Ecological Risks Of Cu Research Articles

Appraisal of metallic pollution and ecological risks in agricultural soils of Alborz province, Iran, employing contamination indices and multivariate statistical analyses

ABSTRACT The current study was done to evaluate the pH, electrical conductivity, bulk density, sand, silt, clay, available K and P, organic carbon, Zn, Cu, Mn, and Fe in agricultural soils of Alborz province, Iran. A total of 46 samples were collected as composite samples from 0–20 and 20–40 cm soil depths. The average values of Fe, Cu, Mn, and Zn were found lower than the European limits, Indian limits, and Earth’s crust. Pearson’s correlation analysis found that pH effects Zn retention and, Cu and Mn retention in soil samples. Cluster analysis and Principal component analysis established that HMs are originated from different sources. Contamination factor (CF) and ecological risk index (RI) results showed less contamination and ecological risk in soil samples. Enrichment factor (EF) and modified ecological risk index (MRI) results indicated high enrichment and ecological risk of Cu, Mn, and Zn in surface and sub-surface soil samples.

The combined effect of phytostabilization and different amendments on remediation of soils from post-military areas

Army bases and battle fields are areas of high pollution due to the chemicals released there. Soils in these areas suffer from these uses of the land, and ecosystem services are affected. Although, in the 20th century, the production of bombs and the locations of battle fields and army bases were widespread, there is little research on the impact of war on nature. Moreover, there is a need to rehabilitate the disturbed soils. The contents and ecological risks of Cu, Ni, Cd, Pb, Zn, and Cr in the topsoil from a post-military area (north-eastern Poland) were investigated. In addition, a vegetation experiment was performed with the technique of aided phytostabilization on soils from the study area. The novelty of this study is the assessment of the usefulness of soil amendments (chalcedonite, limestone, activated carbon) in heavy metal (HM) phytostabilization in contaminated soils from post-military areas. Soil samples were also examined for pollution quantification indicators, including the index of geoaccumulation (Igeo), contamination factor (CF), and degree of contamination, and subjected to the Ostracodtoxkit test. The mean contents of the tested HMs were higher than those stipulated in soil environmental quality standards. The highest Igeo (7.38) and CF (346) values were those of Cr and Zn, respectively. The highest increase in soil pH was observed after the application of limestone to the soil. The greatest reduction in Cu, Ni, and Cd contents was caused by addition of limestone. The contents of HMs in Festuca rubra were higher in its roots than in its above-ground parts.

Concentration and Ecological Risk Assessment of Heavy Metals in PM2.5 Collected in Urban and Suburban Areas of Beijing

Atmospheric PM2.5 pollution and ambient air quality were investigated in Beijing, and the ecological risks of the trace heavy metals in PM2.5 were analyzed. PM2.5 samples were collected from Dongzhimen and Huairou by a middle volume sampler, and 16 kinds of trace metals were determined by inductively couple plasma-mass spectrometry (ICP-MS). The results showed that the average concentration of PM2.5 in the urban area was 92.35 μg·m-3, and the number of days higher than the Ambient Air Quality Standards (GB 3095-2012) accounted for 41.7% of the total number of days. The average concentration of PM2.5 in the suburban area was 70.90 μg·m-3, and the standard exceedance rate was 31.7%. In general, the spatial and temporal distributions of heavy metals were as follows:nighttime > daytime; urban area > suburban area; winter > autumn > spring > summer. The enrichment factors for Pb, As, Zn, Ni, and Cu in the urban area and Pb, As, Zn, Cr, Ni, and Cu in the suburban area indicated that most came from anthropogenic sources. The result for the geoaccumulation index indicated that Ni is affected by anthropogenic sources and natural resources, while Cu, Zn, As, Cd, and Pb might have been derived from human activities. The potential ecological risk of Cu, Zn, Pb, and Cd was high, while the degree of ecological harm posed by Cd was extremely strong.

Mobility and potential ecological risk assessment of copper and zinc in alluvial and marine soils in the North Nile Delta, Egypt.

COPPER (Cu) and zinc (Zn) are micronutrients needed for organisms, however, they are heavy metals and may become toxic to the organisms when exceeding the allowable limit in the environment. Two soil types of marine and alluvial were sampled in the North Nile Delta, Egypt. Copper (Cu) and zinc (Zn) were analyzed to investigate the availability and to evaluate ecological risk assessment and identify pollution sources. Cu and Zn were extracted from soil samples by DTPA-TEA. The higher content of Cu was recorded in alluvial soil, especially in the surface, while Zn concentrations in both soils didn’t differ with depth. Six indices were used in this study to evaluate the potential ecological risk of Cu and Zn in the examined soils. The results of these indices revealed that affecting Cu and Zn anthropogenically in some profiles of the studied soils. As well, the results of principal component analysis (PCA) showed that Cu and Zn in marine soils mainly originated from anthropogenic source, while this is true in alluvial soil in Zn only. Human and agricultural activities may be the main source of Cu and Zn especially fertilizers and pesticides, which indicates that there may be environmental threating by those metals in the study area in the future.

Effects of planting patterns on the concentration and bioavailability of heavy metals in soils during wetland restoration

To understand the effects of planting patterns on heavy metals in soils, the total concentration, bioavailability, contamination level, and ecological risk of heavy metals in soils from Jinjiang Estuary wetland were investigated. The results showed that after a wetland restoration, the concentrations of Cu were as follows: before wetland restoration > after wetland restoration > control group. The concentrations of Cr and Pb before and after the wetland restoration were all higher than those of the control group, whereas only some of the values of Zn were higher than those of the control group. Likewise, the bioavailability of Cu was roughly the same as that of the control group, those of Cr and Zn were higher than those of the control group, and that of Pb was less than that of the control group. Generally, after the wetland restoration, the bioavailabilities of Cu, Cr, and Pb decreased, but that of Zn increased. Moreover, the pollution level and ecological risk of Cu decreased, while those of Cr, Zn, and Pb increased. In addition, the comprehensive potential ecological risk of the Jinjiang Estuary wetland was moderate for Cu, Cr, Zn, and Pb before and after the wetland restoration. These results suggest that during a wetland restoration, the mixed vegetation types and planting density could influence the total concentration and bioavailability of heavy metals, affecting the pollution level and ecological risk of heavy metals to some extent. This study would be helpful in providing subsequent scientific research to restore wetlands.

Effects of Planting Patterns on Trace Metals in Soils Following Wetland Restoration

To understand the effects of planting patterns on trace metal fractions in degraded wetland soils in the Jinjiang Estuary, the chemical speciation of trace metals (Cu, Cr, Zn, and Pb) before and after wetland restoration is analyzed based on a measurement and testing program. The results show that wetland restoration, in general, increases the ratios of Cu, Cr, Zn, and Pb in the acid‐soluble fraction and the ratios of Cr, Zn, and Pb in the residual fraction and decreases the ratios of Cr, Zn, and Pb in the reducible fraction and the ratios of Cu, Cr, Zn, and Pb in the oxidizable fraction; thus, the mobility of Cu increases, and the mobility of Cr, Zn, and Pb decreases. Moreover, the planting patterns influence the levels of Cu, Cr, Zn, and Pb to some extent. After wetland restoration, the levels of Cu show an upward trend, and the Pb levels exhibit a downward trend. However, the potential ecological risk of Cu, Cr, Zn, and Pb fail to decrease. The restoration time may have been too short. The results of this study indicate that the planting patterns influence the transformation of trace metal fractions in soil and affect the pollution degree and potential ecological risk, contributing to a better understanding of the effects of planting patterns on trace metals following wetland restoration. The results will be helpful for subsequent scientific research on wetland restoration.

Speciation, Fate and Transport, and Ecological Risks of Cu, Pb, and Zn in Tailings from Huogeqi Copper Mine, Inner Mongolia, China

Tailings collected from the tailing reservoir at Huogeqi Copper Mine, located in Inner Mongolia, China, were used in a leachate study to evaluate the acid potential, neutralization potential, and possibility for producing acid mine drainage (AMD) from the site. The speciation of Cu, Pb, and Zn contained in the tailings was also determined during the leachate study to further access the potential migration abilities of these metals. The results showed that the tailings did not produce significant AMD as the pH of the leachate ranged from 7 to 9 and decreased with time. The Cu, Pb, and Zn concentrations were high, ranging from 439.1 to 4527 mg/kg in the tailings and from 0.162 to 7.964 mg/L in the leachate, respectively. Concentrations of metals in the leachate and tailings were positively correlated. Over 60% of the Cu in the tailing samples existed in an oxidizable form. Most of the Pb also existed in its oxidized form, as did the silicate and Zn. Metals usually have higher mobility in their exchangeable and oxidizable forms and as such represent a higher potential risk to the environment. Results of risk assessment code also revealed that metals in tailings exerted medium to high risks to the environment.

Copper and zinc, but not other priority toxic metals, pose risks to native aquatic species in a large urban lake in Eastern China

Over the past 20 years, global production of copper (Cu) and zinc (Zn) rank in the top three compared to other metals such as Pb, Cd, Cr, Ni, As and Hg. However, due to the potential for exposure and toxicity to humans, more attention of environmental pollution was paid to other metals such as Cd and Hg. Aquatic organisms are sensitive to Cu and Zn. Even though internal concentrations of these required elements are homeostatically controlled, toxic effects can occur at the fish gill surface. In this work, concentrations in surface waters and toxic effects of Cu, Zn, Ni, Cr, Pb, Cd, As, Hg were determined and risk of various metals in Tai Lake, China were evaluated using both risk quotients and joint probability distributions. Two transition metals, Cu and Zn posed the greatest risks to aquatic organisms while measured concentrations of other metals were less than thresholds for adverse effects. Approximately 99.9% and 50.7% of the aquatic organisms were predicted to be affected by Cu and Zn in surface water of Tai Lake respectively. Our results highlight ecological risks of Cu and Zn in water of a typical, large, urban lake in Eastern China, which was ignored in the past.

Assessment of Heavy Metal Pollution in Topsoil around Beijing Metropolis.

The topsoil around Beijing metropolis, China, is experiencing impacts of rapid urbanization, intensive farming, and extensive industrial emissions. We analyzed the concentrations of Cu, Ni, Pb, Zn, Cd, and Cr from 87 topsoil samples in the pre-rainy season and 115 samples in the post-rainy season. These samples were attributed to nine land use types: forest, grass, shrub, orchard, wheat, cotton, spring maize, summer maize, and mixed farmland. The pollution index (PI) of heavy metals was calculated from the measured and background concentrations. The ecological risk index (RI) was assessed based on the PI values and toxic-response parameters. The results showed that the mean PI values of Pb, Cr, and Cd were > 1 while those of Cu, Ni, and Zn were < 1. All the samples had low ecological risk for Cu, Ni, Pb, Zn, and Cr while only 15.35% of samples had low ecological risk for Cd. Atmospheric transport rather than land use factors best explained the seasonal variations in heavy metal concentrations and the impact of atmospheric transport on heavy metal concentrations varied according to the heavy metal types. The concentrations of Cu, Cd, and Cr decreased from the pre- to post-rainy season, while those of Ni, Pb, and Zn increased during this period. Future research should be focused on the underlying atmospheric processes that lead to these spatial and seasonal variations in heavy metals. The policymaking on environmental management should pay close attention to potential ecological risks of Cd as well as identifying the transport pathways of different heavy metals.

Distribution, fractionation, and contamination assessment of heavy metals in offshore surface sediments from western Xiamen Bay, China

Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, Sr, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non-residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 (very high) and sites S10, S11, and S14 (moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase (RSP). Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant.

Distribution, bioavailability, and potential ecological risk of Cu, Pb, and Zn in soil in a potential groundwater source area.

In this study, we examined three horizontal and vertical soil profiles along a sewage drainage ditch in order to determine the spatial distribution of Cu, Pb, and Zn in soils and to assess the bioavailability and potential ecological risks associated with these metals in a potential groundwater source area. Results showed that the concentrations of Cu, Pb, and Zn were approximately at background level, suggesting that human activities (industrial and agricultural pollution) had a negligible influence on these metals in soil, and that the concentrations reflected the natural background levels in the study area. Cu, Pb, and Zn concentrations were slightly higher in topsoil (0-20cm) than deeper in the soil profile. Using a modified BCR sequential extraction method to evaluate the mobility and bioavailability of metals showed that the potential bioavailability sequence of Cu, Pb, and Zn at three depths in the soil profile was in the order Cu ≈ Pb < Zn. The potential ecological risk from the metals was evaluated using risk assessment code, and the results suggest that Cu and Zn pose no or low risk, while there is a low or medium risk from Pb. Results from groundwater monitoring showed that the groundwater was not polluted by leaching from soil.

Source identification and potential ecological risk assessment of heavy metals in PM2.5 from Changsha

The probable sources and potential ecological risks of Cu, Zn, Cd and Pb in PM2.5 in Changsha were analyzed. The intelligent medium-flow total suspended particle sampler was used to collect the PM2.5 samples from Yuelu (YL), Kaifu (KF), and Yuhua (YH) districts of Changsha in March–April of 2013. The total concentration of heavy metals (HMs) in PM2.5 was used for source identification by correlation coefficients and principal component analysis (PCA). Otherwise the potential ecological risks indices (RIs) were calculated based on the bioavailable fractions of HMs which were obtained through BCR sequential extraction. Almost 50% of Cu, Cd and Pb in PM2.5 of all sites were accumulated in soluble and reducible fractions by speciation analysis. The correlation coefficients and PCA analysis showed that HMs in PM2.5 of Changsha in spring were mainly from vehicular emissions, fuel combustion, resuspension of dust and other pollution sources. The average potential ecological RIs of HMs in PM2.5 of Changsha were 6193.80 which suggests that HMs in PM2.5 was extremely serious. These results would be a good reference for health studies and formulation of environmental regulations.

Heavy Metal Pollution in the Surface Dust from E-Waste Disposal Place and its Ecological Risk Assessment

Six specific types of surface dusts were collected from different e-waste disposal areas in Shanghai, China for the determination of toxic metals including Zn, Pb, Ni, Cd, Cr and Cu. These samples were obtained from interior of home appliance, second-hand household appliance maintaining store, open manual dissembling yard, enclosed electronic waste warehouse, enclosed dissembling workshop, as well as outside yard of plant. ICP-AES analyzing results revealed that metal concentrations in dust from home appliance interior and second-hand household appliance maintaining store were obviously higher than the soil background values. And the metal concentrations of dusts from open manual dissembling yard were similar to enclosed electronic waste warehouse. The concentrations of Pb, Zn and Cu in dust from enclosed dissembling workshop were about 3646.10, 3485.23 and 4049.70 mg/kg, which were respectively 9, 19 and 45 times higher than outside yard of plant. The potential ecological risks of metal pollution in these dusts were analyzed by estimating the distribution characterization of samples and the heavy metals. The results showed that potential ecological risk of Cu was the highest, and then was the Cd, Cr was the least. The ecological risk indexes of metals in dusts from enclosed dissembling workshop, home appliance interior and second-hand household appliance maintained store were considered to be significantly healthy harm, while those from open manual dissembling yard and enclosed electronic waste warehouse were relatively less harm.