Pollution Risk Assessment Research Articles

Multimedia distribution and health risk assessment of typical organic pollutants in a retired industrial park

Multimedia distribution and health risk assessment of typical organic pollutants in a retired industrial park

A comparative analysis of multi-biomarker responses to environmental stress: Evaluating differences in landfill leachate and pathogenic oomycete effects between wild and captive Salmo trutta

Phenotypic plasticity is one of the major means by which organisms can manage with environmental factor changes. Captivity-related stress and artificial rearing settings have been shown to dramatically alter fish response plasticity in terms of physiology, behavior, and health, potentially reducing overall fitness and fish survival. Understanding the variations in plasticity between captive-bred (kept in a homogenous environment) and wild fish populations in response to varied environmental pressures is becoming increasingly important, particularly in risk assessment research. In this study, we investigated whether captive-bred trout (Salmo trutta) are more susceptible to stress stimuli than their wild counterparts. In both wild and captive-bred trout, we investigated a battery of biomarkers that depicts the effects at various levels of biological organization in response to landfill leachate as a chemical pollutant, and after exposure to pathogenic oomycetes Saprolegnia parasitica. According to the findings, wild trout were more susceptible to chemical stimuli based on cytogenetic damage and catalase activity changes, whereas captive-bred trout were more sensitive to biological stress as evidenced by changes in overall fish activity and increasing cytogenetic damage in gills erythrocytes. Our findings emphasize the significance of exercising caution when conducting risk assessments of environmental pollutants using captive-bred animals, especially when seeking to extrapolate hazards and better understand the consequences of environmental contamination on wild fish populations. Additional comparative studies are required to investigate the impact of environmental stressors on multi-biomarker responses in both wild and captive fish populations in order to uncover changes in the plasticity of various traits that can result in adaptation or maladaptation to environmental stimuli within these fish populations, affecting data comparability and transferability to wildlife.

Pollution Characteristics and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Farmland Soil and Crops in the Suburbs of Urumqi

In order to understand the occurrence of PAHs in soil and crops, the enrichment capacity of different crops for PAHs, and the distribution characteristics of PAHs in different parts of crops, the crops and soil planted in the farmland around Urumqi were studied as examples. Samples were collected in the farmland gathering area in the suburb of Urumqi in July 2021. A total of 100 crop samples were collected, including 21 crop species and 45 surface soil samples. The results showed that 16 types of PAHs were detected in the soil and crops. The total concentration of PAHs in farmland soil ranged from 19.06 to 1870.86 μg·kg-1, and the average concentration was 127.40 μg·kg-1. Seven carcinogenic PAHs accounted for 42.85%-79.20% of the 16 types of PAHs, among which BaP was the main pollutant in the soil. Through the characteristic ratio method, it was found that the main sources of PAHs in the soil were biomass and coal combustion. Total PAHs in crops ranged from 1.86 μg·kg-1 to 974.05 μg·kg-1, with an average of 303.30 μg·kg-1. Different crops had different enrichment capacities for PAHs. Among the 21 crops sampled, the accumulative content of PAHs in pumpkin was the highest (431.75 μg·kg-1). In leaf vegetable crops, the content of PAHs in leaves was higher than that in roots and fruits. In fruit and vegetable crops, the PAH content in fruit was higher than that in the root or leaf. There was a significant correlation between high cyclic PAHs in soil and PAHs in plant leaves. The health risk assessment of PAHs in crops showed that dietary intake had potential carcinogenic risk and even had high carcinogenic risk in adult male and female groups, which requires further attention.

Simulation Analysis of the Dispersion of Typical Marine Pollutants by Fusion of Multiple Processes

The rapid development of coastal economies has aggravated the problem of pollution in the coastal water bodies of various countries. Numerous incidents of massive-scale marine life deaths have been reported because of the excessive discharge of industrial and agricultural wastewater. To investigate the diffusion of typical pollutants after discharge, in this study, a multi-process fusion simulation analysis model of pollutants under the action of ocean currents was established based on the concentration analysis method. Furthermore, key technologies involved, such as the parameter value, data selection, and visualization, were investigated. The iterative analysis and programming realization of three independent sub-processes, such as pollutant diffusion and transport, and the drift path and concentration distribution of pollutants after their discharge into the sea, were visualized. The case study revealed that the increase in the concentration of pollutants in the ocean was affected by the diffusion sub-process, and the transport sub-process plays a critical role in the long-distance transport of pollutants. The proposed method can provide technical support for marine environmental risk assessment and dynamic tracking of marine pollutants.

The response of non-point source pollution to land use change and risk assessment based on model simulation and grey water footprint theory in an agricultural river basin of Yangtze River, China

Non-point source (NPS) pollution has gradually become the main source of water environmental pollution with the rapid economic development during the recent decades, especially for the economically developed Yangtze River Basin of China. Due to rapid urbanization, the pressure of the water environment in the Poyang Lake basin (PYLB) has been increasing. In this study, the spatial and temporal variations of NPS pollution loads including total nitrogen (TN) and total phosphorus (TP) in the PYLB during the period 2003–2012 were firstly investigated by using the SWAT; then the changes in NPS pollution loads under different land use types were identified by using the SWAT, land use transition matrix, statistical analysis and scenario analysis methods; finally, the NPS pollution risk assessment were achieved by means of the grey water footprint theory. The results showed that the NPS pollution loads in the PYLB were concentrated from April to June with a large inter-annual variability. The Gan River basin contributed the largest proportion of pollutants entering into the Poyang lake while the Xiu River basin produced the smallest pollution loads. Under the background of the policy of “Grain for Green Project” since 2002, the areas of cultivated land, grassland and bare land decreased during the period 2000–2010, while those of forest land and settlement increased. As the main source of NPS pollution, the area of cultivated land has decreased, while the unit load intensity under cultivated land has significantly increased. By calculating the annual GWF of TN and TP loads and their corresponding WPL, which all showed an upward trend. The results obtained in this study have practical significance for reducing the NPS pollution loads in the PYLB and controlling the environmental pollution in the Yangtze River.

Risk assessment of microplastic pollution in an industrial region of Bangladesh

Despite the high potential for microplastics (MPs) pollution in Bangladesh, the presence of MPs in the industrial region has largely been unexplored in Bangladesh. So, this study was conducted to determine whether MP pollution is prevalent in the industrial soil of Bangladesh and the extent of its toxicity. To examine MPs, a total of 12 soil samples were collected from the industrial region of Narayanganj, and a stereoscopic microscope was used to visually identify the MPs. Prior to that the technique of density separation and sieving was applied to extract MPs from those 12 soil samples. Among the twelve investigated samples, a total of 151 MPs (Mean: 12.6 ± 7.9 particles kg−1) were identified, which were mostly white and ranged in size from 0.5 to 1 mm. Different types of MPs according to their shapes such as fibers (60.3%), fragments (19.2%), films (10.6%), and foam (9.9%) have been detected. 7 MPs (Mean: 0.58 ± 0.79) have been found in 3 urban farmland sites, 15 MPs (Mean: 1.87 ± 1.81) in two near metropolitan areas, and 129 MPs (Mean: 4.6 ± 4.39) in 7 industrial locations. Five polymers were identified by μ-FTIR, among which Polyamide predominated, followed by Polypropylene. According to risk assessments, the region falls under hazard categories II and III, suggesting a moderate to high risk. This paper gives thorough information on the toxicity of MP in an industrial location; therefore, it may be useful in the development of effective methods to address environmental issues.

Comprehensive assessment of anthropogenic loads and consequences of their influence on the environmental state of water bodies (as exemplified by the Gruzka River, Kirovohrad Region)

The relevance of the research is determined by the need of developing and improving the methods for assessing the extent and consequences of anthropogenic loads' impact on water bodies.
 The research was carried out as part of the study and research activities conducted by the Department of Hydroecology and Water Research of OSENU. It is dedicated to the topic "Assessment of Anthropogenic Impact on Aquatic Ecosystems".
 The purpose of the work is to determine the environmental status of water bodies based on the comprehensive approach (calculations related to the consequences of anthropogenic loads' impact on water resources and the environmental state of surface waters, including assessment of pollution risks and failure to achieve environmental objectives).
 Research methods include assessment of the characteristics of unstudied rivers' water resources in terms of hydrology based on the used meteorological data (climate-runoff model); assessment of anthropogenic loads' impact on water resources and on prospects of achieving a good environmental state of water bodies in accordance with the requirements of the EU's WFD; assessment of environmental risks based on the Prob function application and creation of a scale of water quality indicators and risks correspondence.
 Determination of a comprehensive indicator of the Gruzka River's water resources use showed that reduction of water flow characteristics due to climate changes does not significantly affect the river's environmental condition that remains "unsatisfactory".
 It was also established that household wastewater is the main pollutant of the Gruzka River that supplies water to reserve water reservoir Lelekivske (City of Kropyvnytskyi, Kirovohrad Region). Almost all criteria related to assessment of the consequences of anthropogenic loads (wastewater discharge, plant and animal husbandry, chemical and physico-chemical parameters) indicate a risk of not achieving a good ecological state. During the modern period, the river continues suffering from significant anthropogenic influence whose level is close to the limit of ecosystem sustainability.
 It was established that the use of ER environmental risk that is based on the Prob indicator complements the information about the river's environmental state.
 The proposed comprehensive approach can be used for water bodies that remain unsufficiently studied in terms of hydrology and hydrochemistry.

WITHDRAWN: Sediment pollution in coastal and marine environments

Sediment pollution in coastal and marine environments has emerged as a pressing concern due to its far-reaching ecological, environmental, and human health impacts. This Special Issue of the Marine Pollution Bulletin assembles a diverse range of studies investigating sediment pollution, its causes, and potential mitigation strategies, covering topics such as geophysical assessment of anthropogenic activities, biological responses to pollution, contamination, and ecological risk assessments, and microplastics in coastal sediments. The findings emphasize the need for effective monitoring, management, and interdisciplinary research to address the multifaceted challenges posed by sediment pollution. As the global population grows and human activities expand, it is essential to prioritize sustainable practices and policies to minimize anthropogenic impacts on coastal and marine ecosystems. By advancing collective knowledge and sharing best practices, we can work towards ensuring a healthier and more resilient future for these crucial ecosystems and the lives they support.

Potential linkage between WWTPs-river-integrated area pollution risk assessment and dissolved organic matter spectral index.

The direct discharge of wastewater can cause severe damage to the water environment of the surface water. However, the influence of dissolved organic matter (DOM) present in wastewater on the allocation of DOM, nitrogen (N), and phosphorus (P) in rivers remains largely unexplored. Addressing the urgent need to monitor areas affected by direct wastewater discharge in a long-term and systematic manner is crucial. In this paper, the DOM of overlying water and sediment in the WWTPs-river-integrated area was characterized by ultraviolet-visible absorption spectroscopy (UV-vis), three-dimensional excitation-emission matrix combined with parallel factor (PARAFAC) method. The effects of WWTPs on receiving waters were investigated, and the potential link between DOM and N, P pollution was explored. The pollution risk was fitted and predicted using a spectral index. The results indicate that the improved water quality index (IWQI) is more suitable for the WWTPs-river integration zone. The DOM fraction in this region is dominated by humic-like matter, which is mainly influenced by WWTPs drainage as well as microbial activities. The DOM fractions in sediment and overlying water were extremely similar, but fluorescence intensity possessed more significant spatial differences. The increase in humic-like matter facilitates the production and preservation of P and also inhibits nitrification, thus affecting the N cycle. There is a significant correlation between DOM fraction, fluorescence index, and N, P. Fluorescence index (FI) fitting of overlying water DOM predicted IWQI and trophic level index, and a(254) fitting of sediment DOM predicted nitrogen and phosphorus pollution risk (FF) with good results. These results contribute to a better understanding of the impact of WWTPs on receiving waters and the potential link between DOM and N and P pollution and provide new ideas for monitoring the water environment in highly polluted areas.

Preliminary assessment of potential pollution risks in soils: case study of the Córrego do Feijão Mine dam failure (Brumadinho, Minas Gerais, Brazil)

ABSTRACT The magnitude of the impacts caused by tailing dam failures represents, in a very short space of time, the potential risks of metals on the environment along time. In riparian soils affected by the failure of Córrego do Feijão Mine dam (Brazil), potential pollution risks were estimated using geochemical indices. Based on background and baseline values, strong anthropogenic interferences in the soil metal enrichment has been evidenced after collapse. Abnormal levels of Cd (1.01 mg kg−1), Cr (80 mg kg−1), As (28 mg kg−1), Cu (90 mg kg−1), Pb (80 mg kg−1), and Ni (35 mg kg−1) in soils were associated to the highest risks. Overall, the potential ecological risk (>600) and pollution load (>5) indices indicated Brumadinho, Mário Campos, Betim and São Joaquim de Bicas as the areas most affected by the tailings spill. For the most areas, the geological accumulation index calculated from baseline values showed high commitments in soil quality, with pollution degree from moderately to strongly polluted (from 3 to 5, for Hg and Ni) and extremely polluted (>5, for Cd and Pb). In order to maintain the functional ecosystem integrity, restorative and reparative actions must be urgently carried out in these areas

Emergency risk assessment of sudden water pollution in South-to-North Water Diversion Project in China based on driving force–pressure–state–impact–response (DPSIR) model and variable fuzzy set

Emergency risk assessment of sudden water pollution in South-to-North Water Diversion Project in China based on driving force–pressure–state–impact–response (DPSIR) model and variable fuzzy set

Photodegradation of the Fungicide Isopyrazam in Aqueous Solution: Kinetics, Photolytic Pathways, and Aquatic Toxicity.

Photodegradation behavior of a new fungicide isopyrazam in water under simulated sunlight and ultraviolet (UV) irradiation was studied. The photolysis half-life (t1/2) of isopyrazam in purified water was 195 h under simulated sunlight, which was decreased to 46-88 h, 28-51 h, and 13-18 h in the presence of NO3-, Fe3+, and riboflavin, respectively. UV irradiation accelerated the photolysis of isopyrazam with a half-life of 30 min and revealed varied degradation rates in acidic (0.011 min-1), neutral (0.024 min-1), and alkaline solutions (0.022 min-1). Nine transformation products under simulated sunlight and UV were found, and photolytic pathways were proposed to include cleavage of C-N bonds, hydroxylation, nitration, demethylation, dehydrofluorination, and photoisomerization. The acute toxicity of defluorinated isopyrazam (TP 4) and the chronic toxicity of isomerized isopyrazam (TP 9) to aquatic organisms were approximately twice that of isopyrazam. These findings provide insights into environmental risk assessment and management of water pollution.

Pollution Characteristics and Risk Assessment of Antibiotics in Beiyun River Basin in Beijing

To investigate the pollution characteristics and risk levels of antibiotics in water of the Beiyun River Basin in Beijing, the concentration of antibiotics was analyzed by using the solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) method. The results showed that seven types of four categories of antibiotics were detected in the samples from 12 sampling points; the total concentration of antibiotics including sulfapyridine, clarithromycin, azithromycin, roxithromycin, erythromycin, ofloxacin, and lincomycin ranged from 59.19 to 703.44 ng·L-1. Among these antibiotics, the detection rate of clarithromycin, azithromycin, roxithromycin, ofloxacin, and lincomycin was 100%; that of erythromycin was 41.67%; and that of sulfapyridine was 33.33%. Compared with that in some rivers in China, the Azithromycin, Erythromycin, and Clarithromycin in the Beiyun River Basin were at a relatively high level. The ecological risk assessment results showed that the most sensitive species was algae. The health risk quotients indicated that sulfapyridine, lincomycin, roxithromycin, azithromycin, and erythromycin presented no risk for every age group, whereas the health risk of clarithromycin was at a low level.

Pollution Characteristics and Risk Assessment of Heavy Metals in Surface Dusts and Surrounding Green Land Soils from Yellow River Custom Tourist Line in Lanzhou

In order to investigate the contamination levels of dust and its surrounding green land soil heavy metal pollution and potential ecological and health risks in the scenic areas of urban waterfront parks, the gardens, squares, and theme parks of the Yellow River Custom Tourist Line in Lanzhou were selected as the research area, using 27 dust samples and 26 soil samples from its surrounding green lands. The contamination characteristics and potential ecological risks of eight heavy metals (Cr, Ni, Cu, Zn, As, Cd, Hg, and Pb) were evaluated using the geo-accumulation index (Igeo), single-factor pollution index (Pi), Nemerow integrated pollution index (PN), and improved potential ecological risk index (RI). The human health risk assessment was also evaluated using the exposure risk model. The results showed that the average concentrations of the other heavy metals in the surface dusts were higher than the background values of Gansu Province and Lanzhou City, except that the As mean concentrations in the surface dusts and the surrounding green land soils were slightly lower than the Gansu Province background values. For its surrounding green land soils, the mean concentrations of the other heavy metals (Cu, Zn, Cd, Hg, and Pb) exceeded the soil background values of Gansu Province and Lanzhou City, whereas the Cr and Ni mean concentrations were lower than their corresponding soil background values of Gansu Province and Lanzhou City. The geo-accumulation and single-factor pollution indices demonstrated that a slight to moderate pollution of Cr, Cu, Zn, Cd, Hg, and Pb occurred in surface dusts, and Cu, Zn, Cd, Hg, and Pb appeared in varying degrees of contamination levels in its surrounding green land soils. The Nemerow integrated pollution index analysis manifested that the overall contamination status of the study areas was between slightly and heavily polluted. The potential ecological risk index suggested that Cd and Hg were recognized as significant pollutant elements and that the RI of the other heavy metals were all below 40, presenting slight ecological risk. The health risk assessment indicated that ingestion was the dominant exposure pathway for heavy metals from the surface dusts and the surrounding green land soils, and no carcinogenic and noncarcinogenic risks posed threats to adults and children.

Groundwater Pollution Risk Assessment in Plain Area of the Yarkant River Basin

Groundwater pollution risk assessment is an effective method to manage groundwater resources and prevent groundwater pollution. The DRSTIW model was used to evaluate the groundwater vulnerability in a plain area of the Yarkant River Basin, and factor analysis was used to identify pollution sources for pollution loading evaluation. The functional value of groundwater was estimated by considering both the mining value and the in-situ value. The entropy weight method and the analytic hierarchy process (AHP) were used to determine the comprehensive weight, and a groundwater pollution risk map was generated based on the overlay function of ArcGIS software. The results showed that the natural geological factors such as large groundwater recharge modulus, wide recharge sources, strong permeability of soil surface and unsaturated zone, and shallow groundwater depth facilitated pollutant migration and enrichment, resulting in a higher overall groundwater vulnerability. Very high vulnerability and high vulnerability areas were mainly distributed in Zepu County, Shache County, Maigaiti County, Tumushuke City, and the eastern part of Bachu County. The pollution loading of groundwater was generally low, the main pollution sources were point source pollution caused by water-rock interaction, non-point source pollution caused by pesticides and fertilizers, and point source pollution caused by industry and life. The overall functional value of groundwater was low because of human economic activities, fine water quality, and good habitat quality. Groundwater pollution risk was generally low, and very high and high pollution risk areas accounted for 20.7% of the study area, mainly distributed in Shache County, Zepu County, Maigaiti County, Tumushuke City, and the western part of Bachu County. Natural conditions such as strong aquifer permeability, weak groundwater runoff conditions, large groundwater recharge modulus, low vegetation coverage, and strong water-rock interaction, coupled with frequent human activities such as application of agricultural fertilizers and discharge of industrial and domestic sewage, made the groundwater pollution risk higher in these areas. Groundwater pollution risk assessment provided strong data support for the optimization of the groundwater monitoring network and the prevention of groundwater pollution.

Bioaccumulation and elimination, acute toxicity analysis and risk assessment of diflubenzuron in common carp (Cyprinus carpio)

Diflubenzuron has been applied in agriculture and aquaculture, and its residues in ecological environment and food chain could result in chronic exposure and long-term toxicity effects for human health. However, limited information is available regarding diflubenzuron levels in fish and associated risk assessment. This study performed the analysis for dynamic bioaccumulation and elimination distribution of diflubenzuron in carp tissues. The results indicated that diflubenzuron was absorbed and enriched by fish body along with higher enrichment in lipid-rich tissues of fish. The peak concentration in carp muscle reached 6-fold of diflubenzuron concentration in aquaculture water. The median lethal concentration (LC50) of diflubenzuron at 96 h was 12.29 mg/L, presented low toxicity to carp. Risk assessment results showed that the chronic risk from dietary exposure to diflubenzuron through carp consumption for Chinese residents of children and adolescents, adults and elderly people were acceptable, while posed a certain risk for young children. This study provided the reference for pollution control, risk assessment and scientific management of diflubenzuron.

Pollution and health risk assessment of rare earth elements in Citrus sinensis growing soil in mining area of southern China.

Analyzing the pollution and health risk of rare earth elements (REEs) in crop-growing soils around rare earth deposits can facilitate the improvement of REE mining-influenced area. In this study, pollution status, fraction and anomaly, plant accumulation characteristics, and potential risks of REEs (including heavy and light rare earth elements, HREEs and LREEs) in C. sinensis planting soil near ion-adsorption deposits in southern Ganzhou were analyzed. The influence of the soil environment on REEs in soil and fruit of C. sinensis was also explored. The geo-accumulation index (Igeo) and ecological risk index(RI) were used to analyze the pollution potential and ecological risks of REEs in soils, respectively. Health risk index and translocation factor (TF) were applied to analyze the accumulation and health risks of REEs in fruit of C. sinensis. The influence of soil factors on REEs in soil and fruit of C. sinensis were determined via correlation and redundancy analysis. Comparison with background values and assessment of Igeo and RI indicated that the soil was polluted by REEs, albeit at varying degrees. Fractionation between LREEs and HREEs occurred, along with significant positive Ce anomaly and negative Eu anomaly. With TF values < 1, our results suggest that C. sinensis has a weak ability to accumulate REEs in its fruit. The concentrations of REEs in fruit differed between LREEs and HREEs, with content of HREE in fruit ordered as Jiading > Anxi > Wuyang and of LREE in fruit higher in Wuyang. Correlation and redundancy analysis indicated that K2O, Fe2O3 and TOC are important soil factors influencing REE accumulation by C. sinensis, with K2O positively related and Fe2O3 and TOC negatively related to the accumulation process.

Soil heavy metal(loid) pollution and health risk assessment of farmlands developed on two different terrains on the Tibetan Plateau, China

The quality of farmland soils on the Tibetan Plateau is important because of the region's ecological vulnerability and their close link with local food security. Investigation on the pollution status of heavy metal (loid)s (HMs) in the farmlands of Lhasa and Nyingchi on the Tibetan Plateau, China revealed that Cu, As, Cd, Tl, and Pb were apparently enriched, with the soil parent materials being the primary sources of the soil HMs. Overall, the farmlands in Lhasa had higher contents of HMs compared to those in Nyingchi, which could be attributed to the fact that the former were mainly developed on river terraces while the latter were mainly developed on the alluvial fans in mountainous areas. As displayed the most apparent enrichment, with the average contents in the vegetable field soils and grain field soils of Lhasa being 2.5 and 2.2 times higher compared to those of Nyingchi. The soils of vegetable fields were more heavily polluted than those of grain fields, probably due to the more intensive input of agrochemicals, particularly the use of commercial organic fertilizers. The overall ecological risk of the HMs in the Tibetan farmlands was low, while Cd posed medium ecological risk. Results of health risk assessment show that ingestion of the vegetable field soils could pose elevated health risk, with children facing greater risk than adults. Among all the HMs targeted, Cd had relatively high bioavailability of up to 36.2% and 24.9% in the vegetable field soils of Lhasa and Nyingchi, respectively. Cd also showed the most significant ecological and human health risk. Thus, attention should be paid to minimize further anthropogenic input of Cd to the farmland soils on the Tibetan Plateau.

Spatial Distribution and Associated Risk Assessment of Heavy Metal Pollution in Farmland Soil Surrounding the Ganhe Industrial Park in Qinghai Province, China

The farmland around the industrial areas in the Upper Yellow River is crucial for agricultural production but is vulnerable to contamination from the surrounding industries. This research focused on analyzing the spatial distribution and environmental risks of heavy metal pollution in the farmland around the Ganhe Industrial Park in the Qinghai–Tibet Plateau. A total of 138 surface soil samples were collected, and the concentration of seven heavy metals (Cd, As, Pb, Cr, Cu, Ni, and Zn) was analyzed using the random forest (RF) model. Pollution indicators, including the pollution index and Nemero index, were used to evaluate the pollution levels of soil heavy metals. The human health and ecological risks were estimated using the hazard index (HI) and the potential ecological risk index (RI). Cd and Zn were identified as the primary soil pollutants in the study area, with Cd being more concentrated than other heavy metals. Heavy metal contamination was most severe in the central–eastern region of the study area, with a ring-shaped distribution, which correlated with the presence of zinc smelting and chemical plants. Furthermore, the study revealed that soil heavy metal contamination posed a health threat to the local population, with children being particularly vulnerable to non-carcinogenic risks when the HI was 1.21 and to potential carcinogenic risks when the CR was 2.27 × 10−5. Additionally, heavy metal pollution caused a moderate to high ecological risk in 56.4% of the samples. The results highlighted the severe impact of soil heavy metal pollution on the delicate ecosystem of the Upper Yellow River and Qinghai–Tibet Plateau. The government should take action to improve soil environment management and prevent heavy metal pollution to protect the health of the local population and the ecological environment.

Assessment of heavy metal pollution and preschool children health risk in urban street dusts from different functional areas in a typical industrial and mining city, NW China.

To assess the pollution characteristics and health risks associated with street dust exposure among preschool children in typical industrial and mining areas, we analyzed heavy metal concentrations of 20 urban street dusts in commercial area (CA), residential area (RA), scientific and educational area (SEA) and industrial and mining area (IMA) from Baiyin, NW China. The average concentrations of Cr, Mn, Ni, Cu, Zn, Cd, Pb, As and Hg were 614.96, 484.25, 1757.74, 6868.86, 893.19, 77.62, 1473.99, 15.01 and 0.59mg·kg-1, respectively. The ecological risk indexes for Cd, Cu and Hg were found as 20,075.20, 1425.07 and 1174.86, respectively, and the ecological risk was extremely high. The pollution load indexes (PLI) were > 1 for all four functional areas. The total hazard index (THI) for different functional areas were more than 1, and the main exposure pathway for children was ingestion route. Heavy metals in street dust of the IMA had the highest THI for children (43.88), and HI of Pb was being most significant (17.38). In addition, the carcinogenic risk to children via the respiratory route was acceptable. Furthermore, factor analysis and cluster analysis classified heavy metals into two groups, indicating common anthropogenic sources for Cr, Ni, Cu, Zn, Cd, Pb, As and Hg. In conclusion, urban street dusts from industrial and mining area of Baiyin, NW China were found polluted by heavy metals and the pollution would pose an obvious non-carcinogenic risk to preschool children.