Potential Ecological Risk Factor Research Articles

Environmental Assessment Impact of Acid Mine Drainage from Kizel Coal Basin on the Kosva Bay of the Kama Reservoir (Perm Krai, Russia)

The Kosva Bay is permanently affected by acid mine drainage (AMD) from Kizel Coal Basin in the Perm Krai of Russia. This discharge is released in the middle part of the Kosva River from the abandoned mines. This study investigates the current trace element (TE) concentrations for Zn, Cu, Pb, Ni, Cr, Cd, As, and Hg and the mineral composition, major oxides, grain size of sediments, and acute toxicity using two test organisms within the site of AMD downstream from the Kosva River and up to the Kosva Bay of Kama Reservoir. The objectives of this study were to analyze the quality of sediment and level pollution of Kosva Bay using pollution and ecotoxicological indices. The environmental indices, namely the contamination factor (CF), the geoaccumulation index (Igeo), and the potential ecological risk factor (Eri), indicate contamination by Cr and Pb in sediments at the site of AMD, with the highest values for Cr, Cu, and As in the Kosva Bay sediments downstream of abandoned coal mines. The results of Igeo and CF average values in bay of sediments showed different degrees of contamination, from moderate contamination to considerable contamination, respectively. According to the potential ecological risk index (RI) values, the Kosva Bay sediments exhibited low to moderate risk, and As and Cd have the highest contribution rate. According to LAWA and the Polish geochemical classification of sediments, sediments of the bay correspond to the highest levels (IV–III classes) for Cr, Ni, and Hg. Based on the SQGC, Hg, Cd, Cr, and Ni are the most probable for resulting in adverse effects on aquatic organisms in this study. The results of this study indicate that complex pollution and ecotoxicological indices must be supported by ecotoxicologal tests. High precipitation totals, low evaporation rates, and flow regulation stream by the Shirokovsky Reservoir located upstream from abandoned coal mines provide significant fluctuations in streamflow, which is probably the most important factor controlling the distribution and mobility of TE in the studied sediments.

Ecological Risk, Input Flux, and Source of Heavy Metals in the Agricultural Plain of Hebei Province, China.

A large amount of heavy metal (HM) inputs exists in the farming areas of the Hebei plain of northern China. However, the potential ecological risk, source, and input flux of HMs in these areas have not been well-investigated. In this study, atmospheric deposition, fertilizer, irrigation water, and agricultural soil samples were collected from farming areas (~74,111 km2) in Hebei Province, China. The HM index of geoaccumulation (Igeo) and potential ecological risk index (RI) of soil was calculated for eight HMs. The source and input flux of each element were predicted using the input flux and principal component score–multiple linear regression (PCS–MLR) methods. The results showed that Cd and Hg increased Igeo values, and the maximum levels of As (29.5 mg/kg), Cu (228.9 mg/kg), Cd (4.52 mg/kg), and Zn (879.0 mg/kg) were greater than the health risk screening values in the soil quality standard of China. The potential ecological risk factor (Er) of Cd demonstrated a moderately potential ecological risk, accounting for 67.72%. The distribution map showed that Cd was mainly concentrated in eastern area of Baoding (BD) in the study area. The result of the atmospheric dry and wet deposition contributed more to soil pollution than the usage of fertilizer or irrigation water by calculating the input flux. The order was Zn (94%) > Cu (92%) > Pb (89%) > Cr (86%) > Cd (72%) > Hg = Ni (71%) > As (59%). Principal component analysis (PCA) results showed that there were four sources of HMs in soil. Geological sources contribute to the accumulation of As, Cr, and Ni in soil. Cu and Pb in the soil were attributable to the input from vehicular emissions and irrigation water. Cd and Zn in the soil were attributable to the farming activity, whereas Hg originates from the combustion of coal. The results of PCS–MLR demonstrated that the contribution rate of As, Ni, and Cr in the study area was 30.06%, 71.86%, 57.71% for the first group (natural source); Cu, Pb and Zn were 71.78%, 63.59%, and 30.72% for the second group (vehicle emissions); Zn was 60.93% for the third group (fertilizer application and irrigation water); and Hg was 85.16%, for the fourth group (coal combustion). These factors provide a valuable reference for remediating HM pollution.

Spatial Characteristics and Potential Ecological Risk Factors of Heavy Metals in Cultivated Land in the Transition Zone of a Mountain Plain

The purpose of this study was to explore the spatial distribution characteristics and potential ecological risk factors of heavy metal pollution in cultivated soil in the transitional zone of a typical mountain plain. In this study, a county in Sichuan Province, which has the typical transitional topography of the Chengdu Plain-Longmen Mountain transition zone, was taken as the study area. Geostatistics and potential ecological risk index methods were used to analyze the spatial distribution of Cd, Cr, Cu, Pb, and Zn from cultivated land in the study area, and a potential ecological risk assessment was carried out. This was combined with geographical detector analysis to further explore the main influencing factors leading to the spatial difference in potential ecological risk. The results showed that:① The average values of ω(Cd), ω(Cr), ω(Cu), ω(Pb), and ω(Zn) of cultivated land in the study area were 0.39, 123.00, 31.28, 51.04, and 119.66 mg·kg-1, respectively, which were more than 2.60, 1.59, 1.19, 2.00, and 1.54 times the soil background value in the study area. ② The high value areas of Cd and Cr in cultivated land in the study area were mainly distributed in the west of the mountain area, the south of the transition zone, and the west of the plain area; the high value areas of Cu and Zn were mainly distributed in the west of the mountain area; the high value areas of Pb were mainly distributed in the south of the transition zone and the west of the plain area; and the low values of the five heavy metals were mainly distributed in the north of the transition zone. ③ The soil of cultivated land in the study area was dominated by slight potential ecological risk, and the average value of potential ecological risk index of heavy metals was Cd(32.58) > Pb(3.12) > Cu(2.82) > Cr(1.58) > Zn(0.98). Cd was the main factor causing the potential ecological risk of cultivated land in the study area. ④ There were significant differences in the key influencing factors of soil potential ecological risk of cultivated land in different topographic regions of the study area. The distance from the river and the soil type were the key factors affecting the mountain area; the multiple cropping index and the distance from the industry and mine were the key factors affecting the transition zone, and the soil pH value and the amount of chemical fertilizer were the key factors affecting the plain area.

Assessment of the Heavy Metal Contamination of Roadside Soils Alongside Buddha Nullah, Ludhiana, (Punjab) India.

The present study was carried out to determine the physico-chemical characteristics and heavy metal contents in roadside soil samples collected during 2 sampling periods (September 2018 and April 2019) from 8 different roadside sites lying parallel to the Buddha Nullah, an old rivulet, flowing through Ludhiana, (Punjab) India. The contents (mg/kg) of seven metals (cadmium, chromium, cobalt, copper, lead, nickel and zinc) were estimated using a flame atomic absorption spectrophotometer. Among the metals analyzed, the contents of Cd, Co, Cu, Pb and Zn were found above the permissible limits. The results of the index of geoaccumulation (Igeo), contamination factor (CF), contamination degree (Cdeg), modified contamination degree (mCdeg), the Nemerow pollution index (PI) and pollution load index (PLI) indicate a moderate to high heavy metal contamination of the analyzed soil samples. The results of the potential ecological risk factor (ERi) and potential ecological risk index (RI) indicate a low to moderate risk of heavy metals in the studied soil samples. The Pearson correlation analysis revealed that most of the variables exhibited a statistically significant correlation with one or more variables during the two samplings. Multivariate analysis demonstrates that contents of heavy metals in the study area are influenced by anthropogenic and geogenic factors.

Source identification and health risk assessments of heavy metals in indoor dusts of Ilorin, North central Nigeria.

Exposure to heavy metals (HMs) in indoor dusts is a serious public concern that is linked to a myriad of deleterious health outcomes. The objectives of this study are to estimate the contamination levels of HMs in indoor dusts of different residential areas in Ilorin, Nigeria; identify HMs sources in different residential areas; and evaluate human health risks of HMs in selected residential areas. Indoor dust sampling was conducted in ten randomly selected from low, medium and high population density residential areas of Ilorin, Nigeria. Ten HMs concentration levels, their health risk implication and the associated potential ecological risks were evaluated. The mean concentration levels measured for Fe, Pb, Zn, As, Co, Cr, Cu, Cd, Mn and Ni were 38.99, 5.74, 3.99, 0.08, 2.82, 2.13, 0.47, 0.60, 6.45 and 1.09mg/kg, respectively. Positive Matrix Factorization (PMF) model was applied to ascertain sources of HMs in sampled indoor dust. Percentage contribution from oil-based cooking (29.82%) and transportation (29.77%) represented the highest source to HM concentrations among the six factors identified. The results of the various pollution indices employed showed that Pb, Zn, As, Co, Cr, Cu, Mn and Ni contributed moderately to HMs concentration levels in the sampled dusts. Cd had highest potential ecological risk factor of between 160 and 320. The average values of Enrichment Factors (EFs) obtained aside from Fe used as the reference metal, ranged between 8.46 (As) and 2521.61(Cd). Health risk assessment results revealed that children are the most susceptible to the risks associated with HMs bound indoor dust than the adults. The percentage risk contributions of Hazard Quotient via ingestion route (HQing) in Hazard Index (HI) for non-cancer risk of indoor HMs were 93.17% and 69.87% in children and adults, respectively. Likewise, the percentage cancer risks contribution through ingestion pathway (CRing) were higher than cancer risks through inhalation and dermal pathways (CRinh and CRdermal), accounting for 99.84% and 97.04% of lifetime cancer risk in children and adults, respectively. The contamination level of Cd recorded is of great concern and signifies very strong contribution from anthropogenic sources. This study has further revealed the levels of HMs in typical African residential settings that could be used by relevant stakeholders and policy makers in developing lasting control measures. The online version contains supplementary material available at 10.1007/s40201-021-00778-8.

Potential Ecological Risk Assessment of Heavy Metals in Cultivated Land Based on Soil Geochemical Zoning: Yishui County, North China Case Study

Various human production activities have caused tremendous damage to the soil ecological environment of cultivated land. Regional ecological risk assessments and the safe use of cultivated land have received widespread attention. The ecological risk assessment of heavy metals based on soil geochemical zoning has not been reported in the past. Using 14,389 topsoil samples, considering comprehensive geological background information, Yishui County in northern China was divided into three soil geochemical areas and 14 soil geochemical sub-regions by means of principal component factor superposition. The results of environmental quality and risk assessments of eight heavy metals based on soil geochemical zoning show that the single pollution index was greater than 1.0 and the Nemerow pollution index was greater than 0.7 for Ni in a sub-region, indicating that Ni pollution had reached the early warning limit, which demonstrates that Ni has a certain enrichment trend. Meanwhile, the geoaccumulation index of Ni and Cr was greater than zero in some sub-regions, indicating a slight pollution level. In addition, the potential ecological risk factor of the measured heavy metals was greater than 40 in 9 sub-regions, indicating a moderate ecological hazard, and the risk index was greater than 150 in a sub-region, revealing moderate ecological intensity, in which Hg and Cd were leading contributors to potential ecological hazards with a contribution rate between 58% and 76%. This method is suitable for the evaluation of soil environmental quality and safety for medium and large scales, and can provide a scientific basis for further zoning and grading prevention and control of soil pollution in cultivated land.

Ecological risk assessment of trace metals in sediment from the Old Brahmaputra River in Bangladesh

ABSTRACT The assessment of trace metal contamination in river sediments is crucial for suggesting effective strategies to protect aquatic ecosystem health. In this study, six toxic trace metals (As, Cd, Cr, Hg, Ni and Pb) in the surface sediments from the Old Brahmaputra River in Bangladesh were examined to evaluate the potential ecological risks. Sediment samples were collected in September 2018 and analysed by an atomic absorption spectrometer. Mean concentrations (mg/kg dw) of trace metals were in the order of Ni (43.49) > Cr (30.25) > Pb (14.29) > As (3.74) > Hg (0.16) > Cd (0.03). Spatially the sedimentary metals did not vary significantly. Source analyses revealed anthropogenic origin for most of the metals. The contamination factor, enrichment factor and geoaccumulation index (I geo) revealed a low degree of contamination for all cases except Hg, which showed a moderate degree of contamination. According to the sediment quality guidelines and sediment screening values, only Cr, Hg and Ni were high enough to cause detrimental effects in aquatic organisms. The potential ecological risk factor (Er i ) and potential ecological risk also revealed low to moderate ecological risk. Comprehensively, the river was in the uncontaminated to moderately contaminated level with low ecological risk.

Hygienic quality of soil in the Gemer region (Slovakia) and the impact of risk elements contamination on cultivated agricultural products

The Gemer region (Slovakia) belongs to areas with a high concentration of risk elements. The contents of Cu, Ni, Pb, Cd, Hg and Mn were determined in soils and cultivated agricultural production from lands in three cadastres of the Gemer region (Henckovce (48.713845, 20.426189) and Nižná Slaná (48.717373, 20.4208423), cultivated crop—spring triticale; Gemerská Poloma (48.704523, 20.487645), cultivated crop—maize). Bioavailable forms of Pb (0.306–0.532 mg/kg) and Cd (0.104–0.154 mg/kg), pseudototal forms of Cd (3.07–3.98 mg/kg) and Hg (0.484–2.18 mg/kg) represented the highest risk in soils. The highest contents of Pb (Cd, Hg) were in maize from Gemerská Poloma: 0.898 (0.081, 0.399) mg/kg DM. Soils were classified based on several indicators of soil contamination. The highest values of indicators are: Contamination factor (Cf 29.1—Hg), Degree of contamination (Cdeg 51.5), Potential ecological risk factor (Er 1163—Hg), Potential ecological risk index (RI 1,520), Pollution load index (PLI 4.76), Geo-accumulation index (Igeo 5.60—Hg). All indicators concerned the lands of Henckovce and Gemerská Poloma, RI also concerned the land of Nižná Slaná. Bioaccumulation factor (BAF) was calculated to assess the plant's ability to absorb the risk element. For both crops and all risk elements, BAF values were < 1. Obtained results indicate heavy metal contamination of soils, therefore monitoring of soils in investigated area is necessary.

Heavy metals accumulation and risk assessment in a soil-maize (Zea mays L.)system around a zinc-smelting area in southwest China.

Smelting of nonferrous metals causes significant concerns because of its emissions of heavy metals (HMs) into surface soil, and its potential threat to human health through the food chain. To investigate the HMs concentrations in a soil-maize system, a total of 41 paired soil-maize samples were collected from a typical indigenous zinc-smelting area of northwestern Guizhou Province, China. Results showed that the concentrations of the targeted HMs in the soil were significantly higher than their corresponding background values of Guizhou Province. Results obtained of the geo-accumulation index (Igeo) and the potential ecological risk factor of an individual metal (E r i ) revealed that Cd and Pb were identified as the top-priority control HMs in the study area. The mean concentrations in maize grain decreased in the order of Zn > Pb > Cu > Cd. Bio-accumulation factor (BAF) indicated a strong ability for Cd to be accumulated in the maize root. Translocation factor (TF) and Fourier transform infrared (FTIR) spectroscopy revealed that the maize root played an important role in reducing the mobilization of HMs to stem, except for Zn. Kriging interpolation results illustrated that the spatial distribution patterns of HMs in the maize grain were generally similar to those in sampled soil, and the higher concentrations for the investigated HMs were partially overlapping between soil and maize grain. The average hazard quotient (HQ) of the investigated HMs for both children and adults were all lower than the threshold value (HQ = 1). The total hazard index (HI) was 5.51E-01 and 4.24E-01 for the two population groups, respectively, implying no potential non-carcinogenic risk for local maize-consumers. Sensitivity analysis demonstrated that the oral ingestion rate (IngR) of grain was the predominated contribution to the output of the risk assessment.

Multivariate geo-statistical perspective: evaluation of agricultural soil contaminated by industrial estate's effluents.

Present study was carried out to explore heavy metals pollution and potential ecological risk factors associated with agriculture soil irrigated with industrial effluents of Hayatabad industrial estate, Peshawar (HIEP) and Gadoon industrial estate, Sawabi (GIES) of Khyber-Pakhtunkhwa, Pakistan through multivariate geo-statistical tools. Diverse statistical tools like cluster analysis (HC) and principal component analysis (PCA), along with geo-statistical approaches were applied to highlight the geogenic and anthropogenic sources of pollution. The results indicated that concentration of heavy metals in target areas was significantly higher than control. Both soils had significant to moderate enrichment of heavy metals, while Gadoon soil had moderate to considerable ecological risk factor. The geo accumulation indices (Igeo) tendency for heavy metals in both target soil (Gadoon and Hayatabad) were the same. The Pb concentration of both target areas falls in the extremely severely polluted category because of the excessive presence of industries producing lead-containing products. Hence, this study indicated that the majority of toxic heavy metals contributed to soil pollution in the studied areas are coming from industrial and commercial activities.

Diversification of Dawkinsia filamentosa (Valenciennes, 1844) and their growth conditions by the impact of toxic metals in the river Tamiraparani.

The concentration of toxic metals in water, sediment, and organs of species Dawkinsia filamentosa and its growth conditions were analyzed from the Tamiraparani river of Tamilnadu, India. The water quality preferred to examine the existence of metals, and the concentration of Pb, Cr and Cd expand the first time were found to be high in sediment, which was followed by water and the organs of the fish gill and liver. Even though, intakes of the toxic metals were highly accumulated in the gill instead of the liver. From that, the histological assessments of organ damages were observed significant variations in the study sites. Within the linear regression parameters for length-weight relationships of coefficient value r2, 'a' value and 'b' value were showed the allometric growth rate and condition factor of 'K' was fittest. The phylogenetic tree analyses were showing analogy between the opposite groups of Clade III and Clade II showed that the species were closely correlated with the Puntius sp. of other species. And in Clade I was intimately related within the identical population of D. filamentosa as respectively. However, the comparison of metal concentrations of other Indian rivers and of other parts of the world specified that these metals are getting closer to the standard permissible limits. Altogether, the potential ecological risk factor was slightly increased at the sampling sites; therefore, we conclude that the metal contents might pollute the river. Throughout this research, the observed findings emphasize that fish species from the riverine ecosystem may useful for environmental management and genetic diversity.

Evaluation of the Pollution Status of Lagos Coastal Waters and Sediments, using Physicochemical Characteristics, Contamination Factor, Nemerow Pollution Index, Ecological Risk and Potential Ecological Risk Index

The heavy metals and physicochemical properties of Lagos coastal waters and sediments, Southwestern Nigeria were investigated in 5 stations (station 1-5), to determine their levels, distributions and pollution index. The observed ranges of physicochemical characteristics from the study area are: dissolved oxygen (DO): 2.15-11.3 mg/L; pH: 6-7.7; temperature (Temp): 28.05-29.25°C; biochemical oxygen demand (BOD): 1.6-110.1 mg/L; electrical conductivity (EC): 1.8-29.8 mS/cm; salinity (SAL): 0.02-2.05ppt; total dissolved solids (TDS): 211.8-1210.2 mg/L and total suspended solids (TSS): 12.13-117.95 mg/L. The analyzed physicochemical properties from all the stations are within the desired values for healthy marine ecosystems when compared with Federal ministry of environment (FMENV) Nigeria and World Health organization permissible limits (DO:&gt;5 mg/L; pH:6.5-9; TEMP:&lt;40°C; BOD: 50 mg/L; EC:900 mS/cm; TDS:1000mg/L and TSS:600 mg/L), with the exception of low DO at station 1 and station 5; and high BOD at; station 2 and station 3 respectively. The concentrations of heavy metals present in the water samples followed the sequence: Fe &gt; Pb &gt; Cu &gt; Cr &gt; Zn &gt; Cd, and showed high values for Pb, Cd and Cr, relative to the standard permissible limits according to FMENV (Pb 0.001; Zn 50 mg/L; Cd &lt; 0.0018; Cu 2-4 mg/L and Cr 0.02-2.0 mg/L). The calculated contamination factor (CF) in the sediment samples showed low-moderate contamination for the analyzed heavy metals (Cr, Zn, Cu and Pb), except for cadmium (Cd) that showed extremely severe contamination (CF &gt; 6) values across the sampling stations. The calculated Nemerow pollution index (NPI) and ecological risk index (RI) showed heavily polluted (NPI &gt; 10) values and very high ecological risk (RI &gt; 380) values at Apapa (location 1), Iddo (location 2) and Makoko (location 3). The potential ecological risk factor (Eir) confirmed Cd as the highest polluted heavy metals (Eir &gt;320), with the greatest potential threat to the marine ecosystems in the Lagos coastal waters. The study highlights the impacts of anthropogenic pollutions on the coastal ecosystems and human health.

Heavy Metal Pollution and Ecological Risk Assessment in Soils Adjacent to Electrical Generators in Ramadi City, Iraq

This study aims to evaluate the concentration of the heavy metals (Co, Cd, Cr, Cu, Ni, Pb, and Zn) and their ecological risk in soils adjacent to the power generators of Ramadi city, Iraq. The soil samples were collected from a depth of 20cm. The obtained results showed that the mean concentrations of heavy metals (HMs) are ranked as in the following order: Cr (360.90mg/kg) &gt; Ni (283.65mg/kg) &gt; Zn (190.96mg/kg) &gt; Pb (130.75 mg/kg) &gt; Cu (36.54 mg/kg) &gt; Co (16.62 mg/kg) &gt; Cd (2.55 mg/kg). The mean values of HMs concentration exceed the international guidelines. The result of correlation matrix analysis at P £ 0.05 showed significant correlations between the concentrations of HMs. These correlations are interpreted in the context of a common source of pollution and/or common origin. Results of the potential ecological risk factor assessment of metal i (Eir) in soil adjacent to the power generators of Ramadi city showed that the Eir values take the following descending order: Ni (354.56, very severe) &gt; Cd (255.31, severe) , Co (207.77, severe) &gt; Zn (88.69, heavy) &gt; Cu (25.73, light) &gt; Cr (17.43, light) &gt; Pb (12.0, light). The potential ecological risk index (RI) values are classified as severe ecological risk for all studied heavy metals. This study provides the environmental protection managers and decision-makers with important information about the risk of using electrical generators in residential neighborhoods.

Vertical distribution and contamination assessment of heavy metals in sediment cores of ship breaking area of Bangladesh.

Vertical heavy metal profiling reflects the history of the deposition of metals and helps to understand the characteristics of accumulation in various layers of the sediment. Nevertheless, no previous studies in Bangladesh had focused on the vertical distribution of heavy metals in core sediments. In this study, vertical distribution, contamination level and potential ecological risks of six heavy metals (Zn, Cu, Pb, Cr, Ni, Mn) from the core sediment of ship breaking were assessed and compared with the non-ship breaking area of Bangladesh. The concentration (µg/g) of heavy metals in the 0-10cm (surface), 10-20cm (middle) and 20-30cm (bottom) of sediment cores was as follows, respectively: Zn (35.54-100.68, 37.27-258.02, 42.78-66.45); Cu (16.38-75.25, 30.64-92.02, 34.99-52.98); Pb (4.84-132.08, BDL-204.48, BDL-23.51); Cr (14.57-42.13, 25.31-42.71, 15.26-36.34); Ni (4.02-42.23, 4.94-43.70, 4.40-43.13); Mn (198.74-764.16, 257.77-980.50, 255.62-856.44). The heavy metal content of core sediment from the shipbreaking region was substantially higher than that of non-shipbreaking area. Except for Ni, heavy metal content was highest in the middle layer, followed by the upper and lower layers of the sediment core. Contamination exponents such as enrichment factor, contamination factor and geo-accumulation index (Igeo) revealed contamination by Zn, Cu and Pb while potential ecological risk factor ([Formula: see text]) and risk index suggested low ecological risk by studied heavy metals except for Pb. Correlation matrix, cluster analysis and principal component analysis indicated that all studied heavy metals could have similar anthropogenic origins.

Comparing Levels of Some Heavy Metals in Rivers and Sediments from Two South-Western States of Nigeria

Ten water and ten sediment samples from both Igbokoda and Apapa in South west, Nigeria were collected between March and August, 2018 for heavy metal analysis. The study aimed at using Potential Ecological Risk (PER) index to characterize rivers sediments and waters for possible environmental impact. The sampling span industrial, domestic and recreational areas. The water and sediment grab samples were treated using standard procedures. The filtrate from sediment was made up to 50 cm3 mark with distilled water and used for seven heavy metals determination using atomic absorption spectrophotometry (AAS). Contamination factor (CF) and Pollution load index (PLI) calculated for each metal in the sediments indicate moderate contaminations. However, Cd in exception showed the highest potential ecological risk factor of 42.3 in Igbokoda. PER value of the Igbokoda sediment is 45.37 while that of Apapa sediment is 6.79. The potential risk pose by Cd alone in the sediment suggests that the Igbokoda water is unsafe for recreational and other beach activities. The recommendation from the study will suggest a proper treatment of wastewater and sewages before fluxing into both the Igbokoda and Apapa water bodies

Evaluation of Soil Contamination by Heavy Metals in the Vicinity of Boucaid Mine, Ouarsenis (N.O. Algeria)

ABSTRACT The long mining activities in Ouarsenis region can be the soil pollution source around the mine. For this reason, for the first one, seven heavy metals collected from the mine and its surroundings are calculated to know the source of these heavy metals and evaluate their contamination in the study area. The means concentration of studied heavy metals vicinity to Boucaid mine range between 2.91 and 92.72 mg.kg−1, the high value is recorded for Pb and the low for Zn. The means concentration of seven heavy metals in the mine varies between 3.35 and 168.52 mg.kg−1. The concentration of samples collected in Sidi Slimane have high concentration of Pb than other sites. The means concentration of Mn, Pb, and Cd are higher than background values and in the mine than study area, which suggests their anthropogenic source. The geoaccumulation index values of Cr, Cu, Pb, Mn, Ni, and Cd are low to zero, which indicated that the study area is uncontaminated by these heavy metals. The index of potential ecological risk factors is 80.86, which is less than 150, showed low potential ecological risk. The principal component analysis and hierarchical cluster analysis confirm the mixed anthropogenic sources of heavy metals.

Distributions, temporal trends and ecological risks of polyethylene terephthalate (PET) and di-(2-ethylhexyl) phthalate (DEHP) in sediments of Jiaozhou Bay, China

Spatiotemporal distribution and ecological risk of the polyethylene terephthalate (PET) plastic polymer and plasticizer di-(2-ethylhexyl) phthalate (DEHP) were investigated using both surface and core sediments in Jiaozhou Bay, China. The concentrations of PET and DEHP ranged 210.6–1929.7 μg/kg and 0–591.2 μg/kg, respectively. The depth profiles of PET and DEHP in the sediment cores indicated that PET and DEHP pollution increased since the 1970s, which is in accord with the regional PET and DEHP consumption history. The levels of PET in Jiaozhou Bay was found to represent low ecological risk based on the assessment models for Potential Ecological Risk factor and Potential Ecological Risk. The amounts of DEHP also posed a low risk to the aquatic organisms in the sediment phase as indicated by the Risk Quotient method.

Mapping heavy metal (Cu, Zn, and Pb) pollution and ecological risk assessment, in the surroundings of Gabes cement plant—Tunisia

The pollution and contamination assessment of three heavy metals (Cu, Pb, and Zn) in the topsoil, and common plants (Olea europaea, Prunus persica vulgaris, Ficus carica, Medicago sativa, Zygophyllum album, and Helianthemum kahiricum) were carried out at different distances from a cement plant. This evaluation was based on four evaluation methods: Bioconcentration factor, Contamination factor, Geoaccumulation Index and Potential ecological risk factor. The chlorophylls a and b contents were also analyzed. The highest levels of Cu, Zn, and Pb in the topsoil were found close to the cement factory (cluster D), and the lowest values were observed in a distant oasis (cluster H). The lowest chlorophylls values were observed in perennial plants (O. europaea and F. carica) near the cement plant. Zygophyllum album and H. kahiricum showed capability to remove Cu an Zn in contaminated locations, depending on the soil type. The spatialization of the results was essential to the understanding of the potential contribution of different sources of Cu, Zn, and Pb in the topsoil and to distinguishing different behaviors of the same plant species. Concerning H. kahiricum, further research should be undertaken since it has a high livestock acceptability index and is used in traditional medicine. Novelty statement The impact of three heavy metals (Cu, Zn, and Pb) on the topsoil and six species of plants common in Tunisia (arid climate) will be assessed, and the potential contribution of different sources to the contamination. Few studies have addressed the impact of cement dust in the topsoil and common plant species in arid rangelands, and, as far as we know, none of them have considered the spatialization of the data and results, considering the prevailing wind, plant species location, soil type, and use. Moreover, the ability of steppic vegetation to remove these three heavy metals (phytoextraction) was evaluated using the bioconcentration factor (BCF), soil pollution indices, and ecological risk. Chlorophylls a and b contents were also evaluated to establish the effect of the cement plant on the health of plants located nearby.

Concentrations, distribution, and risk assessment of heavy metals in the iron tailings of Yeshan National Mine Park in Nanjing, China

For the first time, a field survey was conducted to investigate the present situation, vertical distribution and ecological risks of heavy metals (Cu, Zn, Mn, Cr, Pb and As) from 21 in-situ samples drilled out from Yeshan iron mine tailings in the Jiangsu Province of China. The heavy metal contents obtained for the tailing wastes in decreasing order were as follows: Mn > Cu > Zn > As > Cr > Pb. The contents of heavy metals varied with depth, and the variation trends were not completely consistent. Vertical distribution profiles showed that heavy metals accumulated in certain strata. Both the monomial potential ecological risk factor (E) and the risk quotient (RQ) showed a high ecological risk for Cu, Mn and As. The comprehensive ecological risk index (RI) also indicated that the wastes presented a high ecological risk level, to which Cu, Mn and As were the key contributors. Our study showed that the health of individuals, especially children, living in the mining-impacted areas could be affected by the potential noncarcinogenic risk of copper, manganese and the carcinogenic risk of arsenic.

Pollution status, spatial distribution and ecological risk of heavy metals in sediments of a drinking water lake in South Eastern China

ABSTRACT This study investigates the pollution status, spatial distribution of heavy metals including Cr, Mn, Ni, Cu, Zn, As, Cd and Pb, in sediments from the Longhu Lake, and evaluates possible ecological risk of these metals. Average concentrations of Cu, Zn, Cd and Pb were 2.1, 3.5, 8.0 and 2.5 times higher than Grade I Chinese soil quality standard respectively. The geo-accumulation index indicates that the lake sediments are moderate to heavily contaminated by Zn, Cd and Pb, which may have higher toxic effects than other metals. The potential ecological risk factor (E i r) suggests low risk to aquatic organisms except for Cd which has a considerable risk to aquatic biota. Spearman correlation and principal component analysis suggest that Mn, Zn, Cd and Pb possibly having similar anthropogenic sources and behaviors in the lake. Overall, this study suggests that anthropogenic inputs are from local point and non-point sources, runoff and atmospheric deposition.