Moderate Pollution Levels Research Articles

Study on Diversity of Dragonfly (Odonata) as A Bioindicator of Water Quality in Mount Muria Area, Central Java

Water in the Mount Muria area is needed by the surrounding community to fulfill life. An indicator is needed to determine water quality. Dragonfly (Odonata) is one of the organisms as ecosystem controllers and bioindicators. This study aims to determine the diversity of dragonflies, determine water quality and describe the role of dragonflies as a bioindicator of water quality in the Mount Muria area. This type of research is descriptive quantitative research. The data collection technique used direct observation at 3 stations, namely the Colo Flower River, the Monthel Waterfall River and the River in the Rejenu Area. The results showed that there were 10 species of dragonflies consisting of 6 suborders Anisoptera and 4 suborders Zygoptera with the highest abundance value being Euphaea variegata (51.39%), Enallagma signatum (28.47%), Trithemis festiva (6.94%), Orthetrum glaucum (5.56%), Orthetrum chrysis (2.78%), Orthetrum pruinosum (2.08%), Orthetrum testaceum (0.69%), Orthetrum sabina (0.69%), Prodasineura autumnalis (0.69% ), and Drepanosticta fontinalis (0.69%). Based on water quality analysis and according to government regulation no. 82 of 2001, the water in the muria river belongs to category 2. According to the analysis of the family biotic index, it can be seen that the FBI value of the river in the Muria area is 5.60 which means the condition of the river is fair with moderate pollution levels. ©2019 JNSMR UIN Walisongo. All rights reserved.

Ecological Mapping in Assessing the Impact of Environmental Factors on the Aquatic Ecosystem of the Arys River Basin, South Kazakhstan

Assessment of the water quality of the Arys River basin based on the spatial distribution of richness of phytoperiphyton communities and abiotic variables was given for the first time. Altogether, 82 species were revealed in phytoperiphyton, including Bacillariophyta of 51, Cyanobacteria of 20, Chlorophyta of 7, and Charophyta of 4. Cluster analysis revealed the uniqueness of the composition of periphyton communities related to the abiotic conditions. The environmental preferences of the algae indicated fresh organic pollution in the lower reaches of the Arys River and weak or moderate levels of organic pollution in the rest of the basin. The ecological mapping of chemical data generally confirmed this conclusion. According to the maps, the highest water quality was revealed in the upper stream of the basin. The middle part of the river basin had the lowest water quality in terms of transparency, nitrite-nitrogen, and nitrate-nitrogen. The downstream of the Arys was characterized by a secondary deterioration in water quality according to the Aquatic Ecosystem State Index (WESI) index. We revealed the complicated interaction between natural and anthropogenic factors that caused changes in water quality in the Arys River basin.

Evaluation of Heavy Metals and Physicochemical Parameters of Oil-contaminated Soil and Water Samples from Bonny, South-South, Nigeria

This study analyzed physical, chemical and selected heavy metals concentration of oil-polluted soil and water samples from Bonny, South-South, Nigeria. Unpolluted soil and water samples were used as controls. The pH of the test soil sample was acidic (4.24±0.03) when compared with control (7.6±0.05). Chloride, Phosphorus, Magnesium and Potassium concentrations of the test soil samples were 1151.614±0.37 mg/g, 1.23±0.02 mg/g, 11.27±0.34 mg/g and 11.52±0.5 mg/g respectively. Selected heavy metals such as Iron (Fe), Cadmium (Cd), Mercury (Hg), Arsenic (As), Lead (Pb) and Copper (Cu) showed that Hg and As were below detectable limits in test and control samples while Cd and Pb were below detectable limit in the control sample while test sample had 0.015±0.01 mg/g and 1.73±0.04 mg/g respectively. Fe and Cu contents were high at 38.7±0.13 mg/g and 5.49±0.05 mg/g when compared with the control at 3.52±0.02 mg/g and 1.08±0.03 mg/g. Total Petroleum Hydrocarbon (TPH), Total Organic Carbon (TOC) and Total Organic Matter (TOM) were at 5.93±0.13 mg/g, 3.64±0.1 mg/g and 4.23±0.1 mg/g respectively. Water pH, Temperature, Conductance, Dissolved Oxygen, Biological Oxygen Demand (BOD5) and Turbidity were 5.21±0.03, 25.1±0.01ºC, 610±0.04 µS/cm, 5.0±0.03 mg/l, 1.8±0.02 mg/l, and 53.50±0.06 NTU respectively. Chloride, Phosphorus, Magnesium, Potassium, Calcium and Bicarbonate concentrations of the water were 609.82±0.37 mg/ml, 1.03±0.02 mg/ml, 13.41±0.42 mg/ml, 7.68±0.3 mg/ml, 21.22±0.12 mg/ml and 4.3±0.07 mg/ml in that order. Arsenic and Mercury were below detectable limit in both test and control samples while Fe, Cd, Pb, and Cu were 42.2±0.6 mg/ml, 0.016±0.001 mg/ml, 1.9±0.04 mg/ml and 5.2±0.03 mg/ml respectively. Total Petroleum Hydrocarbon, Total Suspended Solids, Total Dissolved Solids, and Total Solids were 3.87±0.11 mg/ml, 23036±0.51 mg/ml, 396.5±0.3 mg/ml and 23433±0.4 respectively. The levels of detected heavy metals were higher than the World Health Organization (WHO) permissible limits and Nigerian standard set by Federal Environmental Protection Agency (FEPA). This indicates a moderate level of pollution in both soil and water samples, as a result, poses a serious threat to ecological and species survivability as well as growth and reproduction of aquatic and plant life.

Distribution and Pollution Assessment of Nutrients and Heavy Metals in Surface Sediments from Shibalianwei Wetland in Hefei, Anhui Province, China

Shibalianwei is a large constructed wetland formed at the estuary of the Nanfei River adjoining Lake Chaohu. To investigate the distribution and pollution characteristics of nutrients and heavy metals in surface sediments of Shibalianwei Wetland, sediment samples were collected from 72 sites in July 2018. The source of the pollution was analyzed. Our results showed that the average contents of total nitrogen (TN), total phosphorus (TP), and organic matter (OM) in surface sediments of Shibalianwei were 2108.87 mg·kg-1, 1448.82 mg·kg-1, and 86.2 g·kg-1, respectively; in the external water system of the wetland, they were 2305.81 mg·kg-1, 1268.46 mg·kg-1, and 59.9 g·kg-1, respectively. The average contents of heavy metals of Mn, Cr, Cu, Pb, Cd, As, and Hg in Shibalianwei were 462.58, 42.12, 21.69, 18.05, 0.63, 5.67, and 0.059 mg·kg-1, respectively; in the external water bodies, they were 381.61, 36.85, 24.74, 30.70, 2.49, 6.47, and 0.035 mg·kg-1, respectively. In the assessments of nutrient pollution of internal water bodies of Shibalianwei, TN was at mild to moderate pollution levels, TP was at a heavy pollution level, and the comprehensive pollution index (FF) indicated that nutrients in Shibalianwei were at moderate to heavy pollution levels. The assessment results of the organic pollution index (OI) were consistent with the FF. The potential ecological risk assessments of heavy metals showed that both Cd and Hg reached certain ecological risks, which were indicated by RI and Eri. For external water bodies, the nutrient levels were also high and heavy metal pollution was relatively serious, indicating high ecological risks.

Assessment of short-term changes in street dust pollution with heavy metals in Lublin (E Poland)\u2014levels, sources and risks

Street dust forms as a result of the interaction of the atmosphere, lithosphere (pedosphere) and anthroposphere and can be regarded as an index of the condition of the environment in urban areas. At the end of the twentieth century, there was a significant decrease in heavy metal emissions in Europe, but not so intensive in Poland. The question arises: Is the intensity of pollution still decreasing? The study objective was to assess changes in street dust pollution with heavy metals in Lublin (E Poland) in the years 2013 and 2018. The sample collection sites (68) were located within streets with a varying intensity of motor traffic. Cd, Cr, Cu, Ni, Pb and Zn concentrations were determined in two dust fractions, 63–200 μm and < 63 μm, by means of an X-ray fluorescence spectrometer. The levels of street dust pollution with heavy metals, expressed both in absolute concentrations and geochemical indices, were lower in 2018 than those in 2013. The clearest decrease of concentration levels occurred within the main roads, in the 63–200 μm fraction for Cu and Cd, and in both fractions for Pb. The mean concentrations of the investigated metals, normalised to the background values, are in the following order for both fractions in 2013 and 2018: Zn > Cd > Cu > Cr > Pb > Ni. Metals form the following order for Igeo and EF: Zn > Cd > Cu > Pb > Cr > Ni. This order is slightly different for the ecological risk factor: Cd > Cu > Pb > Zn > Cr > Ni. In general, street dust in Lublin does not show contamination with Cr, Ni and Pb. Igeo and EF indices show moderate levels of pollution with Cu, Cd and Zn.

Characteristics of Heavy Metal Pollutants of PM2.5 from Open Burning of Municipal Solid Waste (MSW) and the Associated Exposure Health Risks

The characteristics and health risk assessment for heavy metal pollutants in PM2.5 discharged from the open burning of municipal solid waste (MSW) in different functional areas were studied using a flue gas diluted sampling system. The two common open burning modes of barrel and natural pile-up burning were considered. The results show that the concentration of zinc (Zn) was the highest among the heavy metals produced by five different components of waste incineration, ranging from 1324.03 to 3703.12 mg·kg-1. The concentration of cadmium (Cd) was the lowest, ranging from 20.25 to 63.68 mg·kg-1. According to the geo-accumulation index, lead (Pb), Zn, arsenic (As), and Cd were highly polluted in the measured MSW samples, and all four of these metals reached moderate or higher levels of pollution under natural pile-up burning methods. The geo-accumulation index of Cd was much higher than 5. The results of the human health risk assessment showed that non-carcinogenic risk values for 8 heavy metals (Pb, Zn, Cu, Mn, As, Cd, Cr, and Ni) by respiratory exposure were less than 1, which is within the safe range. For natural pile-up burning, the total non-carcinogenic risk values for As and Pb for children were higher than 1, indicating a non-carcinogenic risk. The carcinogenic risk values for four carcinogenic elements (As, Cd, Cr, and Ni) were less than 1.0×10-4, but still represented a low potential carcinogenic risk under exposure for long periods of time.

Distribution and Pollution Assessment of Nutrients in the Surface Sediments of a Macrophyte-Dominated Zone in Lake Taihu

To clarify the spatial distribution and pollution status of nutrients in the surface sediments from a macrophyte-dominated zone in Lake Taihu, total nitrogen (TN), total phosphorus (TP), alkali nitrogen (AN), available phosphorus (AP), and organic matter (OM) were measured at 60 sampling sites in Xukou Bay. A pollution evaluation and source apportionment analysis of these nutrients was also carried out. The average contents of TN, TP, AN, AP, and OM in the surface sediments of Xukou Bay were 1027.5, 423.2, 46.4, 15.3, and 17096.6 mg·kg-1, respectively, with the OM content being significantly higher in the northeast zone than in other areas of the bay. The average value of STN and STP was 1.75 and 0.91, respectively, indicating that TN and TP represent moderate and mild levels of pollution, respectively. The average comprehensive pollution index (FF) was 1.57, indicated that the surface sediment was moderately polluted. The observed organic pollution index indicated that the surface sediments in Xukou Bay were generally clean. Based on C/N values, organic matter in the surface sediments is derived from the bio-deposition of non-fibrous plants and phytoplankton. Based on correlation analysis, OM and TN in the surface sediments of Xukou Bay are derived from the same source, while TP is derived from an alternative source.

Assessment of heavy metals and arsenic pollution in surface sediments from rivers around a uranium mining area in East China.

Taking the surface sediments of rivers near a uranium mine in East China as the research object, the concentrations of seven metals, including Cr, Cu, Ni, Pb, Zn, Cd and As, were analyzed. The pollution degree and ecological risk of heavy metals and arsenic were evaluated according to the geo-accumulation index, pollution loading index, potential ecological risk index and sediment quality guidelines. Finally, the sources of pollution were determined by Pearson's correlation analysis, principal component analysis and hierarchical cluster analysis. The results indicated that Cr, Cu, Ni, Pb, Zn, Cd and As in sediments showed varying degrees of contamination, using the soil background value of the study area as a reference, and Cd was the main excessive pollutant in the sediments. In most parts of the river, Cd has reached a moderate level of pollution. The potential ecological hazards at sampling sites 9, 13, 17 and 18 are significantly higher than the other sites because of the impact of urbanization and uranium mining and smelting. Cu, Zn, Cr, Ni and Cd are mainly derived from urban activities and the uranium industry, Pb is mainly derived from vehicle emissions, and As is mainly derived from nature and rocks.

Co-effects of biofouling and inorganic matters increased the density of environmental microplastics in the sediments of Bohai Bay coast.

Size, shape and color are the basic parameters of environmental microplastic (MPs). However, the density of microplastics which is an important parameter to influence the fate of MPs in the environment has not been measured. Meanwhile, the MPs characteristics from coastal sediments of Bohai Bay remain unclear. In this study, the concentrations, distribution and composition (shapes and sizes) of MPs were investigated. The average concentration of MPs in the coastal sediments of Bohai Bay was 192.3±138.9items/kgdw, which was at a moderate pollution level. The MPs with fiber shape (54.5%), small size (52.0%) and low density (PE and PP) were dominant. In addition, flotation experiment showed that most of PE and PP had the higher density compared with seawater. Digestion experiments suggested that the density change of MPs was caused by the co-contribution of biofouling and inorganic minerals. The density increasing rates of PE and PP were 7.4%-12.6% and 12.1%-17.5%, respectively. Finally, we also estimated that the total number of MPs in the sediments of Bohai Sea was 534 trillion, which were significantly higher than that in global ocean surface, suggesting that the coastal sediments could be the sink of MPs.

Comprehensive Evaluation and Source Apportionment of Potential Toxic Elements in Soils and Sediments of Guishui River, Beijing

This study investigated the concentrations and spatial distributions, ecological risks, and potential pollution sources of potential toxic elements (PTEs) in the soils and sediments collected from the Guishui River (GSR) in Beijing, China. Multiple methods for pollution assessment and source identification of PTEs in the sediments/soils were used, including analysis of the physicochemical properties, Geo-accumulation index (Igeo), potential ecological risk index (RI), Pearson correlation, principal component analysis (PCA), and Pb isotopic ratio analysis. The results showed that PTE concentrations in the sediments/soils were similar to the soil background values (BV) of Beijing, except for Cd. Maximum Cd concentrations in soils were far below the guideline of the Environmental Quality Standard for Soils in China. PTE concentrations in the soils were slightly higher than those in the sediments. Upstream to downstream of GSR, PTEs concentrations in the soils and sediments remained stable. Pollution assessment based on Igeo and RI indicated that Cd was the main contaminant with moderate pollution levels. PCA results showed that Cd originated from anthropogenic sources, mainly including pesticide and fertilizer residues, while other metals mainly originated from natural sources. Further source identification using Pb isotopic ratios and PCA indicated that Cu, Pb, and Zn in GSR originated from anthropogenic sources (aerosols and coal combustion) and atmospheric deposition was considered as the primary input pathway.

Spatial distribution, contamination levels, sources, and potential health risk assessment of trace elements in street dusts of Urumqi city, NW China

A total of 83 dust samples were collected from the streets of Urumqi city in NW China and analyzed for the concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn elements. The spatial distribution, contamination levels, main sources, and potential health risks of these trace elements were determined based on geostatistical analysis, geo-accumulation index, multivariate analysis, and the health risk assessment model introduced by the USEPA, respectively. The obtained results indicate that the average concentrations of Cd, Cr, Cu, Hg, Ni, Pb, and Zn exceed the corresponding background values determined in Xinjiang soils by factors of 2.0, 1.35, 1.38, 8.24, 1.28, 2.09, and 3.26, respectively. The spatial distribution patterns of the nine trace elements in street dust were found to be substantially heterogeneous, and the contamination level decreased in the following order: Hg > Zn > Pb > Cd > Cr > Cu > As > Ni > Mn. Based on the identified concentrations, the collected dust samples were found to be moderately polluted by Hg, and not polluted by As, Cr, Cu, Mn, and Ni. The remaining elements, Cd, Pb, and Zn lie on the borderline between non-pollution and moderate pollution levels. Furthermore, it was shown that Mn and Zn in street dusts originate from both, natural and anthropogenic sources, while As, Cd, Cr, Cu, Hg, Ni, and Pb are mainly produced by anthropogenic sources. Overall, the carcinogenic and non-carcinogenic health risks of the analyzed elements, instigated primarily by oral ingestion of street dusts, were found to be within the acceptable range for both, children and adults. As and Cr are the main non-carcinogenic elements, whereas Cr is the major carcinogenic element among the investigated dust-bound metals in the study area.

Imperiling on Urban Environment by Air Pollution and its Impact on Human Health

Present study was carried out to analyze the concentration of the pollutants due to air born particulate matter (PM10) and infectious trace gases and their effects on human health at ten different locations along busy intersections in the commercial, residential and industrial areas of Karachi city. At each selected location, the study was carried out to determine the level of particulate matter and trace gases for a period of 8 h twice in a month during the year 2015. Samples were collected at ten selected locations i.e. Karimabad(C-1), Tibet Centre(C-2), and Liaquatabad(C-3) in commercial areas; PIB Colony(R-1), Nazimabad(R-2) and Gulshan-e-Iqbal(R-3) in residential areas; Siemens G. Belt(I-E1), Naurus G Belt (I-E2), Singer Chowrangi(I-W3) and Chamra Chowrangi(I-W4) in industrial areas of the city. Resultsreceived from different air quality categories were calculated according to National Environmental Quality Standard (NEQS) at selected locations, as in commercial areas showing poor pollution level for trace gases and PM10 due to high traffic density. In Residential areas PIB Colony (R-1) and Gulshan-e-Iqbal (R-3), found under good category with respect to the trace gases and moderate pollution level for the PM10 pollution, having low traffic density whereas Nazimabad(R-2) presents moderate category for trace gases and unhealthy category for PM10 pollution with high traffic density. In industrial areas Singer Chowrangi (I-W3) and Chamra Chowrangi(I-W4) found under moderate pollution level with moderate traffic density, whereas, Siemens G. Belt(I-E1) and Naurus G. Belt(I-E2) locations are represented by moderate pollution values for trace gases and found under poor pollution level for PM10 pollution, may be due to industrial emissions and heavy vehicular emission. Level of PM10 and trace gases at all the selected sites excluding residential areas, exceeds the permissible limits as specified by NEQS.

Ecological risk assessment and source apportionment of metals in the surface sediments of river systems in Lake Taihu Basin, China.

In this study, the concentrations of Zn, Cr, Ni, Cu, Pb, As, Cd, and Hg in the surface sediments of 94 sites sampled from six water systems in the Lake Taihu Basin in China were measured, and the pollution risks and sources of the metals were identified. The results showed that the mean concentrations of Zn, Cr, Ni, Cu, Pb, As, Cd, and Hg in the riverine surface sediments were 163.6, 102.5, 45.5, 44.7, 37.0, 13.3, 0.5, and 0.1mg/kg, respectively, higher than the corresponding background values (except for Hg). According to the geoaccumulation index (Igeo), the Pb, Ni, Zn, Cu, and Cd concentrations in the riverine surface sediments were generally at low levels of pollution. Based on a pollution load index (PLI) evaluation, the Pb, Ni, Zn, and Cu concentrations in the riverine surface sediments were generally at moderate levels of pollution. According to the thresholds of potential ecological risk, the Cd and Hg concentrations in the riverine surface sediments exhibited moderate potential ecological risks. Multivariate statistical analysis indicated that the Pb in the riverine surface sediments primarily originated from domestic sewage, agricultural wastewater discharge, and petroleum combustion; the concentrations of Cr, Ni, and Zn were influenced by the electroplating and alloy manufacturing industries; the concentrations of Cu and As mainly originated from pesticide use and industrial wastewater discharge; and those of Cd and Hg primarily stemmed from industrial wastewater discharge. This research provides information regarding metallic contamination and the possible associated ecological risks to benthic organisms in the surface sediments of river systems and is useful for developing sustainable strategies for environmental pollution control and management in the Lake Taihu Basin.

Pollution Assessment and Source Apportionment of Trace Metals in Urban Topsoil of Xi’an City in Northwest China

Sixty-two topsoil samples were collected within the third ring road of Xi'an City in Northwest China and analyzed by X-ray fluorescence spectrometry for the concentrations of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn. The pollution levels of trace metals were assessed by pollution index (PI) and Nemerow pollution index (NPI). Meanwhile, the sources of trace metals were apportioned by receptor models, including positive matrix factorization (PMF), UNMIX, and principal component analysis-multiple linear regression (PCA-MLR). The average concentrations of the trace metals analyzed in the urban soil exceeded the corresponding soil element background values of Shaanxi Province, especially for Co, which was 2.38 times higher than the corresponding background value. The mean of PI was 2.38 for Co, reflecting a moderate pollution level, and ranged from 1.07 to 1.72 for other trace metals, presenting slight pollution levels. The NPI of trace metals varied between 1.20 and 3.50 with an average of 2.00, indicating that trace metals presented slight pollution in 62.90% of soil samples, moderate pollution in 30.65% of soil samples, and heavy pollution in 6.45% of soil samples, respectively. Three sources of trace metals apportioned by the three receptor models were mixed nature and anthropogenic source, traffic exhaust, and industrial emissions. The contributions of them were 38.58%, 32.72%, and 28.70% from the PMF, 65.36%, 17.76%, and 16.88% through the UNMIX and 49.16%, 38.90%, and 11.94% via the PCA-MLR, respectively. Meanwhile, the study results suggested that the combined usage of multiple receptor models is a good method to apportion the source compositions and contributions of trace metals in urban soil.

Contamination and Health Risk Assessment of Heavy Metals in the Soil of Major Cities in Mongolia

Using the case of Ulaanbaatar, Erdenet, and Darkhan cities from Mongolia, the study aimed to assess the contamination level and health risk assessment of heavy metals (As, Cr, Pb, Ni, and Zn) in urban soil. A total of 78 samples was collected from a variety of functional areas. The geoaccumulation index (Igeo) and integrated pollution index (IPI) were used in pollution assessment, while the health risk was scored using a hazard quotient (HQ) and health index (HI) for non-carcinogenic heavy metals, as well as a lifetime average daily dose (LADD) for carcinogenic heavy metals. The results show that the concentration of heavy metals in the soil samples taken from Darkhan city, which presented “uncontaminated” values in terms of Igeo for all metals, was relatively lower than other cities within the contamination assessment. Furthermore, the Igeo value signified “uncontimated to heavily contaminated” soil in the Ulaanbaatar and Erdenet cities. Typically, as for the IPI that observed similar trends with Igeo, the mean IPI values in Ulaanbaatar, Erdenet, and Darkhan were 1.33 (moderate level of pollution), 1.83 (moderate level of pollution), and 0.94 (low level of pollution), respectively. In terms of the assessment of potential health risk, there was a particular or different level of ingestion, dermal contact, and inhalation exposure pathway for human health. Among these three different pathways, the ingestion was estimated by the main contributor for health risk. Each value of HQ and HI indicated that soil heavy metals of studied cities were at a safe level (<1) or had the absence of a significant health risk there. In addition, the potential health risk for children was greater than for adults, where heavy metal values of HI for children had a high value compared to adults. We estimated carcinogenic risks through the inhalation exposure, and as a result, there were no significant risks for human health in the studied cities from three elements (As, Cr, and Ni).

Concentration, Source, and Total Health Risks of Cadmium in Multiple Media in Densely Populated Areas, China.

Cadmium (Cd) is a non-essential and harmful element to humans. Cadmium contamination is a serious issue for human health, especially in densely populated agroecology areas. In this study, the investigation of an agroecology area was conducted to gain insight into the relationship between Cd in wheat and soil and then evaluate the Cd total risk for human health. The soil samples and their matching wheat samples, underground water samples, and atmospheric deposition (air) samples were collected from a wheat-growing area in an agroecology plain. The cadmium concentration in the four types of media, in order, was air > soil > wheat > water. The mean concentration of the geoaccumulation index (Igeo) showed that the total Cd in soil (Cd-T) and Cdair reached a mild and moderate pollution level. The results of the correlation and principal component analysis (PCA) showed that the majority of Cdwheat originated from Cd-2 (exchangeable), Cd-4 (humic acid-bound), and Cd-7 (residual). Furthermore, the results of the stepwise multiple linear regression (SMLR) showed that three fractions were primarily controlled by Cd-T: clay, cation exchange capacity (CeC), and total organic carbon (TOC). In addition, the total cancer risk (CR) of Cd in multiple media was, in the order wheat > water > soil > air. It is noteworthy that the Cd content in underground water and wheat by the ingestion pathway posed cancer risks to the local residents and provided a comprehensive insight into multiple media environment management. Furthermore, it provides a very significant basic study for detailed research into the mobility and transformation for factions.

Source analysis and risk assessment of heavy metals in development zones: a case study in Rizhao, China

The effects of heavy metal pollution in parks have caused widespread concern. This study investigated the concentrations and sources of eight heavy metals in the economic and technological development zone in Rizhao City. Geo-accumulation index ([Formula: see text]) and potential ecological risk index (PERI) were used to assess the pollution level of the development zone. Sources of heavy metals were analyzed through correlation analysis (CA) and principal component analysis (PCA). Descriptive statistics showed that many types of heavy metals accumulated in the development zone. The average concentrations of Pb, Cd, Hg, Ni, and Zn in the soil exceeded the background values of soil environment in Shandong Province. [Formula: see text] showed that only Hg in the soil was at the non-pollution to moderate pollution level. Meanwhile, sediments were polluted by Hg, Cd, and Zn, with their pollution level being higher than that of the soil. PERI showed that the soil presented moderate risk level and that the river sediment showed severe risk level. Hg and Cd exhibited the highest potential ecological risk. The results of the CA and PCA showed that the main sources of heavy metal pollution in the development zone are industrial activities, followed by atmospheric factors. Focus should thus be directed toward heavy metal pollution in development zones to protect human health and the soil environment.

Potential pathogen communities in highly polluted river ecosystems: Geographical distribution and environmental influence.

Risks of pathogenic bacteria to the health of both human beings and water ecosystems have been widely acknowledged. However, traditional risk assessment methods based on fecal indicator bacteria and/or pure culture are not comprehensive at the community level, mainly owing to the limited taxonomic coverage. Here, we combined the technique of high-throughput sequencing and the concept of metacommunity to assess the potential pathogenic bacterial communities in an economically and ecologically crucial but highly polluted river-the North Canal River (NCR) in Haihe River Basin located in North China. NCR presented a significant environmental gradient, with the highest, moderate, and lowest levels of pollution in the up-, middle, and downstream. After multiple analyses, we successfully identified 48 genera, covering nine categories of potential pathogens (mainly human pathogens). The most abundant genus was Acinetobacter, which was rarely identified as a pathogen bacterium in previous studies of NCR. At the community level, we observed significant geographical variation of community composition and structure. Such a high level of geographical variation was mainly derived from differed abundance of species among sections along the river, especially the top seven Operational Taxonomic Units (OTUs). For example, relative abundance of OTU1 (Gammaproteobacteria/Acinetobacter) increased significantly from upstream towards downstream. Regarding the underlying mechanisms driving community geographical variation, environmental filtering was identified as the dominant ecological process and total nitrogen as the most influential environmental variable. Altogether, this study provided a comprehensive profile of potential pathogenic bacteria in NCR and revealed the underlying mechanisms of community succession. Owing to their high abundance and wide geographical distribution, we suggest that potential pathogens identified in this study should be incorporated into future monitoring and management programs in NCR. By revealing the correlation between environmental factors and community composition, the results obtained in this study have significant implications for early warning and risk assessment of potential pathogen bacteria, as well as management practices in highly polluted river ecosystems.

Concentration, Distribution, and Potential Aquatic Risk Assessment of Metals in Water from Chott Merouane (Ramsar Site), Algeria.

In this study, 28 surface water samples were collected from eight different sites throughout the Chott Merouane. Samples were detected by atomic absorption spectrometry for Cd, Co, Cr, Cu, Fe, Ni, Mn, Pb, and Zn. The dissolved metal concentrations (mg/L) ranged from 0.05 to 0.90mg/L for Cd, 0.13-6.45mg/L for Co, bDL-2.05mg/L for Cr, 0.03-0.27mg/L for Cu, 0.34-7.41mg/L for Fe, 01.6-4.54mg/L for Ni, 0.15-1.19mg/L for Mn, 0.23-5.88mg/L for Pb, and 0.01-0.28mg/L for Zn. Compared with U.S. EPA standards and other freshwaters worldwide, the most mean concentration of metals in surface water of this salt lake are higher than the guideline levels of aquatic life. This was further corroborated by results from the water quality indices that Chott Merouane is seriously polluted by metals. The values of the metal pollution index indicated that metal pollution level was Cd > Pb > Ni > Fe > Cr > Cu > Mn > Zn, and those metals belong to moderate or high pollution level. The Nemerow pollution index further indicated that Chott Merouane was suffering from serious metal contamination. Based on geostatistics analyses, generally distributions of these metal contents decreased in the order of the North Chott Merouane ≈ the Northwest Chott Merouane > the Eastern part of Chott Merouane > the South Chott Merouane. The quality of water has drastically deteriorated due to the mixed source of anthropogenic inputs. Therefore, necessary conservation and management measures should be taken to improve the water quality of this Ramsar wetland.

Pollution indices and sources appointment of heavy metal pollution of agricultural soils near the thermal power plant.

Alluvial soils of valleys of the Danube and Mlave rivers represent priority development areas with favorable conditions for life, agriculture and tourism in eastern Serbia. Operation of the thermal power plant Kostolac results in the emission of potentially toxic pollutants into the air, water and land. The goals were to determine the soil pollution with inorganic pollutants using different pollution indices, to identify of the sources of pollutants by means of principal component analysis and the loading of each factor for individual element assessed by multi-linear regression analyses. Chemical characteristics of the studied area resulted in division of the area into four impact zones upon the distance from main pollutants (power plant blocks and ash disposal dumps). There was no established soil pollution with potentially toxic elements in bulk of the agricultural territory. Two principal components (PC1 and PC2) explained about 73% of variance. Three studied elements (As, Cu and Pb) showed anthropogenic origin of their most concentrations in soil, while other elements (Cd, Co, Cr, Ni and Zn) were of a natural (geological) origin. Single pollution index showed moderate pollution level by Ni. Integrated Nemerow pollution index showed low to no pollution levels, indicating slight ecological risk. There were no established limitations for agricultural production in the studied area, except for the only spot polluted by As due to the great flooding event in the studied year.