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With the fast development of industrialisation, the environment has been exposed to various elements which are hazardous. The soils are found to be the major sink of variety of contaminants. Most important of these contaminants are heavy metals. The study aimed to investigate heavy metal soil profile from five locations of an agricultural field in vertical direction. The study area chosen is village Salarpur in Tehsil Tijara, District Alwar, Rajasthan, India. Presence of Heavy metals is also compared at two depths i.e. 0 to 1 cm and 1 to 5 cm at each location. Zn, Pb, Cd, Cu, As, Fe, and Ni concentrations in the soil samples were determined using inductively coupled plasma mass spectrometry ICP-MS. Cr III was estimated by spectrophotometric method. The study of the area reveals that Total Zn, Total Pb, Total Cu, Fe and Ni content in soil decreases with depth at locations 1, 2, and 3 but increase with depth at locations 4 and 5. Total Cd content of soil increases with depth at location 1, 2, 3, and 4 but decreases with depth at location 5. The non-uniform distribution of Total Zn, Total Pb, Total Cu, Fe, Cd and Ni contents with depth is revealed. Concentration of Cr-III of soil increases with depth at all locations. Strong positive correlation of Zn with Pb, Cu, Fe and Ni, Pb with Cu, Fe and Ni, Cu with Fe and Ni, Fe with Ni is revealed at both the depths i.e. 0-1 cm and 1-5 cm. [ABSTRACT FROM AUTHOR]

Due to rapid urbanization and industrialization that occurred in Al- Muthanna province in southeastern Iraq during the last decade, pollutants such as heavy metals were emitted into the environment and became a serious threat to human health. Environmental pollution could be caused by different types of pollutants, which come from different sources. This study aims to assess the environmental magnetism efficiency for heavy metal pollution assessment using the magnetic susceptibility technique which became a more rapid and cost-effective compared to conventional methods. Increasing heavy metal contents in soils causes an increase in the magnetic mineral concentration. The study area is located in Al- Muthanna province, southeast of Iraq, and contains three cement plants, an oil refinery, bricks factories, and power plants. Fifty topsoil and subsoil samples (0-50 cm depth) were collected from five sites; Al- Jinoob cement plant (one site), Samawa oil refinery (two sites) and Al- Muthanna cement plant (two sites). In this study, magnetic properties of samples in vertical sections and levels of heavy metal elements; of selected samples from regions with different geological settings were compared. The heavy metals analysis included chromium (Cu), iron (Fe), nickel (Ni), copper (Cu), Arsenic (As) and lead (Pb), which could give indications of heavy metal pollution in soil. The highest magnetic susceptibility value (65.23 x10-8 m3kg-1) was recorded in Al-Muthanna cement plant (TSL-4) and the highest Cu concentration (602.57 ppm) was also recorded in Al- Muthanna cement plant (TSL-5-3). The results of magnetic properties show the dominance of coarse magnetite, which is supposed to have originated from pedogenic particles in natural soils, causing the positive correlation between magnetic susceptibility (χ) and anhysteretic remanent magnetisation (ARM). According to the results of frequency dependent susceptibility ratio (κfd%), the magnetic particles showed an admixture of multi-domain and pseudo-single domain behaviour. Magnetic susceptibility and heavy metal analyses results indicated emissions from nearby industrial plants. X-ray fluorescence (XRF) was carried out for heavy metal analyses which supported our results. Results of this study demonstrate the suitability of applying magnetic techniques for assessing environmental situations. [ABSTRACT FROM AUTHOR]

Human activities such as industrialisation, urbanisation and agriculture have adversely impacted terrestrial and aquatic ecosystems. Water pollutants such as heavy metals and nanoparticles can undergo bioaccumulation and bioaugmentation. Heavy metals cannot be degraded and are hence added permanently. Nanoparticles are a potential threat because of their small size and unique properties. This article reviews the impact of various pollutants on aquatic biota and presents remediation methods. Benthic macroinvertebrates can be used as bioindicators to study the impact of pollutants on aquatic ecosystems. Fishes occupy the highest trophic level in the aquatic food chain and can therefore accumulate large amounts of metal from water, ultimately leading to biomagnification. Some organic compounds such as pesticides and fungicides are carcinogenic and sometimes resistant to degradation. [ABSTRACT FROM AUTHOR]

The composition of soil water under coniferous forests of Murmansk oblast—an industrially developed region of northern Russia—was investigated. The studied objects were dwarf-shrub-green-moss spruce forests and dwarf-shrub-lichen pine forests on Al-Fe-humus podzols (Albic Rustic Podzols) that are widespread in the boreal zone. The concentrations and removal of organic carbon performing the most important biogeochemical and pedogenic functions were estimated. The results proved significant intra- and inter-biogeocenotic variability in the composition of atmospheric depositions and soil water. Carbon removal with soil water from organic and mineral horizons within elementary biogeoareas (EBGA) under tree crowns was 2-5 and 2-3 times (in some cases, up to 10 times) greater than that in the intercrown areas, respectively. The lowest critical level of mineral nitrogen (0.2 mg/L) was, as a rule, exceeded in tree EBGAs contrary to intercrown areas. Concentrations of sulfates and heavy metals in water of tree EBGA were 3-5 times greater than those in inter-crown areas. Significant inter-biogeocenotic variations related to differences in the height of trees and tree stand density were found. It is argued that adequate characterization of biochemical cycles and assessment of critical levels of components in soil water of forest ecosystems should be performed with due account for the intra- and inter-biogeocenotic variability. [ABSTRACT FROM AUTHOR]

Industrialization and urbanization are the main sources of pollutions worldwide and particularly in developing countries. This study aims the determination of anthropogenic inputs with trace metals in aquatic ecosystems at the Plain of Annaba (NE Algeria), which is known as one of the largest industrial areas in Africa. Samples of surface waters and upper sediments were conducted in six stations: four in Meboudja wadi and two in Seybouse wadi. Contents of iron, copper, chromium, nickel, zinc, and manganese were measured by atomic absorption spectrophotometry, whereas Cd and Pb were determined using electrothermal atomic absorption spectrometry. Measurements of Hg were carried out using atomic fluorescence. Spatiotemporal variations of metal concentrations were tested using generalized linear models (GLM), whereas the influence of water pollution on sediment contamination was tested with generalized additive models (GAMs). Metal contents measured in surface water and sediments varied differently from upstream to downstream of the study wadis and between seasons. The results showed that the surface water was polluted with high levels of iron, nickel, chromium, lead, and cadmium. Values of the contamination index revealed that the surface sediments were contaminated by iron, chromium, lead, and cadmium. The GAMs indicated that water-phase metal concentrations had no significant effects on trace metal concentrations in the sediment. This suggests that seasonal metal concentrations in water phase, which are measured during the study period (2012) and are time-dependent, contribute increasingly and gradually over time-not immediately-to the accumulation of metals into the sediments. Therefore, the long-term accumulation of metals in the sediments resulted from the continuous discharges of metals in the water phase. The anthropogenic impacts are marked by high contaminations of Meboudja wadi particularly in downstream areas of the steel factory and the nearby industrial areas. The direct industrial discharges into the water and atmosphere (iron, lead, cadmium) as well as urban disposals and agricultural activities are at the origin of these contaminations. [ABSTRACT FROM AUTHOR]

A major threat to the comfort of human life has been imposed by increased industrialization and urbanization. The generation and disposal of huge amounts of toxic materials and pollutants have heavily contaminated our environment. Some Organics such as synthetic dyes (SD) and heavy metals (HM) are becoming increasingly prevalent as the most dangerous pollutants in soil and surface water environments. They are causing great concern worldwide due to their toxicity to many life forms. Environmentally friendly utilization of agricultural by-products/waste materials either as raw materials or in production of so-called activated carbons (AC) is an important issue. Because it is apparent from our literature review that the main factors characterizing these materials are their affordability, local availability, and efficiencies in removing many unwanted toxics and pollutants, they therefore could be utilized instead of more conventional but expensive adsorbent materials, particularly in developing countries where many industries lack appropriate individual sewage treatment systems; even where they exist, they lack satisfactory functioning and maintenance because of the lack of good budgets. A number of case studies are supplied in this review. These case studies have pointed to the efficient removal of SD/HM ions from aqueous solutions by the agricultural by-products/wastes in the form of a raw material, signifying spent tea leaves (STL) as a good example. Besides, the efficient removal of such ions by AC produced from these agricultural by-products/wastes has also been given in detail, suggesting a variety of AC agricultural by-products/wastes sources. Both kinds are widely used adsorbents in the treatment of wastewaters. Our review has shown that these adsorbents are characterized by many exceptional physical and chemical features that make them widely used adsorbents in the treatment of wastewaters. The adsorption efficiencies by these substances were also affected by the characteristics of AC, which depend on the physical and chemical properties of the precursor (i.e., agricultural by-products/wastes) as well as on the activation method applied, which is either chemical or physical. The structural properties of the resulting AC can be affected by a number of factors such as time of activation, temperature of activation, and the oxidizing agent used in addition to the starting precursor. [ABSTRACT FROM AUTHOR]

Due to the advent of the industrialisation phenomenon, the increasing contamination of the soil caused by heavy metals has recently become a major concern. The present study set out to collect samples from the 0-30 and 30-60 cm depths of the soils in industrial areas for the purpose of evaluation of the contamination caused by the heavy metals through the Pearson correlation coefficients and quantitative indices. The results revealed that the Cu and Pb concentrations were higher than the average in both depths of shale like Cd at the 30-60 cm depth. Ni and Cd as well as Ni and Cu were shown to be higher in terms of the concentration values than the Iranian standard at the 0-30 and 30-60 cm depths, respectively. The mean I-geo soil was classified as uncontaminated by the Iranian standard, uncontaminated to slightly contaminated, and very contaminated to severely contaminated by the shale average associated with Pb, Cr and Cd, respectively, whereas Ni and Cu were determined to be uncontaminated. Low and moderate contamination factors were attributed to Pb, Cr, Cd as well as Ni and Cu by the Iranian standard at both depths. It was also shown that the mean contamination degree (CD) and modified contamination degree (MCD) were moderate and very low, respectively. The pollution load index was demonstrated to be uncontaminated by the Iranian standard. The mean contamination factor correlated with the average shale turned out to be classified as low, moderate, and very high factor as far as Fe, Cr and Ni, Pb and Cu, Cd were concerned, respectively. Moreover, the mean contamination degree (CD) and modified contamination degree (MCD) were considerable, low and moderate, respectively. The mean pollution load index was indicative of contamination, and Enrichment factor (EF) was ranked as follows: Cd > Pb > Cu (at both depths of the average shale). Correlation values (r) attested to the common sources of Pb, Cr and Ni, on the one hand, and Cr, Cu, Ni and Cd, on the other hand, at the 0-30 cm depth. [ABSTRACT FROM AUTHOR]

Industrialization and urbanization have led to a deterioration in air quality and provoked some serious environmental concerns. Fifty-four samples of atmospheric deposition were collected from an emerging industrial area and analyzed to determine the concentrations of 11 trace elements (As, Cd, Cu, Fe, Hg, Mn, Mo, Pb, Se, S and Zn). Multivariate geostatistical analyses were conducted to determine the spatial distribution, possible sources and enrichment degrees of trace elements in atmospheric deposition. Results indicate that As, Fe and Mo mainly originated from soil, their natural parent materials, while the remaining trace elements were strongly influenced by anthropogenic or natural activities, such as coal combustion in coal-fired power plants (Pb, Se and S), manganese ore (Mn, Cd and Hg) and metal smelting (Cu and Zn). The results of ecological geochemical assessment indicate that Cd, Pb and Zn are the elements of priority concern, followed by Mn and Cu, and other heavy metals, which represent little threat to local environment. It was determine that the resuspension of soil particles impacted the behavior of heavy metals by 55.3%; the impact of the coal-fired power plants was 18.9%; and the contribution of the local manganese industry was 9.6%. The comparison of consequences from various statistical methods (principal component analysis (PCA), cluster analysis (CA), enrichment factor (EF) and absolute principle component score (APCS)-multiple linear regression (MLR)) confirmed the credibility of this research. [ABSTRACT FROM AUTHOR]

A verity of human activities i.e. urbanization and industrialization have been resulted serious environmental contaminations by heavy metals in all over the world. The settlement of populations in urban and nearby industrial areas for economic development has significant share in their exposure to these metallic contaminants. Depending on the nature and type of the pollutants, targeted urban-industrial environments can have harmful and chronic health risk impacts on exposed local inhabitants and may require detoxification, healing and remedial therapy. Consequently, environmental monitoring as well as human health risk assessments of urban environments under industrial influence are key dominant features. We believe this work will provide new insights into the studies of metals exposure and associated health risks in emerging industrials cities of developing countries. Present study aimed to study the bioavailability of metals, quantify the changeability in soil and vegetable metal concentrations and estimation of human health risks via dietary exposure, focusing on urban-industrial environment. Soil and vegetable samples were collected in six random sites within the urban, periurban and industrial areas and analyzed for metal concentrations. In addition, risk assessment model proposed by US-EPA was employed to estimate the potential health risk of heavy metals via dietary intake. Results indicated that the heavy metal concentrations were noteworthy in periurban and urban-industrial areas. However, contamination levels varied with the type of vegetable, and the point source pollution such as traffic, urban wastes and industrial effluent. According to the estimated THQ and HI values for non-carcinogenic risk, little or no negative impact of heavy metals was observed on local inhabitants. However, the concentrations of Cr, Cd, Pb and Ni were nearly closed to the permissible limits described by US-EPA in urban-industrial areas. Conclusively, some efficient remedial strategies should be focus to overcome the increasing levels of Cr, Cd, Pb and Ni in this study area to protect the health of local inhabitants. [ABSTRACT FROM AUTHOR]

Human activity goes hand in hand with urban and industrial development. It leads to the emergence of new industrial technologies, construction materials and techniques. Metropolitan and urban areas are most susceptible to this influence both during the development of new territories and the operation of existing industrial and residential complexes. The article presents the results of the soil investigation conducted in the city of Novokuybyshevsk to determine prospects for future growth of the city. Soil samples were retrieved in the urban area of Novokuybyshevsk in full compliance with the requirements of the State Standard. Soil testing was performed to obtain research data on the concentrations of heavy metals (lead, zinc, copper, cadmium, nickel, manganese etc.), oil, sulfates and nitrates. The findings were then compared with the results obtained in previous years. The research provided a perspective on the current state of the soil, considered major sources of pollution and helped assess the extent of urban soil contamination in Novokuybyshevsk. Realistic and urgent measures were suggested to improve the state of the soil for further development and expansion of the industrial and residential areas of the city. [ABSTRACT FROM AUTHOR]

The human population boom, urbanization and rapid industrialization have either directly or indirectly resulted in the serious environmental toxification of the soil-food web by metal exposure from anthropogenic sources in most of the developing industrialized world. The present study was conducted to analyze concentrations of Cd, Cr, Cu, Mn, Ni, Pb, and Zn in soil and vegetables in the urban–periurban areas influenced by emerging industry. Vegetables and their corresponding soil samples were collected and analyzed for heavy metals contents from six random sites. According to the results, the potential health risks from metals to the local communities were assessed by following the methodology described by the US-EPA. In general, the total non-carcinogenic risks were shown to be less than the limits set by the US-EPA. However, the potential risk of developing carcinogenicity in humans over a lifetime of exposure could be increased through the dietary intake of Cd, Cr and Ni. In some cases, Pb was also marginally higher than the safe level. It was concluded that some effective remedial approaches should be adopted to mitigate the risks of Cd, Cr, Ni and Pb in the study area because these metal levels have exceeded the safe limits for human health. However, new studies on gastrointestinal bioaccessibility in human are required to heighten our understanding about metals exposure and health risk assessment. [ABSTRACT FROM AUTHOR]

Soil heavy metals and their bioaccumulation in agricultural products have attracted widespread concerns, yet the transfer and accumulation characteristics of heavy metals in different soil–crop systems was rarely investigated. Soil and crop samples were collected from the typical agricultural areas in the Yangtze River Delta region, China. The concentrations of Cu, Pb, Zn, Cd and Hg in the soils, roots and grains of rice ( Oryza Sativa L. ), wheat ( Triticum L. ) and canola ( Brassica napus L .) were determined in this study. Transfer ability of heavy metals in soil-rice system was stronger than those in soil-wheat and soil-canola systems. The wheat showed a strong capacity to transfer Zn, Cu and Cd from root to the grain while canola presented a restricting effect to the intake of Cu and Cd. Soil pH and total organic matter were major factors influencing metal transfer from soil to rice, whereas soil Al 2 O 3 contents presented a negative effect on heavy metal mobility in wheat and canola cultivation systems. The concentration of Zn and Cd in crop grains could well predicted according to the stepwise multiple linear regression models, which could help to quantitatively evaluate the ecologic risk of heavy metal accumulation in crops in the study area. [ABSTRACT FROM AUTHOR]

The impact of uncontrolled industrialization and urbanization on surface water and groundwater qualities was assessed in a heavily industrialized district of Kocaeli (Turkey) considering source, types and levels of contaminants. A sampling campaign was conducted on both water bodies in dry (September) and wet (May) sampling periods. Water samples were taken from 6 surface water stations and 24 wells distributed from upstream to downstream along Dil stream to determine the degree of deterioration in water quality from background conditions. Results showed that Dil stream was heavily polluted with regard to many parameters including Al, Fe, Mn, Pb, DO, COD, NH, NO and PO. While sewage discharges, leachates from closed wild landfill and quarries create sources of contamination for Dil stream at upstream, primarily metal industries (mainly iron and steel manufacturing) at downstream contribute markedly to the metal contamination. Contribution of highly polluted Dil stream to the groundwater contamination is also significant in the alluvium aquifer at both upstream and downstream of Dil stream. Microbial pollution indicating fecal contamination and high nutrient levels exist in the groundwater. In addition, relatively high AOX concentrations over background levels were detected in wells at the downstream part of Dil stream where industrial activities were densely distributed. Deep wells located near the Gulf of İzmit were also affected by seawater intrusion. Results suggest that Dil stream contaminated by industrial discharges, sewages, and leachates from old wild landfill negatively influences the groundwater quality in the alluvial aquifer. [ABSTRACT FROM AUTHOR]

Urbanization and industrialization have resulted in contamination of soils with heavy metals and other pollutants. Nickel (Ni) is one of the toxic metals, which adversely affect plant growth by altering different physiological and metabolic processes. Mineral nutrients can reduce toxic effects of Ni on physiological and metabolic functions of plants, thus improving plant growth. The role of calcium (Ca) to alleviate Ni toxicity in rice was investigated. Rice plants were grown with Ni (20 and 40 mg kg−1) and Ca (80 and 160 mg kg−1) in different combinations and without Ni and Ca as a control. Nickel (40 mg kg−1) significantly decreased shoot (54%) and root dry weights (54%), chlorophyll content (57%), the photosynthetic rate (two-fold), transpiration rate (34%) and stomatal conductance (39%) compared to control. Application of Ni (40 mg kg−1) increased the Ni concentration in shoots 22-fold and in roots 11-fold compared to control. Application of Ca (160 mg kg−1) reduced the adverse effects of Ni and the studied parameters improved to the maximum values compared to control. Calcium decreased the translocation of Ni towards the shoots that was evident from a lower translocation factor (42%) for the plants supplied with Ca compared to those grown without Ca (62%). The phytotoxicity induced by Ni on different growth and physiological parameters was alleviated by Ca as indicated by the minimum values of the phytotoxicity index for Ca fed plants (0) compared to those without Ca (2.6). [ABSTRACT FROM AUTHOR]

Potential contamination of the sediments in the Sebkha of Moknine (Tunisia) ecosystem was assessed by means of enrichment factors (EFs) estimated against reference sediment located ≈70 km away from the Sebkha. The use of EFs is recommended as a reliable method for heavy metal contamination assessment, provided that (1) element contents are corrected following a careful normalization procedure, and (2) the reference sediment is unaffected by anthropogenic alterations. The degree of contamination was assessed by the modified contamination degree approach. The obtained results indicated that surface sediments were enriched up to 22.9, 13.2, 5.46 and 3.19 times with Pb, Cu, Cr and Zn, respectively. Lower enrichment factors for Ni and Co suggested that anthropogenic sources were less important for these metals. The modified degree of contamination showed that the sediments in the Sebkha of Moknine have suffered significant systematic heavy metal contamination following catchment urbanization and industrialization . [ABSTRACT FROM AUTHOR]

Due to the latest industrial development, many dangerous chemicals have been released directly or indirectly which resulted in the polluted water bodies. Water rehabilitation is an alternative way to restore the quality of water, followed by the environmental management to control the waste discharge to ensure the balance of the degradation rates or detoxifying by environmental factors. However, this process consumed a lot of time and cost. Besides, most of the metal ions, especially copper which is capable to bioaccumulate in aquatic organism and at the elevated level may cause physiological and biochemical alteration which leads to mortality. Environmental monitoring is the initial step presupposed evaluating the potential toxicity of effluent gushing at its purpose to discharge, avoiding the determining effects of contaminant in water bodies. Due to the high sensitivity of the aquatic life towards dissolving toxicant, the fish has been utilized as the biological measurement (Biomarker) to indicate the existence of toxicant exposure and/or the impact towards the evaluation of molecular, cellular to physiological level. Thus, this paper gives an overview of the manipulation of fish as a biomarker of heavy metals through behavior response, hepatocyte alteration, enzymatic reaction and proteomic studies which have proven to be very useful in the environmental pollution monitoring. [ABSTRACT FROM AUTHOR]

Heavy-metal contamination in coastal areas poses a serious threat to aquatic life and public health due to their high toxicity and bio-accumulation potential. In the present study, levels of different heavy metals (Cu, Cd, Cr, Ni, Co, Pb, Zn, and Mn), their spatial distribution, geochemical status, and enrichment indices (Cu, Cd, Cr, Ni, Co, Pb, Zn) were investigated in the sediment samples from 18 coastal sites of Pakistan. The analyses of coastal sediments indicated the presence of heavy metals in order such as Cr > Zn > Cu > Pb > Ni > Mn > Co > Cd. Geo-accumulation index ( I), enrichment factor (EF), and contamination factor (CF) showed diverse range in heavy-metal enrichment site by site. Pollution load index (PLI) has shown that average pollution load along the entire coastal belt was not significant. Based on the mean effect range medium quotient, coastal sediments of Pakistan had 21 % probability of toxicity. The estimated sedimentary load of selected heavy metals was recorded in the range of 0.3-44.7 g/cm/year, while the depositional flux was in the range of 0.07-43.5 t/year. Heavy-metal inventories of 9.8 × 10-3.8 × 10 t were estimated in the coastal sediments of Pakistan. The enrichment and contamination factors (EF and CF) suggested significant influence of anthropogenic and industrial activities along the coastal belt of Pakistan. [ABSTRACT FROM AUTHOR]

China faces great challenges in protecting its soil from contamination caused by rapid industrialization and urbanization over the last three decades. Recent nationwide surveys show that 16% of the soil samples, 19% for the agricultural soils, are contaminated based on China's soil environmental quality limits, mainly with heavy metals and metalloids. Comparisons with other regions of the world show that the current status of soil contamination, based on the total contaminant concentrations, is not worse in China. However, the concentrations of some heavy metals in Chinese soils appear to be increasing at much greater rates. Exceedance of the contaminant limits in food crops is widespread in some areas, especially southern China, due to elevated inputs of contaminants, acidic nature of the soil and crop species or cultivars prone to heavy metal accumulation. Minimizing the transfer of contaminants from soil to the food chain is a top priority. A number of options are proposed, including identification of the sources of contaminants to agricultural systems, minimization of contaminant inputs, reduction of heavy metal phytoavailability in soil with liming or other immobilizing materials, selection and breeding of low accumulating crop cultivars, adoption of appropriate water and fertilizer management, bioremediation, and change of land use to grow nonfood crops. Implementation of these strategies requires not only technological advances, but also social-economic evaluation and effective enforcement of environmental protection law. [ABSTRACT FROM AUTHOR]

A total of 179 surface sediment samples from shallow waters have been collected in Catalonia (Northwestern Mediterranean) from 2002 to 2010 to analyze heavy metals (Al, Cd, Cu, Hg, Pb, V, and Zn) concentrations, organic matter content, and sediment size in order (i) to find baseline values, (ii) to investigate metal contamination trends, and (iii) to identify its spatial and temporal distribution. Highest metals concentrations were registered in the Barcelona metropolitan area and in the mouth of Besòs and Llobregat Rivers for Zn, Cu, Pb, and Cd. Mercury was also abundant in these areas but the highest record was found close to Tarragona. The concentrations agree with those reported in other studies performed in big river's mouths and industrialized areas. The absence of large industrial activity and urbanization outside Barcelona and Tarragona explains the low metal contents found at the other sampling sites. Based on enrichment factor (EF), Pb was the most enriched metal. Results will provide a useful aid for sustainable marine management in Catalonia. [ABSTRACT FROM AUTHOR]

The rapid growth of the human population and industrialization in the world has indirectly increased environmental problems such as water, air and land pollution. Amongst all, heavy metals can be considered as the most problematic pollutants. Numerous efforts have been attempted to minimize the impact of heavy metals. This chapter discusses the recent developments and technical applicability of different treatment methods for heavy metal removal. The adsorption process using various low-cost materials as the potential alternative for heavy metal removal is being highlighted and summarized. [ABSTRACT FROM AUTHOR]

An attempt has been made in this study to evaluate the groundwater quality in two industrial blocks of Ghaziabad district. Groundwater samples were collected from shallow wells, deep wells and hand pumps of two heavily industrialized blocks, namely Bulandshahar road industrial area and Meerut road industrial area in Ghaziabad district for assessing their suitability for various uses. Samples were collected from 30 sites in each block before and after monsoon. They were analyzed for a total of 23 elements, namely, Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Se, U, V, and Zn. In addition to these elements, some other parameters were also studied viz: color, odor, turbidity, biological oxygen demand, chemical oxygen demand (COD), dissolved oxygen, total dissolved solids and total suspended solid. The water quality index was also calculated based on some of the parameters estimated. Out of the 23 elements, the mean values of 12 elements, namely, Al, As, Ca, Cd, Cr, Mg, Mn, Na, Ni, Pb, Se, and U, were higher than the prescribed standard limits. The concentrations (in milligram per liter) of highly toxic metals viz., Al, As, Cd, Cr, Ni, Pb, Se, and U, ranged from 1.33–6.30, 0.04–0.54, 0.005–0.013, 4.51–7.09, 0.14–0.27, 0.13–0.32, 0.16–2.11, and 0.10–1.21, respectively, in all groundwater samples, while the permissible limits of these elements as per WHO/BIS standards for drinking are 0.2, 0.01, 0.003, 0.05, 0.07, 0.01, 0.04, and 0.03 mg L −1, respectively. The EC, pH, and COD in all samples varied from 0.74–4.21, 6.05–7.72, and 4.5–20.0 while their permissible limits are 0.7 dS m −1, 6.5–8.5, and 10 mg L −1, respectively. On the basis of the above-mentioned parameters, the water quality index of all groundwater samples ranged from 101 to 491, and 871 to 2904 with mean value of 265 and 1,174 based on two criteria, i.e., physico-chemical and metal contaminations, respectively while the prescribed safe limit for drinking is below 50. The results revealed that the groundwater in the two blocks is unfit for drinking as per WHO/BIS guidelines. The presence of elements like As, Se, and U in toxic amounts is a matter of serious concern. [ABSTRACT FROM AUTHOR]

Unfettered effluent discharge, in addition to seasonal runoffs, into Ikpoba River, have been blamed for the ever poor water quality noticed in the river. This study seeks to investigate the role of industrialization and/ or urbanization on the degraded water quality of the river. Chemical analyses of samples of the river water collected at predetermined sampling points were undertaken and the observations obtained were subjected to ANOVA, correlation, and eigenvalue analysis. Results obtained showed that each point source has its relative contribution to the overall degradation of the river water quality. In merit order, the eigenvalue analyses carried out suggests that phosphate, nitrate, cadmium, copper, iron, lead and turbidity are the most offensive factors showing values of 0.868, 0.933, 0.770, 0.503, 5.063, 0.717, 30mg/L respectively. Remarkably, surface runoffs from municipal drains channelled to stations 1 and 2 contribute significantly to the turbidity with 4.333 and 4.233mg/L respectively, whereupon urbanization and industrialization are seemingly the culprits. [ABSTRACT FROM AUTHOR]

In recent years, heavy metal contamination has become a major environmental issue in many parts of the world. Fe and Mn oxides, oxyhydroxides and hydroxides have long been recognized as scavengers playing an important role in controlling the location, mobility and bioavailability of metal contaminants in soils. Fe-Mn concretions and nodules are discrete bodies made of soil or sediment materials cemented together under the influence of Fe and Mn oxides. Here metals sorption by Fe-Mn concretions and nodules are surveyed and critical reviewed. Valuable available literature data demonstrate that the formation of Fe-Mn concretions and nodules is the most efficient and durable process for metal contaminants sequestration in the soils. The papers discussed in this review show that the application of Fe-Mn concretions and nodules, as geochemical scavengers for remediating metal contaminated soils, is strongly recommended. [ABSTRACT FROM AUTHOR]

Abstract: Due to the continuous urbanization and industrialization in many countries of the world, heavy metals are continuously emitted into the terrestrial environment and pose a great threat on human health. A detailed study was conducted to determine the concentrations of six heavy metals (Cr, Ni, Cu, Zn, Cd and Pb) in road dusts in urban parks of Beijing, and assessed the health risk of these metals for local people. The dust samples were collected from 13 different urban parks in Beijing, China. The health risk was assessed using Hazard Quotient (HQ) and Health Index (HI). The results show that the average concentrations of Cr, Ni, Cu, Zn, Cd, Pb in the dust samples are 69.33, 25.97, 72.13, 219.20 0.64 and 201.82mg/kg, respectively. The concentrations of Cu, Zn, Cd and Pb were much higher than those in the background value of Chinese soil. The assessment of health risk indicated that there were mainly three exposure pathways for people: ingestion, dermal contact and inhalation. The main exposure pathway of heavy metals to both children and adults is ingestion. The values of HQ and HI are lower than the safe level (=1), indicating no health risk exists in present condition. Meanwhile, the HI value for children is higher than that for adults, indicating that children have higher potential health risk than adults in Beijing parks. [Copyright &y& Elsevier]

Industrialization and urbanization have resulted in increased releases of toxic heavy metals into the natural environment comprising soils, lakes, rivers, groundwaters and oceans. Research on biosorption of heavy metals has led to the identification of a number of microbial biomass types that are extremely effective in bioconcentrating metals. Biosorption is the binding and concentration of adsorbate from aqueous solutions by certain types of inactive and dead microbial biomass. The novel types of biosorbents presently reviewed are grouped under fungal biomass, biomass of non-living, dried brown marine algae, agricultural wastes and residues, composite chitosan biosorbent prepared by coating chitosan, cellulose-based sorbents and bacterial strains. The reports discussed in this review collectively suggest the promise of biosorption as a novel and green bioremediation technique for heavy metal pollutants from contaminated natural waters and wastewaters. [ABSTRACT FROM AUTHOR]

Heavy metal pollution of soils has become a major concern in China as a consequence of rapid urbanization and industrialization in recent years. However, the evaluation on soil heavy metal pollution in Shenyang, the largest heavy industrial base city in China, has not yet been conducted. In this study, accumulation, chemical speciation, and vertical distribution Cu, Zn, Pb and Cd in soils were studied and pollution condition was assessed in Tiexi Industrial District of Shenyang, the largest and oldest industrial zone in Northeastern China. The results showed that in topsoil, the average concentration of total Cu, Zn, Pb, and Cd was 209.06, 599.92, 470.19 and 8.59 mg kg–1, respectively, much higher than the national threshold limit. The values of pollution index and integrated pollution index showed that the pollution level was Cd > Cu > Zn > Pb, and Cd, Cu and Zn belong to heavy pollution level. The residual, Fe and Mn oxide-bound, and organic-bound species accounted for about 90%, while carbonate-bound and exchangeable species accounted for about 10%. This study indicates that the soils in the industrial zone were widely and extremely polluted by multi-heavy metals as a result of long-term industrial activities. [ABSTRACT FROM AUTHOR]

The North Eastern region of India is undergoing industrial development at a faster rate than expected. Roads form the main system of transportation and communication owing to the hilly topography of the region. Automobiles discharge a number of gaseous and trace metal contaminants. Human activities like stone grinding, road construction and sand milling also increase the atmospheric dust and heavy metal contaminant level. These contaminants get settled on leaf surfaces at roadsides and enter in contact with phylloplane microorganisms. This study compares microorganisms on leaf surfaces of alder (Alnus nepalensis (Betulaceae)) on roadside and non-roadside environments. Two sites dominated by alder were selected. One at a busy road intersection on the National Highway no. 44 in Shillong with high traffic density (8 000-9 000 heavy vehicles/day), taken as the polluted site and the other one in a forest approximately 500 m away from the roadside considered as the unpolluted site. Analysis of phylloplane microorganisms, lead, zinc, copper, cadmium and sulphur was carried out from leaves. The bacterial population was higher at the unpolluted site. Bacterial population showed a significant negative correlation with lead, zinc, copper, cadmium and sulphur. Similarly, fungal population was higher at the unpolluted site. A total of 29 fungal species were isolated from the phylloplane of A. nepalensis (polluted site 16 species; unpolluted site 28 species). Some fungal forms like Mortierella sp., Fusarium oxysporum and Aureobasidium pollulans were dominant in the polluted site. Numbers of phylloplane fungi and bacteria were significantly reduced in the polluted site. The correlation coefficient indicated a detrimental effect of metals like lead, zinc, copper, cadmium and sulphur on the microbial community of leaf surfaces. The specificity of certain fungi to the unpolluted site may be attributed to their sensitivity to pollution. The predominance of Aureobasidium pollulans, Fusarium oxysporum and Mortierella sp. in the polluted site may be due to their resistance to pollutants in roadside conditions. [ABSTRACT FROM AUTHOR]