Buildup Of Heavy Metals Research Articles

Role of Solids in Heavy Metals Buildup on Urban Road Surfaces

AbstractSolids are widely identified as a carrier of harmful pollutants in stormwater runoff exerting a significant risk to receiving waters. This paper outlines the findings of an in-depth investigation on heavy metal adsorption to solids surfaces. Pollutant build-up samples collected from 16 road sites in residential, industrial, and commercial land uses were separated into four particle size ranges and analyzed for a range of physicochemical parameters and nine heavy metals including Iron (Fe), Aluminum (Al), Lead (Pb), Zinc (Zn), Cadmium (Cd), Chromium (Cr), Manganese (Mn), Nickel (Ni), and Copper (Cu). High specific surface area (SSA) and total organic carbon (TOC) content in finer particle size ranges were noted, thus confirming strong correlations with heavy metals. On the basis of their physicochemical characteristics, two different types of solids originating from traffic and soil sources were identified. Solids generated by traffic were associated with high loads of heavy metals, such as Cd and ...

Heavy Metals in Brown Rice ( Oryza sativa L.) and Soil After Long-Term Irrigation of Wastewater Discharged from Domestic Sewage Treatment Plants

A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals (Pb, Cd, Cu, and Zn) into brown rice ( Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time (3 years). The range of Pb, Cd, Cu, and Zn was 5.10 ± 0.01, 0.105 ± 0.017, 5.76 ± 0.42, and 23.56 ± 1.40 mg kg −1, respectively in the domestic wastewater-irrigated soil, and 0.370 ± 0.006, 0.011 ± 0.001, 0.340 ± 0.04, and 2.05 ± 0.18 mg kg −1, respectively, in the domestic wastewater-irrigated brown rice. The results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb, Cd, Cu, and Zn in soil and brown rice ( P < 0.01). The concentrations of heavy metals in brown rice were lower than the recommended tolerable levels proposed by the Joint FAO/WHO Expert Committee on Food Additives. However, the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.

Analysis of build-up of heavy metals and volatile organics on urban roads in gold coast, Australia

Urban water quality can be significantly impaired by the build-up of pollutants such as heavy metals and volatile organics on urban road surfaces due to vehicular traffic. Any control strategy for the mitigation of traffic related build-up of heavy metals and volatile organic pollutants should be based on the knowledge of their build-up processes. In the study discussed in this paper, the outcomes of a detailed experimental investigation into build-up processes of heavy metals and volatile organics are presented. It was found that traffic parameters such as average daily traffic, volume over capacity ratio and surface texture depth had similar strong correlations with the build-up of heavy metals and volatile organics. Multicriteria decision analyses revealed that that the 1-74 microm particulate fraction of total suspended solids (TSS) could be regarded as a surrogate indicator for particulate heavy metals in build-up and this same fraction of total organic carbon could be regarded as a surrogate indicator for particulate volatile organics build-up. In terms of pollutants affinity, TSS was found to be the predominant parameter for particulate heavy metals build-up and total dissolved solids was found to be the predominant parameter for the potential dissolved particulate fraction in heavy metals buildup. It was also found that land use did not play a significant role in the build-up of traffic generated heavy metals and volatile organics.

Impacts of Traffic and Rainfall Characteristics on Heavy Metals Build-up and Wash-off from Urban Roads

An investigation into the effects of changes in urban traffic characteristics due to rapid urbanisation and the predicted changes in rainfall characteristics due to climate change on the build-up and wash-off of heavy metals was carried out in Gold Coast, Australia. The study sites encompassed three different urban land uses. Nine heavy metals commonly associated with traffic emissions were selected. The results were interpreted using multivariate data analysis and decision making tools, such as principal component analysis (PCA), fuzzy clustering (FC), PROMETHEE, and GAIA. Initial analyses established high, low, and moderate traffic scenarios as well as low, low to moderate, moderate, high, and extreme rainfall scenarios for build-up and wash-off investigations. GAIA analyses established that moderate to high traffic scenarios could affect the build-up, while moderate to high rainfall scenarios could affect the wash-off of heavy metals under changed conditions. However, in wash-off, metal concentrations in 1-75 μm fraction were found to be independent of the changes to rainfall characteristics. In build-up, high traffic activities in commercial and industrial areas influenced the accumulation of heavy metal concentrations in particulate size range from 75 - >300 μm, whereas metal concentrations in finer size range of <1-75 μm were not affected. As practical implications, solids <1 μm and organic matter from 1 - >300 μm can be targeted for removal of Ni, Cu, Pb, Cd, Cr, and Zn from build-up, while organic matter from <1 - >300 μm can be targeted for removal of Cd, Cr, Pb, and Ni from wash-off. Cu and Zn need to be removed as free ions from most fractions in wash-off.

Health risks of heavy metals in sewage‐irrigated soils and edible seeds in Langfang of Hebei province, China

Human exposure to heavy metals is attributed to consumption of food crops grown in polluted soil environment. The objective of our study was to assess the health risks of heavy metals in edible seeds of crops grown in sewage-irrigated soils located in the Langfang of Hebei province, China. Here, heavy metal contents in soils and plants were determined using an internal standard and high-resolution inductively coupled plasma mass spectrometry. There was a relative buildup of heavy metals in sewage-irrigated soils in the study area; in particular, all Cr and partial Zn and Cu showed higher concentrations than the limits proposed by the World Health Organization, European Union (EU) and UK. Heavy metal concentrations in edible seeds of plants grown in sewage-irrigated soils partly exceeded the permissible limits set by the EU, UK and the State Environmental Protection Administration in China. With the exception of Cu, health risk index values of each heavy metal investigated by intake of the edible seeds were less than 1. Here, a health risk index of < 1 is considered safe for human consumption. The study indicated that there was a relative absence of health risks associated with the ingestion of sewage-irrigated edible seeds.

Clinical evidence supporting the use of an activated clinoptilolite suspension as an agent to increase urinary excretion of toxic heavy metals

Clinical evidence supporting the use of an activated clinoptilolite suspension as an agent to increase urinary excretion of toxic heavy metals James L Flowers1, Stewart A Lonkey2, Erik J Deitsch31Eno Research and Development, Inc., Hillsborough, NC, USA; 2University of California at Los Angeles, Los Angeles, CA, USA; 3Wellness Industries, LLC, Parkland, FL USAAbstract: Effective treatment of chronic illness resulting from the long-term buildup of heavy metals in the body, such as chelation therapy, presents numerous clinical challenges, including undesirable side effects and unpredictable efficacy. Use of a naturally occurring zeolite, clinoptilolite, to remove these toxic substances may offer an efficacious and safe alternative to the traditional approaches. This study was designed to evaluate the ability of activated clinoptilolite suspended in water (ACS) to remove heavy metals from the body through urinary excretion without the undesirable removal of physiologically important electrolytes. The protocol utilized two treatment groups, each consisting of eleven healthy men aged 36 to 70 years. Volunteers were given a commercially available version of the study substance for seven days (Group 1) and 30 days (Group 2) and urine samples were collected at specified time points in the study. Changes in urinary concentration of the heavy metals were measured by inductively coupled plasma mass spectrometry and compared to the baseline. Also, serum samples were obtained from five individuals in each group and serum electrolytes were measured prior to and after taking the product. Participants in both groups had increased concentrations of heavy metals in the urine with the peak excretion at around day 4. No clinically significant alterations in serum electrolyte levels were seen at either seven or 30 days on ACS. In conclusion, this study demonstrates that the daily use of an activated clinoptilolite suspension represents a potentially safe and effective way to remove toxic heavy metals from the body through increased urinary excretion without removing clinically detrimental amounts of vital electrolytes.Keywords: zeolite, clinoptilolite, heavy metals, toxins, atomic absorption spectroscopy

Chemical Changes and Heavy Metal Partitioning in an Oxisol Cultivated with Maize (Zea mays, L.) after 5 Years Disposal of a Domestic and an Industrial Sewage Sludge

The need for solutions to minimize the negative environmental impacts of anthropogenic activities Fhas increased. Sewage sludge is composed of predominantly organic matter and can be used to improve soil characteristics, such as fertility. Therefore, its application in agriculture is an adequate alternative for its final disposal. However, there is a lack of information on its long-term effects on soil changes in tropical areas. Thus, the objectives of this study were to determine (i) the effect of sewage sludge application on heavy metal build-up in soil and maize grains and leaves, and (ii) the effects of soil amendment with sewage sludge on the chemical properties of a Brazilian oxisol. Besides the increasing levels of Zn, Cu, Ni, and Cr, amending soil with sewage sludge also alters the distribution of these metals by increasing the mobile Phases, which correlated significantly with the increase in metal extraction with two single extractants, Mehlich 1 and DTPA (Diethylene triamine pentaacetic acid). The levels of Fe, Mn, Zn, and Cu in maize grains and leaves increased with the type and rate of sewage sludge application. Nevertheless, metal build-up in soil and plants was within the allowed limits. Significant differences were also found in soil characteristics like humic fractionation with the applied sewage doses. The data obtained does not indicate any expressive drawbacks in the use of sewage sludge as a soil amendment, as the heavy metal concentrations observed are unlikely to cause any environmental or health problems, even overestimated loadings, and are in accordance with the Brazilian regulations on farming land biosolid disposal.

Study of Heavy Metal Distribution in Soils Impacted with Crude Oil in Southern Nigeria

The study presents the levels and enrichment factors of heavy metals in soils of southern Nigeria that have received significant impact of crude oil spillage. The results revealed that the concentrations of heavy metals in the examined soils fitted into levels found in agricultural soils except for cadmium. Heavily impacted sites showed elevated levels of heavy metals compared to less impacted sites and background levels. The mean enrichment factors for Cd, Cu, Cr, Pb, Mn, Ni, and Zn were 37.3, 2.8, 14.4, 14.0, 0.77, 5.4, and 1.27 for topsoil and 37.5, 1.30, 7.81, 1.59, 4.12, and 1.28 for subsoil, respectively. This clearly indicates that there is gradual build-up of heavy metals in these soils as a result of the oil spillage and related anthropogenic activities in this area.

Heavy metal accumulation in vegetables irrigated with water from different sources

The present study was carried out to assess levels of different heavy metals like iron, manganese, copper and zinc, in vegetables irrigated with water from different sources. The results indicated a substantial build-up of heavy metals in vegetables irrigated with wastewater. The range of various metals in wastewater-irrigated plants was 116–378, 12–69, 5.2–16.8 and 22–46 mg/kg for iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn), respectively. The highest mean levels of Fe and Mn were detected in mint and spinach, whereas the levels of Cu and Zn were highest in carrot. The present study highlights that both adults and children consuming vegetables grown in wastewater-irrigated soils ingest significant amount of these metals. However, the values of these metals were below the recommended maximum tolerable levels proposed by the [Joint FAO/WHO Expert Committee on Food Additives (1999). Summary and conclusions. In 53rd Meeting, Rome, June 1–10, 1999]. However, the regular monitoring of levels of these metals from effluents and sewage, in vegetables and in other food materials is essential to prevent excessive build-up of these metals in the food chain.

Demonstration of Sustainable Crop Growth Using Production Water Treated with Solar Membrane Distillation Technology: A Case Study

ABSTRACT This paper summarizes the establishment of a demonstration pilot farm at a dessert environment for sustainable crop growth using reed-bed-outlet production water that was treated with solar membrane distillation (i.e., Solar Dew) technology. Specifically, land preparation, plot layout, and the design and installation of an irrigation system were described. Plant tissue analysis indicated that there was no build-up of heavy metals. Analysis of soil over the test period showed that there was a slight build-up of salts. This was attributed to the use of sewage treatment plant water prior to irrigation with Solar Dew water. The salt content of the treated water varied from low (i.e., 11 mg/L) to acceptable (i.e., 122 mg/L). Due to the lower than expected fresh water production capacity of the solar membrane distillation system (i.e., 4 L/m2d vs. 5 L/m2d), the field testing of crops was limited to date palm and citrus trees. Some problems were encountered with the novel desalination system. Recommendations were included in the paper. Overall, it was successfully demonstrated that sustainable crop growth could be achieved using reed-bed-outlet production water that had been treated with Solar Dew membrane technology.

Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China

Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher ( P ≤ 0.001) than in plants grown in the reference soil, and exceeded the permissible limits set by the State Environmental Protection Administration (SEPA) in China and the World Health Organization (WHO). Furthermore, this study highlights that both adults and children consuming food crops grown in wastewater-irrigated soils ingest significant amount of the metals studied. However, health risk index values of less than 1 indicate a relative absence of health risks associated with the ingestion of contaminated vegetables.

On Iron Enrichment, Star Formation, and Type Ia Supernovae in Galaxy Clusters

The nature of star formation and Type Ia supernovae (SNIa) in galaxies in the field and in rich galaxy clusters are contrasted by juxtaposing the build-up of heavy metals in the universe inferred from observed star formation and supernovae rate histories with data on the evolution of Fe abundances in the intracluster medium (ICM). Models for the chemical evolution of Fe in these environments are constructed, subject to observational constraints, for this purpose. While models with a mean delay for SNIa of 3 Gyr and standard initial mass function (IMF) are consistent with observations in the field, cluster Fe enrichment immediately tracks a rapid, top-heavy phase of star formation -- although transport of Fe into the ICM may be more prolonged and star formation likely continues to redshifts 3 times more efficient in rich clusters than in the field, mitigating the overcooling problem in numerical cluster simulations. Both the fraction of baryons cycled through stars, and the fraction of the total present-day stellar mass in the form of stellar remnants, are substantially greater in clusters than in the field.

Heavy metal accumulation in calcareous soil and sorghum plants after addition of sulphur-containing waste as a soil amendment in Turkey

The purpose of this work was to evaluate the effect of sulphur containing industrial waste with respect to heavy metals on calcareous clay soil and sorghum (Sorghum bicolor L.) plant, as soil amendment. Pot experiment was established with a rate of 0, 20, 40, 60 t ha−1 air dry waste and 0.5, 1.0, 1.5 t ha−1 elemental sulphur and 0.5 t ha−1 sulphur + 20 t ha−1 waste. The use of waste on the soil with high CaCO3 and clay content did not create heavy metal (Ni, Cr, Co and Cd) build-up or toxicity. Even after the application of the high level of waste, it could not be seen any important toxic element accumulation in sorghum plant. Although the sulphur-rich waste, approximately up to 1 million t in the vicinity of Keçiborlu Sulphur Factory Isparta/Turkey, can be considered as amendment product for reclamation of saline-sodic and calcareous soils common in Turkey and other countries, repeated waste applications would result in different heavy metal accumulation rates. Therefore, it is needed to be examined with long term field experiments and different crops.

Sources and timing of anthropogenic pollution in the Ensenada de San Simón (inner Ría de Vigo), Galicia, NW Spain: an application of mixture-modelling and nonlinear optimization to recent sedimentation

The Ensenada de San Simón is the inner part of the Ría de Vigo, one of the major mesotidal rías of the Galician coast, NW Spain. The geochemistry of its bottom sediments can be accounted for in terms of both natural and anthropogenic sources. Mixture-modelling enables much of the Cr, Ni, V, Cu, Pb and Zn concentrations of the bottom and subaqueous sediments to be explained by sediment input from the river systems and faecal matter from manmade mussel rafts. The compositions and relative contributions of additional, unknown, sources of anomalous heavy-metal concentrations are quantified using constrained nonlinear optimization. The pattern of metal enrichment is attributed to: material carried in solution and suspension in marine water entering the Ensenada from the polluted industrial areas of the adjacent Ría de Vigo; wind-borne urban dusts and/or vehicular emissions from the surrounding network of roads and a motorway road-bridge over the Estrecho de Rande; industrial and agricultural pollution from the R. Redondela; and waste from a former ceramics factory near the mouth of the combined R. Oitabén and R. Verdugo. Using 137Cs dating, it is suggested that heavy metal build-up in the sediments since the late 1970s followed development of inshore fisheries and introduction of the mussel rafts (ca. 1960) and increasing industrialisation.

Growth conditions, elemental accumulation and induced physiological changes in Chinese cabbage

Soils contaminated with low levels of heavy metals and other trace elements are now frequently used for vegetable growing. In this situation, heavy metals and trace elements from these polluted soils may accumulate in the agricultural plants being grown in them and thereby enter the human food chain. The objectives of this study are to elucidate the effects of growth conditions, manipulated by the crop covers, on the phytoaccumulation of elements, and to investigate the conceivable influences of these conditions on the plant biochemistry. In three consecutive years of field experiments, open air (T 0), and floating rowcover treatments (T 1: perforated polyethylene 50 μm; T 2: polypropylene 17 g m −2) were used to produce different environmental conditions for the growth of Chinese cabbage [ Brassica rapa L. (Pekinensis group) cv. ‘Nagaoka 50’]. Five samplings (whole tops) were carried out from transplanting to harvest and measurements of B, Al, Ag, Si and Ca concentration as well as phenolics (orto-diphenols, total phenols and anthocyanins), pectic fractions, amino acids (histidine, phenylalanine and tyrosine) and polyphenol oxidase activity, were carried out in samples. The T 1 (perforated polyethylene sheet) gave greater B, Al, Ag and Si concentration and phytoextraction (in weight units) than the open-air control. These findings can help to develop new cost-effective techniques for phytoremediation as the application of plastic covers in the field. The build-up of heavy metals in those crops would make the product less suitable for human consumption.

Stormwater Contamination of Urban Estuaries. 2. Testing a Predictive Model of the Build-Up of Heavy Metals in Sediments

We describe the results of a sampling program to test a simple, management-oriented, predictive model of the build-up of contaminants (Cu, Pb, and Zn) in sediments in sheltered estuaries. The model, described in detail in a companion paper, is generally applicable to these environments but its development and testing is described for two urban estuaries in Auckland, New Zealand. There was good agreement between observed concentrations of metals and those predicted by the model. The model predicted larger concentrations within a defined settling zone at the upper end of the estuary than outside this zone, and such a difference was detected for lead and zinc. Differences in concentrations of metals were detected among locations several hundreds of meters apart, with increasing concentrations from downstream to upstream locations. These patterns were apparent above smaller scale variation among and within sites 10s of meters apart within each location. This small-scale variation did not conform to any obvious patterns. For example, there were no clear patterns in the metals distributions in sediments among different shore heights. Patterns of contaminants distributions found in the present study may be generalized to similar urban estuaries in other parts of the world through their correspondence to those derived from the model, which is based on general assumptions and principles.

Stormwater Contamination of Urban Estuaries. 1. Predicting the Build-Up of Heavy Metals in Sediments

Many coastal cities are situated around estuaries, which act as traps for urban-derived contamination. To investigate urban development options, to help manage the urbanization process, and to set priorities for retrofitting urban stormwater controls, a model was developed to predict the build-up of contaminants (Pb, Zn, and Cu) in the sediments of sheltered estuaries. This model broadly integrates processes occurring in the estuary and predicts the distribution of sediment-associated contaminants throughout the estuary. It is based on yields of suspended sediment and contaminants from developing and mature catchments and is applicable to shallow, sheltered estuaries and harbors that have accumulated fine sediments. The information required to develop and run the model, and the sensitivity of the model to variation in its parameters, is described in detail.

Discussion: Effect of pH on metal solubilization from sewage sludge: a neural-net-based approach

Detoxification of sludge from municipal wastewater treatment plants has recently gained great importance in many cities in Europe and North America (Becker et al. 1990). The reasons are mainly to resolve the sludge disposal problem and increase the use of sludges as a soil amendment. Disposal sf sewage sludge has become a major problem because ocean disposal is banned almost everywhere; incineration and landfill face problems of cost and public acceptance. Removal of toxic chemicals, particularly heavy metals (e. g . , Zn, Cd, Cr, Ni, Cu, and Pb), from sewage sludges will, therefore, enhance its agricultural use and increase its value as fertilizer, and decrease the need for disposal. In one study where maerobically composted sewage sludge was used as soil conditioner and organic fertilizer, more vigorous crop establishment and higher yields were obtained (Bevacqua and Mellano 1993). The cumulative effect of multiple application of sludge over a 2-year period was clearly evident at the time of harvest. The use of sludge had positive effects in regulating soil pH, increasing the levels of the primary plant nutrients (e.g., nitrogen, phosphorus, and potassium) and water holding capacity of the soil. It also had the negative effects of increasing soluble salts such as Ca, Mg, Na, C1, and heavy metals. Accumulation of heavy metals in the soil poses the major concern in the use of sewage sludge on agricultural soils; these metals can build up with repeated applications. As metal concentrations increase, metal toxicity can suppress plant growth and metals can pass into the food chain. It was also demonstrated by the same team that, when the sludge contains low concentrations of heavy metals, the resulting buildup of heavy metals in the soil was small and was far below the amounts suggested for agricultural soils. Chenaical characteristics and suggested levels of heavy metals are shown in Table 1 (Bevacqua and Mellano 1993). It is a cost-effective approach to predict solubilization of metals from sewage sludge before treating the sludge for

SEWAGE SLUDGE COMPOST AS A SOIL AMENDMENT FOR HORTICULTURAL CROPS

Municipal sewage sludge, previously amended with Eucalyptus tree trimmings and composted, was incorporated to a depth of 30 cm at rates of 0, 12.3 and 24.6 dry MT/ha for a field planting of onion, snapdragon, turf and spinach. In a similar subsequent planting, the sludge compost was incorpoated to a depth of 10 cm. Additional treatments address the residual effect of the material. The results indicated sludge compost incorporated to a depth of 30 cm had no effect on crop yields, but when incorporated to a depth of 10 cm there was a significant increase in yields for all test crops. No buildup of heavy metals, soluble salts or changes in soil pH that would depress crop growth were detected. Two greenhouse experiments employed equivalent rates and the same four crops. Two materials, sludge compost and heat-dried sludge were compared. The former contained composted Eucalyptus tree trimmings. The latter did not. The results showed both materials were equally beneficial to crop growth and the presence of Eucalyptus trimmings did not decrease yields

Evolutionary economics and environmental imperatives

The long-range biological imperative for survival has its economic counterpart. The present techno-economic system, with its heavy dependence on exhaustible stocks of natural resources, including environmental waste assimilative capacity, is unsustainable. The stocks of high quality raw materials, such as fuels and metal ores, are being drawn down rapidly. But this is the least of the problems because of possible technical ‘fixes’. More ominous, there is an irreversible disappearance of tropical rainforests and other valuable and irreplaceable ecosystems, erosion of topsoil, a buildup of toxic heavy metals in soils and sediments, an accumulation of ‘greenhouse gases’ in the atmosphere, and a catastrophic loss of biological diversity. None of these trends is reversible by any known or plausible technological intervention. Long-run human survival therefore requires that the use of the environment as a ‘sink’ for waste residuals, especially from fossil fuel combustion and dissipative uses of heavy metals, must be slowed down drastically in the near future. The paper examines the relevant economic adjustment mechanisms in terms of both ‘standard’ neo-classical and evolutionary theories. It concludes that a policy based on reliance on market signals (i.e. prices) alone to induce change is likely to be ineffective. Even if the polluter pays principle (PPP) were fully implemented, market mechanisms would not suffice. The problem is that existing large-scale systems evolved during a period when environmental concerns were not serious, and now retain their economic dominance partly due to economies of scale and partly through influence over the political system.