background values
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Water ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 51
Author(s):  
Jianbo Liao ◽  
Xinyue Cui ◽  
Hai Feng ◽  
Shangkun Yan

The distribution and assessment of heavy metal pollution in sediments have been extensively studied worldwide. Risk assessment methods based on total content, background values, and sediment quality guidelines are widely applied but have never been compared. We systematically sorted out these evaluation methods, obtained evaluation results using actual monitoring data, and compared their applicability. The results showed that the background values of different metals are significantly different, which may depend on their mobility. Geoaccumulation index (Igeo) and enrichment factor (EF) values invariably decreased with the increase of background values for individual heavy metal enrichment risk assessment. Compared with EF, Igeo also showed a significant positive linear correlation with heavy metal content. Pollution load index (PLI), modified contamination degree (mCd), and potential ecological risk index (RI) showed significant differences in response to background values and evaluation levels for the comprehensive risk of heavy metal enrichment, but their distribution trends along with the sampling points were basically identical. Toxic risk index (TRI), mean ERM quotient (mERMQ), and contamination severity index (CSI) were used to evaluate the damage degree of complex heavy metals to aquatic organisms and shared a similar whole-process distribution trend. The modified hazard quotient (mHQ), which is used to evaluate the toxicity of a single heavy metal to aquatic organisms, showed a significant positive linear correlation with the total content of each heavy metal, indicating that the toxic effect on organisms can be predicted through the direct monitoring. The results of this study have important guiding significance for the selection of evaluation methods for heavy metal pollution in sediments.


2021 ◽  
Author(s):  
Ehab A. Ibrahim ◽  
El-Metwally M. Selim

Abstract The accumulation of trace metals in vegetable field soils is of expanding worry because of the potential health hazards and its detrimental effects on soil ecosystems. To investigate the state of trace metal pollution in vegetable field soils, 60 surface soil samples were collected from vegetable fields across the Eastern Nile Delta region, Egypt. The results explained that the concentrations of Cu, Mn and Ni were lesser than their corresponding background values, while the concentrations of Cd, Co, Pb and Zn were exceed their background values. The pollution indices showed that the study soil experienced low to moderate contamination, and the Cd and Cr contamination was serious. The hazard index values of nine trace metals signified that there no adverse non-carcinogenic risk for adults and children. The carcinogenic risk of Cd, Co, Ni and Pb for both age groups was within the acceptable limits, while Cr had critical carcinogenic hazard to children. Overall, the quality of studied soils is relative safety, although some samples impose serious pollution problems by Cd and Cr. Thus, properly monitor trace metals and soil management action should be applied to reduce further soil pollution in vegetable fields in the Eastern Nile Delta.


2021 ◽  
pp. 451-471
Author(s):  
Vesna V. Mrvić ◽  
Elmira Saljnikov ◽  
Biljana Sikirić ◽  
Darko Jaramaz

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1442
Author(s):  
Yousef Nazzal ◽  
Nadine Bou Orm ◽  
Alina Barbulescu ◽  
Fares Howari ◽  
Manish Sharma ◽  
...  

Dust is a significant pollution source in the United Arab Emirates (UAE) that impacts population health. Therefore, the present study aims to determine the concentration of heavy metals (Cd, Pb, Cr, Cu, Ni, and Zn) in the air in the Sharjah and Ajman emirates’ urban areas and assesses the health risk. Three indicators were used for this purpose: the average daily dose (ADD), the hazard quotient (HQ), and the health index (HI). Data were collected during the period April–August 2020. Moreover, the observation sites were clustered based on the pollutants’ concentration, given that the greater the heavy metal concentration is, the greater is the risk for the population health. The most abundant heavy metal found in the atmosphere was Zn, with a mean concentration of 160.30 mg/kg, the concentrations of other metals being in the following order: Ni > Cr > Cu > Pb > Cd. The mean concentrations of Cd, Pb, and Cr were within the range of background values, while those of Cu, Ni, and Zn were higher than the background values, indicating anthropogenic pollution. For adults, the mean ADD values of heavy metals decreased from Zn to Cd (Zn > Ni > Cr > Cu > Pb > Cd). The HQ (HI) suggested an acceptable (negligible) level of non-carcinogenic harmful health risk to residents’ health. The sites were grouped in three clusters, one of them containing a single location, where the highest concentrations of heavy metals were found.


2021 ◽  
Vol 43 (4) ◽  
pp. 461-471
Author(s):  
Valentin Oreshkin ◽  
Vladislav Khrisanov

The article presents new analytical data on the content of cadmium and lead in river water obtained by the authors using highly sensitive specialized methods of analytical spectrometry. For the first time, a more than thirty-year (1983-2018) study has been carried out, tracing the concentration of elements in the mid-stream water of the Oka River in the area of Prioksko-Terrasny Biosphere Reserve (PTBZ) - a location remote from the zone of formation of technogenic dispersion flow. The general trend was found to be characterized by a gradual decrease in metal content, correlating with the implementation of various environmental measures in the river basin. The trend of decreasing concentration is well expressed for cadmium from 1983 to 1991 and is weaker from 1992 to 2018. Estimates are made of the average regional anthropogenic-dependent concentrations of elements in the Oka River waters, exceeding the Clark (background) values for the world’s rivers significantly. It can be predicted that, if this trend persists, cadmium concentrations in the water of a large plain river will approach the background values for surface waters of the Russian plain.


2021 ◽  
Author(s):  
Bernhard Wagner ◽  
Anneke Tammen ◽  
Dietmar Jung

Abstract Typical element background concentrations of rock units in Bavaria were evaluated by statistical means and presented in a lithogeochemical map, derived from the geological map at a scale of 1:25,000. The elements include 39 geogenic main and trace elements (SiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O, TiO2, P2O5 Li, Be, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, Tl, Pb, Bi , Th and U). The distributions of element concentrations in the lithogeochemical units follow closely lognormal patterns in a large majority of cases. Statistical parameters (10th, 25th, 50th, 75th, 90th percentiles) of investigated elements were determined using the cenfit function of the NADA package within the open source program R. The investigation, based on 8,838 analysed samples, provided data for about 2/3 of the area of Bavaria. The lithogeochemical map with medians (50th percentiles) and background values (90th percentiles) of the investigated elements is available in a web map application. Thus, the regional geogenic background values of the investigated elements in Bavaria are publicly available for a large variety of applications.


2021 ◽  
pp. 1816-1828
Author(s):  
Athraa B. Radhi ◽  
Sufyan M. Shartooh ◽  
Emad A. Al-Heety

The aim of this study is to determine the level of pollution with heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) and their potential sources in dust samples collected from schools in Ramadi City, Iraq. The dust samples were collected from 40 primary schools and two kindergartens and analyzed by using atomic absorption spectrophotometer. The heavy metal concentrations were found to follow the order Cr > Cu > Pb > Ni > Zn > Cd.  The results indicated that the concentrations of Cd, Cu, and Pb exceeded the permitted background values. The pollution level was assessed using the geo-accumulation index (Igeo) and pollution load index (PLI). The classification of dust samples according to Igeo values showed that they ranged from unpolluted for Cu, Cr, Ni, and Zn, to moderately polluted for Pb, and heavily polluted for Cd. The PLI values indicated no to moderate pollution load. The results of the comparisons of heavy metal concentrations with the background values, as well as the multivariate statistical analysis, indicated three groups of heavy metals with different sources or origins: (1) Cd and Cu (anthropogenic source: vehicle emissions); (2) Pb (mixed source); and (3) Cr, Ni, and Zn (Geogenic source). This study is the first attempt in Iraq to investigate the concentrations of heavy metals in the dust of indoor environments. This study provides the environmental protection managers and decision-makers with important information about the concentrations of heavy metals and their sources in indoor environments.


2021 ◽  
Vol 26 (2) ◽  
pp. 3-13
Author(s):  
E. A. Krasavtseva ◽  
◽  
S. S. Sandimirov ◽  

Introduction. This extended study is the first to analyze the chemical composition of the surface waters and bottom sediments of the lakes affected to various extents by Lovozersky Mining and Processing Plant (Revda urban settlement, Murmansk Region) performing mining and processing of rare metal ores. Methods. During the study, we used data obtained in the course of research in 1995–2005 and 2019–2020. Water and bottom sediment samples were analyzed using various methods. The total contents of elements in the bottom sediments were compared with the background values or, in their absence, with the clarke contents of elements in the Earth’s crust. To assess the level of pollution in the Sergevan River receiving wastewater from the plant, the maximum pollution index was calculated. Results. Over the past 35 years, the chemical composition of the surface waters of nearby water bodies underwent minor changes. No significant excess of maximum permissible concentrations for fishery water bodies was found. The comparison of the contents of heavy metals in the bottom sediments collected from Lakes Ilma and Krivoye with the background values revealed contamination of the Lake Ilma with strontium, zinc and manganese. Besides, a multiple excess of the content of rare earth elements (La, Ce, Pr, Nd), Nb and Ta was established in the bottom sediments of Lake Ilma in comparison with that in Lake Krivoye. The analysis of the river water samples taken at different distances upstream and downstream the site of wastewater discharge confirmed the assumption about the pollution of the Sergevan River by wastewater from the plant. Conclusion. The pollution of the water bodies is mainly caused by wastewater discharged from the plant, however, the increased content of rare earth elements in the bottom sediments of Lake Ilma may be due to air transport of particles of loparite ore concentration tailings, drainage from tailing dams, or degradation of underlying rocks.


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