Trace Elements in Street and Household Dusts in Amman,Jordan

This research aims at quantifying the concentrations of heavy metals within the home environment in Amman, the capital city of Jordan, and to compare the total concentrations of indoor dusts to that of exterior dusts and soils. Housedust samples were collected from different zones of Amman. Street dust samples and garden soil samples were collected in the immediate vicinity within 10–50 m of each residence. The geometric mean concentrations of metals in the household dust were Pb, 169 mg/kg; Cd, 2.92 mg/kg; Zn, 1985 mg/kg; Cu, 133 mg/kg; Cr, 66 mg/kg; Co, 21 mg/kg; Ni, 31 mg/kg; Mn, 284 mg/kg; Be, 3.0 mg/kg; Ba, 43 mg/kg; B, 697 mg/kg and Al, 1441 mg/kg. Comparisons of household dust, garden soil and street dust were based on the same particle size fraction. Results showed housedust samples to contain higher concentrations for Pb, Zn, Cr, Ni, Cd, Cu and B, than either street dust or garden soil samples. However, the differences between Pb and Cr levels in the three different sample categories were insignificant. Enrichment factor calculations and the enrichment factor ratios indicated that patterns of enrichment of indoor dust differ from that of exterior dusts.     

Using plane tree leaves for biomonitoring of dust borne heavy metals: A case study from Isfahan,Central Iran

Limited studies have been conducted on atmospheric dust pollution due to high cost of instrumental monitoring and difficulties in associated sampling methods. In this study, the possibility of using leaves of plane tree (Platanus orientalis L.) as a bioindicator of atmospheric pollution was evaluated by determining the composition of heavy elements in both the tree leaves and the atmospheric dust. Plane tree leaves were sampled monthly for 7 consecutive months (May to Nov.; T₁–T₇) from 21 different sites in the city of Isfahan, central Iran. Atmospheric dust samples were also collected from the same sites on glass trays simultaneously, except for T₁. Concentrations of Cu, Fe, Mn, Ni, Pb, and Zn were determined in both the washed (WL) and unwashed leaves (UL) as well as in the atmospheric dust samples. Elemental concentrations in the dust samples deposited on the leaves were determined by subtracting metal concentrations in UL from those in WL. Significant amounts of heavy metals were detected in UL taken from all sites at all the sampling times except for T₇ before which time a heavy rain had fallen. Statistically significant correlations were found between the heavy metal concentrations in the atmospheric dust and the dust deposited on the leaves (UL–WL) except for Pb in T₄ and T₅ sampling times. The spatial distribution maps of heavy metal concentrations in atmospheric dust followed almost the same pattern as those in plant leaf dust. The results showed that plane tree leaves have a great potential for use as an indicator of air pollution for all the heavy metals investigated except for Pb. This passive dust sampling and pollution accumulating method appears to be an easy, inexpensive, and accessible approach for the detection of atmospheric heavy metals.     

Health risk assessment on heavy metals in urban street dust of Tianjin based on trapezoidal fuzzy numbers

The aims of this article were to investigate heavy metals concentrations in urban street dust of Tianjin, to examine spatial variations of heavy metals pollution, and to assess their health risk to local populations. Urban street dust samples were collected from 144 typical crossroads in an urban area of Tianjin. Levels of heavy metals were determined by atomic absorption spectrophotometer analyzer. Given comprehensive consideration of the complexity and uncertainty of health risk assessment, trapezoidal fuzzy number was introduced to assess the health risk of heavy metals in the urban street dust of Tianjin. The results showed that the pollution of heavy metals in the urban street dust of Tianjin was serious. The relatively serious metal pollution tended to be located in the center, north, northeast, and southeast of the study area. The research indicated that heavy metals in street dust had caused non-cancer hazard to children but had not caused non-cancer or cancer hazard to adults. The direct ingestion of dust via hand-mouth contact behaviors was the major exposure pathway for health risk.     

沈阳市住宅区小区与街道灰尘重金属污染评价

城市住宅区是人类活动的重要场所,与居民的日常生活紧密相关。为了解沈阳市住宅区小区与街道灰尘中重金属污染的空间分布,采集了不同住宅区小区与街道的灰尘样品,分析了灰尘中重金属的含量,并使用富集因子和地累积指数评估了其污染程度。结果表明,沈阳市灰尘中重金属Cr、Cd、Cu、Pb和Zn的平均含量均超过辽宁省表层土壤元素背景值。单因素方差分析表明,街道灰尘中重金属Cu、Fe、Mn和Zn的空间分布具有显著性差异,而小区灰尘中重金属Cd、Cr、Fe、Mn和Pb在空间上具有显著性差异。重金属Cd、Zn和Pb的平均污染水平较高,其中小区内Cd和Zn的污染程度高于街道。沈阳市不同方位住宅区灰尘中重金属的污染水平介于轻度污染至中度污染之间。     

Spatial patterns,hotspot, and risk assessment of heavy metals in different land uses of urban soils (case study: Malayer city)

A study on identification of hotspots, spatial patterns, and risk evaluation of heavy metals in urban soils of Malayer city (Iran) was carried out. Fifty-nine composite surface soil samples were collected from six different land uses (urban parks, streets, and squares, boulevards, residential and agricultural areas) in Malayer city, and the total heavy metals were measured by atomic absorption spectroscopy. Average concentrations of Cd, Pb, Cu, and Zn, As, Cd, and Pb were 0.66, 15.51, 12.25, and 96.8 mg/kg, respectively. Among the six land uses, heavy metal contamination was heavier for street, while low contamination could be found for residential and urban parks. The spatial distribution of Pb in surface soil was similar to those of Cd, and Cu was similar to those of Zn with decreasing values from the central areas to the suburb. Also, there were several hotspots for studied heavy metals that Cd and Pb were mainly occurred in locations of heavy traffic in the city center and Cu and Zn in the west and northwestern in the city. The calculated result of risk evaluation showed that much of the city suffered from moderate to severe pollution by four of these heavy metals.     

北京城区行道树国槐叶面尘分布及重金属污染特征

叶面尘分布范围广、累积时间长,能够较好地指示近地面大气颗粒物污染特征和累积状况。为揭示城市道路交通的大气颗粒物污染特征,研究了北京城区不同类型道路两侧行道树国槐(Sophora japonica)的叶面滞尘量,分析了叶面尘主要重金属的浓度和污染特征,采用相关分析和主成分分析法探讨了颗粒物重金属的主要来源。结果表明:国槐叶面滞尘量在快速路、主干路、次干路、支路上的比值为100∶84∶75∶75,受车流量影响较大。行道树国槐的平均叶面滞尘量为0.68 g/m2,庭院树国槐(远离交通)叶面滞尘量是0.51 g/m2,两者差异显著。行道树叶面尘重金属元素Cu、Zn、Pb在叶面尘中的浓度达到土壤背景值的6倍,空间分布较均匀,主要来自交通排放,庭院树叶面尘重金属污染也受到交通排放的重要影响。     

杭州市六种常见绿化树种叶片累积空气重金属特征及与环境因子的相关性

该研究选取杭州市2个污染区常见的6种绿化树种叶片作为材料,以清洁区为对照,采用电感耦合等离子体发射光谱法,测定受试树种叶内及对应样点降尘、土壤中Pb、Cd、Cr、Cu、Ni和Zn的含量,分析叶片的吸污能力以及重金属含量与土壤、降尘的相关性。结果表明:(1)污染区树种重金属含量明显高于对照区,绿化树种对环境重金属污染物有一定的吸收能力,重金属含量在不同的树种中具有明显差异;所测树种叶内Zn含量最大,Pb次之,Cd最小,指示能力则以枸骨(Ilex cornuta)对Cd和Pb、圆柏(Juniperus chinensis)对Cu、茶花(Camellia japonica)对Ni、广玉兰(Magnolia grandiflora)对Zn为最强。(2)3个样点树种叶片与对应样点土壤、降尘中重金属元素含量的相关性分析和回归分析表明,叶片重金属含量与土壤重金属含量的相关性较小,而与降尘呈显著正相关。因此,绿化树种叶片作为空气重金属污染的累积器和监测器是科学合理的,且上述4种树种对杭州市空气中6种重金属污染的指示作用具有一定参考价值,可作为监测城市空气质量的特型树种。该研究结果为减少城市空气重金属污染提供了科学依据和理论支持。     

Heavy Metal Contamination of Soil,Plant and Air of Scrapyard of Discarded Vehicles at Zarqa City,Jordan

Ninety soil samples, forty plant samples (Anabasis articulata), and twenty air samples were collected from the scrap yard of discarded vehicles near Zarqa city, Jordan. These samples were analyzed for heavy metals: Cd, Pb, Zn, Cu, Mn, Al, and Fe. Longitudinal and vertical profiles of soil samples were studied. Generally, the levels of all heavy metals studied in the scrap yard area were found to be higher than those of the control samples. The levels of heavy metals decreased with depth until reaching a constant value at 9 cm depth. The levels of heavy metals also decreased at distances farther away from the scrap yard area. A significant difference in heavy metal concentrations was found between washed and unwashed plant samples. On the other hand, no significant differences have been found between plant samples from inside and outside the scrap yard area. Air samples showed wide variations in heavy metal levels among the sampling sites. The enrichment factors for non-crustal elements such as Pb, Cd, Cu, and Zn, in both soil and particulate matter, were found to be more than 10, indicating anthropogenic sources such as dust, rust, and exhaust emissions from the scrap yard area, whereas the crustal elements such as Fe and Mn showed enrichment factors of less than 10.     

城市地表灰尘中重金属的来源、暴露特征及其环境效应

地表灰尘是城市环境重金属的“源”、“汇”载体,与环境质量和人类健康有着密切关系.分析了城市地表灰尘重金属污染研究的意义,综述了国内外城市地表灰尘重金属地球化学行为研究进展,包括地表灰尘重金属来源、暴露特征及其影响因素分析、环境效应等方面.提出应加强时间序列及小尺度微观研究;地理因素对地表灰尘中重金属暴露特征、环境效应的影响机理研究.     

Risk Assessment of Heavy Metals in Street Dust Particles to a Stream Network

Runoff with contaminated urban soil has an environmental risk to the aquatic environment. An assessment of heavy metals in street dust particles from a small town and their risks to the township stream network were conducted at Yangtze River delta. This assessment is based on measurement of heavy metal contents in dust particles with different particle sizes, river sediments, and suspended solids of urban runoff. The ranges of heavy metal content were 0.8–4.3, 16–380, 69–240, 9.3–350, 9.6–863 and 67–1170 mg/kg dry street dust, for Cr, Cu, Ni, Pb and Zn, respectively. Approximately 63%-71% of heavy metals were associated with particles less than 250 μ m; this particle size accounted for 40% of the total mass of street dusts. Of the five land use areas, the industrial areas had the highest heavy metal level. The smaller particle size fraction has a higher heavy metal content, low density, high mobility in runoff, and thus is a higher risk to the stream network. The topographical and hydrological features of the landscape also influence the transport of the contaminated street dusts to the aquatic environment.     

Simultaneous Determination of Cd, Pb, Cu, Zn, and Se in Human Blood of Jordanian Smokers by ICP-OES

A total of 73 blood samples (56 from smokers and 17 from nonsmokers) were collected to determine the concentrations of selected heavy metal in the whole blood of smokers and nonsmokers living in and around the city of Amman, Jordan. Analysis of heavy metals in the whole blood samples of various groups took in consideration the number of cigarettes smoked per day. The analysis of blood samples was carried out using inductively coupled plasma optical emission spectrometry. This study aimed to evaluate the blood metal levels in smokers and nonsmokers and to assess the influence of smoking cigarettes on blood metal levels. The results were compared with those from a control group. The results indicated that the average concentrations of cadmium (Cd), lead (Pb), copper (Cu), zinc (Zn), and selenium (Se) were 0.0313, 0.344, 2.328, 3.214, and 0.332 mg/L, respectively. Statistical analysis of results indicated that these average concentrations were significantly higher compared with the average concentrations in nonsmokers (P < 0.05). Moreover, the correlations between blood metal and other blood metal levels in smokers, the correlations between blood metal and other blood metal levels in nonsmokers, and the correlations between blood metal concentration in smokers and its concentration in nonsmokers were calculated. The standard reference material (blood serum National Institute of Standards and Technology 1598) and the quality control were used to validate the reliability of the method used for the estimation of heavy metals in blood samples. Results revealed that there was an agreement between the certified values and the measured values.     

Determination of heavy metals in the fruit of date palm growing at different locations of Riyadh

Exposure of heavy metals to human beings has risen dramatically in the last 50 years. In today’s urban and industrial society, there is no escaping from exposure to toxic chemicals and heavy metals. Humans are more likely to be exposed to heavy metal contamination from the dust that adheres to edible plants than from bioaccumulation. This is because it is very difficult to wash off all the dust particles from the plant material before ingesting them. The objectives of this experiment were to determine the concentrations of lead (Pb) and cadmium (Cd) in washing residues and in the tissues of fruits of date palm growing in 14 sites of Riyadh and also to assess whether the fruits were safe for human consumption. The washing residues and tissue of date palm fruits collected from different sites showed the presence of significant amounts of the Pb and Cd. The concentration of Pb in the dust and fruit tissue increased with increasing anthropogenic sources. Therefore, fruits of date palm might be used as a pollution indicator; it might be recommend that fruits of date palm could be safe for human consumption after washing. The mean concentration of Pb and Cd in all the samples collected from different sites is within the safe limits recommended by FAO/WHO.     

In Vitro Health Risk Assessment of Ingesting Metal-Enriched Soils and Dusts in a Chinese Mining City

To evaluate the potential health hazards caused by extensive vanadium–titanium magnetite mining, bioavailability and bioaccessibility of metals were assessed in the pluralistic mining–agriculture–residential city of Panzhihua, China. Intensive mining and related heavy traffic may have contributed to Ni, Cr, and Zn contamination and Mn and V accumulation in soils and road dusts. The metal bioavailability estimated by water extraction was significantly lower than metal bioaccessibility on the basis of the simple bioaccessibility extraction test. The bioaccessible metal concentrations were significantly and positively correlated with soil/dust total metal concentrations (p < .05). However, bioavailable metal concentrations exhibited no relationship with total metal concentrations except for V. The bioaccessibility of metals significantly varied and exhibited the following order: Pb > Zn > Mn > Ni > V > Cr. Health risk assessment indicated that the carcinogenic and non-carcinogenic risks posed by these metals were at an acceptable level, but Cr in soils of the mining area and V in surface soils along the Jinsha River were close to the safe level for children. Therefore, the potential health risk attributed to the exposure of children to metals in surface soils and road dusts in such areas should not be overlooked.     

Interaction of Soil Heavy Metal Pollution with Industrialisation and the Landscape Pattern in Taiyuan City,China

Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning.     

Size fractions of dust and amount of associated metals on leaf surface and inner wax of 15 plant species at Beijing roadside

To provide more insight into the removal ability of urban air dust and associated metals by plant leaves, and thus guide urban green planning to improve air quality, 15 plant species leaves collected from Beijing roadside were analyzed for size fractions of leaf surface dust (SD) and inner wax dust (WD). Seven associated metals Cd, Cr, Cu, Fe, Mn, Pb and Zn were also measured. Metal Accumulation Index (MAI) was calculated for different species leaves at various dust sizes and soluble forms, respectively. Cluster analysis was used for the plant species and correlations between dust and metal concentrations and for inter-metal concentrations were calculated for both surface and inner wax dust. Mean leaf total dust TD (SD?+?WD), SD and WD were measured as 1159, 817 and 342?mg m^?2, respectively, with the highest values observed all in Euonymus japonicus. Most species leaves collected larger ratios of SD than WD except Salix babylonica and Robinia pseudoacacia. While SD was presented at all particle size fractions for all plants, nearly all species leaves collected higher proportions of WD >10?µm. Mean metal levels of leaf TD of all species ranged from high to low as Fe?>?Cr?>?Zn?>?Pb?>?Cu?>?Mn?>?Cd, but with different orders for individual species. Metals were observed in all sizes of SD/WD, although the size distributions were various for certain metals. Intercorrelations of metal concentrations in leaf SD/WD were positively significant except Pb, which may have different emission sources. Species Prunus cerasifera f. atropurpurea, Syringa oblata, Malus micromalu, Koelreuteria paniculata and Robinia pseudoacacia may possess better overall metal collection ability due to their relatively higher MAI values, but species Euonymus japonicus, Malus micromalu, Ligustrum x vicaryi and Koelreuteria paniculata were identified as the best choices in removing air dust based on cluster analysis and suggested to be planted at heavy trafficked road site for air quality improvement.     

Heavy Metal Concentration in the Urban Environment of Addis Ababa,Ethiopia

This work assesses the issue of whether the measured concentrations of heavy metals in soil, rocks, surface and ground waters in Addis Ababa can be related to anthropogenic contamination or natural weathering of rocks. Heavy metal analyses of rocks, soils, streams, springs and boreholes have been carried out to identify the presence of potentially harmful solutes. The maximum concentration of total chromium measured is 269 ppm in the northern, industry-free zone of Addis Ababa in the B ₂-horizon of soil profile (cambisol). The Ni/Cr ratio in the rocks is higher than soils, which could indicate the presence of high concentrations of Cr in soils is from weathering processes. A comparative study of different samples collected from various parts of the city indicates that the chemical composition of the hydrothermally affected volcanic rocks plays an important role in increasing heavy metal concentration in the study area. The fresh country rocks contain relatively low concentrations of heavy metals, as shown by background values. The statistical evaluation indicates that the hydrothermally altered rocks contain far higher mean heavy metal concentrations than the fresh acidic rocks (background values). Consequently, soils derived from altered rocks are enriched with respect to heavy metals. From this study it was possible to observe that the rock and soil outcrops of Addis Ababa are anomalously rich in heavy metals derived from hydrothermal activity. Therefore, heavy metal concentrations in the surrounding rocks and soils are related to geogenic sources whereas anthropogenic contribution as a cause of these concentrations is minor.     

深圳市不同功能区土壤表层重金属污染及其综合生态风险评价

在综合考虑深圳市城市功能区分异特征的基础上,进行全市表层土壤系统采样,全面监测土壤表层8种重金属元素污染状况,分析不同重金属元素含量的统计学特征,探讨不同城市功能区对土壤表层重金属污染的影响,采用内梅罗指数和潜在生态危害指数评估不同重金属元素和不同城市功能区的生态风险水平,分别进行基于两种方法的全市重金属污染生态风险分区。结果表明: 1)深圳市土壤表层的Mn、Ni、Cr和Pb 4种元素受人为活动的影响程度较低,Cd、Zn、Cu和As 4类元素受人为活动影响较大。地表环境约束因素背景下的高强度城市化和工业化过程,是各种重金属污染区域分异和功能区分异的决定性因素。2)深圳市土壤重金属污染风险较高的重金属元素为Cd、Zn、Cu和Pb,特别是Pb污染问题尤为突出,必须加强管控工作。深圳市总体土壤表层重金属污染风险水平高于国内相关城市,需要引起足够重视。3)内梅罗指数法和潜在生态危害指数法的侧重点不同,在单一重金属元素风险判断、不同城市功能区生态风险的总体评价,以及市域土壤重金属污染生态风险分级评价方面结果差异较大,组合使用效果更好。     

Heavy metal concentrations in kidneys of urban gray squirrels

Concentrations of lead and zinc in the kidneys of 180 urban gray squirrels were determined by spectrophotometry and found similar for all age groups; however, concentrations of cadmium increased up to two years of age. Values for 12 rural squirrels were significantly lower than those of the urban animals. There were no differences in mean concentrations of the metals when urban squirrels were grouped by the land usage pattern of the sites in which they were captured. Grouping squirrels by human socioeconomic strata for the city revealed that squirrels in low socioeconomic areas have significantly higher levels of lead than animals residing in middle or high socioeconomic areas.     

Source identification and availability of heavy metals in peri-urban vegetable soils: A case study from China

The purpose of this study was to investigate the total and available concentrations of Pb, Cr, Cu, Ni, and Zn in the vegetable soils from the outskirts of a heavy industry city, Northeast China, and to assess the sources of heavy metals and their availability. The average concentrations of Pb, Cu, and Zn were significantly higher than their background values of Changchun topsoil. Principal component analysis, cluster analysis, and geostatistical analysis results suggested that Pb, Cu, and Zn were consistently from anthropogenic sources, while Cr and Ni were from natural sources with low concentrations. Kriging results showed that several hotspots of high metal concentration were identified by the geochemical maps and caused by different environmental factors. Although the available (ethylene-diamine-tetraacetic acid-extractable) fractions showed much lower values than total concentrations of metals, Pb and Cu had relatively high AR^a (average availability ratio of metals) values. Our findings show that most of the studied metals had accumulated to some extent in vegetable soils and several hotspots of high metal concentration appeared at the peri-urban of Changchun. The concentrations of some metals in peri-urban vegetable soils have been largely affected by anthropogenic activities. Appropriate measures should be taken to effectively control heavy metal levels in vegetable soils and thus protect human health.     

Geochemical baseline determination and pollution assessment of heavy metals in urban soils of Karachi,Pakistan

Karachi is one of the most populated urban agglomerations in the world. No categorical study has yet discussed the geochemical baseline concentrations of metals in the urban soil of Karachi. The main objectives of this study were to establish geochemical baseline values and to assess the pollution status of different heavy metals. Geochemical baseline concentrations of heavy metals were estimated using the cumulative frequency distribution (CDF) curves. The estimated baseline concentrations of Pb, Cr, Cu, Zn and Fe were 56.23, 12.9, 36.31, 123.03 and 11,776 mg kg⁻¹, respectively. The pollution status of heavy metals in urban soils was evaluated using different quantitative indices (enrichment factor–EF, Geo-accumulation Index–I_geo, and pollution index–PI). Enrichments factors of the selected heavy metals determined by using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. The urban soils of Karachi were found to have a moderate to moderately severe enrichment with Pb, whereas Cr and Cu has moderate and Zn has minor enrichment. I_geo results indicated moderate soil contamination by Pb at some of the sampling locations. PI for Pb, Cr, Cu and Zn was found in the range of 0.04–3.42, 0.19–1.55, 0.27–2.45 and 0.32–1.57, respectively. Large variations in PI values of Pb revealed that soil in those areas of the city which are influenced by intensive anthropogenic activities have exceptionally high concentrations of Pb. The findings of this study would contribute to the environmental database of the soil of the region and would also facilitate both at the local and the international scales, in a more accurate global environmental monitoring, which will eventually facilitate the development of management and remediation strategies for heavy metal contaminated urban soil.