Bioremediation is an effective method of treating heavy metal polluted soils. The principles, advantages and disadvantages of immobilization, soil washing and phytoremediation techniques. Bangladesh is a densely populated developing country. The contamination of soil with these metals was assessed by contamination factors cf, degree of contamination dc, pollution load index pli, ecological risk factor er, potential ecological risk index. An assessment of heavymetal contamination in soils within. Heavy metals that have been identified in the polluted environment include as, cu, cd, pb, cr, ni, hg and zn.
Old orchards have more lead and arsenic in the soil because of residue from old insecticides. Chemical and metallurgical industries are the most important sources of heavy metals in the environment. Remediation of heavy metal contaminated soils is necessary to reduce the. Assessment of heavy metal pollution and health risks in. Heavy metal pollution in a soilrice system in the yangtze. Assessment of soil heavy metal contamination and remediation needs. Heavy metals are regarded as toxic trace elements in the environment. Heavy metals are known to be naturally occurring compounds, but anthropogenic activities introduce them in large quantities in different environmental compartments. Heavy metal in soil the concentration of heavy metals in the soil of perlis is listed in table 2. Currently, phytoremediation is an effective and affordable technological solution used to extract or remove inactive metals and metal pollutants from. Heavy metal contamination of soils monitoring and remediation.
Assessment of heavy metal pollution and human health risk. Soil is the central link that connects the organic, inorganic, biological and nonbiological worlds. In coal burning areas, the different contents of heavy metals as and cr in the coal have affected the emission of heavy metals into the atmosphere chen et al. The bioaccumulation factor baf was used to investigate the translocation of heavy metals in the soil crop. Assessment of soil heavy metal pollution in a former mining area before and after the end of mining activities article pdf available april 2017 with 1,552 reads how we measure reads. Heavy metal and metalloid pollution of soil, water. Pollution index indicated that urban soils were moderate to highly polluted by cd, zn, cu, and pb. The possible sources of heavy metals in the surface soils were identified with. It is a widely accepted method that is mostly carried out in situ. Globally, more than 10 million sites of soil pollution have been reported, with 50% of the sites contaminated with heavy metals andor metalloids such as arsenic table 1. Heavy metals is a general collective term, which applies to the. Pdf heavy metal contents in soil and plants at dumpsites. Soil characterization and heavy metal pollution assessment. The metals are classified as heavy metals if in their standard state they have a specific gravity of more than 5 g.
Remediation of heavy metal contaminated soils is necessary to reduce. In 1868, wanklyn and chapman speculated on the adverse effects of the heavy metals arsenic, lead, copper, zinc, iron and manganese in drinking water. European countries have a number of approaches to define risk levels associated with different concentrations of heavy metal in soil carlon et al. Following a description of the various sources and factors influencing the contents of heavy metal pollution in postcatastrophic and agricultural soils, subsequent chapters examine soil enzymes and eggs as biomonitors, lead adsorption, the effects of arsenic on microbial diversity, and the effects of. Higher igeo value for cd in soil indicated that cd pollution was moderate. Natural and anthropogenic source of heavy metals pollution. Accordingly, forty among which four were control samples soil. Soil next to busy roads may have higher lead levels because of exhaust from nowbanned leaded gasoline. Soil heavy metal pollution has become a worldwide environmental issue that has attracted considerable public attention, largely from the increasing concern for the security of agricultural products. Assessing heavy metal pollution in the surface soils of.
Pdf soils polluted with heavy metals have become common across the globe due to increase in geologic and anthropogenic activities. Plants growing on these soils show a reduction in growth, performance, and yield. Heavy metal pollution in agricultural areas owing to traffic emissions may contaminate the crops growing near the roadways. Urban sewage has been applied to arable land for several thousand years. Electroplating is the primary source of chromium and cadmium. All data in table 2 were compared with allowable limit from netherlands and china table 3 proposed by wang et al 2012, ecdge 2010 since there are no information available in malaysia on soil background values for heavy metal concentration 15. Soil pollution negatively impacts on food safety and human health. In agricultural areas, uptake of heavy metals through the soil crop system could play a predominant role in human exposure to heavy metals.
Consequently, areas that are polluted by heavy metals and possible heavy metal sources must be identified to develop pollution control policies, effective soil remediation and management. Ingestion was the main pathway of carcinogen risk to human health. The topsoil serves as the transfer interface for the accumulation of heavy metals in the air, plant, and water. The data of heavy metals contaminated soil was collected from all over the india from 1991 to 2018 as analyzed by various researchers. The trace metal in urban soil of 31 capital cities of china. Heavy metal contamination of soil results from anthropogenic such as mining, smelting procedures and agriculture as well as natural activities. Sources of soil pollution by heavy metals and their. Several methods already used to clean up the environment from these kinds of contaminants, but most of them are costly and difficult to get optimum results. Heavy metals are among the most important sorts of contaminant in the environment. Pdf assessment of soil heavy metal pollution in a former. Soil pollution by heavy metals is a problem of global concern, requiring the development of remediation technologies. Urban soil is highly influenced anthropogenic sources such as industrial an economical activities.
Different branches of industry and the road traffic have a significant impact on environmental pollution with heavy metals. Heavy metal pollution in surface soil of korba basin. A detailed investigation was conducted on the relationship between land use patterns and trace metal content in surface soils of the benue state to assess soil environmental quality. The data from 92 papers was compiled and to simply comparison, the data was uniformly converted into. In this work, the spatial, temporal, and vertical concentration variations, pollution indices, and sources of as, cr, cd, pb, hg, fe, mn, cu, zn, and ni heavy metals were studied in the surface soil of the largest coalburning area in india korba basin from 2011 to 2015. Assessment of heavy metal pollution in topsoil around. Soils in bangladesh polluted by heavy metals and metalloids have been found to be impacted by various pollution sources table1. The presence of heavy metals in food is a threat to human health. Both industrialization and geological sources have caused widespread heavy metal and metalloid pollution in bangladesh, which is now posing substantial threats to the local people. Should i worry about heavy metals in my garden soil. Assessment of heavy metal pollution and health risks in the soil.
Other heavy metals and metalloids of potential environmental significance the scope has been widened with four new chapters in section 1 dealing with toxicity in soil organisms, soil plant relationships, heavy metals and metalloids as micronutrients for plants andor animals, and the modelling of critical loads of heavy metals for use in. Heavy metals in agricultural soils of the european union. Index terms heavy metal pollution, resistant strain, carbon microspheres. Resources of nigeria, dpr 14 for maximum allowable concentration of heavy metals in soil table 1. Pollution assessment of heavy metals in soils of india and. Pdf heavy metal pollution of soil around solid waste. Heavy metal and metalloid pollution of soil, water and. Following a description of the various sources and factors influencing the contents of heavy metal pollution in postcatastrophic and agricultural soils, subsequent chapters examine soil enzymes and eggs as biomonitors, lead adsorption, the effects of arsenic on microbial diversity, and the effects of mediterranean grasslands on abandoned mines. In this study, 101 pairs of soil and rice samples were collected from the major riceproducing areas along the yangtze river in china. Biochemical, biotoxic, environment, heavy metals, pollution. Pollution of the surface soils by the heavy metals was classified into five levels based on the corresponding pi n values table s2. After investigating the options presented by the various approaches and thresholds applied by them, we chose the standards set in the finnish.
This study investigates the heavy metal contents in soils and plants at awotan and ajakanga dumpsites in ibadan with a particular reference to physiochemical and heavy metal levels of the underlying soils, the relationship between the dumpsite soil. Remediation of heavy metal pollution in soil by microbial. Heavy metals refer to some metals and metalloids possessing biological toxicity, such as cadmium, mercury, arsenic, lead, and chromium. Analysis of soil heavy metal pollution and pattern in. Moreover, heavy metals enter food chains from polluted soil, water and air, and consequently cause food contamination, thus posing a threat to human and animal health. Introduction the term heavy metals refers to any metallic element that has a relatively high density and is toxic or poisonous even at low concentration lenntech, 2004. Soil contamination of areas covered by industrial plants and farms is one of the major. Moreover, heavy metals enter food chains from polluted soil, water and air, and consequently cause food contamination, thus posing a threat to human and animal. Starting from the agricultural soil in our food basket these heavy metals and metalloids, like cr, mn, co, ni, cu, zn, cd, sn, hg,pb and others, showing significant toxic impacts.
This has compromised the ability of the environment to foster life and render its intrinsic values. Heavy metal pollution can arise from many sources but most commonly arises from the purification of metals, e. Smelting and burning of coal, oil and waste will bring heavy metal pollution into the atmosphere. Therefore, the purposes of this study were 1 to determine the concentration and distribution of heavy metals cd, cr, cu, zn, pb and ni in soil from steel industrial districts, 2 to identify the potential source of heavy metals by multivariate analysis, and 3 to assess the pollution level, potential ecological risk and human health risk. Relationship between heavy metal concentrations in soils. Heavy metals exhibit toxic effects towards soil biota by affecting k ey. The sever change and degradation in air, soil and water due to environmental pollution 16. Soils polluted with heavy metals have become common across the globe due to increase in geologic and anthropogenic activities. In addition, the standard employed for interpreting soil heavy contamination pollution cp varies from country to country based on chosen factors 15 actual measurement of metal concentration in soil c p value target values from reference. Heavy metals are toxic to soil, plants, aquatic life and human health if their concentration is high.
The environment and its compartments have been severely polluted by heavy metals. Pdf environmental pollution, especially by chemicals, is one of the most important factors in the destruction of biosphere components. Heavy metal pollution in soil or rice grains is of increasing concern. Lead poses human health hazards when particles are inhaled. Sources of heavy metal pollution in agricultural soils of. Heavy metal contamination of soil may pose risks and hazards to humans and. Heavy metal pollution is covert, persistent and irreversible 8.
Following the modernday urbanization and industrialization, heavy metal contamination has become a prime concern for todays society. Excessive accumulation of heavy metals is not only toxic to animals and plants 1, 2, but can also lead to elevated heavy metal intake in humans through the food chain. Exposure to heavy metals as a result of consumption of contaminated vegetables, as well as their toxicity, is a serious problem. Municipal and industrial sewage also is an important source of those. The intensification of agricultural landuse and changes in farming practices. Pdf effects of heavy metals on soil, plants, human. To evaluate the magnitude of contaminants in the soil profile and intensity of heavy metal pollution at the different depths of soil, geoaccumulation index igeo was computed according to the abundance of species in source material found in the earths crust and the. Metals from air pollution accumulate in the top 12 inches of soil and tend to stay put. Although soil heavy metal pollution is often mentioned recently, little information is available on heavy metal transfer from soil to vegetable 3, 19. Heavy metal pollution in soils is a growing risk that is of great concern due to the potential negative impacts of heavy metals on human health and the environment yanez et al. The sources of various heavy metals are listed in table table1. Results revealed that metals levels were generally high in mineralized and urban soils and lower in agricultural soils whilst forest soils were lease by anthropogenic pollution.
Environmental contamination by heavy metals intechopen. Heavy metals and metalloids in groundwater and surface water are closely related to human healthand have been extensively studied. Heavy metals contamination and what are the impacts on. Phytoremediation of heavy metal polluted soils and water. The single pollution index in soil spi and nemerow composite pollution index ncpi were used to assess the degree of hm pollution in soil, and the crop pollution index cpi was used to explore the degree of hm accumulation in crops. The presence of any metal may vary from site to site, depending upon the source of individual pollutant. This study is an attempt to assess the extent of toxic metals, including fe, cu, zn, mn, pb, cd and ni in surface water, groundwater, river sediment and crop field soil samples collected from simlong coalfield area in sahebganj district of jharkhand. Heavy metal and metalloid pollution of farmland and crops can substantially impact food safety as well as human health 20.996 589 721 1173 1458 641 989 644 1360 575 765 616 200 661 1505 1480 77 1366 1299 1549 68 239 275 1251 242 581 799 1494 707 996 612 779