Low Potential Ecological Risk Research Articles (Page 1)

Lead (Pb) is a non-essential toxic heavy metal, and soil Pb pollution has been a significant global environmental concern. Elevated Pb concentrations have been reported in the world's largest continuous karst region, located in southwestern China. However, the speciation and origin of Pb in alluvial soils within this area remain poorly understood. In this study, a total of 122 alluvial agricultural soil samples and 319 carbonate rock samples were collected to settle these problems. The total Pb concentrations and chemical speciations were determined using chemical and BCR sequential extraction analysis. Potential sources of Pb were identified through Pb isotope analysis. Results showed that Pb contents in karst alluvial soils varied from 11.1 to 1386ppm, with an average of 54.6ppm and a median of 29.1ppm. Among the samples, 9.02% exceeded the risk screening threshold (70ppm), and only two samples surpassed the risk control threshold (400ppm). Both Enrichment Factor (EF) and Geo-accumulation Index (Igeo) assessments indicated low levels of Pb contamination. BCR analysis revealed that Pb was predominantly associated with reducible and residual fractions, accounting for 51.87 and 38.68% of the total Pb, respectively. The acid-soluble fraction was minimal (average 1.12%), suggesting a low potential ecological risk. Significant differences were observed in Pb isotopic compositions between potential natural and anthropogenic sources within the study area. Binary mixing model calculations indicated that natural sources contributed approximately 75.26% of the total Pb. Integrated analysis of BCR speciation and Pb isotopes suggested that anthropogenic Pb was primarily associated with non-residue phases. From carbonate rocks to soils, substantial losses of Ca, Mg, CO2 were observed, while Fe, Mn and Al were significantly enriched. The average Pb content increased from 2.32ppm in carbonate rocks to 54.6ppm in soils. These findings suggest that the significant loss of soluble elements and the fixation of Pb by Fe-Mn (hydro) oxides are the main mechanisms driving Pb enrichment in karst soils. Additionally, the extreme Pb enrichment in a few samples is likely linked to mining and smelting activities. Although Pb levels in most karst alluvial soils are generally low, the potential ecological risks should not be overlooked.

Abstract The accumulation of potential trace elements (PTEs) in water, sediment, and two fish species from El Bieda saline Lake, Wadi El-Natrun, Egypt was assessed to highlight the environmental status and health implications of these elements. Most PTE levels in lake water remained below the permissible limit, except for lead, selenium, and mercury which exceeded safety thresholds. Notably, sites B1 and B2 attained the highest PTEs concentrations in water and sediment, surpassing permissible limits for cadmium, mercury, and arsenic. The contamination factor (Cf) values for most PTEs were less than 1, indicating minimal pollution. The mean contamination degree (mCd) values varied from 0.5–0.70 suggested uncontaminated grade. The potential ecological risk index (PERI) values were less than 40, suggesting low potential ecological risk except for Hg. The flesh and liver of Oreochromis aurous and Tilapia zillii presented PTEs levels below permissible limits, except for lead, cadmium, arsenic, and chromium. O. aurous accumulated more PTEs than T. zillii. Despite the presence of PTEs, the estimated daily intake (EDI) and target hazard quotient (THQ) values remained below harmful thresholds, indicating no immediate health risks from fish consumption. These results underscore the need for ongoing management strategies and continuous monitoring to address the accumulation of hazardous trace elements in the ecosystem, thereby protecting environmental health and public safety.

To study the characteristics and sources of heavy metalsin thefarmland surrounding Tuo Lake Nature Reserve, a total of 615 topsoilsamples were collected from the study area. The concentrations ofeight heavy metal elements, including As, Cd, Cr, Pb, Hg, Cu, Ni andZn, in the topsoil were analyzed. Methods such as the geo-accumulationindex, enrichment factor, pollution load index, potential ecologicalrisk index, correlation analysis, cluster analysis, and principalcomponent analysis were employed to evaluate the pollution distributionsand investigate the sources of heavy metals. The results show thatthe average concentrations of As, Pb, and Hg in topsoil of the studyarea were higher than the background soil values. The degree of variationof Hg concentrations is significant, indicating substantial influencefrom external factors. The spatial distribution indicates that areaswith high concentrations of Cd, Pb, and As were primarily locatedin the southern region of Tuo Lake, while Cu, Ni, Zn, and Cr weremainly distributed along Tuo Lake and its banks. The geo-accumulationindex analysis indicates that only five points exhibited moderateHg pollution, and the majority of points in the survey area are classifiedas a clean state. The enrichment shows that only 13 samples exhibitedmoderate enrichment of Hg, while the majority of samples displayeddeficiency to minimal enrichment of heavy metals. The potential ecologicalrisk index reveals 0.2, 1.5, and 32.8% of samples reached moderateecological risk levels for As, Cd, and Hg, respectively, while theother five elements remained at low-risk levels. The comprehensivepotential ecological risk index indicates that the study area waspredominantly characterized by low potential ecological risk (96.4%),with only five points exhibiting high risks. Source analysis suggeststhat Cr, Cu, Ni, and Zn were primarily derived from natural sources,whereas Cd, Pb, and As were mainly attributed to industrial, agricultural,and transportation activities, and Hg mainly originated from agriculturalfertilizers and pesticides. These research results provide valuabledata to support the prevention and control of heavy metal pollutionin soil and ecological protection in the Tuo Lake Nature Reserve.

A global meta-analysis reveals effects of heavy metals on soil microorganisms.

Quantification of an integrated approach to heavy metal source apportionment and probabilistic health risk assessment in the black soil region of central Jilin Province, China.

Potentially toxic elements (PTEs) are the most important indicators of environmental pollution and represent a potential risk to the ecology and human health in industrial regions. Eight potentially toxic elements (Mn, Ni, Co, Cr, Pb, Zn, Cd, As) in soils formed on the territory of the industrial site of the Udachny Mining and Processing Division were considered in this study. The potential ecological risk index (RI) was calculated to determine environmental risks of soil contamination. The concentrations of PTEs decreased in the following order Mn > Ni > Zn > Co > Pb > Cr > As > Cd. In total, 19.51% of the sites in the study area exhibited a high potential ecological risk for Mn and Ni, while only 4.87% exhibited a low potential ecological risk for other PTEs. The greatest impacts on soil contamination are exerted by the areas of the Udachny and Zarnitsa pipes, tailings ponds, and the area’s highly mineralized water outlet. The results of correlation analysis (CA) and hierarchical cluster analysis (HCA) revealed that the same groups of elements were present: Co-Cr-Ni and Cd-Zn. The PMF findings demonstrate that the five main diverse sources of PTEs in this study area’s soils were natural, mining activities, transportation, and industrialization, as well as highly mineralized waters.

Dust samples were collected from three different industrial sites: Construction, chemical, and food industry sites of the Kirkuk Governorate, Northern Iraq. The heavy metals (Co, Ni, Cu, Zn, As, Mo, Sr, Cd, Pb, and U) in twenty-seven dust samples have been studied. A variety of indices have been utilized, including the contamination factor, contamination degree (Cdeg), geo-accumulation index (Igeo), enrichment factor, pollution load index, potential ecological risk, and risk index, as environmental pollution indicators. The finding refers to the concentration values of the elements, which are in the following descending arrangement: Sr>Zn>Cu> Pb> Ni> Co> U> Mo> As> and Cd. The result of the contamination factor indicated that the dust has low contamination with Ni and Sr, while the level of contamination with Co, Cu, As, and Mo is moderate. However, is considerably contaminated with Zn, Cd, Pb, and U. Significant enrichment of Co, Ni, Cu, Zn, Sr, and Mo was revealed by the EF findings. There is very high enrichment for As, Cd, Pb, and U. Depending on the calculated results of Igeo, the dust was unpolluted for Pb, Ni, Co, Cu, and Sr, nevertheless having unpolluted to moderately polluted for Zn, As, Mo, Cd, and U. According to the Er values, all the heavy elements in the studied sites revealed a low potential ecological risk, except Cd, which showed considerable potential ecological risk. All the studied sites have RI values that fall into the moderate ecological risk for heavy metals.

The Soku Gas Plant and associated oil facilities in South-south Nigeria has been a source of continuous discharge of oil spills and other industrial wastes to the ecosystems surrounding it. Standard methods were used to analyse the concentrations of heavy metals (Zn, Pb, Ni, Cr and Cd) and PAHs in the sediments. The result of this study revealed that the concentration of both PAHs and heavy metals were within the PEL and TEL guideline values. Five methods of pollution assessment of metals were conducted including the Geo-accumulation Index (I-geo), Contamination Factor (Cf), Pollution Load Index (PLI), Potential Ecological Risk Index (PERI) and Metal Toxicity. The result of CF, CD, and PLI In this study, Cd had the highest and Cr had the lowest CF average values among the five metals studied. The contamination factor in the study area showed higher levels for cadmium and lower levels for chromium in all stations while the calculated PERI for all the sample stations in the study area indicated low potential ecological risk. The potential ecological risk index (PERI) can be ranked in the following order: Station 3 (Pangapingi)> Station 4 (Soku Jetty) > Station 2(Gas plant) > Station 1(Elem Sangama). Spatial distribution of single risk indices (Eir) showed moderate to low risk. The I-geo classes for the study area varied across metals and sites ranging from uncontaminated to moderately contaminated. Clean-up of oil pollution and payment of compensation as required by law and convention was recommended.

Distribution and migration of pollutant elements during municipal solid waste incineration fly ash melting in a pilot-scale furnace.

Spatial distribution, sediment‒water partitioning, risk assessment and source apportionment of heavy metals in the Golmud River-Dabson Salt Lake ecosystem.

The land use in agricultural areas contributes to economic growth while concurrently accompanied by a series of environmental pollution issues. Xingguo County, Ganzhou City, Jiangxi Province, is a typical agricultural area with selenium-rich soil, and the rice and navel oranges grown there have high nutritional value. This study analyzed the distribution of heavy metals in the soil of this area through the kriging interpolation method, evaluated the risks of heavy metals in the soil using different pollution index methods, and quantitatively analyzed their sources using principal component analysis (PCA) and positive matrix factorization (PMF), with the aim of protecting the ecological resources of this area and providing theoretical references for avoiding heavy metal pollution of crops in the soil. The research results indicate the following: (1) Based on the background values of Ganzhou, Jiangxi Province, all heavy metals have caused pollution to the soil except for As and Hg, among which Cd poses the highest potential ecological risk in the study area. According to the values of the Environmental Quality Standards for Soil (EQSS), the concentrations of heavy metals have not exceeded the standards and have relatively low potential ecological risks. (2) In terms of health risks, all soil heavy metals basically do not bring non-carcinogenic risks but acceptable carcinogenic risks to adults and children, except for Cd. The carcinogenic and non-carcinogenic risks of soil heavy metals for children are higher than those for adults, and the main exposure route is ingestion. Among different land use types, the carcinogenic and non-carcinogenic risks of soil heavy metals in orchards are the highest. (3) Combining the kriging interpolation method and the PCA and PMF models, it can be determined that there are two main sources of heavy metals in the study area: one is natural and the other is anthropogenic. Among the anthropogenic sources, agricultural sources contribute the most to soil heavy metal pollution. Through these research results, it can be found that soil heavy metal detection should be conducted in agricultural land, and risk-based management measures should be implemented.

The moss bag technique was applied on Kamchatka to assess the effect of Shiveluch volcano on the air quality. Moss bags were exposed in settlements located at different distances from the volcano and affected by ashfall to varying degrees. The inductively coupled plasma optical emission spectrometry was used for the determination of the content of Al, Ba, Co, Cd, Cr, Cu, Fe, Mn, P, Pb, Sr, S, V, and Zn in both exposed and unexposed moss samples. Relative accumulation factor revealed enrichment of mosses exposed in the area affected by ashfall with Al, Cr, V, and Zn. Correlation and principal component analysis allowed to identify elements of volcanogenic, geogenic, and anthropogenic origin. Ecological risk values less than 150 indicate low potential ecological risk in the region. Active moss biomonitoring can be considered a cheap and efficient tool for in-depth study of the influence of volcanic activity on air quality on the peninsula.

The hydrosphere becomes contaminated secondarily by accumulated heavy metals in sediments which may be released into the aquatic environment, thereby increasing the risks to human health. To evaluate the pollution characteristics of heavy metals in surface water sediments of Ifite Ogwari, nine sediment samples were collected from surface water sources used by the residents for drinking and other household activities. The concentrations of eight heavy metals: cadmium (Cd), chromium (Cr), copper (Cu), Iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) were analyzed using Atomic Absorption Spectroscopy (AAS). Enrichment Factor (EF), Contamination Factor (CF), Geoaccumulation index (Igeo), Potential Ecological Risk Index (PERI) and Risk Assessment Code (RAC) were conducted. Results of heavy metal concentration indicated that Cu < Cr < Ni < Pb < Cd < Zn < Mn < Fe based on the average metal concentration. Human health assessment showed high cancer risk for children and adults in a ratio of 1 in 10000 population. PERI indicated that sediment samples from Iyiutu and Ahala streams have low potential ecological risk while samples from Ube, Tabasi and Ogbu showed moderate ecological risk whereas samples from Isiachala, Nabaloku and Atammele streams as well as Omambala river sediments were high. RAC shows no ecological risk by Zn, Pb, Ni, Cu and Mn but in Omambala river, Cr and Cd contributed to ecological risk while Fe contributed to ecological risk in all the samples. Consequently, there is need for proper monitoring from health base evaluation and conscious effort to live in a clean environment devoid of any kind of exposure.

Soil samples were collected from Sangaw, Qadir Karam, and Takiat Gabbary sites of Chamchamal agricultural soil Sulaymaniya Governorate, Northeastern Iraq. The heavy metals Co, Cr, Cu, Ni, Cd, Zn, Pb, As, and Mn. in Eighteen soil samples were studied and used as an indicator for pollution by using many indices such as the contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo), pollution load index (PLI), pollution ecological risk (Er), and risk index (RI). The results showed that the heavy metal concentration values were as follows: Mn&gt; Ni&gt; Zn&gt; Cr&gt; Cu&gt; Pb&gt; Co&gt; As&gt; Cd. The CF data showed that the soil in the study area has low contamination with Co, Cr, Cu, and Mn and moderate contamination with Ni, Pb, Zn, and As. Also, the soil samples are considerably contaminated by Cd and As in the Qadir Karam site. According to the results of Igeo, the soil was unpolluted for Co, Cr, Ni, Cu, Pb, Zn, and Mn, while being unpolluted to moderately polluted for Cd and As. The EF calculation results indicated that Co, Cr, Cu, and Mn have deficient to minimal enrichment, and have moderate enrichment for Ni, Pb, and Zn, while, for Cd and As is significant enrichment. According to the Er values, all the heavy metals in the studied sites reflect a low potential ecological risk. The risk index (RI) value is classified as moderate ecological risk for heavy metals in all sampling sites.

Purpose: Water is an important fundamental resource to support human, animal and plant life. Global reports highlight widespread contamination of water sources due to various human activities. The high level of anthropogenic activity in the Lake Maninjau area, both in agriculture, animal husbandry and settlements, has an impact on decreasing the quality of the lake as indicated by the quality of the sediment and lake water. The research aims to evaluate heavy metal concentrations in sediments and heavy metal processing strategies. Theoretical Framework: Lake Maninjau is one of the lakes in Indonesia that experiences pollution. Recently, this lake has become one of the priority lakes to reduce high levels of pollution (Ministry of the Environment, 2011). The source of Lake Maninjau pollution comes from floating net cages, agriculture, settlements and livestock. This is shown by the accumulation of heavy metals in waters and sediments which is important information for the survival of fish, humans, plants, microorganisms and other aquatic ecosystems (Wibowo et al. , 2022a). Method: The five distinct sample locations were chosen to represent various activities within the Maninjau Lake region, as outlined in Figure 1 and Table 1. Sediment was taken at the surface at a depth of 0-10 cm. samples were processed and analyzed at the P3IN soil science laboratory, Andalas University, as well as assessing sediment quality through Geoaccumulation (Igeo), enrichment factor (EF), pollutant load index (PLI), contamination factor (CF), and potential ecological risk (PER) in five location of Lake Maninjau. Results and Discussion: The results of the research showed that Cu concentrations varied from 0.195 mg/kg to 0.290 mg/kg, with a moderate average of 0.246 mg/kg. Pb metal ranges between 0.325 mg/kg-0.412 mg/kg, with an average of 0.356 mg/kg. Cd metal 0.301 mg/kg- 0.365 mg/kg. The Igeo values for the metals Cr, Cd, Pb, and Cu at the five locations show Igeo &lt; 0, meaning they are not contaminated with heavy metals. The Potential Ecological Risk Index (PER) ranges from 14.8303-19.0094, which shows the low potential ecological risk related to heavy metal pollution Research Implications: It is hoped that this research can help stakeholders in managing the Maninjau Lake ecosystem against potential heavy metal contamination that threatens the lake ecosystem Originality/Value: The use of combination or hybrid technologies to treat heavy metals from wastewater is an effective solution, but it is important to carefully consider and mitigate potential negative impacts on the environment and human health.

Contamination of college campus dust with heavy metals and the calculation of their ecological and health risks to the students and staff did not receive much attention except in recent years. This study aims to assess the ecological and human health risks of Cd, Cr, Cu, Pb, and Zn in interior dust of College of Science/University campus. An atomic absorption spectrophotometer was utilized to estimate the samples that were collected from 46 locations of the college campus including: classrooms, offices, and laboratories. The Pb, Cu, Cr and Zn metals in the interior dust of the College of Science pose low potential ecological risk, whereas Cd generates medium potential ecological risk. The gained results showed that the student and staff of the College are exposed to low non-cancerous health risks (HI < 1) caused by Cd, Cr, Cu, Pb, and Zn in interior dust. The total lifetime carcinogenic risks (TLCR) of Cd, Cr, and Pb are within the acceptable safe limit (10-6-10-4). The low non-carcinogenic health risks of Cd, Cr, Cu, Pb, and Zn and that the carcinogenic health risks of Cd, Cr and Pb fall within acceptable safe limits, measured in the interior dust of the campus of the College of Science, does not mean neglecting the continuous assessment of those risks.

A study of the stabilization and solidification of heavy metals in co-vitrification of medical waste incineration ash and coal fly ash

The continuous use of fertilizers and fungicides has triggered copper (Cu) contamination in cacao soils in Ghana, which is a critical issue for the ecological risk and health safety of cacao products. In this study, we investigated Cu pollution, bioavailability, and ecological risk in soil and determined the Cu levels in the cacao nib, shell, and pod husk. Soils were collected at two soil depths (0–15 ​cm and 15–30 ​cm) from 20 cacao farms, under conventional (CCM: chemical-based fertilizers) and organic (OCM: organic-based fertilizers) management practices together with pods. The total Cu concentration ranged from 67.6 to 96.8 ​mg ​kg−1 in OCM and 28.5–33.9 ​mg ​kg−1 in CCM soil, which decreased with soil depth. The enrichment factor revealed minimal Cu enrichment, which was attributed to anthropogenic activity (fungicide and fertilizer applications). The contamination factor and geoaccumulation index values were low for the CCM soils, and moderate for the OCM soils. Both management systems pose a low potential ecological risk to soil biota activity. Bioavailable Cu extracted with CaCl2, NH4OAc, and DTPA was dominant in CCM soil and decreased with soil depth. The Cu concentration in cacao plants decreased in the order of shell > pod husk > nib, with nib-Cu being below the threshold (50.0 ​mg ​kg−1) of contamination. The results from the pairwise correlation analysis show that CaCl2-available Cu is better for evaluating the Cu content in cacao plants. This study reveals the pollution levels associated with cacao management practices, thus providing valuable insights for developing appropriate mitigation strategies.

Accumulation of typical persistent organic pollutants and heavy metals in bioretention facilities: Distribution, risk assessment, and microbial community impact

Feasibility of ultrafiltration-based processes for simultaneous removal of trace-level ofloxacin and sulfamethazine from the effluent of WWTPs