Average Metal Concentrations Research Articles

Ecological risk assessment of metals in the Arctic environment with emphasis on Kongsfjorden Fjord and freshwater lakes of Ny-Ålesund, Svalbard

The concentrations of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in the sediments, water, phytoplankton, zooplankton, and macroalgae from Kongsfjorden Fjord and the freshwater lakes of Ny-Ålesund in the Svalbard archipelago were determined in order to describe the anthropogenic impacts related to the Ny-Ålesund town. Water samples from nine stations, sediment samples from 23 stations, plankton samples from five stations, and six species of macroalgae were collected and subjected to heavy metal analysis using atomic absorption spectrophotometry (AAS). Only Cu and Zn were detected in the water samples. The plankton samples had only Zn, Cu, and Cr. The average metal concentrations in macroalgae fell in the decreasing order of Cu > Zn > Cr > Cd > Pb. In sediment samples, the metal order was as follows: Zn > Cu > Cr > Pb > Cd. Multivariate statistical analyses including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to identify the source of the metal contamination. The metals were found to originate from a blend of both anthropogenic and geogenic sources. Pollution monitoring indices including geoaccumulation index (Igeo), contamination factor, contamination degree (Cdeg), pollution load index (PLI), and potential ecological risk (PER) were calculated using the metal data. In the study area, Igeo values of the metals showed pollution grades from 0 (uncontaminated) to 6 (extremely contaminated). Cdeg fell in classes from 1 (low contamination) to 4 (very high contamination). PLI values ranged between 0 and 5.68. PER values expressed that except for a few stations located at higher elevations in the glacial outwash plains, all other sites were highly polluted. The high level of pollution indices in the sites can be attributed to the anthropogenic activities persistent in the study area.

Analyss of Heavy Metal Content of Copper (Cu) in Cork Fish From Rawa Taliwang Lake, West Sumbawa Regency 2021

Rawa Taliwang Lake is the largest freshwater fish source in West Sumbawa Regency. Channa striata is a fish that is in great demand because of its health benefits. Fish are organisms that are used as bioindicators of heavy metals in waters. This study aims to determine the metal content of Copper (Cu) in Channa striata from Rawa Taliwang Lake and to find out Channa striata from Rawa Taliwang Lake is still suitable for consumption according to the copper metal contamination threshold in food. This research was conducted at Lake Rawa Taliwang in September-November 2021. Data collection was carried out by purposive sampling method at 2 research stations, namely the East side and the West side. The sample in this study were 4 Channa striata caught with fish traps. The samples were then analyzed for the content of copper (Cu) which was carried out at the BLKPK NTB Province using Atomic Absorption Spectrophotometry (AAS). The body part of the fish that is meticulous is the flesh of the fish that has been cleaned of scales and removed from the internal organs. The test results showed that the average metal content of copper (Cu) in Channa striata from Lake Rawa Taliwang was around 0.697 mg/kg (ppm). The content of copper metal (Cu) in Channa striata from Lake Rawa Taliwang is still below the maximum threshold for metal contamination in food in accordance with the Regulation of the Directorate General of Drug and Food Control Number: 03725/B/SK/VII/89 concerning the maximum threshold for metal contamination, namely 20.0 mg/kg.

Heavy metal pollution in agricultural soils of a typical volcanic area: Risk assessment and source appointment.

Heavy metals are naturally occurring elements with high natural background levels in the volcanic area. Therefore, it is necessary to conduct a risk assessment and identify potential sources of heavy metals. In this study, 4488 soil samples (0-20cm) were collected in Chengmai County, a typical volcanic area in Hainan Province, and analyzed for eight heavy metals and major oxides. Pollution level, ecological risks, and health risks were evaluated by geo-accumulation index (Igeo), pollution index (PI), potential ecological risk index (RI), hazard index (HI), and carcinogenic risks (CR). The positive matrix factorization (PMF) model was further used to determine the priority source of heavy metals. The average values of heavy metal concentrations in soil were 7.06, 0.07, 156.88, 33.43, 0.05, 72.47, 19.48, and 67.51mgkg-1 for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, respectively. Except for Pb, the average concentrations of all heavy metals exceeded background concentration in Hainan soils, indicating different degrees of heavy metal enrichment. The Igeo and PI showed that the main pollutant element in volcanic soils was Ni, followed by Cr and Cu. The RI shows that the percentage of soil samples with considerable or worse potential ecological risk was 44.4% of the total samples, with Hg, As, Cd, and Ni causing high ecological risks. The estimated average daily doses of heavy metals were below the tolerable limits and the HI values were below one for both adults and children, indicating that the residents had an acceptable potential non-carcinogenic risk. However, the potential carcinogenic risk of exposure to Cr, Ni, and As was unacceptable for residents, with high CR values exceeding 10-4, especially for children. Based on the PMF, five major sources of heavy metals were found in the study area: Ni, Cu, and Zn mainly from parent materials, As and Pb from daily life and vehicle emissions, Cd from agricultural activities, Hg from industrial activities, and Cr from parent materials under different environmental conditions. Significant positive correlations between Al2O3, TFe2O3, Mn, soil organic carbon (SOC), and heavy metals reflect that aluminium-rich minerals, Fe-Mn oxides, and SOC are the most critical factors affecting heavy metal accumulation in volcanic agricultural soils.

Bioaccumulation of Heavy Metals in Polymesoda erosa in the Batanghari River, Jambi Province

The water quality of the Batanghari River in Jambi Province has been categorized as polluted because it contains heavy metal contents, such as Pb, Mn, Cd, and Hg. One of the river biotas that become local people’s favorite and can accumulate heavy metals is Polymesoda erosa mussels. This research aimed to investigate and analyze the heavy metals contained in mussels in the Batanghari by using AAS and ICP methods. The results showed that the average content of lead metals (Pb) in Polymesoda erosa in Point A was 5.93 mg/kg while in Point B was 13.5 mg/kg. Mussels with such contents of Pb metal are not safe to consume because the contents exceed the threshold of SNI 7387:2009 with a maximum limit of Pb at 1.5 mg/kg. Meanwhile, the average content of manganese metal (Mn) in Polymesoda erosa in Point A was 89.24 mg/kg, while in Point B was 169.85 mg/kg. These numbers also exceed the standard threshold of manganese metal quality for fish by 20 mg/kg based on the Turkish Guideline. The average concentration of Cd metals and Hg metals in Polymesoda erosa in Point A was 0.04 mg/kg and 0.122 mg/kg, respectively; while in Point B was 0.05 mg/kg and 0.169 mg/kg, respectively. The concentrations of Cd and Hg metals do not exceed the threshold and are safe to consume. However, since Pb and Mn metals have exceeded the threshold and are not safe to consume, the Polymesoda erosa mussels in the Batanghari are still not safe to consume.

Spatial distribution characteristics and evaluation of soil pollution in coal mine areas in Loess Plateau of northern Shaanxi

The ecological environment in Loess Plateau of Northern Shaanxi is fragile, so the soil pollution caused by the exploitation of coal resources cannot be ignored. With Shigetai Coal Mine in Loess Plateau of Northern Shaanxi as the object of study for field survey and sampling, the content of heavy metals in soil is analyzed, the environmental pollution in the research area is evaluated by the single factor pollution index method, comprehensive pollution index method and potential ecological risk index method, and the spatial distribution characteristics of heavy metals are discussed by the geostatistics method. According to the study results, the average contents of heavy metals Hg, Cd, Pb and Cr are 2.03, 1.36, 1.11 and 1.23 times of the soil background values in Shaanxi Province respectively and the average contents of other heavy metals are lower than the soil background values in Shaanxi Province; Hg and Cd show moderate variation while As, Pb, Cr, Zn, Ni and Cu show strong variation; the skewness coefficients and kurtosis coefficient of Cd, As and Cu in the soil within the research area are relatively high, and these elements are accumulated in large amounts. Single factor pollution index (Pi) and potential ecological risk index (E) indicate that heavy metal Hg is the main pollution factor and mainly distributed in the east and north of the research area. The comprehensive index of potential ecological risk (RI) of the research area is 1336.49, showing an extremely high ecological risk, and the distribution characteristics of potential ecological risk are consistent with that of potential ecological risk index (E) of Hg. The results of ecological risk warning show that Hg is in a slight warning status, while Cd, Pb and Cr are in a warning status. The areas with high ecological risk warning values are mainly distributed in the east and north, and the whole research area shows relatively obvious zonal distribution law. The soil is disturbed greatly during the coal mining, so the ecological governance of the mine area shall adapt to the local natural conditions and regional environmental characteristics and follow the principle of “adjusting governance measures based on specific local conditions and classifications”. An environmentally sustainable governance manner shall be adopted to realize the protection of the ecological environment and high-quality development of coal resources.

Distribution and ecological health risk assessment of dissolved trace metals in surface and bottom seawater of Yantai offshore, China

The biogeochemical cycle of trace metals plays an important role in the coastal zone. The distribution, interaction, and biogeochemical behavior of dissolved trace metals in surface and bottom seawater are still unclear. This study analyzed the distribution and performed an ecological health risk assessment of dissolved trace metals (Zn, Cd, Co, Pb and Cr) in surface and bottom seawater in the summer (August) of 2019 and 2020 in the seawater of the Yantai offshore area, China. Zinc (Zn), cadmium (Cd), cobalt (Co), lead (Pb) and chromium (Cr) ranged from 23.76–117.47 μg/L (42.67 μg/L ± 15.15), 0.21–0.51 μg/L (0.30 μg/L ± 0.05), 0.90–2.94 μg/L (1.09 μg/L ± 0.31), 0.13–1.06 μg/L (0.39 μg/L ± 0.17), and 2.00–9.9 μg/L (5.38 μg/L ± 2.99) in the summer of the two years. The average metal (Zn and Co) concentrations were slightly higher than the other Chinese coastal areas, while the major contamination pressures were from Zn and Pb. The largest contaminants were in the following order: Zn > Pb > Cd > Cr > Co. Correlation analysis, principal component analysis and hierarchical cluster were used to determine the potential origins and cause the spatial distribution of the multiple dissolved trace metals. The major sources of the trace metal contamination in study area were identified as external inputs from natural human and atmospheric settling and the natural release of the trace metals in sediments under external disturbances. Riverine inputs, the Lubei coastal current and aquaculture significantly influenced the multi-parameter horizontal distributions of the dissolved trace metals and dissolved organic carbon. Although the growth of phytoplankton was strong in summer, the uptake of Zn, Cd, Co and Pb was negligible compared with the exogenous input. The concentrations of Zn, Cd, Co and Pb were higher in the surface than those in the bottom. Monsoons, tides and wind waves also influence the migration, transformation and distribution of dissolved trace metals and dissolved organic carbon. This study provides important information on the biogeochemical cycle process (migration and conversion) and distribution of dissolved trace metals at different depths in coastal and marine pasture areas.

Evaluating groundwater pollution with emphasizing heavy metal hotspots in an urbanized alluvium watershed of Yamuna River, northern India

For the management and prevention of groundwater pollution in the basin, a comprehensive evaluation of groundwater contamination hazards is required. The anthropogenic activities play a vital role in groundwater pollution of the alluvium watershed of Yamuna River in Mathura district through the infiltration process. In this study, several groundwater pollution indices such as pollution index of groundwater (PIG), heavy metal pollution index (HPI), ecological risk index (ERI) and multivariate approach i.e., Principal component analysis (PCA) have been used to detect the contaminated hotspots of the study area. During the study, 110 groundwater samples were collected from shallow hand-pumps to assess the groundwater quality based on selective major ions mainly Chloride, Sulphate, Nitrate, and Fluoride and heavy metals such as Zinc, Lead, Nickel, Cadmium, Iron, Chromium, Manganese and Copper respectively. The results show that the average heavy metal concentrations follow the trend of Ni (2.92 mg/L) > Pb (2.06 mg/L) > Fe (1.73 mg/L) > Zn (0.76 mg/L) > Cr (0.66 mg/L) > Cd (0.45 mg/L) > Mn (0.40 mg/L) > Cu (0.02 mg/L) respectively. Likewise, ERI results indicate a high potential ecological risk in the study area. Based on this, we classify the groundwater samples into good (9.10 %), poor (13.6 %), and very poor quality (77.3 %). The hotspots are found in the Northwestern region of the study area. The findings indicate that the escalation of municipal waste, industrial waste, agriculture applications and practices in the alluvium watershed of Yamuna River, directly and indirectly, affects the groundwater aquifers. This elaborate study helps in designing an appropriate mitigation strategy for pollution containment as well as proper water resources management.

Temporal distribution, accumulation, speciation and ecological risk of heavy metals in the sediment of an urban Lagoon catchment at Xiamen in China

ABSTRACT The present study investigated the temporal distribution, accumulation, speciation and potential ecological risk of heavy metals in the sediment of an urban Yundang Lagoon catchment (YLC) at Xiamen in China. Total heavy metals concentration of Cr, Mn, Ni, Cu, Zn, As, Cd and Pb showed a significant seasonal variation in the sediment. Therefore, the average total metals concentration of Cr, Mn, Ni, Cu, Zn, As, Cd and Pb was 61.95, 529.95, 28.03, 64.95, 351.22, 10.29, 1.38 and 56.30 mg/kg for spring; 66.78, 501.22, 30.55, 67.72, 326.42, 10.91, 0.89 and 58.12 mg/kg for summer; 64.87, 472.80, 24.09, 66.26, 323.40, 5.51, 0.64 and 58.68 mg/kg for autumn; 82.36, 1589.05, 27.27, 82.64, 369.31, 11.79, 0.60 and 562.24 mg/kg for winter, respectively. Temporal metals speciation indicates a considerable seasonal variation of metal fraction concentrations. Igeo values have indicated considerable seasonal variation of pollution sources in the sediment of YLC. The temporal pollution load index indicates that winter sediment has the highest pollution load than other seasons.

Concentrations of Heavy Metals in Three Brown Seaweed (Phaeophyta: Phaeophyceae) Collected from Tourism Area in Sanur Beach, Coast of Denpasar, Bali and Public Health Risk Assessment

Highlight Research Brown seaweed heavy metals content varies between species Risk assessment showed low health risk for heavy metal from intake of the three brown seaweed The three types of brown seaweed did not show carcinogenic properties to metal Arsenic (As) Abstract Marine brown seaweed are known as one of the potential biological agents to be developed as functional food and medicinal sectors. This study aims to examine the concentration of heavy metals (Pb, Cd, Hg, and As) in brown algae (Sargassum aquifolium, Padina australis, and Turbinaria ornata.) and the possible exposure to health risks caused by consumption. Heavy metal concentrations were determined using Atomic Absorption Spectroscopy (AAS) on brown seaweed samples obtained from three different sites. The average concentration of heavy metals in the dry weight of brown seaweed remains within the guidelines established by The Food and Drug Supervisory Agency (BPOM) Number 32 of 2019 concerning the Safety and Quality of Traditional Medicines, which is then used to calculate the estimated daily intake (EDI), target hazard quotient (THQ and TTHQ), and target cancer risk (TCR) for arsenic associated with food exposure to potentially toxic metallic elements. Each species of brown seaweed has a THQ and TTHQ level of <1, indicating that one or more toxic metal elements in the same meal provide no significant non-carcinogenic risk. The TCR for arsenic in these seaweeds are all less than 1 x 10-4, indicating no cancer risk. There are no chronic health hazards related with the ingestion of brown seaweed harvested from the coast of Sanur Beach at Denpasar, Bali.

Analysis of Heavy Metals in Water and Sediment in Singkep Island Coastal Waters

Analysis of the content of heavy metals Cu, Pb and Zn in seawater, sediment and snails (C. obtusa) in Singkep island was held on June – July 2022. All parameters measured water quality is still within tolerable limits for the survival of the aquatic organism . Samples of sea water, sediment and snails (C. obtusa) were taken from five stations with three replicates at each station. Heavy metals were analyzed in the KLH Pekanbaru laboratory using an Atomic Abortion AA-7000 Shimadzu spectrophotometer. The results showed that the average content of heavy metals in Singkep waters was 0.0724 mg/l (Cu), 0.1285 mg/l (Pb)) and 0.11525 mg/l (Zn), the sediment was 10.7513 ug/g (Cu ), 25.7750 ug/g (Pb) and 34.1493 mg/g (Zn). Simple linear regression analysis indicates negative correlation between metals content in seawater and in sediment with Y = 12.864 –29.178X, r = 0.1616 (Cu), Y = 26.181 – 3.1564X, r = 0.0632(Pb) ; and Y=45.479 - 61.286X, r = 0.2689 (Zn).

Application of Different Indices for Soil Heavy Metal Pollution Risk Assessment Comparison and Uncertainty: A Case Study of a Copper Mine Tailing Site

The concentrations of Cu, Zn, As, Pb, Cr, and Cd in soil were analyzed in a mining area in the Inner Mongolia Autonomous Region, China. The average metal concentrations in the soil samples were 204.07 mg/kg, 88.15 mg/kg, 14.47 mg/kg 88.52 mg/kg, 56.45 mg/kg, and 0.235 mg/kg, respectively. Based on the evaluation standards, background values of the soil heavy metals, multiple soil pollution assessment indices, such as the single factor index (Pi), the geological accumulation index (Igeo), the Nemerow index (Pn), the ecological risk index (ER), and the health risk index (HI) were applied to evaluate the soil environmental risks in the study area. It was found that in different soil layer depths (0–10 cm, 10–30 cm, and 30–50 cm), the evaluation result of each index showed that there were significant spatial differences in soil pollution levels, and the focus of different indices differed greatly from each other. The Pi put 18.14% of the area at high risk of soil contamination levels, due to the fact that this index highlights the Cu pollution factor more than other indices and relatively amplifies hazards in some high-risk areas. While the Pn indicated that 61.36% of the study area was at a safe level of soil contamination, it can underestimate the regional soil heavy metal pollution risk. In order to scientifically carry out soil-pollution-risk prevention and control, it is necessary to comprehensively compare and analyze the information disclosed by different indices.

THE BACKGROUND CONCENTRATION OF SOME HEAVY METALS AT NYSC ORIENTATION CAMP LAYOUT, KATSINA

An anthropogenic activities leads to the presence of heavy metals in an environment which lead to environmental pollution. The area has become gradually engage with various waste such as animal waste, refused dump, spilling of petrol, kerosene, engine oil etc which can introduces the trace heavy metals. The research of background concentration of various heavy metals in soil samples taken from the NYSC orientation camp layout, which is situated in Katsina state, Nigeria, at latitudes of 643.7 m to 798.5 m and longitudes of 18 21I32IIE to 18 28I37II, was conducted. At intervals of 100 m, soil samples were taken from the locations, and each 100 m was divided into 10 m. (A1A10). In order to determine the concentration of the five examined heavy metals, a flame atomic absorption spectrophotometer (FAAS) was used (Co, Cr, Pb, Cd, Cu). The locations have an average heavy metal concentration of:- 0.16009, 0.55449, 0.02804, 0.00231, and 0.10406 ppm Respectively. Significant differences were observed by comparing the mean concentration of the heavy metals in the study areas with world health organization (W.H.O) threshold limit, national and international studies and it was suggested that the samples were not contaminated with the heavy metals. But the metals were detected and there is no need for immediate implementation and remediation measures by the relevant authority. It was and recommended that industries, factories and filling station should not be located at the area in order to minimize human activities so as to maintain stable environment free from pollutants

​​Levels of Metals and Nutritional Composition of Garden Cress (Lepidium sativum) Seed, in Southern Ethiopia

Background: Garden cress (Lepidium sativum) belongs to the Cruciferae family, a fast-growing edible herbaceous plant. This study aimed to determine the essential and non-essential metals levels and nutritional composition of garden cress seed grown in the Wolaita Zone in southern Ethiopia. The study was carried out by collecting garden cress cultivated in Jage, Wandara, Taba, Hilena, Siyara, Demba Gale, Himbecho, Afama and Gara sites of the Wolaita Zone, Southern Ethiopia. Methods: 27 triplicate garden cress seed samples were collected from nine selected sites and digested by the wet digestion method. The level of metals in the sample was determined by using FAAS. Result: The result showed that the average concentration of K, Ca, Mg, Fe, Cu and Zn in the garden cress seed samples in mg/100 g dry weight, were in the range of 1179.76 to 1226.79, 249.52 to 291.62, 314.84 to 341.44, 7.29 to 8.48, 3.72 to 5.44 and 5.80 to 6.68, respectively. The average concentration of non-essential lead metal was not detected in all sample sites. The proximate composition of the garden cress seed sample was in the range of 19.68% to 22.87% for protein, 8.30% to 10.27% for Crude fiber, 20.72% to 24.17% for fat, 3.44% to 4.63% for ash, 1.37% to 2.59% for moisture, 40.56% to 43.24% for carbohydrate and 332.96 to 344.19 Kcal/100 g for energy. The study confirmed that the garden cress seed was a good source of essential metals and an excellent source of protein, carbohydrate, fiber, energy and fat contents. The concentrations of metals in garden cress were permissible compared with recommended permissible limits of WHO/FAO as well as USDA.

Determining heavy metal pollution in sediments from the largest impounded lake in the eastern route of China's South-to-North Water Diversion Project: Ecological risks, sources, and implications for lake management

The eastern route of the South-to-North Water Diversion Project (ER-SNWDP) is a major human health project designed to alleviate the water scarcity in the Beijing-Tianjin-Hebei region in China. Impounded lake water security is directly related to the water diversion project effectiveness. At present, there is not a thorough understanding of the sediment heavy metals in Lake Hongze, the largest impounded lake of the ER-SNWDP. Consequently, this study reports a distribution analysis of Cu, Zn, Pb, Cr, Cd, As, Hg, and Ni in 101 sediment samples from Lake Hongze; we, utilized the enrichment factor, geoaccumulation index, and potential ecological risk index for the are to determine the ecological risk of heavy metals. The heavy metal source was examined with correlation analysis and principal component analysis–multiple linear regressions. The results showed that the average heavy metal content (Cu, Zn, Pb, Cr, Cd, As, Hg, Ni) were 0.03–1.57 times greater than the Jiangsu Province background values. Cd, As, and Hg were the main contributors to the Lake Hongze ecological risk. Spatially, the open water area was the most polluted among the four lake parts, and most of the flushing area had a low ecological risk. Chengzi bay and the western lake area have similar risk profiles, but are lower than the open water area risk. Source analysis showed that nonpoint-source agricultural pollution and industrial production were important pollution sources, while a considerable portion of the heavy metal content came from atmospheric deposition and natural sources. This study identified the main contamination areas and revealed the possible sources of each heavy metal; as such, this study can serve as a reference for the remediation and management of Lake Hongze to ensure the water safety of the ER-SNWDP.

Spatial distribution and ecological risk evaluation of toxic metals in the southern Black Sea coastal sediments

Spatial distribution and ecological risk levels of toxic metals (Cu, Pb, Zn, Ni, Co, As, Sr, V, and La) in sediments from the southern Black Sea coastal (Türkiye) were evaluated. The sediment samples were taken in April and May 2019 from thirty-one stations, from depths ranged between 16 and 65 m. The average metal concentrations (in dry weight) varied from 59.4 ± 4.8 to 102.5 ± 12.3 for Cu, 39.3 ± 4,1 to 46.1 ± 2.9 for Pb, 104.5 ± 4.7 to 126 ± 6.9 for Zn, 21.2 ± 1.8 to 24.9 ± 1.4 for Ni, 9.8 ± 0.4 to 16.6 ± 1.5 for As, 16.7 ± 0.5 to 18.2 ± 0.9 for Co, 68.2 ± 11.4 to 123.3 ± 13.5 for Sr, 82.7 ± 13.1 to 97.3 ± 4.3 for V, and 16.2 ± 1.8 to 23.6 ± 1.8 μg g−1 for La. Geoaccumulation index (IGEO), Sediment enrichment factor (SEF), and pollution load index (PLI) indicated that Cu and Pb are above the pollution limits. Thus, continuous pollution monitoring programs should be established. Moreover, measures should be implemented more effectively to prevent pollution.

Distribution characteristics and potential ecological risk assessment of heavy metals in soils around Shannan landfill site, Tibet.

At present, sanitary landfill is mainly used for domestic waste treatment in Shannan City, Tibet. However, there are few studies on heavy metals in the soil around the landfill in Shannan city. Therefore, the surrounding soil of Luqionggang landfill in Shannan City, Tibet Autonomous Region, is taken as the research object. In the study, the geo-accumulation index method, Nemerow comprehensive pollution index method and potential ecological risk index method are mainly used to evaluate the pollution and risk of heavy metals in the soil around the landfill site. The main results are as follows: The average pH value of the soil around the landfill site is 9.37, belonging to the strong alkaline range. The average values of heavy metals Hg and Ni in soil exceeded the background content, and the average contents of other heavy metals Cu, Pb, Zn, Cr, As and Cd did not exceed the background content. The average content of these eight heavy metals did not exceed the screening value of the national soil environmental quality standard. In the horizontal direction, the average content of heavy metal elements Cu, Cr, Cd, Hg and Ni is relatively high in the west. The average content of heavy metals As, Zn and Pb in the north, east and south is slightly higher than that in the west. And the farther away from the landfill, the less the soil is affected by heavy metals. The evaluation results of geo-accumulation index show that heavy metal Hg is the most affected. The average value of the comprehensive pollution index is 2.969, which is between 2 and 3, belonging to the moderate pollution level. And the west side of the landfill (downstream area) is greatly affected. The evaluation results of potential ecological hazard pollution index show that the potential risk index of single pollutants of heavy metals Cu, Pb, Zn, Cr, Ni, As and Cd belongs to low ecological hazard level, and the potential risk index of single pollutants of heavy metal Hg belongs to relatively heavy ecological hazard level. On the whole, the total potential risk coefficient belongs to medium pollution hazard degree. According to the correlation analysis, there is no significant correlation between heavy metal elements As and Hg and the other six heavy metal elements. In addition, the pollution source of heavy metal As may be mainly soil forming factors and the pollution source of Hg may be mainly human factors.

Assessment of Heavy Metal Uptake in Potatoes Cultivated in a Typical Karst Landform, Weining County, China.

The average content of heavy metals in Weining soil of karst landforms is generally higher than that of other agricultural regions. The aim of this study was to evaluate the heavy metal content in potatoes from Weining county and to analyze the correlation between the content of heavy metals in potatoes planted in the soil of karst landform and the soil’s environmental factors (soil heavy metals, soil pH, soil organic matter, altitude). Weining county (Guizhou province, China) is a typical karst landform, and has a potato production yield of 2.7 million tons. In this study, 56 soil and potato samples were collected from Weining county and the heavy metal content in the soils and potatoes was detected by inductively coupled plasma atomic mass spectrometry (ICP-MS). The content of Cr, Ni, and As in the soil was found to be higher, with almost half of the samples exceeding the maximum allowable levels. A total of 9 of the 56 samples tested had pollution load index values greater than 1.0, which indicates serious soil pollution. It was found that the ability of the potato to absorb heavy metals from the soil was very low, with the average bio-concentration factors of the metals Zn, Cu, Pb, Cr, Ni, and As being 0.087, 0.088, 0.0028, 0.0034, 0.0066, and less than 0.001, respectively. The content of the six heavy metals in the potatoes were all lower than the maximum permissible limit. The results show that a high As content in the soil could increase the content of Pb in potatoes, that a lower pH was beneficial to the bioaccumulation of Cr and Ni in potatoes, and that a high altitude is detrimental to the bioaccumulation of zinc and copper in potatoes. The HRI ranged between 1.12 × 10−2 and 5.92 × 10−2.

Assessment of heavy metals distribution and environmental risk parameters in bottom sediments of the Pechora River estuary (Arctic Ocean Basin)

The article is devoted to the study of the content of heavy metals in the bottom sediments of the estuary of the Pechora River, which is the largest river in the European Arctic of Russia. In addition to metals, the particle size distribution and physicochemical parameters of river sediments were analyzed, such as the content of carbonates, organics and ash components. Average concentrations of heavy metals in the sediments of the Pechora Delta sediment have been found to be significantly lower than terrestrial values. The assessment of pollution and toxicity of sediments in the Pechora delta, made using various parameters Igeo, Cf, Cd, EF and ERI, showed a low level of heavy metals in bottom sediments, coupled with a low level of environmental risk. Despite the fact that high concentrations of heavy metals of anthropogenic origin are continuously recorded in the water of the Pechora River, (almost throughout the entire length), there is no accumulation of pollutants in the sediments of the delta. Thus, the estuary of the Pechora River, unlike other large estuary systems, does not act as a filter or sediment trap, which contributes to the penetration of heavy metals deep into the Barents Sea and the widespread distribution of pollutants in the ecosystems of the Arctic.

Assessment of Metallic Contamination in Soils and Sediments in the Bétaré-Oya Gold Artisanal Mine District, East-Cameroon

Mining is an activity that involves the use of chemicals and results in unsustainable and dangerous conditions for the miners, their families, the community and the surrounding ecosystem. This study was done to assess metallic contamination of soils and sediments in the Bétaré-Oya gold artisanal mine district, East-Cameroon. A total of thirty (30) samples of exploited soils, control soils and sediments were taken from the mining sites of Lom, Mbal and Mali. The concentrations of heavy metals and metalloids (Fe, Sr, Cu, As, Pb and Zn) were determined by Inductive Plasma Ionisation Source Atomic Emission Spectrometry. The results show that in the sediments metals such as: As (1.82), Cu (24.22), Pb (18.04) and Zn (65.69) have average concentrations slightly higher than the UCC and Average Shale reference values. In the exploited soil As (1.93), Cu (16.86) and Zn (96.22) have average concentrations slightly higher than the UCC and Average Shale reference values.While in the cotrol soils only As (1.62) and Zn (59.72) shows an average concentration slightly above the UCC reference values. The average concentrations of the different heavy metals and metalloids were then used to calculate the intensity of contamination in soils and sediments. The results of this calculation indicate that the Enrichment Factor (EF) of As, Sr, Zn and Pb indicate an extremely high enrichment in these elements. The geo-accumulation Index (Igeo) (22.85-25), the Contamination (CF) (1.47), the low values of the ecological risk indices suggest a low potential ecological risk and Pollution load index (PLI) (0.67) indicates extreme contamination with these elements in the soils and sediments. However, only As indicates a slight contamination (class 1) in soils and sediments. Gold panning activities and untreated mine tailings discharges would be considered as the main sources of sediment and soil pollution in Bétaré-Oya.

Optical property of dissolved organic matter and its correlation with heavy metals in surface water around metal mines to be exploited in southern Anhui Province, China

Abstract In this study, we aimed to clarify the optical characteristics of dissolved organic matter (DOM) in the surface water around the metal mine to be exploited and its relationship with heavy metals. In total 11 pond water samples and 21 river water samples were collected around the typical to be exploited metal mine in southern Anhui Province, China. The optical properties of DOM in surface water were studied using ultraviolet-visible (UV-Vis) spectroscopy and excitation-emission matrix (EEM) spectroscopy. Co-occurrence network analysis revealed the intrinsic relationship among UV-Vis spectral parameters, fluorescent components, and heavy metals. The results showed that the DOM in the river had higher content, but its molecular weight was smaller than in the pond. EEM coupled with parallel factor analysis (EEM-PARAFAC) revealed humic-like components (C1 and C2) and protein-like components (C3), and the average content of each fluorescent component in the river was higher than that in the pond. However, except for As, the average content of other heavy metals (Cr, Cu, Cd, Pb, and Zn) in ponds was more significant than in rivers. The co-occurrence network analysis result revealed that there might be different relationships between heavy metals and the DOM due to the various land use.