources, and potential health risks of these trace elements were determined based on geostatistical analysis, geo-accumulation index, multivariate analysis, and the health risk assessment model introduced by the USEPA, respectively. The obtained results indicate that the average concentrations of Cd, Cr, Cu, Hg, Ni, Pb, and Zn exceed the corresponding background values determined in Xinjiang soils by factors of 2.0, 1.35, 1.38, 8.24, 1.28, 2.09, and 3.26, respectively. The spatial distribution patterns of the nine trace elements in street dust were found to be substantially heterogeneous, and the contamination level decreased in the following order: Hg?>?Zn?>?Pb?>?Cd?>?Cr?>?Cu?>?As?>?Ni?>?Mn. Based on the identified concentrations, the collected dust samples were found to be moderately polluted by Hg, and not polluted by As, Cr, Cu, Mn, and Ni. The remaining elements, Cd, Pb, and Zn lie on the borderline between non-pollution and moderate pollution levels. Furthermore, it was shown that Mn and Zn in street dusts originate from both, natural and anthropogenic sources, while As, Cd, Cr, Cu, Hg, Ni, and Pb are mainly produced by anthropogenic sources. Overall, the carcinogenic and non-carcinogenic health risks of the analyzed elements, instigated primarily by oral ingestion of street dusts, were found to be within the acceptable range for both, children and adults. As and Cr are the main non-carcinogenic elements, whereas Cr is the major carcinogenic element among the investigated dust-bound metals in the study area.     

Human health risk assessment of trace elements in shallow groundwater of the Linhuan coal-mining district,Northern Anhui Province,China

Enrichment of trace elements in groundwater poses considerable risks to human health. The concentrations of seven trace elements (Cr, Mn, Ni, Cu, Zn, Cd, and Pb) in 34 samples of shallow groundwater from the study area were estimated. We assessed the concentrations of the trace elements and health risks with statistical analysis and the US Environment Protection Agency (USEPA) model. The results showed that the mean concentrations of trace elements decreased as follows: Mn > Zn > Ni > Cr > Cu > Cd > Pb. Apart from Mn at one sampling point, the concentrations of all trace elements were below the guideline values of the World Health Organization for drinking water. Correlation and cluster analysis indicated that the trace elements fell into groups, with Ni and Cu in one group, and Mn, Zn, and Cd in another, which suggested that the trace elements grouped together had similar sources. The total non-carcinogenic risk values ranged from 8.52 × 10^?4 to 1.27 × 10^?1. The total carcinogenic risk caused by Cr and Cd averaged 1.62 × 10^?6, which exceeded the acceptable level of 1 × 10^?6 recommended by the USEPA. The carcinogenic risk of Cr accounted for 75.93% of R_total.     

Sources and risk assessment of toxic elements in the agricultural soil of Tiantai County of Zhejiang province,China

Abstract

The aim of this study was to quantify the pollution level of toxic elements, their ecological risk and human health hazard in the agricultural soil of Tiantai County, Zhejiang province. A total of 2651 soil samples were collected and analyzed for 13 toxic elements using different analytical techniques. The concentration of Cd, Pb, Hg, Mn, and Zn was higher than the Zhejiang background value in more than 50% of samples. Enrichment factor showed that As, Cd, Hg, Mo, Pb, Se, V, and Zn were anthropogenically loaded and most of the toxic elements showed poor spatial distribution. Nemerow pollution index showed that Chicheng, Shiliang, Pingqiao, Tantou, and Youngxi towns were seriously polluted by toxic elements. Principal component analysis and cluster analysis showed that Co, Cr, Ni, and Cu, whereas, Cd, Pb, and Zn shared the similar source of origin. A large area of Tiantai County experiencing moderate to a serious level of pollution but most of the toxic elements exhibit low risk to the environment except Cd and Hg. Furthermore, children were more prone to health hazards than adults with following order: As?>?Cr?>?Pb?>?Mn. Overall, As and Pb were prominent for pollution, ecological risk, and human health hazards.     

Environmental quantification of soil elements in the catchment of hydroelectric reservoirs in India

The contamination of inorganic elements in soil is a serious environmental problem,. The aim of the present study is to investigate concentrations of 19 elements in order to access the extent of their contaminations in the surface soil of hydroelectric catchments, Uttarakhand, India. For analysis, 168 soil samples were divided into eight groups according to altitudes. In soil samples, the concentration levels of Cr and Cu were found more than their background and threshold limit. Moreover, the evaluation of geochemical index (I_geo), enrichment factor (EF), and contamination factor (CF) suggests that soil samples were reasonably contaminated and highly enriched in Rb. The pollution load index (PLI) and degree of contamination (Cd) revealed that the presence of contaminations (PLI: 1.44; Cd: 44.94) in the study site might be a possible health risk for local residents. However, the calculation pollution ecological risk index (PERI) suggests low ecological risk (PERI: 77.61) of these elements. The clustering of sampling groups contained two clusters: the first cluster comprised F1 and F4 while the second cluster consists of the rest of the sampling group. Multivariate statistical analysis revealed that the variation in concentrations of the elements might be a result of agricultural activities and pedological processes.     

Exposure assessment of potentially toxic trace elements via consumption of fruits and vegetables grown under the impact of Alaverdi's mining complex

This study is aimed to investigate the transfer of potentially toxic trace elements from soils to plants grown under the impact of Alaverdi's mining complex and assess the related dietary exposure to local residents. Contamination levels of potentially toxic trace elements (Cu, Ni, Pb, Zn, Hg, As, Cd) in soils and plants were determined and afterwards, transfer factors, estimated daily intakes, target hazard quotients, and hazard indexes were calculated.

Some trace elements (Pb, Zn, Cd) exceeded the maximum allowable levels. EDIs of Cu, Ni, Hg for the majority of studied fruits and vegetables exceeded the health-based guideline values. Meanwhile, in case of combined consumption of the studied food items, the estimated cumulative daily intakes exceeded health-based guideline values not only for the aforementioned trace elements but also for Zn in the following sequence: Zn > Hg > Ni > Cu. HI > 1 values highlighted the potential adverse health effects for local population through more than one trace element.

Detailed investigations need to be done for the overall assessment of health risks, taking into consideration not only adverse health effects posed by more than one toxic trace element but also through other exposure pathways.     

Characterization and human health risk assessment of trace metal in PM10 in Bac Giang,short-term study in a developing province in Vietnam

Abstract

This study investigated the airborne concentration of PM₁₀ and 20 trace elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Na, Pb, Ti, V, Zn) in residential, industry, traffic road, coal mining, thermal power plant area of Bac Giang province. The average PM₁₀ concentration was highest at coal site, followed by traffic 1 sites, industrial sites and traffic 2 sites, the residential sites, and lowest at the power plant site located in mountain area. While Al, Ca, Fe, K, Mg, Na were the most abundant elements in all sampling sites, accounting for 73–96% of total obtained elements, the concentration of As, Cd, Cr, Cu, Mn, Ni, Pb, V, and Zn occupied from 2.9 to 23.2%. Noticeably, the concentrations of Cd were from 7 to 65 times higher than the concentration limit for Cd (0.1?ng/m³) according the World Health Organization (WHO). Although, the Hazard Index (HI values) of all metals were found to be within the safe level for both children and adults, the Carcinogenic Risk (CR) of Cr and As in all sites were closed to the acceptable levels for children, implying a potential carcinogenic risks of these metals.     

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.     

Bioaccessibility and health risk assessment of rare earth elements in Porphyra seaweed species

In this study, the content and bioaccessibility of rare earth elements (REEs) in Porphyra spp. Samples before and after thermal treatments were investigated. Additionally, the risks of REEs exposure to human health were assessed. REEs content significantly reduced after thermal processing (P < 0.01), and the removal rate of REEs was approximately 30%. Thermal treatment increased REEs bioaccessibility from 44% to 64.34%. The concentration and bioaccessibility of Ce, La, Y, Nd were high in raw and thermally treated Porphyra samples, and there was no correlation between REEs content and bioaccessibility. Based on the following parameters: highest content of REEs in the studied seaweed samples (13.45 mg/kg), the highest daily seafood consumption (44.9 g/day), and the highest bioaccessibility (64.34%), the ratio of the calculated daily intake (DI) to daily allowable intake by diet (DAI_diet) of REEs did not exceed the reference value in rare earth mining areas or under extreme conditions. The DI via seafood consumption would be exceeded when the content of REEs in the seafood sample is greater than 15.77 mg/kg. In this study, the concentration of REEs did not exceed 15.77 mg/kg in any sample. Thus, the human health risks of REEs associated with seafood are low.     

Probabilistic risk assessment of inhalation of nickel-rich soil particulates on Jeju Island,Korea

The soils of Jeju Island contain naturally abundant nickel originating from prehistoric volcanic activity. Nickel is a known human carcinogen via inhalation exposure. A risk assessment of soil particle inhalation was conducted for the first time in Korea through the analysis of soil and air data obtained from agricultural sites. Sixteen sites in Jeju were selected—13 farms, 2 citrus orchards, and 1 ranch. Forty-four soil samples were taken from these sites and analyzed for nickel content. Total suspended solids (TSP) and particulate matter up to 10 µm in size (PM10) were measured directly from the agricultural sites, and nickel concentrations in TSP and PM10 were quantified for use in the inhalation risk assessment. We conducted a probabilistic inhalation risk analysis using monitoring data obtained from the 16 sites on Jeju Island. Risk assessment procedures followed both the Korean Ministry of Environment and the U.S. Environmental Protection Agency (USEPA) risk assessment methodologies. The cancer risk associated with inhalation followed by application of the Korean risk assessment approach ranged from 4.98 × 10^?9 to 3.43 × 10^?7, whereas the cancer risk associated with inhalation followed by application of the USEPA risk assessment approach ranged from 3.40 × 10^?9 to 3.74 × 10^?7. This study demonstrates that no carcinogenic risk is associated with inhalation in Jeju, based on a lower cancer risk limit of 10^?6.     

Risk assessment of population exposure to toxic trace elements via consumption of vegetables and fruits grown in some mining areas of Armenia

Consumption of unsafe food is one of the most important public health concerns. Trace elements’ contamination caused by direct or indirect activities of mining industries is of importance in this respect. The present study was conducted to assess the chronic dietary exposure and related health risks of trace elements through the intake of selected vegetables and fruits grown under the impact of mining industry in Syunik region (Armenia). Consumption data were obtained via food frequency questionnaire and the concentrations of Cu, Mo, Ni, Cr, Pb, Zn, Hg, and Cd in different fruits and vegetables were determined. Moreover, by combining concentration data with consumption data, estimated daily intake, and target hazard quotient were assessed for each element. The results obtained showed that mean concentrations for Pb and Hg in some vegetables exceeded maximum acceptable levels set by international organizations. Hazard indexes > 1 have been obtained in some cases indicating that for some vegetables (particularly for potato, carrot, maize, onion leaf, grape, bean, beet, sweet pepper, eggplant, and tomato) habitual consumption has a potential to pose adverse health effect to the local population.     

Dietary exposure and risk assessment to trace elements and iodine in seaweeds

IntroductionSeaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.MethodsThe aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.ResultsCadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.DiscussionNew maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury.     

桉树人工林地土壤酶活性与微量元素含量的关系

运用典范相关分析研究了桉树人工林地土壤酶活性和土壤微量元素含量关系。结果表明,Zn和Mn对土壤蛋白酶活性的促进作用最大。Zn在一定程度上对脲酶和过氧化氢酶有抑制作用;而Mn对脲酶和过氧化氢酶有促进作用。结合林地生物的生长特征等因子,"综合土壤酶因子"可作为土壤肥力评价的一个指标,对桉树林地土种的划分有一定意义。     

湘南某矿区蔬菜中Pb、Cd污染状况及健康风险评估

通过采集湘南某矿区周边农田中种植的蔬菜和对应耕作层土壤样品,探究了农田蔬菜Pb、Cd的污染状况,蔬菜和土壤重金属含量之间的相关性,蔬菜中重金属对人体的健康风险。结果表明:(1)污染区土壤重金属污染非常严重,叶菜类蔬菜重金属超出了食品卫生标准限值,但是果菜类蔬菜中重金属没有超出食品卫生标准限值。(2)不同蔬菜不同器官所含Pb、Cd有明显差异;不同种类蔬菜Pb、Cd含量不同,一般是叶菜类果菜类;同种蔬菜不同部位重金属含量的顺序也不同,一般为根茎叶果,或根叶茎果。(3)二类蔬菜中重金属Pb、Cd的富集系数顺序为叶菜类果菜类。(4)蔬菜中Pb、Cd含量与土壤中相对应元素含量均无显著相关性。(5)就农产品安全性而言,果菜类蔬菜比叶菜类蔬菜更适合在此矿区栽培。     

Health risk assessment of some heavy metals in urban community garden soils of Baghdad City,Iraq

The objective of this study is the evaluation of health risk of heavy metals in soils of urban community gardens of Baghdad City in Iraq. The soil samples were collected from 14 community gardens and analyzed for Cd, Cr, Cu, Ni, Pb and Zn. The non-carcinogenic hazard index (HI) and carcinogenic risk index (RI) were utilized to evaluate human health risk of heavy metals. The health hazard evaluation showed that there is no non-carcinogenic hazard in light of the fact that the HI values were beneath the threshold value (HI < 1). The HI for children and adults has a descending order of Cd < Cr < Cu < Ni < Pb < Zn. The carcinogenic RI values for Cd, Cr and Ni were over the unacceptable threshold value (RI < 1 × 10^?4), demonstrating that there is a serious carcinogenic risk for children and adults in the study area. The carcinogenic RI for children and adults has a descending order of Cr < Cd < Ni. These findings give environment administrators and leaders data on whether therapeutic activities are required to decrease exposure.     

Assessment of water quality and health risks for toxic trace elements in urban Phewa and remote Gosainkunda lakes,Nepal

The concentration of 13 metals (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Pb, and Hg) and their associated health risk assessment was performed for two Himalayan lakes, urban Phewa and remote Gosainkunda, from Nepal. Water Quality Index (WQI), Metal Index (MI), Hazard Quotient (HQ), Hazard Index, and Cancer Risk were calculated in order to evaluate the water quality of these lakes. Correlation analysis revealed that Mn and Fe were derived from natural geological weathering processes and Pb, V, Cr, Co, Ni, Cu, Zn, and Cd might have originated from anthropogenic sources. The results revealed that WQI of the remote lake fell into excellent water quality and urban lake fell into poor water quality, which is also supported by the MI calculation. Moreover, the HQ of Mn in urban lake showed values greater than unity suggesting its health risk to the local inhabitants. The cancer index values indicated “high” risk due to Cr, whereas Cd possesses “very low” cancer risk on local population residing nearby areas. This study provides the useful database and suggests for the regular assessment and policy formulation for safeguarding the natural water bodies in the region.     

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.     

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.     

Health risk assessment of volatile organic compounds in urban areas

The atmosphere is the first medium containing hazardous compounds entering the living environment. Metropolitan areas contain many industrial complex areas with high emissions of volatile organic compounds (VOCs), and consequently also large-scale exposure groups. As respiration is the most important part of the human exposure pathway, the atmosphere should be treated with greater importance than other media. It is therefore very important to monitor the emission of hazardous air pollutants (HAPs) and measure the concentration of VOCs in the atmosphere of such areas. It is essential to establish basic measures in order to protect public health as part of overall national safety management. This study utilized the national air pollution monitoring network data from Seoul, Incheon, and Gyeonggi, and investigated the differences in risk levels for humans considering various factors of the receptors, including gender and age. A total of 13 VOCs were categorized into carcinogens and noncarcinogens for risk assessment. The carcinogens 1,3-butadiene and benzene demonstrated a high level of cancer risk, ranging between 10^?4 and 10^?6, respectively. Noncarcinogens did not exceed Hazard Quotient (HQ) 1 in any area. The results will serve as important references for managing urban air environments and setting air quality standards.     

不同利用强度下绿洲农田土壤微量元素有效含量特征

以地处极端干旱背景下的塔里木盆地南缘策勒绿洲为研究区,以绿洲化为视角,根据当地农民耕作习惯于2005年选择4块试验农田,分别代表当地典型的农田利用强度。基于单项指数(Ei)和综合指数(Ec)相结合的评价方法,分析了绿洲农田在不同利用强度下的土壤Fe、Cu、Mn、Zn等微量元素有效性,探讨了土壤微量元素与人为耕作管理措施之间的关系。结果表明:人为耕作管理强度会对土壤微量元素有效含量产生重要影响,绿洲不同位置农田因施肥强度和管理方式的差别,其土壤微量元素有效含量特征存在显著差异。绿洲内部农田土壤有效Fe、Cu、Mn、Zn含量显著高于绿洲边缘各样地,新垦农田土壤有效Fe、Cu、Zn含量均低于对照样地;绿洲内部农田土壤微量元素有效性最高,新垦农田最低;农田土壤微量元素有效性与土壤有机质存在显著的正相关关系。