Terms Of Heavy Metal Pollution Research Articles

Heavy Metal Contamination and Potential Ecological Risk Assessment in Sediments of Lake Bafa (Turkey)

This study examined the spatio-temporality of heavy metal concentrations (Al, Cd, Co, Cr, Fe, Mn, Ni, Pb and Zn) in the sediments of Lake Bafa, one of the most important wetlands of Turkey’s Aegean region. The study evaluated sediment quality according to threshold effect concentration (TEC) and probable effect concentration (PEC) values based on sediment quality guidelines (SQG), and provided a potential ecological risk assessment (PERI) along with indices such as geoaccumulation index (NIgeo), enrichment factor (EF), contamination factor (CF), and pollution load index (PLI). For this purpose, surface sediment from 10 different points and core samples from three different points were seasonally collected and the concentrations of nine heavy metals were determined by ICP-MS. The findings indicated the following accumulation order of heavy metals in the sediment: Fe > Al > Mn > Ni > Cr > Zn > Pb > Co > Cd, with concentrations of Al, Mn, and Ni being high in the surface sediment samples. According to the NIgeo, surface sediment and core samples were very slightly polluted with Cr, Mn, and Co at most stations, while five stations were slightly polluted with Cd. Regarding EF, the lake was at risk in terms of Al and Pb accumulation. The CF results indicated that the lake was under pressure in terms of heavy metal pollution. The PLI results indicated a significant pollution hazard at all stations, while the PERI analysis indicated moderate risk of heavy metal pollution at some stations. As one of the most comprehensive studies applying such indices to Lake Bafa, the results are very significant in terms of evaluating the lake’s ecological sustainability.

Initial Studies on the Effect of the Rice-Duck-Crayfish Ecological Co-Culture System on Physical, Chemical, and Microbiological Properties of Soils: A Field Case Study in Chaohu Lake Basin, Southeast China.

Rice-duck and rice-crayfish co-culture patterns can increase soil productivity and sustainability and reduce the use of chemical pesticides and fertilizers, thereby reducing the resulting negative environmental impacts. However, most studies have focused on the rice-duck and rice-crayfish binary patterns and have ignored integrated systems (three or more), which may have unexpected synergistic effects. To test these effects, a paddy field experiment was carried out in the Chaohu Lake Basin, Hefei city, Southeast China. Four groups, including a rice-duck-crayfish ecological co-culture system (RDC), idle field (CK), single-season rice planting system (SSR), and double-season rice planting system (DSR), were established in this study. The results showed that the RDC improved the soil physical properties, fertility, humus content, and enzyme activity. In the RDC system, the soil total nitrogen content ranged from 8.54% to 28.37% higher than other systems in the 0-10 cm soil layer. Similar increases were found for soil total phosphorus (8.22-30.53%), available nitrogen (6.93-22.72%), organic matter (18.24-41.54%), urease activity (16.67-71.51%), and acid phosphatase activity (23.41-66.20%). Relative to the SSR treatment, the RDC treatment reduced the total losses of nitrogen and phosphorus runoff by 24.30% and 10.29%, respectively. The RDC also did not cause any harm to the soil in terms of heavy metal pollution. Furthermore, the RDC improved the yield and quality of rice, farmer incomes, and eco-environmental profits. In general, the RDC can serve as a valuable method for the management of agricultural nonpoint-source pollution in the Chaohu Lake area and the revitalization of the countryside.

Comprehensive assessment of pollution indices, sources apportionment and ecological risk mapping of heavy metals in agricultural soils of Raebareli District, Uttar Pradesh, India, employing a GIS approach

AbstractIn the environment, heavy metal contamination is a well known problem due to its persistence and toxicity. Heavy metal pollution has significantly affected soil properties and functions, resulting in significantly increased land degradation as a result of anthropogenic interventions that include mining and various industrial and agriculture activities. While heavy metals pollution in soil have been studied very rarely in this District, this paper explores the current status of agricultural soil pollution by heavy metals in Raebareli. This study identifies heavy metals as well as their quantities in the soil and their spatial distribution; our study employed various pollutant indices and geographical information system (GIS) techniques. This research work evaluated the physiochemical properties, the pollution load index (PLI), contamination factor (CF) and the degree of contamination and geoaccumulation (Igeo) in sodic soils of the Raebareli District, Uttar Pradesh, India. Uchahaar site (US) has the most polluted soil, while the Bacharawa site (BS) has the least contaminated soil. The soil quality has degraded due to anthropogenic interventions at most sites. There is slight to moderate contamination by heavy metals at all sites. The Igeo values in subSites US1, US2 and US3 included high levels of Cu, Zn, Pb, Mn and Sr. SubSites BS2 and BS3 have high Sr levels and US1 has a high As level all these Subsites have high anthropogenic influences. The PLI values indicate that most of the study subSites come under a slightly polluted class, except US1 where the PLl was > 3 indicating severe heavy metal pollution at this site. All the pollution indices have then been utilized for building maps using the IDW method of interpolation. The spatial projection of PLI and ecological risk index (Er) values suggest that the northern part of Raebareli has a high pollution load and ecological risk in terms of heavy metal pollution. This study provide valuable information that policymakers could use to develop an appropriate plan to control pollution within the agricultural sector.

Pilot groundwater radon mapping and the assessment of health risk from heavy metals in drinking water of southwest, Nigeria

Radon and heavy metals are sources of groundwater pollution and are identified as potential carcinogens. Southwest Nigeria's populace mostly relies on groundwater source for drinking. This study aims to map radon distribution in groundwater of southwest Nigeria and to determine the health risk of radon and heavy metal in drinking water. Radon concentrations of 145 groundwater samples were measured using RAD7 electronic radon detector and heavy metal concentrations of 52 groundwater samples were measured using atomic absorption spectrophotometer. Radon concentration distributions were delineated using geographical information system. Radon concentration of water samples ranges between 1.6 Bq l−1 and 271 Bq l−1 with an average value of 35.9 ± 38.4 Bq l−1. The average groundwater radon concentration is higher than US-EPA recommended level of 11.1 Bq l−1 but lower than the WHO recommended limit of 100 Bq l−1. The estimated average annual effective radiation doses to infants, children, and adults are 29 μSvy−1, 41 μSvy−1 and 92 μSvy−1 respectively. The radon distribution map of the study area reveals regions of high, medium, and low groundwater radon concentrations. The average concentration values of heavy metals in groundwater samples are of the order Mn > Zn > Pb > Cu > Cr > Ni > Cd. 84% of groundwater exhibits good to excellent quality in terms of heavy metal pollution. However, about 16% of the samples which lie in the sedimentary regions of Ogun and Lagos States exhibit poor to very poor quality. Overall, ingestion of groundwater in the study area may not pose a serious health hazards from radon ingestion and heavy metal toxicity.

Trend analysis of heavy metals, Ni, Pb, Cd and As in marine sediments – A case study of ONGC Block (KG OSN 2009/2) in Krishna-Godavari Basin, Bay of Bengal

Heavy metals can be termed as conservative pollutants, introduce into the aquatic systems as a result of the weathering of soils and rocks, from under water volcanic eruption and other anthropogenic activities. Thereby it changes the natural concentration of metals in seawater resulting in a ten or even hundred fold increase near the source of an effluent discharge. While some metals like manganese (Mn), copper (Cu), iron (Fe) and zinc (Zn) are biologically important for marine life, others like Nickel (Ni), Lead (Pb), Cadmium (Cd), and Arsenic (As) are non-essential and become toxic at higher concentrations. Associated to particulate matters, heavy metals tends to stay in solution for a very long time, but they will end up in the sediments, Therefore concentrations in the sediments are often higher than those in solution. In the sediments, these particles may form an important secondary source of contamination, even after the primary source has disappeared. Therefore, there is a need for timescale monitoring of the levels of these metals in all the marine resources, so as to establish the trends that could be linked to anthropogenic activities. In this paper, the effect of E&P activities of ONGC Block (KG OSN 2009/2) in Krishna-Godavari Basin, Bay of Bengal is studied, by carrying out a trend analysis of heavy metal concentration (60Ni, 208Pb, 111Cd, and 75As) in the sediments from this block. Sediments samples were collected from the ONGC Block (KG OSN 2009/2) using OSPAR commission guidelines and the heavy metal concentration values averaged out. These average values are used to analyze the trend for a period extending from 2015 up to 2019. In the years 2016, the pollution level recorded was minimum. Overall, from 2015 to 2019, 208Pb shows a decreasing trend line, but 60Ni, 111Cd, and 75As shows an increasing trend line. Albeit the increasing trend of 60Ni, 111Cd, and 75As concentration are a matter of concern, but all the values are below the ERL (effects range low) set by the National Oceanographic and Atmospheric Administration (NOAA), USA. Hence, it can be concluded that the oil field activity of ONGC in the Eastern Offshore has not made any significant impact on the marine environment, in terms of heavy metal pollution. A statistical analysis in terms of Relative Contamination Factors and Pollution Load Index has also been done in the paper.

Assessment of the effects of municipal landfills on the metal pollution in the surrounding soils: A case study in Iraq

The present investigation has been devoted to assessing the environmental impacts of a local landfill, in the north of Hilla city, Iraq, on the surrounding soils in terms of heavy metal pollution. The concentrations of heavy metals, namely chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb) were measured during, November 2019, at three investigation sites that located at distances of 10 (site 1), 20 (site 2) and 30 m (site 3) from the edge of the mentioned landfill. Soil samples were collected from these sites at a constant depth of 20 cm. The collected samples were air-dried, manually crushed, and sieved through a 2 mm mesh before subjecting them to a chemical digesting process. The concentrations of the targeted metals were measured using an inductively coupled plasma optical emission spectrometry and compared to the standards of the State Environmental Protection Administration (SEPA). The obtained results showed that the highest concentrations of the targeted metals were in site 1, while the lowest concentrations were detected at site 3. Generally, it was found that the concentrations of the studied metals followed the order: Cr>Pb>Ni>Cu. Additionally, it was noticed that all the measured concentrations were within the limitations of the SEPA.

Continental-scale spatial distribution, sources, and health risks of heavy metals in seafood: challenge for the water-food-energy nexus sustainability in coastal regions?

Rare information on the seafood safety and the coastal water-food-energy nexus sustainability in terms of seafood safety is available. This study investigated the distribution of heavy metals in 3 kinds of seafood (bivalve molluscs, fish, and crustaceans) collected from coastal areas along the 18,000 km coastline of China. Risk assessment and source apportionment of heavy metals, and the coastal water-food-energy nexus sustainability in terms of heavy metal pollution were also performed. The results showed that total concentrations of 8 heavy metals (Cu, Pb, Zn, Cd, Cr, Hg, As, and Ni) in seafood varied with sampling sites and species by following the order of bivalve molluscs > crustaceans > fish. Estimated daily intake (EDI) analysis indicated that it was safe for humans to consume seafood in all sampling sites. Non-cancer risks posed by heavy metals were acceptable for 99.1% of adult and 97.7% of children. However, Cr and As in 72% of fish samples caused high cancer risks for children. The farmed fish posed relatively low risk in comparison with the wild fish suggested that it might be safer to consume farmed fish than wild fish. Source apportionment demonstrated that the fossil energy consumption (coal combustion and vehicle exhaust), seawater, and metallurgic dust might serve as the possible main sources of heavy metals in seafood. Based on the policy scenario analysis, the fossil-energy-controlling policy and clean coastal water action were beneficial to the seafood safety by reducing target heavy metals in seafood. These findings provided comprehensive information on seafood safety and the water-food-energy nexus sustainability in coastal regions at continental-scale in terms of heavy metal pollution.

Determination of some minerals and heavy metal levels in Urfa cheese and cow's milk

This research was carried out to determine the levels of some minerals and heavy metals in Urfa cheeses and cow's milk offered for sale in Şanlıurfa. Mineral and heavy metal levels were determined by analysing 18 Urfa cheese and 21 cow milk samples collected from retail outlets with ICP-MS. Mean mineral and heavy metal contents in Urfa cheese samples were; magnesium (Mg) 129.8 ±31.14 mg/kg, calcium (Ca) 2712.66 ±1002.4 mg/kg, potassium (K) 272.06 ±127.21 mg/kg, titanium (Ti) 7.48 ±2.63 mg/kg, zinc (Zn) 40.4 ±16.33 mg/kg, selenium (Se) 10.6 ±3.51 mg/kg. In cow milk samples, average selenium (Se) 0.22 ±0.04 mg/kg, titanium (Ti) 0.07 ±0.009, mg/kg, copper (Cu) 0.0068 ±0.01 mg/kg and chromium (Cr) was detected at the level of 0.019 ±0.001 mg/kg. Arsenic (As), cadmium (Cd), lead (Pb) and thallium (Tl) levels were below the detectable levels in Urfa cheese and cow's milk samples. As a result, it was concluded that the samples do not pose a significant danger to public health in terms of heavy metal pollution and can contribute significantly to nutrition with the mineral substances it contains.

Enrichment, sources and ecological risk mapping of heavy metals in agricultural soils of dhaka district employing SOM, PMF and GIS methods

Rapid urbanization and industrial growth have triggered heavy metal contamination in agricultural soil in Dhaka, which is a serious concern for ecological risk and public health issues. In this study, fifty-four soil samples from agricultural lands of Dhaka had been analyzed for assessing accumulation, spatial enrichment, ecological risk and sources apportionment of heavy metals using a combined approach of self-organizing map (SOM), positive matrix factorization (PMF), geographical information system (GIS), and enrichment factor (EF). The results of the enrichment factor, geoaccumulation index and contamination factor index showed that more than 90% of the soil samples were polluted by higher levels of Cr and Cd. The mean pollution load index (PLI) results demonstrated that about 73% of soil samples were moderately polluted by heavy metals. Based on SOM and PMF analysis, four potential sources of heavy metals were found in this study area: (i) agrochemical and sewage irrigation (Cd–As); (ii) combined effect of agriculture, industrial and natural sources (Mn, Co, Ni and Zn); (iii) atmospheric deposition and industrial emission (As–Pb); (iv) chemical and leather tanning industries (Cr). The ecological risk index demonstrated that in terms of Cd content, about 75% of soil samples were moderate to high risk, and 20% were moderate to considerable ecological risk, which was the serious environmental, ecological, and public health concern. The spatial projection of ecological risk values showed that the southern part of Dhaka (Keraniganj Upazila) is a high ecological risk in terms of heavy metal pollution. These risk maps in agricultural soils may play a vital role in reducing pollution sources; so that zonal pollution control, as well as ecological protection, may be achieved in this resource-based agricultural land.

The potential use of waterworks sludge in greening: A bioassay with bermudagrass [Cynodon dactylon (L.) Pers.

Owing to the escalating production of waterworks sludge from growing population and water consumption, conventional options for the management of waterworks sludge may no longer be economically and environmentally viable. It is imperative to develop alternative measures for the sustainable management of waterworks sludge. This study explored the potential use of waterworks sludge as a soil substrate for greening through a bioassay with bermudagrass [Cynodon dactylon (L.) Pers.]. Treatments of the experiment varied with loading rates of waterworks sludge, soil types, and combined uses of fertilizers and peat moss. Several key findings were identified. First, the optimal rate of sludge application was approximately 25 % wt/wt, which was at least 1.5 times higher than the existing literature suggested. Second, it is necessary to add fertilizers and peat moss to make the sludge-loaded soil a suitable growing substrate for plants. The combined use of fertilizers and peat moss were more effective than fertilizers or peat moss used alone. Third, no significant environmental risk was ascertained, in terms of heavy metal pollution, when the loading rate of waterworks sludge was 25 % wt/wt. The results indicated waterworks sludge has a higher potential to be a soil substrate in greening, therefore, it could be a cost-efficient and safe surrogate to traditional measures.

Concentrations and sources of heavy metals in shallow sediments in Lake Bafa, Turkey

The concentrations and sources of heavy metals in shallow sediments in Lake Bafa were investigated. The concentrations of nine heavy metals and the total organic carbon content in sediment samples were determined for between Summer 2015 and Spring 2016. The mean contents of heavy metals were in decreasing order Fe > Mn > Ni > Cr > Zn > Cu > Co > Pb > Cd. Sediment quality guidelines indicate that Cr, Cu, and Ni pose a considerable threat to the aquatic ecosystem in Lake Bafa. Site L3 was found to be contaminated with Cd, Cr, and Ni, and the pollution load indices suggest that these metals had anthropogenic sources. The sediment samples were notably enriched with Cd and Ni. There is no consistent trend for seasonal effect in terms of the sample locations. However, at all sampling points, an increase in heavy metal concentrations was observed in the autumn. The results of a multivariate analysis indicate that the sources of Co, Cu, Fe, Mn, Pb, and Zn were all natural, the sources of Cd were anthropogenic, and the sources of Ni and Cr were both anthropogenic and natural. These results highlight that Cd, Cr, and particularly Ni represent the most serious threat in terms of heavy metal pollution in the ecosystem of the lake.

Applying of pollution indices as a monitoring tool for assessment of water quality in Tigris River, Baiji district, Salah alden governorate

This research has investigated the quality of surface water at Baiji district of Salah Alden governorate based on 5 sampling stations for two season (September 2012 and April 2013). Water evaluation indices (i.e. heavy metal pollution index (HPI), heavy metal evaluation index (HEI) and contamination degree index (Cd)) are utilized to characterize the quality of water in term of drinking purposes. All values of HPI were lower than (15), suggesting low heavy metal pollution. The values of HEI were also less than (10), indicating low heavy metal pollution, whereas Cd values were much less than (1) for all stations, indicating low heavy metal pollution. Consequently, Tigris River water in the study area is suitable for drinking purposes in terms of heavy metal pollution.

Applying of pollution indices as a monitoring tool for assessment of water quality in Tigris River, Baiji district, Salah alden governorate

This research has investigated the quality of surface water at Baiji district of Salah Alden governorate based on 5 sampling stations for two season (September 2012 and April 2013). Water evaluation indices (i.e. heavy metal pollution index (HPI), heavy metal evaluation index (HEI) and contamination degree index (Cd)) are utilized to characterize the quality of water in term of drinking purposes. All values of HPI were lower than (15), suggesting low heavy metal pollution. The values of HEI were also less than (10), indicating low heavy metal pollution, whereas Cd values were much less than (1) for all stations, indicating low heavy metal pollution. Consequently, Tigris River water in the study area is suitable for drinking purposes in terms of heavy metal pollution.
 
 http://dx.doi.org/10.25130/tjps.24.2019.089

Environmental impact of Gümüşhane City, Turkey, waste area in terms of heavy metal pollution

The aim of this study is to investigate the occurrence of a heavy metal contamination in a solid waste site of Gumushane City, Turkey, to examine the dimensions of the risk of contamination, and to present suggestions for possible solutions. For this purpose, heavy metal contents of soil and leachate samples taken from a Gumushane waste site were determined by a new method, microwave plasma-atomic emission spectrometry (MP-AES). When the obtained results are compared with background and control values, it can be seen that the region carries contamination risks, especially in terms of heavy metals such as Zn, Cd, Pb, Cu, Ni, and Co. To examine the environmental effects of the landfill area in more detail, geodeposition index (Igeo), enrichment factor (EF), contamination index (PI), and combined contamination index (IPI) parameters are used. In addition, the samples taken from an area supposed to be free of pollution risk were also analyzed as control samples, and the obtained data were statistically compared with the results of the waste area. It is determined that the results of landfill waste site are dissimilar to those of comparison samples in terms of investigated metals, and that they contained higher values in general.

Heavy Metal Pollution Around International Hatay Airport

In this study, it was aimed to determine the heavy metal pollution in the agricultural lands around Hatay airport and travel possible alteration in the amount of heavy metal on the land in accordance with the distance to the airport. For this purpose, the airport was chosen as the center and 27 soil samples were obtained around the airport at 2 km intervals in depth ranging from 0 to 30 cm. Lead (Pb), cadmium (Cd), nickel (Ni), chrome (Cr), cobalt (Co), aluminium (Al), iron (Fe), copper (Cu), manganese (Mn) and zinc (Zn) elements in soil samples were analysed using MP-AES instrument by DTPA method. (3 repetition for each sample). As a result of the analysis, heavy metal concentrations were found as Pb 0-1.45 mg/kg, Cd 0-0.220 mg/kg, Ni 0-3.95 mg/kg, Cr 0-0.780 mg/kg, Co 0-0.270 mg/kg, Al 0-0.700 mg/kg, Fe 1.47- 16.2 mg/kg, Cu 0.400-5.35 mg/kg, Mn 0-19 mg/kg and Zn 0.050-3.14 mg/kg. When comparing the obtained data through this study with allowable concentrations of heavy metals in soil of Environment and Forest Directorates Guidance, it was determined that the heavy metal concentration of the soil does not pose any problems in terms of heavy metal pollution. Besides, iron concentration was decreased when the distance to the airport is increased.

Geochemistry of Core Sediments from Tropical Mangrove Region of Tamil Nadu: Implications on Trace Metals

The present study aims to determine the concentrations of certain trace metals (Fe, Mn, Cr, Cu, Pb, Zn, Co, Ni, Ba, Sr, V and Rb) and to identify the possible sources of the trace metals with multivariate analyses and assess the metal contamination using the enrichment factor (EF) and geo-accumulation index (Igeo) from the two core samples taken from Pichavaram lagoon. Pichavaram mangrove is a dynamic intertidal environment lying in between Vellar and Coleroon estuaries in Cauvery delta along the east coast of India. High OM in the present study is noted in both core samples which are mainly controlled by productivity and sediment texture. The increase of trace metals concentrations was observed at lower intersects which indicates that the trace metals were reprecipitated around the redox boundaries. Further it signifies that the enrichment of metals in C1 core sample is closely related to the diagenetic. Factor 1 with significant positive loadings on Mud and good loadings on Fe and Mn suggests the associations of these metals with finer sediment fractions and aluminosilicates. These elements to be enriched in the clay fraction in both core samples. They are mainly related to anthropogenic inputs and reflect the complexing nature of the organic matter. Igeo studies confirm the contamination of the study area. Overall the study highlights significant anthropogenic contributions in terms of heavy metal pollution. Comparative data for normalized enrichment factors and the modified degree of contamination show that Pichavaram sediments have suffered significant systematic heavy metal contamination following catchment urbanization.

Metal accumulation and tolerance in wetland plants

This paper briefly reviews the progress in studies of wetland plants in terms of heavy metal pollution. The current research mainly includes the following areas: (1) metal uptake, translocation, and distributions in wetland plants and toxicological effects on wetland plants, (2) radial oxygen loss (ROL) of wetland plants and its effects on metal mobility in rhizosphere soils, (3) constitutional metal tolerance in wetland plants, and (4) mechanisms of metal tolerance by wetland plants. Although a number of accomplishments have been achieved, many issues still remain unanswered. The future research effort is likely to focus on the ROL of wetland plants affecting metal speciation and bioavailability in rhizosphere soils, and the development of rhizosphere management technologies to facilitate and improve practical applications of phytoremediation of metal-polluted soils.