Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an...Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.展开更多
In the Tano River Basin,groundwater serves as a crucial resource;however,its quantity and quality with regard to trace elements and microbiological loadings remain poorly understood due to the lack of groundwater logs...In the Tano River Basin,groundwater serves as a crucial resource;however,its quantity and quality with regard to trace elements and microbiological loadings remain poorly understood due to the lack of groundwater logs and limited water research.This study presents a comprehensive analysis of the Tano River Basin,focusing on three key objectives.First,it investigated the aquifer hydraulic parameters and the results showed significant spatial variations in borehole depths,yields,transmissivity,hydraulic conductivity,and specific capacity.Deeper boreholes were concentrated in the northeastern and southeastern zones,while geological formations,particu-larly the Apollonian Formation,exhibit a strong influence on borehole yields.The study identified areas with high transmissivity and hydraulic conductivity in the southern and eastern regions,suggesting good groundwater avail-ability and suitability for sustainable water supply.Sec-ondly,the research investigated the groundwater quality and observed that the majority of borehole samples fall within WHO(Guidelines for Drinking-water Quality,Environmental Health Criteria,Geneva,2011,2017.http://www.who.int)limit.However,some samples have pH levels below the standards,although the groundwater generally qualifies as freshwater.The study further explores hydrochemical facies and health risk assessment,highlighting the dominance of Ca–HCO3 water type.Trace element analysis reveals minimal health risks from most elements,with chromium(Cr)as the primary contributor to chronic health risk.Overall,this study has provided a key insights into the Tano River Basin’s hydrogeology and associated health risks.The outcome of this research has contributed to the broader understanding of hydrogeologi-cal dynamics and the importance of managing groundwater resources sustainably in complex geological environments.展开更多
This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed ...This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)<total carcinogenic risk ≤ 10^(-4)), with higher risks observed for children compared to adults. The relationship between TMs, their sources, and health risks indicated that urban and industrial sources were primarily associated with As, contributing to 75.1% of carcinogenic risks and 55.7% of non-carcinogenic risks, making them the primary control factors. Meanwhile, agricultural sources were primarily linked to Cd and Pb, contributing to 13.1% of carcinogenic risks and 21.8% of non-carcinogenic risks, designating them as secondary control factors.展开更多
Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the stu...Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound pollution.The root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dominated by Cd and Ni to varying degrees, especially wheat. As indicated by the health risk assessment results, the intake of maize in the study area does not pose significant human health risks;however, Cu has high risks to human health, and the compound heavy metal pollution caused by the intake of wheat in the study area poses risks to the health of both adults and children. Overall, the soils and crops in the study area suffer a high degree of heavy metal pollution, for which mining activities may be the main reason.展开更多
The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the less...The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin.展开更多
Chifeng is a concentrated mining area for non-ferrous metal minerals,as well as a key prevention and control area for heavyduty enterprises.This situation necessitates an efective ecological and human health risk asse...Chifeng is a concentrated mining area for non-ferrous metal minerals,as well as a key prevention and control area for heavyduty enterprises.This situation necessitates an efective ecological and human health risk assessment of heavy metal(loid)s driven by the wide distribution of metal ore processing,mining,and smelting factories in Hexigten Banner and Bairin Left Banner.We conducted surveys to assess the levels of heavy metal(loid)s(Cr,As,Pb,Cd,and Hg)in the topsoil and groundwater of the areas.The results indicated that the concentrations of As,Cd,and Pb in partial soil samples exceeded the environmental quality standards of Grade II.Based on contamination assessments,such as geoaccumulation indices and pollution indices,we inferred that Cd,Pb,and As were primary pollutants in topsoil.Potential ecological risks when considered as part of the average risk indices(RI)are up to 1626.40 and 2818.76,respectively,in the two areas.Comparative analysis revealed that Cd posed a very high potential ecological risk,followed by As.Moreover,the evaluation showed that the three exposure pathways of carcinogenic and non-carcinogenic risk followed a descending order:inhalation>ingestion>dermal contact,except for Pb.Arsenic in topsoil posed a potential non-carcinogenic risk to human health,while there were no adverse efects of As in groundwater.In addition,the average total carcinogenic risk for As in the two areas,as well as the risk of Pb in the topsoil of Bairin Left Banner and all the fve heavy metal(loid)s in groundwater,exceeded human tolerance.Pb–Zn mines caused higher human health risks.In addition,the tandem contamination of heavy metal(loid)s in soil and groundwater was not obvious.This research study provides a basis for pollution remediation to control heavy industry-induced ecological and health risks of heavy metal(loid)s.展开更多
Global ecosystems and public health have been greatly impacted by the accumulation of heavy metal(loid)s in water.Source-specific risk apportionment is needed to prevent and manage potential groundwater contamination ...Global ecosystems and public health have been greatly impacted by the accumulation of heavy metal(loid)s in water.Source-specific risk apportionment is needed to prevent and manage potential groundwater contamination with heavy metal(loid)s.The heavy metal(loid)s contamination status,water quality,ecological risk,and health risk apportionment of the Shule River Basin groundwater are poorly understood.Therefore,field sampling was performed to explore the water quality and risk of heavy metal(loid)s in the groundwater of the Shule River Basin in northwestern China.A total of 96 samples were collected from the study area to acquire data for water quality and heavy metal(loid)s risk.There was noticeable accumulation of ferrum in the groundwater of the Shule River Basin.The levels of pollution were considered to be moderately low,as evaluated by the degree of contamination,heavy metal evaluation index,heavy metal pollution index,and Nemerow pollution index.The ecological risks were also low.However,an assessment of the water quality index revealed that only 58.34%of the groundwater samples had good water quality.The absolute principal component scores-multiple linear regression model was more suited for this study area than the positive matrix factorization model.There were no obvious noncarcinogenic or carcinogenic concerns for all types of receptors according to the values of the total hazard index and total carcinogenic risk.The human activities and the initial geological environment factor(65.85%)was the major source of noncarcinogenic risk(residential children:87.56%;residential adults:87.52%;recreational children:86.77%;and recreational adults:85.42%),while the industrial activity factor(16.36%)was the major source of carcinogenic risk(residential receptors:87.96%;and recreational receptors:68.73%).These findings provide fundamental and crucial information for reducing the health issues caused by heavy metal(loid)s contamination of groundwater in arid areas.展开更多
This study investigated the groundwater quality and health risks associated with informal e-waste processing in the Alaba International Market in Lagos, Nigeria. Twenty-two groundwater samples were collected from hand...This study investigated the groundwater quality and health risks associated with informal e-waste processing in the Alaba International Market in Lagos, Nigeria. Twenty-two groundwater samples were collected from hand-dug wells in the market area and analyzed for physicochemical properties and heavy metal concentrations. The results showed that the groundwater quality was poor, with high levels of heavy metals, including cadmium, lead, and chromium. The health index (HI) for children and adults was above the tolerable threshold levels, indicating a potential health risk to the population. Principal component analysis and hierarchical cluster analysis were used to identify the sources of metals in groundwater, and the results showed that informal e-waste processing was a significant source of contamination. The study highlights the need for effective management strategies to mitigate the potential health risks associated with informal e-waste processing and ensure public health and environmental safety.展开更多
The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were eval...The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were evaluated by calculating geo-accumulation(I_(geo)) and summary pollution(Z_c) indices.Potential human health risk was assessed using the United States Environmental Protection agency's human health risk assessment model.The results show that mean contents of all elements tested except Ni and Cr were substantially higher than local geochemical background values.According to the I_(geo),Yerevan territory is strongly-to-extremely polluted by As,Ag,Hg,Mo,and Cd.The Z_c assessment indicated that very high pollution was detected in 36%of samples,high in 32%,average in 12%,and low in 20%.The health risk assessment revealed a noncarcinogenic risk(HI >1) for children at 13 samplings sites and for adults at one sampling site.For children the risk was due to elevated levels of Mo,Cd,Co,and As,while for adults,only Mo.Carcinogenic risk(>1:1,000,000) of As and Cr via ingestion pathway was observed in 25 and 14 samples,respectively.This study,therefore,is the base for further detailed investigations to organize problematic site remediation and risk reduction measures.展开更多
Objective This study was designed to conduct a retrospective and systematic occupational health risk assessment(OHRA)of enterprises that used benzene,toluene,and xylene(BTX)in Shanghai,China.Methods All data for the s...Objective This study was designed to conduct a retrospective and systematic occupational health risk assessment(OHRA)of enterprises that used benzene,toluene,and xylene(BTX)in Shanghai,China.Methods All data for the study were obtained from 1,705 occupational health examination and evaluation reports from 2013 to 2017,and a semiquantitative model following Chinese OHRA guidelines(GBZ/T 298-2017)was applied for the assessment.Results The selected enterprises using BTX were mainly involved in manufacturing of products.Using the exposure level method,health risk levels associated with exposure to BTX were classified as medium,negligible,or low.However,the risk levels associated with benzene and toluene were significantly different according to job types,with gluers and inkers exhibiting greater health risks.For the same job type,the health risk levels assessed using the comprehensive index method were higher than those using the exposure level method.Conclusion Our OHRA reveals that workers who are exposed to BTX still face excessive health risk.Additionally,the risk level varied depending on job categories and exposure to specific chemicals.Therefore,additional control measures recommended by OHRA guidelines are essential to reduce worker exposure levels.展开更多
This study investigates the values of pH,total dissolved solids(TDS),elevation,oxidative reduction potential(ORP),temperature,and depth,while the concentrations of Br,and potentially harmful metals(PHMs)such as Cr,Ni,...This study investigates the values of pH,total dissolved solids(TDS),elevation,oxidative reduction potential(ORP),temperature,and depth,while the concentrations of Br,and potentially harmful metals(PHMs)such as Cr,Ni,Cd,Mn,Cu,Pb,Co,Zn,and Fe in the groundwater samples.Moreover,geographic information system(GIS),XLSTAT,and IBM SPSS Statistics 20 software were used for spatial distribution modeling,principal component analysis(PCA),cluster analysis(CA),and Quantile-Quantile(Q-Q)plotting to determine groundwater pollution sources,similarity index,and normal distribution reference line for the selected parameters.The mean values of pH,TDS,elevation,ORP,temperature,depth,and Br were 7.2,322 mg/L,364 m,188 mV,29.6℃,70 m,0.20 mg/L,and PHMs like Cr,Ni,Cd,Mn,Cu,Pb,Co,Zn,and Fe were 0.38,0.26,0.08,0.27,0.36,0.22,0.04,0.43 and 0.86 mg/L,respectively.PHMs including Cr(89%),Cd(43%),Mn(23%),Pb(79%),Co(20%),and Fe(91%)exceeded the guideline values set by the world health organization(WHO).The significant R^(2)values of PCA for selected parameters were also determined(0.62,0.67,0.78,0.73,0.60,0.87,-0.50,0.69,0.70,0.74,-0.50,0.70,0.67,0.79,0.59,and-0.55,respectively).PCA revealed three geochemical processes such as geogenic,anthropogenic,and reducing conditions.The mineral phases of Cd(OH)_(2),Fe(OH)_(3),FeOOH,Mn_(3)O_(4),Fe_(2)O_(3),MnOOH,Pb(OH)_(2),Mn(OH)_(2),MnO_(2),and Zn(OH)_(2)(-3.7,3.75,9.7,-5.8,8.9,-3.6,2.2,-4.6,-7.7,-0.9,and 0.003,respectively)showed super-saturation and under-saturation conditions.Health risk assessment(HRA)values for PHMs were also calculated and the values of hazard quotient(HQ),and hazard indices(HI)for the entire study area were increased in the following order:Cd>Ni>Cu>Pb>Mn>Zn>Cr.Relatively higher HQ and HI values of Ni,Cd,Pb,and Cu were greater than one showing unsuitability of groundwater for domestic,agriculture,and drinking purposes.The long-term ingestion of groundwater could also cause severe health concerns such as kidney,brain dysfunction,liver,stomach problems,and even cancer.展开更多
Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populat...Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populations,particularly for pneumonia.Methods We developed a method to evaluate risks from airborne microorganisms,guided by the principle that closer evolutionary relationships reflect similar biological characteristics,and thus used16 S rDNA sequences of 10 common pneumonia-related bacterial pathogens.We calculated a risk of breath-related(Rbr)index of airborne bacterial communities and verified effectiveness with artificial flora and a clinical project.Results We suggested applying Rbr80 to evaluate the health risks of airborne bacterial communities that comprise 80% of dominant operational taxonomic units(OTUs).The feasibility of Rbr80 was confirmed by artificial flora and by pneumonia data from a hospital.A high Rbr80 value indicated a high risk of pneumonia from airborne bacterial communities.Conclusion Rbr80 is an effective index to evaluate the pneumonia-associated risk from airborne bacteria.Values of Rbr80 greater than 15.40 are considered high risk.展开更多
Polycyclic aromatic hydrocarbons(PAHs)in indoor dust are one of the common exposure sources for children worldwide.The aim of this study is to explore PAHs pollution status in indoor dust and estimate health risk on C...Polycyclic aromatic hydrocarbons(PAHs)in indoor dust are one of the common exposure sources for children worldwide.The aim of this study is to explore PAHs pollution status in indoor dust and estimate health risk on Chinese children with big data.Weighted average concentration was used to analyze source and characterization of PAHs in indoor dust based on peer=reviewed literature.According to specific inclusion crteria,17 studies were included finally to analyze weighted average concentration.The national average concentration of ∑_(16)PAHs was approximately 25.696 ug/g.The highest concentration of ∑_(16)AHs was in Shanxi(2111.667 ug/g),and the lowest was in Hong Kong(1.505 μg/g).The concentrations in Shanxi and Guangdong were higher than national level and the over standard rate was 18.18%.The concentrations of individual PAHs varied greatly across the country,and Flu in Shanxi was the highest(189.400 μg/g).The sources of PAHs varied in different regions and combustion processes played a leading role.PAHs exposure through ingestion and dermal contact was more carcinogenic than inhalation.The incremental lifetime cancer risk model indicated that children lived in Shanxi were found in the highest health risk coupled with the highest BaPE concentration(54.074μg/g).Although PAHs concentrations of indoor dust showed a downward trend from 2005 to 2018,indoor environmental sanitation should be improved with multidisciplinary efforts.Health standard should be possibly established to minimize children exposure to PAHs in indoor dust in China.展开更多
In this study, the concentration and spatial distribution of potentially toxic metals(PTMs), including arsenic(As), cadmium(Cd), chromium(Cr), lead(Pb), copper(Cu), iron(Fe), manganese(Mn), and magnesium(Mg) in 23 wel...In this study, the concentration and spatial distribution of potentially toxic metals(PTMs), including arsenic(As), cadmium(Cd), chromium(Cr), lead(Pb), copper(Cu), iron(Fe), manganese(Mn), and magnesium(Mg) in 23 wells and drinking groundwater distribution networks of Rafsanjan, located in southeast Iran were evaluated. Moreover, the assessment of carcinogenic and non-carcinogenic risks was estimated by Monte Carlo simulation(MCS). The results showed that the concentrations of As and Pb in more than 99% and 23.46% of the study area, respectively, were higher than the maximum concentration level(10 μg/L). The mean concentration of other metals, including Cd, Cr, Cu, Fe, Mg, and Mn in all drinking water resources was within the WHO standard level. The mean hazard quotient(HQ) for As in the age group of children was 9.246 and adults 2.972, indicating high non-carcinogenic risk of As in the study area. The lifetime cancer risk(LTCR) of As was 1.36 E-3 for adults and 1.52 E-2 for children, indicating high non-carcinogenic risk of As. The level of HQ and LTCR for Pb in both age groups was in the acceptable range. The results of sensitivity analysis showed that the most effective variables were pollutant concentration and body weight(BW), respectively. Finally, it can be concluded that exposure to PTMs, especially As through drinking water in the study area can have significant effects on people’s health living in the area;therefore, it is necessary to treat and remove As from groundwater resources before drinking or using for domestic purpose.展开更多
The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area,and carry out a corresponding health risk assessment for the local populace.To do t...The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area,and carry out a corresponding health risk assessment for the local populace.To do this,34 shallow groundwater(SG)samples and 18 mid-layer groundwater(MG)samples were collected from the Sulin mining area.To minimize the uncertainties in the health risk assessment,this paper relied on Monte Carlo simulations and sensitivity analysis.The results revealed that Sr and Mn contents exceeded their corresponding WHO(Guidelines for drinking water quality,4th edn.Geneva,2011)guidelines and Chinese groundwater standards(GB/T14848-2017),while the other analyzed trace elements remain below those threshold values.The calculated hazard quotient and hazard index values for adults from ingestion exposure to SG and MG were well below the threshold limit of 1.Probabilistic simulations further show that the total cancer risk value above the limit of 1×10^(-6) is 0%for SG and 29.39%for MG.Sensitivity analysis identified the Sr and Cr contents as the most relevant element variables affecting the probabilistic non-carcinogenic and carcinogenic risk values in the model,respectively.展开更多
The aim of this study was to evaluate groundwater fitness for domestic and irrigational use in Unnao district of Uttar Pradesh,India.For this study,block wise(n=16)groundwater samples were collected,and measured param...The aim of this study was to evaluate groundwater fitness for domestic and irrigational use in Unnao district of Uttar Pradesh,India.For this study,block wise(n=16)groundwater samples were collected,and measured parameters were analyzed using the pollution index of groundwater(PIG),various irrigational indices,and graphical techniques.The results of this study suggested that most of the parameters were within the prescribed limits of WHO and BIS,excluding F-(0.4 to 2.6 mg L^(-1))and Fe^(2+)(0.1 to 1.7 mg L^(-1)).Concentrations of total dissolved solids(TDS)were exceeded the desirable limit(>500 mg L^(-1))in 43.75%of samples at some sites.The Gibbs plot revealed that groundwater chemistry was governed by rock-water interaction in the region,especially silicate weathering.The Piper plot suggested that Ca^(2+)-HCO3-is dominant hydrochemical facies in the area followed by mixed Ca^(2+)-Na^(+)-HCO_(3)^(-)type,Na^(+)-Cl^(-)type,and Na^(+)-HCO_(3)^(-)type.PIG evaluation revealed that the contribution of F-and Fe2+in groundwater degradation is high in comparison to other elements in the region,about 18.75%samples showed low pollution,while about 6.25%samples shows moderate pollution,and 6.25%samples reflected high pollution.The human health risk(HHR)assessment finding suggested that children(mean:1.36)are more vulnerable than adults(mean:1.01).Sodium absorption ration(SAR),Residual sodium carbonate(RSC),and Permeability index(PI)indicated that most of the groundwater was suitable for irrigation,whereas,Magnesium hazard ration(MHR)and Potential salinity(PS)indices suggested that only 37.5%and 56.25%of the samples were suitable for irrigational use,respectively.This regional study would help in decision making for stakeholders and relevant authorities in the execution of groundwater management and remediation plans in the area.展开更多
Water contamination by chemical pollutants is increasingly associated with waterborne diseases worldwide. The objective of this study is to assess the chemical health risk associated with drinking water consumption in...Water contamination by chemical pollutants is increasingly associated with waterborne diseases worldwide. The objective of this study is to assess the chemical health risk associated with drinking water consumption in Dakar, Senegal. The methodology adopted in this study is based on the determination of trace metals (Cd, Pb, Fe, Cu and Mn) in human drinking water by flame atomic absorption spectrometry, the estimation of the exposure of populations of the study area on the basis of the quantity of water consumed daily and the determination of the hazard quotient which allows estimating the health risk. The results indicate unacceptable levels of Pb and Cd in the water according to World Health Organization (WHO) guidelines, while the concentrations of Fe, Cu and Mn are below the regulatory values. The hazard quotient (HQ) is in the majority of samples higher than 1 in children and infants for scenario 1 (based on WHO data), reflecting a high risk for this target. In scenario 2 based on consumption data from the populations studied, the HQ is greater than 1 only in heavy consumers. The drinking water consumed by Dakar population presents health risks related to Pb and Cd, particularly for infants, children and heavy consumers, hence the need to strengthen the water treatment system before home consumption.展开更多
This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the followi...This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.展开更多
Samples of borehole water were randomly collected from twenty households in the Lagos-Ogun axis of southwestern Nigeria. The samples were analyzed for silver, iron, manganese, lead, nickel, magnesium, cadmium, zinc, s...Samples of borehole water were randomly collected from twenty households in the Lagos-Ogun axis of southwestern Nigeria. The samples were analyzed for silver, iron, manganese, lead, nickel, magnesium, cadmium, zinc, sodium, potassium, pH, turbidity, dissolved oxygen, electrical conductivity, alkalinity, total hardness, chloride, nitrate and sulphate following standard methods of water analysis. Results obtained were compared with global background values and WHO guidelines for drinking water. The pH values ranged from 4.17 ± 0.26 to 6.07 ± 0.27 while the metal pollution indexes are between 0.01 and 0.11. Cadmium, manganese, iron and nitrate (mg/L) levels were found to be relatively high in most of the water samples. Results obtained were analyzed statistically. Health risk assessment for exposure to cancer and non-cancer indices was evaluated. Kempster and co-workers classification of drinking water quality was applied;nineteen of the twenty household water samples were found to fall short of the ideal water quality suitable for lifetime use.展开更多
In the department of Zouan-Hounien, gold mining is booming. This activity, marked by the excavation of rocks and the use of chemicals such as mercury, is likely to contaminate the region’s groundwater resources and e...In the department of Zouan-Hounien, gold mining is booming. This activity, marked by the excavation of rocks and the use of chemicals such as mercury, is likely to contaminate the region’s groundwater resources and expose populations to serious diseases. This study aims to assess the health risks associated with the consumption of this water by the population. To this end, 72 groundwater samples were taken in eight (08) villages of the department at the rate of forty-six (46) well water samples and twenty-six (26) borehole water samples. A total of twenty-twenty-three wells and thirteen boreholes were sampled during two campaigns. An atomic absorption spectrometer (AAS) was used to determine the concentrations of metallic trace elements (MTEs), such as mercury (Hg), lead (Pb), cadmium (Cd), Arsenic (As), and iron (Fe) in the different samples. The daily exposure doses for oral ingestion (CDIing) and skin contact (Expderm) were calculated. The non-carcinogenic (HQ) and carcinogenic risks (CR) were estimated. The results show that the mean concentrations of Fe, Pb, Hg, As and Cd are respectively 2233.48 > 3.10 > 0.60 > 1.18 > 0.08 μg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>L<sup>-1</sup> in the wells and 2427.94 > 4.08 > 1.27 > 1.76 > 0.08 μg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>L<sup>-1</sup> in boreholes. Evaluating the risks to human health reveals that the mean values of hazard quotient (HQ) and cancer risk (CR) for all the elements in the wells and boreholes are lower than 1 and 10<sup>-4</sup> respectively in children and adults for oral and dermal exposure. However, at the oral exposure level, 9 wells and 6 boreholes recorded HQ and CR above the define<span>d critical limits. These values indicate that the occurrence of non-cancero</span>us and cancerous diseases in populations consuming these waters by contamination with mercury and arsenic is not excluded. Dermal exposure to MTEs also poses no potential health risk to the population.展开更多
基金supported by the project of China Geological Survey(Grant No.DD20221677-2)the fundamental research funds of Chinese Academy of Geological Sciences Basal Research Fund(Grant No.JKYQN202307).
文摘Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.
文摘In the Tano River Basin,groundwater serves as a crucial resource;however,its quantity and quality with regard to trace elements and microbiological loadings remain poorly understood due to the lack of groundwater logs and limited water research.This study presents a comprehensive analysis of the Tano River Basin,focusing on three key objectives.First,it investigated the aquifer hydraulic parameters and the results showed significant spatial variations in borehole depths,yields,transmissivity,hydraulic conductivity,and specific capacity.Deeper boreholes were concentrated in the northeastern and southeastern zones,while geological formations,particu-larly the Apollonian Formation,exhibit a strong influence on borehole yields.The study identified areas with high transmissivity and hydraulic conductivity in the southern and eastern regions,suggesting good groundwater avail-ability and suitability for sustainable water supply.Sec-ondly,the research investigated the groundwater quality and observed that the majority of borehole samples fall within WHO(Guidelines for Drinking-water Quality,Environmental Health Criteria,Geneva,2011,2017.http://www.who.int)limit.However,some samples have pH levels below the standards,although the groundwater generally qualifies as freshwater.The study further explores hydrochemical facies and health risk assessment,highlighting the dominance of Ca–HCO3 water type.Trace element analysis reveals minimal health risks from most elements,with chromium(Cr)as the primary contributor to chronic health risk.Overall,this study has provided a key insights into the Tano River Basin’s hydrogeology and associated health risks.The outcome of this research has contributed to the broader understanding of hydrogeologi-cal dynamics and the importance of managing groundwater resources sustainably in complex geological environments.
基金supported by Project of Chongqing Science and Technology Bureau (cstc2022jxjl0005)。
文摘This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)<total carcinogenic risk ≤ 10^(-4)), with higher risks observed for children compared to adults. The relationship between TMs, their sources, and health risks indicated that urban and industrial sources were primarily associated with As, contributing to 75.1% of carcinogenic risks and 55.7% of non-carcinogenic risks, making them the primary control factors. Meanwhile, agricultural sources were primarily linked to Cd and Pb, contributing to 13.1% of carcinogenic risks and 21.8% of non-carcinogenic risks, designating them as secondary control factors.
基金jointly funded by National Natural Science Foundation of China (41877398)project of the China Geological Survey (DD20221773)。
文摘Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound pollution.The root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dominated by Cd and Ni to varying degrees, especially wheat. As indicated by the health risk assessment results, the intake of maize in the study area does not pose significant human health risks;however, Cu has high risks to human health, and the compound heavy metal pollution caused by the intake of wheat in the study area poses risks to the health of both adults and children. Overall, the soils and crops in the study area suffer a high degree of heavy metal pollution, for which mining activities may be the main reason.
文摘The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin.
基金the National Natural Science Foundation of China(No.42072284,No.42027801,No.41877186)the National Key R&D Program of China(2021YFC2902004)+1 种基金the Major Science and Technology Projects of Inner Mongolia Autonomous Region(2020ZD0020-4)the Fundamental Research Funds for the Central Universities(2022YQSH01,2020YJSSH01,2021YJSSH01)。
文摘Chifeng is a concentrated mining area for non-ferrous metal minerals,as well as a key prevention and control area for heavyduty enterprises.This situation necessitates an efective ecological and human health risk assessment of heavy metal(loid)s driven by the wide distribution of metal ore processing,mining,and smelting factories in Hexigten Banner and Bairin Left Banner.We conducted surveys to assess the levels of heavy metal(loid)s(Cr,As,Pb,Cd,and Hg)in the topsoil and groundwater of the areas.The results indicated that the concentrations of As,Cd,and Pb in partial soil samples exceeded the environmental quality standards of Grade II.Based on contamination assessments,such as geoaccumulation indices and pollution indices,we inferred that Cd,Pb,and As were primary pollutants in topsoil.Potential ecological risks when considered as part of the average risk indices(RI)are up to 1626.40 and 2818.76,respectively,in the two areas.Comparative analysis revealed that Cd posed a very high potential ecological risk,followed by As.Moreover,the evaluation showed that the three exposure pathways of carcinogenic and non-carcinogenic risk followed a descending order:inhalation>ingestion>dermal contact,except for Pb.Arsenic in topsoil posed a potential non-carcinogenic risk to human health,while there were no adverse efects of As in groundwater.In addition,the average total carcinogenic risk for As in the two areas,as well as the risk of Pb in the topsoil of Bairin Left Banner and all the fve heavy metal(loid)s in groundwater,exceeded human tolerance.Pb–Zn mines caused higher human health risks.In addition,the tandem contamination of heavy metal(loid)s in soil and groundwater was not obvious.This research study provides a basis for pollution remediation to control heavy industry-induced ecological and health risks of heavy metal(loid)s.
基金This work was supported by the Kunlun Talent Action Plan of Qinghai Province(E140 WX42)National Natural Science Foundation of China(52179026)Strategy for Water Resource Security in Yellow River Sources。
文摘Global ecosystems and public health have been greatly impacted by the accumulation of heavy metal(loid)s in water.Source-specific risk apportionment is needed to prevent and manage potential groundwater contamination with heavy metal(loid)s.The heavy metal(loid)s contamination status,water quality,ecological risk,and health risk apportionment of the Shule River Basin groundwater are poorly understood.Therefore,field sampling was performed to explore the water quality and risk of heavy metal(loid)s in the groundwater of the Shule River Basin in northwestern China.A total of 96 samples were collected from the study area to acquire data for water quality and heavy metal(loid)s risk.There was noticeable accumulation of ferrum in the groundwater of the Shule River Basin.The levels of pollution were considered to be moderately low,as evaluated by the degree of contamination,heavy metal evaluation index,heavy metal pollution index,and Nemerow pollution index.The ecological risks were also low.However,an assessment of the water quality index revealed that only 58.34%of the groundwater samples had good water quality.The absolute principal component scores-multiple linear regression model was more suited for this study area than the positive matrix factorization model.There were no obvious noncarcinogenic or carcinogenic concerns for all types of receptors according to the values of the total hazard index and total carcinogenic risk.The human activities and the initial geological environment factor(65.85%)was the major source of noncarcinogenic risk(residential children:87.56%;residential adults:87.52%;recreational children:86.77%;and recreational adults:85.42%),while the industrial activity factor(16.36%)was the major source of carcinogenic risk(residential receptors:87.96%;and recreational receptors:68.73%).These findings provide fundamental and crucial information for reducing the health issues caused by heavy metal(loid)s contamination of groundwater in arid areas.
文摘This study investigated the groundwater quality and health risks associated with informal e-waste processing in the Alaba International Market in Lagos, Nigeria. Twenty-two groundwater samples were collected from hand-dug wells in the market area and analyzed for physicochemical properties and heavy metal concentrations. The results showed that the groundwater quality was poor, with high levels of heavy metals, including cadmium, lead, and chromium. The health index (HI) for children and adults was above the tolerable threshold levels, indicating a potential health risk to the population. Principal component analysis and hierarchical cluster analysis were used to identify the sources of metals in groundwater, and the results showed that informal e-waste processing was a significant source of contamination. The study highlights the need for effective management strategies to mitigate the potential health risks associated with informal e-waste processing and ensure public health and environmental safety.
基金implemented in the frames of a theme "Studying geochemical stream of elements in atmospheric air of Yerevan"(No 13-1E220,2011) under agreement-based(thematic) financial support of the State Committee of Science to the Ministry of Education and Sciences RA
文摘The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were evaluated by calculating geo-accumulation(I_(geo)) and summary pollution(Z_c) indices.Potential human health risk was assessed using the United States Environmental Protection agency's human health risk assessment model.The results show that mean contents of all elements tested except Ni and Cr were substantially higher than local geochemical background values.According to the I_(geo),Yerevan territory is strongly-to-extremely polluted by As,Ag,Hg,Mo,and Cd.The Z_c assessment indicated that very high pollution was detected in 36%of samples,high in 32%,average in 12%,and low in 20%.The health risk assessment revealed a noncarcinogenic risk(HI >1) for children at 13 samplings sites and for adults at one sampling site.For children the risk was due to elevated levels of Mo,Cd,Co,and As,while for adults,only Mo.Carcinogenic risk(>1:1,000,000) of As and Cr via ingestion pathway was observed in 25 and 14 samples,respectively.This study,therefore,is the base for further detailed investigations to organize problematic site remediation and risk reduction measures.
基金supported by research grants from the National Natural Science Foundation of China[No.81474929]。
文摘Objective This study was designed to conduct a retrospective and systematic occupational health risk assessment(OHRA)of enterprises that used benzene,toluene,and xylene(BTX)in Shanghai,China.Methods All data for the study were obtained from 1,705 occupational health examination and evaluation reports from 2013 to 2017,and a semiquantitative model following Chinese OHRA guidelines(GBZ/T 298-2017)was applied for the assessment.Results The selected enterprises using BTX were mainly involved in manufacturing of products.Using the exposure level method,health risk levels associated with exposure to BTX were classified as medium,negligible,or low.However,the risk levels associated with benzene and toluene were significantly different according to job types,with gluers and inkers exhibiting greater health risks.For the same job type,the health risk levels assessed using the comprehensive index method were higher than those using the exposure level method.Conclusion Our OHRA reveals that workers who are exposed to BTX still face excessive health risk.Additionally,the risk level varied depending on job categories and exposure to specific chemicals.Therefore,additional control measures recommended by OHRA guidelines are essential to reduce worker exposure levels.
基金financially supported National Natural Science Foundation of China(Grant Nos.41521001 and 41877204)the 111 Program(State Administration Foreign Experts Affairs&the Ministry of Education of China,Grant No.B18049)the China Postdoctoral Science Foundation(Grant No.2018M642944)。
文摘This study investigates the values of pH,total dissolved solids(TDS),elevation,oxidative reduction potential(ORP),temperature,and depth,while the concentrations of Br,and potentially harmful metals(PHMs)such as Cr,Ni,Cd,Mn,Cu,Pb,Co,Zn,and Fe in the groundwater samples.Moreover,geographic information system(GIS),XLSTAT,and IBM SPSS Statistics 20 software were used for spatial distribution modeling,principal component analysis(PCA),cluster analysis(CA),and Quantile-Quantile(Q-Q)plotting to determine groundwater pollution sources,similarity index,and normal distribution reference line for the selected parameters.The mean values of pH,TDS,elevation,ORP,temperature,depth,and Br were 7.2,322 mg/L,364 m,188 mV,29.6℃,70 m,0.20 mg/L,and PHMs like Cr,Ni,Cd,Mn,Cu,Pb,Co,Zn,and Fe were 0.38,0.26,0.08,0.27,0.36,0.22,0.04,0.43 and 0.86 mg/L,respectively.PHMs including Cr(89%),Cd(43%),Mn(23%),Pb(79%),Co(20%),and Fe(91%)exceeded the guideline values set by the world health organization(WHO).The significant R^(2)values of PCA for selected parameters were also determined(0.62,0.67,0.78,0.73,0.60,0.87,-0.50,0.69,0.70,0.74,-0.50,0.70,0.67,0.79,0.59,and-0.55,respectively).PCA revealed three geochemical processes such as geogenic,anthropogenic,and reducing conditions.The mineral phases of Cd(OH)_(2),Fe(OH)_(3),FeOOH,Mn_(3)O_(4),Fe_(2)O_(3),MnOOH,Pb(OH)_(2),Mn(OH)_(2),MnO_(2),and Zn(OH)_(2)(-3.7,3.75,9.7,-5.8,8.9,-3.6,2.2,-4.6,-7.7,-0.9,and 0.003,respectively)showed super-saturation and under-saturation conditions.Health risk assessment(HRA)values for PHMs were also calculated and the values of hazard quotient(HQ),and hazard indices(HI)for the entire study area were increased in the following order:Cd>Ni>Cu>Pb>Mn>Zn>Cr.Relatively higher HQ and HI values of Ni,Cd,Pb,and Cu were greater than one showing unsuitability of groundwater for domestic,agriculture,and drinking purposes.The long-term ingestion of groundwater could also cause severe health concerns such as kidney,brain dysfunction,liver,stomach problems,and even cancer.
基金supported by the CAMS Innovation Fund for Medical Science[CIFMS,2018-I2M-1-001]the National Key R&D Program of China[2017YFC0702800]+1 种基金the National Natural Science Foundation of China[82070103]the Central Public-interest Scientific Institution Basal Research Fund[2016ZX310037]。
文摘Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populations,particularly for pneumonia.Methods We developed a method to evaluate risks from airborne microorganisms,guided by the principle that closer evolutionary relationships reflect similar biological characteristics,and thus used16 S rDNA sequences of 10 common pneumonia-related bacterial pathogens.We calculated a risk of breath-related(Rbr)index of airborne bacterial communities and verified effectiveness with artificial flora and a clinical project.Results We suggested applying Rbr80 to evaluate the health risks of airborne bacterial communities that comprise 80% of dominant operational taxonomic units(OTUs).The feasibility of Rbr80 was confirmed by artificial flora and by pneumonia data from a hospital.A high Rbr80 value indicated a high risk of pneumonia from airborne bacterial communities.Conclusion Rbr80 is an effective index to evaluate the pneumonia-associated risk from airborne bacteria.Values of Rbr80 greater than 15.40 are considered high risk.
基金supported by the National Natural Science Foundation of China(No.21976169)the Natural Science Foundation of Beijing,China(No.8182055)the Opening Fund of State Key Laboratory of Building Safety and Built Environment,China(No.BSBE2017-09)。
文摘Polycyclic aromatic hydrocarbons(PAHs)in indoor dust are one of the common exposure sources for children worldwide.The aim of this study is to explore PAHs pollution status in indoor dust and estimate health risk on Chinese children with big data.Weighted average concentration was used to analyze source and characterization of PAHs in indoor dust based on peer=reviewed literature.According to specific inclusion crteria,17 studies were included finally to analyze weighted average concentration.The national average concentration of ∑_(16)PAHs was approximately 25.696 ug/g.The highest concentration of ∑_(16)AHs was in Shanxi(2111.667 ug/g),and the lowest was in Hong Kong(1.505 μg/g).The concentrations in Shanxi and Guangdong were higher than national level and the over standard rate was 18.18%.The concentrations of individual PAHs varied greatly across the country,and Flu in Shanxi was the highest(189.400 μg/g).The sources of PAHs varied in different regions and combustion processes played a leading role.PAHs exposure through ingestion and dermal contact was more carcinogenic than inhalation.The incremental lifetime cancer risk model indicated that children lived in Shanxi were found in the highest health risk coupled with the highest BaPE concentration(54.074μg/g).Although PAHs concentrations of indoor dust showed a downward trend from 2005 to 2018,indoor environmental sanitation should be improved with multidisciplinary efforts.Health standard should be possibly established to minimize children exposure to PAHs in indoor dust in China.
基金the result of a research project with code 97361 approved by the Workplace Research Center of Rafsanjan University of Medical Sciences with the ethics code IR.RUMS.REC.1398.021 from the Vice Chancellor for Research of Rafsanjan University of Medical Sciencesowed to Rafsanjan University of Medical Sciences for its supports。
文摘In this study, the concentration and spatial distribution of potentially toxic metals(PTMs), including arsenic(As), cadmium(Cd), chromium(Cr), lead(Pb), copper(Cu), iron(Fe), manganese(Mn), and magnesium(Mg) in 23 wells and drinking groundwater distribution networks of Rafsanjan, located in southeast Iran were evaluated. Moreover, the assessment of carcinogenic and non-carcinogenic risks was estimated by Monte Carlo simulation(MCS). The results showed that the concentrations of As and Pb in more than 99% and 23.46% of the study area, respectively, were higher than the maximum concentration level(10 μg/L). The mean concentration of other metals, including Cd, Cr, Cu, Fe, Mg, and Mn in all drinking water resources was within the WHO standard level. The mean hazard quotient(HQ) for As in the age group of children was 9.246 and adults 2.972, indicating high non-carcinogenic risk of As in the study area. The lifetime cancer risk(LTCR) of As was 1.36 E-3 for adults and 1.52 E-2 for children, indicating high non-carcinogenic risk of As. The level of HQ and LTCR for Pb in both age groups was in the acceptable range. The results of sensitivity analysis showed that the most effective variables were pollutant concentration and body weight(BW), respectively. Finally, it can be concluded that exposure to PTMs, especially As through drinking water in the study area can have significant effects on people’s health living in the area;therefore, it is necessary to treat and remove As from groundwater resources before drinking or using for domestic purpose.
基金The authors sincerely thank the manuscript handling editors and reviewers for their insightful comments that helped to greatly improve this paper.This study was financially supported by the National Natural Science Foundation of China(41773100)the Natural Science Foundation of Anhui Province(2008085QD192)+5 种基金the Key Project of Excellent Talents support program in colleges and universities(gxyqZD2020048)a doctoral research initiation fund Project(2020BS010)a postdoctoral research initiation fund project(2021BSH001)the fourth batch of excellent academic and technical backbone Projects of Suzhou University(2020XJGG02)the Research Project of Wanbei Coal-Electricity Group Co.Ltd.(2020)and the Project for research activities of academic and technological leaders of Anhui Province(2020D239).
文摘The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area,and carry out a corresponding health risk assessment for the local populace.To do this,34 shallow groundwater(SG)samples and 18 mid-layer groundwater(MG)samples were collected from the Sulin mining area.To minimize the uncertainties in the health risk assessment,this paper relied on Monte Carlo simulations and sensitivity analysis.The results revealed that Sr and Mn contents exceeded their corresponding WHO(Guidelines for drinking water quality,4th edn.Geneva,2011)guidelines and Chinese groundwater standards(GB/T14848-2017),while the other analyzed trace elements remain below those threshold values.The calculated hazard quotient and hazard index values for adults from ingestion exposure to SG and MG were well below the threshold limit of 1.Probabilistic simulations further show that the total cancer risk value above the limit of 1×10^(-6) is 0%for SG and 29.39%for MG.Sensitivity analysis identified the Sr and Cr contents as the most relevant element variables affecting the probabilistic non-carcinogenic and carcinogenic risk values in the model,respectively.
文摘The aim of this study was to evaluate groundwater fitness for domestic and irrigational use in Unnao district of Uttar Pradesh,India.For this study,block wise(n=16)groundwater samples were collected,and measured parameters were analyzed using the pollution index of groundwater(PIG),various irrigational indices,and graphical techniques.The results of this study suggested that most of the parameters were within the prescribed limits of WHO and BIS,excluding F-(0.4 to 2.6 mg L^(-1))and Fe^(2+)(0.1 to 1.7 mg L^(-1)).Concentrations of total dissolved solids(TDS)were exceeded the desirable limit(>500 mg L^(-1))in 43.75%of samples at some sites.The Gibbs plot revealed that groundwater chemistry was governed by rock-water interaction in the region,especially silicate weathering.The Piper plot suggested that Ca^(2+)-HCO3-is dominant hydrochemical facies in the area followed by mixed Ca^(2+)-Na^(+)-HCO_(3)^(-)type,Na^(+)-Cl^(-)type,and Na^(+)-HCO_(3)^(-)type.PIG evaluation revealed that the contribution of F-and Fe2+in groundwater degradation is high in comparison to other elements in the region,about 18.75%samples showed low pollution,while about 6.25%samples shows moderate pollution,and 6.25%samples reflected high pollution.The human health risk(HHR)assessment finding suggested that children(mean:1.36)are more vulnerable than adults(mean:1.01).Sodium absorption ration(SAR),Residual sodium carbonate(RSC),and Permeability index(PI)indicated that most of the groundwater was suitable for irrigation,whereas,Magnesium hazard ration(MHR)and Potential salinity(PS)indices suggested that only 37.5%and 56.25%of the samples were suitable for irrigational use,respectively.This regional study would help in decision making for stakeholders and relevant authorities in the execution of groundwater management and remediation plans in the area.
文摘Water contamination by chemical pollutants is increasingly associated with waterborne diseases worldwide. The objective of this study is to assess the chemical health risk associated with drinking water consumption in Dakar, Senegal. The methodology adopted in this study is based on the determination of trace metals (Cd, Pb, Fe, Cu and Mn) in human drinking water by flame atomic absorption spectrometry, the estimation of the exposure of populations of the study area on the basis of the quantity of water consumed daily and the determination of the hazard quotient which allows estimating the health risk. The results indicate unacceptable levels of Pb and Cd in the water according to World Health Organization (WHO) guidelines, while the concentrations of Fe, Cu and Mn are below the regulatory values. The hazard quotient (HQ) is in the majority of samples higher than 1 in children and infants for scenario 1 (based on WHO data), reflecting a high risk for this target. In scenario 2 based on consumption data from the populations studied, the HQ is greater than 1 only in heavy consumers. The drinking water consumed by Dakar population presents health risks related to Pb and Cd, particularly for infants, children and heavy consumers, hence the need to strengthen the water treatment system before home consumption.
基金This study was funded by the survey projects initiated by the China Geological Survey(DD20189220,DD20211317,and 1212010634713).
文摘This study aims to investigate the mechanisms and health risks of fluoride enrichment in groundwater in the Loess Plateau,China.By taking Dali County,Shaanxi Province,China as an example,this study obtains the following results through field investigation and the analyses of water,soil,and crop samples.(1)The groundwater can be divided into two major types,namely the Quaternary pore-fissure water and Karst water.The Karst area and sandy area have high-quality groundwater and serve as the target areas for optional water supply.The groundwater in the study area is slightly alkaline and highly saline.Meanwhile,high-fluoride groundwater is mainly distributed in the loess and river alluvial plains in the depression area of the Guanzhong Basin and the discharge areas of the groundwater,with the highest fluoride concentration exceeding seven times the national standard.(2)Fluoride in groundwater mainly originates from a natural source and human activities.The natural source refers to the fluoride-bearing minerals in rocks and soil,and the fluoride from this source is mainly controlled by natural factors such as climate,geologic setting,pH,specific hydrochemical environment,ion exchange,and mineral saturation.Human activities in modern life can be further divided into industrial and agricultural sources primarily.(3)The health risks of fluoride contamination are very high in the Loess Plateau,especially for children compared to adults.Meanwhile,the risks of fluoride exposure through food intake are higher than those through drinking water intake.The authors suggest selecting target areas to improve water supply and ensure the safety of drinking water in the study area.Besides,it is necessary to plant crops with low fluoride content or cash crops and to conduct groundwater treatment to reduce the fluoride concentration in drinking water.These results will provide a theoretical basis for safe water supply in the faulted basin areas in the Loess Plateau.
文摘Samples of borehole water were randomly collected from twenty households in the Lagos-Ogun axis of southwestern Nigeria. The samples were analyzed for silver, iron, manganese, lead, nickel, magnesium, cadmium, zinc, sodium, potassium, pH, turbidity, dissolved oxygen, electrical conductivity, alkalinity, total hardness, chloride, nitrate and sulphate following standard methods of water analysis. Results obtained were compared with global background values and WHO guidelines for drinking water. The pH values ranged from 4.17 ± 0.26 to 6.07 ± 0.27 while the metal pollution indexes are between 0.01 and 0.11. Cadmium, manganese, iron and nitrate (mg/L) levels were found to be relatively high in most of the water samples. Results obtained were analyzed statistically. Health risk assessment for exposure to cancer and non-cancer indices was evaluated. Kempster and co-workers classification of drinking water quality was applied;nineteen of the twenty household water samples were found to fall short of the ideal water quality suitable for lifetime use.
文摘In the department of Zouan-Hounien, gold mining is booming. This activity, marked by the excavation of rocks and the use of chemicals such as mercury, is likely to contaminate the region’s groundwater resources and expose populations to serious diseases. This study aims to assess the health risks associated with the consumption of this water by the population. To this end, 72 groundwater samples were taken in eight (08) villages of the department at the rate of forty-six (46) well water samples and twenty-six (26) borehole water samples. A total of twenty-twenty-three wells and thirteen boreholes were sampled during two campaigns. An atomic absorption spectrometer (AAS) was used to determine the concentrations of metallic trace elements (MTEs), such as mercury (Hg), lead (Pb), cadmium (Cd), Arsenic (As), and iron (Fe) in the different samples. The daily exposure doses for oral ingestion (CDIing) and skin contact (Expderm) were calculated. The non-carcinogenic (HQ) and carcinogenic risks (CR) were estimated. The results show that the mean concentrations of Fe, Pb, Hg, As and Cd are respectively 2233.48 > 3.10 > 0.60 > 1.18 > 0.08 μg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>L<sup>-1</sup> in the wells and 2427.94 > 4.08 > 1.27 > 1.76 > 0.08 μg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span>L<sup>-1</sup> in boreholes. Evaluating the risks to human health reveals that the mean values of hazard quotient (HQ) and cancer risk (CR) for all the elements in the wells and boreholes are lower than 1 and 10<sup>-4</sup> respectively in children and adults for oral and dermal exposure. However, at the oral exposure level, 9 wells and 6 boreholes recorded HQ and CR above the define<span>d critical limits. These values indicate that the occurrence of non-cancero</span>us and cancerous diseases in populations consuming these waters by contamination with mercury and arsenic is not excluded. Dermal exposure to MTEs also poses no potential health risk to the population.
