Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces f...Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces for groundwater-surface water interaction,retaining potentially toxic elements(PTEs)and improving water quality in karst ecosystems.However,it remains uncertain whether the niche differentiation among moss species influences their capacity for the retention of PTEs.This study examines the petrifying spring-moss system in Tongren Grand Canyon,Guizhou Province,a typical karst region in southwestern China.Four dominant moss species with distinct ecological niches were selected for this study.Inductively coupled plasma mass spectrometry(ICPMS)was used to quantify PTEs in the petrifying springmoss systems and their associated water flows.Ecological niche analysis was integrated to evaluate the PTEs enrichment efficiencies of different petrifying spring-moss systems.The results identified Fissidens grandifrons Brid.,Hydrogonium majusculum(C.Muell.)Chen,Brachythecium curtum(Lindb.)Limpr.,and Cratoneuron filicinum(Hedw.)Spruc.var.filicinum as representative species of distinct ecological niches.After filtration through the petrifying spring-moss systems,the concentrations of PTEs in the water were significantly reduced(P<0.05).The retention capacities of moss species varied significantly across ecological niches and were ranked as follows:C.filicinum var.filicinum>B.curtum>F.grandifrons>H.majusculum.This study demonstrates that karst petrifying spring-moss systems efficiently intercept PTEs in groundwater and reveals,from a niche theory angle,the link between moss niche differentiation and their retention efficiency,which offers innovative strategies for ecological remediation of PTEs pollution in global karst groundwater systems.展开更多
The present study was conducted to examine the trophic transfer of potentially toxic elements(PTEs)in a closed arsenic mine.Eight PTEs in a soil-plant-leaf litter-earthworm-top predators(free-range local chicken and w...The present study was conducted to examine the trophic transfer of potentially toxic elements(PTEs)in a closed arsenic mine.Eight PTEs in a soil-plant-leaf litter-earthworm-top predators(free-range local chicken and wild passerine bird)system were analyzed for nitrogen and carbon stable isotopes,PTE concentrations,bioaccumulation factors(BAFs),and transfer factors(TFs).The PTE concentrations in soils from mining areas were generally higher than a adjacent controlled area,with As and Cd in soils showing the prominent compared to other six PTEs,as seen for the indices of geo-accumulation index(I_(geo)),pollution index(PI)and potential ecological risk index(RI).The relatively high BAF and TF values suggested a distinct biotransfer of PTEs along the soil-plant-leaf litter-earthworm system.BAFs were mostly<1 except in earthworms,indicating that earthworms had a strong capacity to take up these metals.The TFs varied both among PTEs and organism’s species,e.g.,the transfer capacities of As in Pteris vittata and Pteris cretica,Cd in Miscanthus sinensis,and Pb,Cr and Mn in moss were the highest.For local free-range chicken and wild passerine bird,the concentrations of PTEs were higher in gastric contents and feather than in internal tissue(stomach,liver and heart),with lower contents in muscle and egg.Bioaccumulation of PTEs generally decreased from decomposer earthworms,to primary producer plants,to top predator,indicating a potential bio-dilution tendency in higher trophic levels in the terrestrial food chain.展开更多
Under complicated field conditions,such as the coupled effects of freeze-thaw cycles(FTs)and acidification,the leaching behavior of potentially toxic element(PTEs)from indigenous Zn smelting slags(ZSS)was intricately ...Under complicated field conditions,such as the coupled effects of freeze-thaw cycles(FTs)and acidification,the leaching behavior of potentially toxic element(PTEs)from indigenous Zn smelting slags(ZSS)was intricately connected to the mineralogy(e.g.,the composition,assemblage,microstructure of mineral particles).In this study,FTs tests were carried out to explore the interactions between PTEs release and ZSSmineralogy.Subsequently,advanced characterization techniqueswere adopted to quantify the mineralogy andmicrostructure of ZSS.The results indicated that ZSS were mainly composed of silicate minerals(e.g.,quartz,biotite and chlorite)and secondary Fe(III)oxyhydroxides(e.g.,magnetite and limonite),accounting for 67.48% and 24.23%,respectively.The occurrence mode analysis revealed that 81.95%of As,21.31%of Pb and 7.77% of Zn were hosted in limonite.About 37.89%,59.34% and 34.50% of Cd,Pb and Zn were associated with carbonate bound fractions.Under FTs interacting with different pH conditions,the leaching concentrations of As,Cd,Cu,Pb and Zn did not significantly increase with the increase in FTs and pH.The microstructure damage of mineral particles in ZSS with the higher porosity was caused by both FTs and proton corrosion.More importantly,the geochemical modeling results suggested that the precipitation of hematite and magnetite,as well as the dissolution of arsenolite,might have little impacts on PTEs release under FTs and FTs with acidification.This work would provide a deeper understanding of PTEs release from smelting waste slags under complex physicochemical interactions.展开更多
The contamination of fish type products such as silver pomfret fish fillets by potentially toxic elements(PTEs)has raised global health concerns.Related studies regarding the concentration of PTEs in fillets of silver...The contamination of fish type products such as silver pomfret fish fillets by potentially toxic elements(PTEs)has raised global health concerns.Related studies regarding the concentration of PTEs in fillets of silver pomfret fish were retrieved among some international databases such as Scopus,Pub Med and Embase between 1 January 1983 and 10 March 2020.The pooled(mean)concentration of PTEs in fillets of silver pomfret fish was meta-analyzed with the aid of a random-effect model(REM).Also,the non-carcinogenic risk was estimated via calculating the 95 th percentile of the total target hazard quotient(TTHQ).The meta-analysis of 21 articles(containing 25 studies or data reports)indicated that the ranking of PTEs in fillets of silver pomfret fish was Fe(11,414.81μg/kg wet weight,ww)>Zn(6055.72μg/kg ww)>Cr(1825.79μg/kg ww)>Pb(1486.44μg/kg ww)>Se(1053.47μg/kg ww)>Cd(992.50μg/kg ww)>Ni(745.23μg/kg ww)>Cu(669.71μg/kg ww)>total As(408.24μg/kg ww)>Co(87.03μg/kg ww)>methyl Hg(46.58μg/kg ww).The rank order of health risk assessment by country based on the TTHQ for adult consumers was Malaysia(2.500)>Bangladesh(0.886)>Iran(0.144)>China(0.045)>Pakistan(0.020)>India(0.015),while the corresponding values for child consumers was Malaysia(11.790)>Bangladesh(4.146)>Iran(0.675)>China(0.206)>Pakistan(0.096)>India(0.077).The adult consumers in Malaysia and children in Malaysia and Bangladesh were at considerable non-carcinogenic risk.Therefore,following the recommended control plans in order to reduce the health risk associated with the ingestion of PTEs via consumption of silver pomfret fish fillets is crucial.展开更多
In this study,the sources of potentially toxic elements(PTEs)from atmospheric deposition in the waters of Guizhou’s Caohai Lake were investigated in addition to the potential risks to human health.Moss bags were used...In this study,the sources of potentially toxic elements(PTEs)from atmospheric deposition in the waters of Guizhou’s Caohai Lake were investigated in addition to the potential risks to human health.Moss bags were used to enrich PTEs from atmospheric deposition,and eight monitoring sites that best represented geographic variation were established around Caohai Lake.Moss bags were collected and examined at every 3 months to identify spatiotemporal patterns of dry and wet atmospheric deposition of PTEs.Zn was the most abundant metal identified from deposition in Caohai(72.07%–95.94%),followed by Pb and Cd,while Hg was the least abundant(0.008%–0.354%).The contributions of wet deposition of PTEs were greater than those of dry deposition,and deposition during the heating season from December to April was greater than that between April to July.Hg was mainly derived from atmospheric dry deposition(65.38%–84.44%).Spatial distribution analysis indicated that atmospheric deposition was associated with the intensity of human activities and heating emissions.Exposure via hand-to-mouth contact accounted for over 99%of the total exposure risk although overall exposure was lower than threshold acceptable levels for carcinogenic and non-carcinogenic metals,indicating an overall lack of risk towards human health.Nevertheless,the health risk from atmospheric deposition of PTEs in Caohai Lake may be reduced by focusing on Zn,Pb,and Cd deposition in rainfall and minimizing the hazards associated with hand-to-mouth exposure to PTEs.展开更多
A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flo...A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (ETAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD 5 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation.展开更多
This study investigated the feasibility of using some natural clay minerals available in Egypt like kaolinite, bentonite, also using of iron oxide, rock phosphate and mixture of these types to minimize the rate of Ni,...This study investigated the feasibility of using some natural clay minerals available in Egypt like kaolinite, bentonite, also using of iron oxide, rock phosphate and mixture of these types to minimize the rate of Ni, Cu, Zn and Mn desorption from sewage soils and to evaluate the effect of these mixtures on Zn equivalent constant values before and after remediation. The obtained results indicated that all mixtures used were minimizing the rate of potential toxic elements (PTE's) release from sewage soils compared to control treatment. According to the decreasing order of different treatments, data indicated that application of the mixture treatment of bentonite, kaolinite and rock phosphate (RP) in sewage soils becomes the best treatment compared to other treatments used. However, the lowest and save Zn equivalent constant value which represents the hazard indicator in the study was observed in sewage soil treated with the mixture of bentonite and RP. The kinetic constants of Elovich, modified Freundlich and Hoerl equations, the best fitted models, were significantly decreased compared to control treatments with different percent of minimization according to type of pollutants and remediation material used. To understand the mechanisms of PTE's retained in treated sewage soil, distribution study was applied which showed that different pollutants studied were removed to hardly available form different mechanisms of PTE's undergo in treated sewage soils were discussed in the study.展开更多
The Ker-Ya River flows through the high-tech industrial park and urban residential areas of Hsin-Chu in northern Taiwan. Major and trace element concentrations of waste effluents, river water, and sediment samples col...The Ker-Ya River flows through the high-tech industrial park and urban residential areas of Hsin-Chu in northern Taiwan. Major and trace element concentrations of waste effluents, river water, and sediment samples collected during 2017 along the Ker-Ya River were analyzed to elucidate the distribution pattern of potential pollutants. Principal component analyses were applied, and four major contaminant associations were recognized: 1) Ce, Co, Fe, La, V, and Cr;2) Cu and Ni associated with Hg, Ni, P, Ga, W, In, and Ti;3) B, Li, Ba, Ca, and Ag;and 4) Sn with Zn, In, and Cd. All associations are considered to be mainly anthropogenic. Although the element associations recognized from the water samples are not exactly the same as those from the sediment samples but nevertheless, they are similar, suggesting that the short-term and long-term distribution patterns are consistent. The A association accounts for the most variance in the data and exhibits the widest distribution, suggesting the existence of contaminant sources in the upper and lower reaches, respectively. The sediments near the outlet of the city sewage plant also contain association A elements, signaling incomplete processing of the diverged waters sent to the plant at the river mouth. The B association (mainly Cu and Ni) appeared mainly in the upper and middle reaches, indicative of sources from industries in the upper reaches and the tributary Nan-Men Creek. The C association (B, Ba, Ca, and Li) was limited to the center part of the river, probably attributable to a nearby paper mill. The D association (primarily Sn, In, and Zn) was present in the top point of the middle reaches, suggesting the presence of other contaminant sources in the upper reaches. Although a total of four concomitant associations were recognized, none of the elements exceeded the drinking water standard, suggesting that there was no severe pollution present.展开更多
The presence of toxic elements in paper and board food contact materials(FCMs)has been previously shown by various studies employing different sample preparation methods.This study elucidates the influence of migratio...The presence of toxic elements in paper and board food contact materials(FCMs)has been previously shown by various studies employing different sample preparation methods.This study elucidates the influence of migration methods on the migration of toxic elements from recycled paper FCMs to food simulants and compares these methods with exhaustive extraction approaches.Migration samples were prepared with four food simulants as specified in the Commission Regulation(EU)10/2011:3%(volume fraction)acetic acid,10%(volume fraction)and 50%(volume fraction)ethanol,and Tenax.The extraction process underestimated the number and quantity of elements.Migration methodologies revealed distinct element transfer patterns influenced by the physicochemical properties of the food simulants.Toxic elements,including aluminum,cobalt,nickel,arsenic,lead,cadmium,barium,and uranium,were detected in quantities exceeding safety reference values.These findings underscore the need for harmonized migration testing and regulatory-specific migration limits.展开更多
Toxic elements in the atmosphere can enter and accumulate in the human body, seriously impacting human health. In this study, we analyzed a 14-year (1995-2008) measurement of three toxic elements (As, Cd and Cr) i...Toxic elements in the atmosphere can enter and accumulate in the human body, seriously impacting human health. In this study, we analyzed a 14-year (1995-2008) measurement of three toxic elements (As, Cd and Cr) in PMlo in Hong Kong, China. The pollution of these toxic elements in Hong Kong was not serious. The trend analysis showed that As and Cr in PM10 increased at a statistically significant level (p〈0.05) during the 14-year period, while the Cd in PM10 did not change significantly. Typical seasonal variations were observed for all three toxic elements, largely in relation to the Asian monsoon. Hourly 10-day backward trajectories were computed and cate- gorised into four groups. The continental air masses showed much higher concentrations of the three toxic elements than the marine air masses. The abundances of As and Cd in the PM10 were much higher in the continental air masses than those in the marine air masses, while the abundances of Cr showed an opposite pattern. The trends of the three toxic elements in East China's air mass were consistent with those in the overall data set ofHong Kong. Examination of the toxic element data recorded at urban sites and a roadside site also indicated a large contribution of external air masses to particulate As and Cd in Hong Kong. These results suggest that the long-range transport from the mainland of China is the dominant contributor to particulate As and Cd, while both local and long-distance sources determine the particulate Cr in Hong Kong.展开更多
Objective This study was conducted to evaluate the concentration of potentially toxic elements(PTEs)such as arsenic(As),cadmium(Cd),mercury(Hg),and lead(Pb)in fruit samples collected from Markazi Province,Iran.A proba...Objective This study was conducted to evaluate the concentration of potentially toxic elements(PTEs)such as arsenic(As),cadmium(Cd),mercury(Hg),and lead(Pb)in fruit samples collected from Markazi Province,Iran.A probabilistic health risk assessment due to ingestion of PTEs through the consumption of these fruits was also conducted.Methods The concentration of PTEs in 90 samples of five types of fruits(n=3)collected from six geographic regions in Markazi Province was measured.The potential health risk was evaluated using a Monte Carlo simulation model.Results A significant difference was observed in the concentration of PTEs between fruits as well as soil and water samples collected from different regions in Markazi Province.The order of PTE concentration in the soil and water samples was as follows:Pb>As>Hg>Cd.Furthermore,the highest level of transfer factor for Cd and Hg correlated with the grape.The estimated daily intake for adults and children was lower than the recommended tolerable daily intake.Conclusion The population in Markazi Province,Iran,is not at considerable noncarcinogenic or carcinogenic risk due to the ingestion of PTEs through the consumption of the examined fruits.展开更多
The objective of the present study was to evaluate the relation between maternal blood levels of selected toxic and potentially toxic elements (manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium ...The objective of the present study was to evaluate the relation between maternal blood levels of selected toxic and potentially toxic elements (manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), lead (Pb) and mercury (Hg)) and birth weight of their new-borns in a Slovenian population, taking into account maternal socio-demographic characteristics and dietary habits. 535 women from 12 regions of Slovenia were recruited at delivery. Maternal blood was collected at 1.5 months after birth. Associations between birth weight and a) predictors obtained through the questionnaires and b) levels of selected elements were tested using bivariate tests and multiple linear regression. Multiple regression models revealed maternal age as an additional predictor for birth weight and confirmed pre-pregnancy body mass, estimated gestational age and gender of the baby as the main predictors for birth weight. Mn in maternal blood was significantly and positively associated with birth weight. The positive association observed between birth weight and Mn in maternal blood could be explained by the essentiality of Mn in foetal development as an important cofactor in enzymereactions in bone formation and in metabolic regulation for amino acid, lipid, protein and carbohydrate levels.展开更多
The essential and toxic element concentrations in buckwheat were analyzed by inductively coupled plasma optical emission spectrometer(ICP-OES).The concentration data were subjected to common chemometrics analyses,incl...The essential and toxic element concentrations in buckwheat were analyzed by inductively coupled plasma optical emission spectrometer(ICP-OES).The concentration data were subjected to common chemometrics analyses,including correlation analysis(CA),principal component analysis(PCA)and hierarchical cluster analysis(HCA),to gain better understanding of the differences among the tested samples.Our results indicated that the essential and toxic element concentrations were not different between Fagopyrum tataricum(L.)Gaertn and F.esculentum Moench.The element concentrations varied among buckwheat samples from different sources.Commercial tartary buckwheat tea contained several essential elements,thus,could be used as the source of essential elements.The detection of toxic heavy metals in commercial tartary buckwheat tea suggested that safety issue of such buckwheat products should be seriously concerned.Our results also revealed that the place of origin and the processing protocol of tartary buckwheat affected the element concentrations of the commercial form.The implications to the quality control and safety evaluation of buckwheat were extensively discussed.展开更多
Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants ...Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.展开更多
Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals (e.g., Cd and Pb in Pb/Zn mines). However, previous studies on rice cultivars screened for effective metal exclusion...Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals (e.g., Cd and Pb in Pb/Zn mines). However, previous studies on rice cultivars screened for effective metal exclusion have mostly focused on individual metals, and have been conducted under pot-trial or hydroponic solution conditions. This study identified rice cultlvars with both low Cd and Pb accumulation under Cd- and Pb-contaminated field conditions, and the interactions of the toxic elements Cd and Pb with the micronutrient elements Fe, Zn, Mn and Ni were also studied. Among 32 rice cultivars tested, there were significant differences in Cd (0.06-0.59 mg/kg) and Pb (0.25-3.15 mg/kg) levels in their brown rice, and similar results were also found for the micronutrient elements. Significant decreases in concentrations of Fe and Mn were detected with increasing Cd concentrations and a significant elevation in Fe, Mn and Ni with increasing Pb concentrations. A similar result was also shown by Cd and Ni. Three cultivars were identified with a combination of low brown rice Cd and Pb, high micronutrient and grain yield (Wufengyou 2168, Tianyou 196 and Guinongzhan). Present results suggest that it is possible to breed rice eultivars with low mixed toxic element (Cd, Pb) and high micronutrient contents along with high grain yields, thus ensuring food safety and quality.展开更多
The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results...The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results show that As, Cd, Pb and Zn are major contaminants in sediments, and average concentrations of these elements significantly exceed both the Control Standards for Pollutants in Sludge of China (GB4284-84) for agricultural use in acidic soils and the effect range median (ERM) values. The average concentrations of As, Cd and Pb in the river water slightly exceed the limit of Surface Water Environment Quality Standard (GB3838-2002). The concentrations of As and Cr in depth profiles extensively change, but slight changes are observed in Pb and Zn. Cd and Zn in most sediment samples can easily enter the food-chain and bring possible ecotoxicological risk to organisms living in sediments according to the risk assessment code.展开更多
Phosphogypsum(PG),a hard-to-dissipate by-product of the phosphorus fertilizer production industry,places strain on the biogeochemical cycles and ecosystem functions of storage sites.This pervasive problem is already w...Phosphogypsum(PG),a hard-to-dissipate by-product of the phosphorus fertilizer production industry,places strain on the biogeochemical cycles and ecosystem functions of storage sites.This pervasive problem is already widespread worldwide and requires careful stewardship.In this study,we review the presence of potentially toxic elements(PTEs)in PG and describe their associations with soil properties,anthropogenic activities,and surrounding organisms.Then,we review different ex-/in-situ solutions for promoting the sustainable management of PG,with an emphasis on in-situ cemented paste backfill,which offers a cost-effective and highly scalable opportunity to advance the value-added recovery of PG.However,concerns related to the PTEs'retention capacity and long-term effectiveness limit the implementation of this strategy.Furthermore,given that the large-scale demand for ordinary Portland cement from this conventional option has resulted in significant CO_(2) emissions,the technology has recently undergone additional scrutiny to meet the climate mitigation ambition of the Paris Agreement and China's Carbon Neutrality Economy.Therefore,we discuss the ways by which we can integrate innovative strategies,including supplementary cementitious materials,alternative binder solutions,CO_(2) mineralization,CO_(2) curing,and optimization of the supply chain for the profitability and sustainability of PG remediation.However,to maximize the co-benefits in environmental,social,and economic,future research must bridge the gap between the feasibility of expanding these advanced pathways and the multidisciplinary needs.展开更多
B and N mixed anions co-doped titania with various crystal phases such as anatase,brookite,and rutile were successfully synthesized by a hydrothermal synthesis followed by heat treatment in an ammonia gas atmosphere a...B and N mixed anions co-doped titania with various crystal phases such as anatase,brookite,and rutile were successfully synthesized by a hydrothermal synthesis followed by heat treatment in an ammonia gas atmosphere at 550-650℃(denoted as BN-Ana_x,BN-Bro_x,and BN-Rut_x,x is the treatment temperature).The colors of as-prepared BN-Ana,BN-Bro,and BN-Rut are red,yellow-green,and cyangreen,respectively.The color changing mechanism of titania was related to their various band gap structure and the existence of B-N bonding.The nitridation temperature exhibits effective color changing compared to that of nitridation time.The different phases of the mixed anion codoped titania possess different photocatalytic deNO_(x) activity.The BN-Ana and BN-Rut show poor photocatalytic deNO_(x) activity,while the BN-Bro shows excellent photocatalytic deNO_(x) activity,better than that of standard titania photocatalyst Degussa P25.The colorful titania with low-photocatalytic activity is heavy metal elements free,indicating their possible applications as nontoxic color pigments or novel cosmetic raw materials.展开更多
A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model cor...A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts.展开更多
Background: Groundwater is an important source of water. Since the control and removal of pollution are expensive, it is essential to identify the possible sources of contamination and to correctly classify groundwate...Background: Groundwater is an important source of water. Since the control and removal of pollution are expensive, it is essential to identify the possible sources of contamination and to correctly classify groundwater on the basis of its intrinsic and integrated vulnerability. Objectives: To group ground water chemical ions and heavy metals parameters into similar groups. Method: The investigation made use of standard analytical procedures. All sampling, conservation, transportation and analysis followed standard procedures described in APHA (2012). To prevent degradation of the organic substances, all obtained samples were transferred to the laboratory, while kept in an icebox. Results: Sampling records from the same area are generally assigned to the same cluster during hierarchical cluster analysis (HCA). The cluster diagram shows the grouping of the heavy metal in the study area during wet and dry seasons. It reveals that 5 distinct clusters were identified for wet season and 4 clusters were identified during dry season. Also, it reveals that 5 distinct clusters were identified for wet season and for dry season, 4 distinct clusters were identified. Conclusion: The findings of this study are significant for policymakers and agencies in terms of dealing with the issues identified to enhance sustainable livelihood practices in the oil rich Niger Delta region of Nigeria. Therefore, decision-makers should take proper initiatives to get local people aware of the endangered zones before use, as drinking water is key to good health. Similarly, multinational oil companies will find it useful in their quest for viable social corporate responsibility and remediation plans in their respective host communities. The method proved to be a useful and objective tool for environmental planning.展开更多
基金the National Nature Science Foundation of China(No.32360052)the Department of Science and Technology Foundation of Guizhou Province,China[No.2017(5742)]。
文摘Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces for groundwater-surface water interaction,retaining potentially toxic elements(PTEs)and improving water quality in karst ecosystems.However,it remains uncertain whether the niche differentiation among moss species influences their capacity for the retention of PTEs.This study examines the petrifying spring-moss system in Tongren Grand Canyon,Guizhou Province,a typical karst region in southwestern China.Four dominant moss species with distinct ecological niches were selected for this study.Inductively coupled plasma mass spectrometry(ICPMS)was used to quantify PTEs in the petrifying springmoss systems and their associated water flows.Ecological niche analysis was integrated to evaluate the PTEs enrichment efficiencies of different petrifying spring-moss systems.The results identified Fissidens grandifrons Brid.,Hydrogonium majusculum(C.Muell.)Chen,Brachythecium curtum(Lindb.)Limpr.,and Cratoneuron filicinum(Hedw.)Spruc.var.filicinum as representative species of distinct ecological niches.After filtration through the petrifying spring-moss systems,the concentrations of PTEs in the water were significantly reduced(P<0.05).The retention capacities of moss species varied significantly across ecological niches and were ranked as follows:C.filicinum var.filicinum>B.curtum>F.grandifrons>H.majusculum.This study demonstrates that karst petrifying spring-moss systems efficiently intercept PTEs in groundwater and reveals,from a niche theory angle,the link between moss niche differentiation and their retention efficiency,which offers innovative strategies for ecological remediation of PTEs pollution in global karst groundwater systems.
基金supported by the National Natural Science Foundation of China(Nos.41907325 and 41571470).
文摘The present study was conducted to examine the trophic transfer of potentially toxic elements(PTEs)in a closed arsenic mine.Eight PTEs in a soil-plant-leaf litter-earthworm-top predators(free-range local chicken and wild passerine bird)system were analyzed for nitrogen and carbon stable isotopes,PTE concentrations,bioaccumulation factors(BAFs),and transfer factors(TFs).The PTE concentrations in soils from mining areas were generally higher than a adjacent controlled area,with As and Cd in soils showing the prominent compared to other six PTEs,as seen for the indices of geo-accumulation index(I_(geo)),pollution index(PI)and potential ecological risk index(RI).The relatively high BAF and TF values suggested a distinct biotransfer of PTEs along the soil-plant-leaf litter-earthworm system.BAFs were mostly<1 except in earthworms,indicating that earthworms had a strong capacity to take up these metals.The TFs varied both among PTEs and organism’s species,e.g.,the transfer capacities of As in Pteris vittata and Pteris cretica,Cd in Miscanthus sinensis,and Pb,Cr and Mn in moss were the highest.For local free-range chicken and wild passerine bird,the concentrations of PTEs were higher in gastric contents and feather than in internal tissue(stomach,liver and heart),with lower contents in muscle and egg.Bioaccumulation of PTEs generally decreased from decomposer earthworms,to primary producer plants,to top predator,indicating a potential bio-dilution tendency in higher trophic levels in the terrestrial food chain.
基金supported by the National Key Research and Development Program of China(Nos.2023YFC3707704 and 2019YFC1805205)the Research Initiation Fund and the 16th Batch of Sailing Plan Project of China University of Mining and Technology(Nos.102524004 and 102524096)the key scientific research projects(No.ZMYJJB-2024-01)of First Exploration Burea,China National Administration of coal Geology.
文摘Under complicated field conditions,such as the coupled effects of freeze-thaw cycles(FTs)and acidification,the leaching behavior of potentially toxic element(PTEs)from indigenous Zn smelting slags(ZSS)was intricately connected to the mineralogy(e.g.,the composition,assemblage,microstructure of mineral particles).In this study,FTs tests were carried out to explore the interactions between PTEs release and ZSSmineralogy.Subsequently,advanced characterization techniqueswere adopted to quantify the mineralogy andmicrostructure of ZSS.The results indicated that ZSS were mainly composed of silicate minerals(e.g.,quartz,biotite and chlorite)and secondary Fe(III)oxyhydroxides(e.g.,magnetite and limonite),accounting for 67.48% and 24.23%,respectively.The occurrence mode analysis revealed that 81.95%of As,21.31%of Pb and 7.77% of Zn were hosted in limonite.About 37.89%,59.34% and 34.50% of Cd,Pb and Zn were associated with carbonate bound fractions.Under FTs interacting with different pH conditions,the leaching concentrations of As,Cd,Cu,Pb and Zn did not significantly increase with the increase in FTs and pH.The microstructure damage of mineral particles in ZSS with the higher porosity was caused by both FTs and proton corrosion.More importantly,the geochemical modeling results suggested that the precipitation of hematite and magnetite,as well as the dissolution of arsenolite,might have little impacts on PTEs release under FTs and FTs with acidification.This work would provide a deeper understanding of PTEs release from smelting waste slags under complex physicochemical interactions.
基金the student research committee at Shahid Beheshti University of Medical Sciences for the financial grants supporting this study(1398/9920)。
文摘The contamination of fish type products such as silver pomfret fish fillets by potentially toxic elements(PTEs)has raised global health concerns.Related studies regarding the concentration of PTEs in fillets of silver pomfret fish were retrieved among some international databases such as Scopus,Pub Med and Embase between 1 January 1983 and 10 March 2020.The pooled(mean)concentration of PTEs in fillets of silver pomfret fish was meta-analyzed with the aid of a random-effect model(REM).Also,the non-carcinogenic risk was estimated via calculating the 95 th percentile of the total target hazard quotient(TTHQ).The meta-analysis of 21 articles(containing 25 studies or data reports)indicated that the ranking of PTEs in fillets of silver pomfret fish was Fe(11,414.81μg/kg wet weight,ww)>Zn(6055.72μg/kg ww)>Cr(1825.79μg/kg ww)>Pb(1486.44μg/kg ww)>Se(1053.47μg/kg ww)>Cd(992.50μg/kg ww)>Ni(745.23μg/kg ww)>Cu(669.71μg/kg ww)>total As(408.24μg/kg ww)>Co(87.03μg/kg ww)>methyl Hg(46.58μg/kg ww).The rank order of health risk assessment by country based on the TTHQ for adult consumers was Malaysia(2.500)>Bangladesh(0.886)>Iran(0.144)>China(0.045)>Pakistan(0.020)>India(0.015),while the corresponding values for child consumers was Malaysia(11.790)>Bangladesh(4.146)>Iran(0.675)>China(0.206)>Pakistan(0.096)>India(0.077).The adult consumers in Malaysia and children in Malaysia and Bangladesh were at considerable non-carcinogenic risk.Therefore,following the recommended control plans in order to reduce the health risk associated with the ingestion of PTEs via consumption of silver pomfret fish fillets is crucial.
基金supported by the National Natural Science Foundation of China(21767006)The Science and Technology of Guizhou Province,China([2018]2349)。
文摘In this study,the sources of potentially toxic elements(PTEs)from atmospheric deposition in the waters of Guizhou’s Caohai Lake were investigated in addition to the potential risks to human health.Moss bags were used to enrich PTEs from atmospheric deposition,and eight monitoring sites that best represented geographic variation were established around Caohai Lake.Moss bags were collected and examined at every 3 months to identify spatiotemporal patterns of dry and wet atmospheric deposition of PTEs.Zn was the most abundant metal identified from deposition in Caohai(72.07%–95.94%),followed by Pb and Cd,while Hg was the least abundant(0.008%–0.354%).The contributions of wet deposition of PTEs were greater than those of dry deposition,and deposition during the heating season from December to April was greater than that between April to July.Hg was mainly derived from atmospheric dry deposition(65.38%–84.44%).Spatial distribution analysis indicated that atmospheric deposition was associated with the intensity of human activities and heating emissions.Exposure via hand-to-mouth contact accounted for over 99%of the total exposure risk although overall exposure was lower than threshold acceptable levels for carcinogenic and non-carcinogenic metals,indicating an overall lack of risk towards human health.Nevertheless,the health risk from atmospheric deposition of PTEs in Caohai Lake may be reduced by focusing on Zn,Pb,and Cd deposition in rainfall and minimizing the hazards associated with hand-to-mouth exposure to PTEs.
文摘A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (ETAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD 5 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation.
文摘This study investigated the feasibility of using some natural clay minerals available in Egypt like kaolinite, bentonite, also using of iron oxide, rock phosphate and mixture of these types to minimize the rate of Ni, Cu, Zn and Mn desorption from sewage soils and to evaluate the effect of these mixtures on Zn equivalent constant values before and after remediation. The obtained results indicated that all mixtures used were minimizing the rate of potential toxic elements (PTE's) release from sewage soils compared to control treatment. According to the decreasing order of different treatments, data indicated that application of the mixture treatment of bentonite, kaolinite and rock phosphate (RP) in sewage soils becomes the best treatment compared to other treatments used. However, the lowest and save Zn equivalent constant value which represents the hazard indicator in the study was observed in sewage soil treated with the mixture of bentonite and RP. The kinetic constants of Elovich, modified Freundlich and Hoerl equations, the best fitted models, were significantly decreased compared to control treatments with different percent of minimization according to type of pollutants and remediation material used. To understand the mechanisms of PTE's retained in treated sewage soil, distribution study was applied which showed that different pollutants studied were removed to hardly available form different mechanisms of PTE's undergo in treated sewage soils were discussed in the study.
文摘The Ker-Ya River flows through the high-tech industrial park and urban residential areas of Hsin-Chu in northern Taiwan. Major and trace element concentrations of waste effluents, river water, and sediment samples collected during 2017 along the Ker-Ya River were analyzed to elucidate the distribution pattern of potential pollutants. Principal component analyses were applied, and four major contaminant associations were recognized: 1) Ce, Co, Fe, La, V, and Cr;2) Cu and Ni associated with Hg, Ni, P, Ga, W, In, and Ti;3) B, Li, Ba, Ca, and Ag;and 4) Sn with Zn, In, and Cd. All associations are considered to be mainly anthropogenic. Although the element associations recognized from the water samples are not exactly the same as those from the sediment samples but nevertheless, they are similar, suggesting that the short-term and long-term distribution patterns are consistent. The A association accounts for the most variance in the data and exhibits the widest distribution, suggesting the existence of contaminant sources in the upper and lower reaches, respectively. The sediments near the outlet of the city sewage plant also contain association A elements, signaling incomplete processing of the diverged waters sent to the plant at the river mouth. The B association (mainly Cu and Ni) appeared mainly in the upper and middle reaches, indicative of sources from industries in the upper reaches and the tributary Nan-Men Creek. The C association (B, Ba, Ca, and Li) was limited to the center part of the river, probably attributable to a nearby paper mill. The D association (primarily Sn, In, and Zn) was present in the top point of the middle reaches, suggesting the presence of other contaminant sources in the upper reaches. Although a total of four concomitant associations were recognized, none of the elements exceeded the drinking water standard, suggesting that there was no severe pollution present.
基金funded by the Netherlands Food and Consumer Product Safety Authority(NVWA)under the Ministry of Agriculture,Nature and Food Quality of the Netherlands with funding number 1400011703.
文摘The presence of toxic elements in paper and board food contact materials(FCMs)has been previously shown by various studies employing different sample preparation methods.This study elucidates the influence of migration methods on the migration of toxic elements from recycled paper FCMs to food simulants and compares these methods with exhaustive extraction approaches.Migration samples were prepared with four food simulants as specified in the Commission Regulation(EU)10/2011:3%(volume fraction)acetic acid,10%(volume fraction)and 50%(volume fraction)ethanol,and Tenax.The extraction process underestimated the number and quantity of elements.Migration methodologies revealed distinct element transfer patterns influenced by the physicochemical properties of the food simulants.Toxic elements,including aluminum,cobalt,nickel,arsenic,lead,cadmium,barium,and uranium,were detected in quantities exceeding safety reference values.These findings underscore the need for harmonized migration testing and regulatory-specific migration limits.
文摘Toxic elements in the atmosphere can enter and accumulate in the human body, seriously impacting human health. In this study, we analyzed a 14-year (1995-2008) measurement of three toxic elements (As, Cd and Cr) in PMlo in Hong Kong, China. The pollution of these toxic elements in Hong Kong was not serious. The trend analysis showed that As and Cr in PM10 increased at a statistically significant level (p〈0.05) during the 14-year period, while the Cd in PM10 did not change significantly. Typical seasonal variations were observed for all three toxic elements, largely in relation to the Asian monsoon. Hourly 10-day backward trajectories were computed and cate- gorised into four groups. The continental air masses showed much higher concentrations of the three toxic elements than the marine air masses. The abundances of As and Cd in the PM10 were much higher in the continental air masses than those in the marine air masses, while the abundances of Cr showed an opposite pattern. The trends of the three toxic elements in East China's air mass were consistent with those in the overall data set ofHong Kong. Examination of the toxic element data recorded at urban sites and a roadside site also indicated a large contribution of external air masses to particulate As and Cd in Hong Kong. These results suggest that the long-range transport from the mainland of China is the dominant contributor to particulate As and Cd, while both local and long-distance sources determine the particulate Cr in Hong Kong.
基金supported by the Payame Noor University (PNU), Tehran, Iran
文摘Objective This study was conducted to evaluate the concentration of potentially toxic elements(PTEs)such as arsenic(As),cadmium(Cd),mercury(Hg),and lead(Pb)in fruit samples collected from Markazi Province,Iran.A probabilistic health risk assessment due to ingestion of PTEs through the consumption of these fruits was also conducted.Methods The concentration of PTEs in 90 samples of five types of fruits(n=3)collected from six geographic regions in Markazi Province was measured.The potential health risk was evaluated using a Monte Carlo simulation model.Results A significant difference was observed in the concentration of PTEs between fruits as well as soil and water samples collected from different regions in Markazi Province.The order of PTE concentration in the soil and water samples was as follows:Pb>As>Hg>Cd.Furthermore,the highest level of transfer factor for Cd and Hg correlated with the grape.The estimated daily intake for adults and children was lower than the recommended tolerable daily intake.Conclusion The population in Markazi Province,Iran,is not at considerable noncarcinogenic or carcinogenic risk due to the ingestion of PTEs through the consumption of the examined fruits.
文摘The objective of the present study was to evaluate the relation between maternal blood levels of selected toxic and potentially toxic elements (manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), lead (Pb) and mercury (Hg)) and birth weight of their new-borns in a Slovenian population, taking into account maternal socio-demographic characteristics and dietary habits. 535 women from 12 regions of Slovenia were recruited at delivery. Maternal blood was collected at 1.5 months after birth. Associations between birth weight and a) predictors obtained through the questionnaires and b) levels of selected elements were tested using bivariate tests and multiple linear regression. Multiple regression models revealed maternal age as an additional predictor for birth weight and confirmed pre-pregnancy body mass, estimated gestational age and gender of the baby as the main predictors for birth weight. Mn in maternal blood was significantly and positively associated with birth weight. The positive association observed between birth weight and Mn in maternal blood could be explained by the essentiality of Mn in foetal development as an important cofactor in enzymereactions in bone formation and in metabolic regulation for amino acid, lipid, protein and carbohydrate levels.
基金the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAI27B07)the National Natural Science Foundation of China(81173653)+2 种基金the Administration of Traditional Chinese Medicine Department of Sichuan Province,China(2010-78)the Research Funds of Southwest University for Nationalities,China(13NLY01)the Earmarked Fund for China Agriculture Research System(CARS-08-D-3)
文摘The essential and toxic element concentrations in buckwheat were analyzed by inductively coupled plasma optical emission spectrometer(ICP-OES).The concentration data were subjected to common chemometrics analyses,including correlation analysis(CA),principal component analysis(PCA)and hierarchical cluster analysis(HCA),to gain better understanding of the differences among the tested samples.Our results indicated that the essential and toxic element concentrations were not different between Fagopyrum tataricum(L.)Gaertn and F.esculentum Moench.The element concentrations varied among buckwheat samples from different sources.Commercial tartary buckwheat tea contained several essential elements,thus,could be used as the source of essential elements.The detection of toxic heavy metals in commercial tartary buckwheat tea suggested that safety issue of such buckwheat products should be seriously concerned.Our results also revealed that the place of origin and the processing protocol of tartary buckwheat affected the element concentrations of the commercial form.The implications to the quality control and safety evaluation of buckwheat were extensively discussed.
基金financially supported by the Polish Ministry of Science and Higher Education(No.DS 3500)
文摘Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.
基金supported by the National Natural Science Foundation of China (No. 30770417,31070450)the NSFC-Guangdong United Foundation (No. U0833004)the Natural Science Foundation of Guangdong,China(No. 07003650,10151027501000008)
文摘Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals (e.g., Cd and Pb in Pb/Zn mines). However, previous studies on rice cultivars screened for effective metal exclusion have mostly focused on individual metals, and have been conducted under pot-trial or hydroponic solution conditions. This study identified rice cultlvars with both low Cd and Pb accumulation under Cd- and Pb-contaminated field conditions, and the interactions of the toxic elements Cd and Pb with the micronutrient elements Fe, Zn, Mn and Ni were also studied. Among 32 rice cultivars tested, there were significant differences in Cd (0.06-0.59 mg/kg) and Pb (0.25-3.15 mg/kg) levels in their brown rice, and similar results were also found for the micronutrient elements. Significant decreases in concentrations of Fe and Mn were detected with increasing Cd concentrations and a significant elevation in Fe, Mn and Ni with increasing Pb concentrations. A similar result was also shown by Cd and Ni. Three cultivars were identified with a combination of low brown rice Cd and Pb, high micronutrient and grain yield (Wufengyou 2168, Tianyou 196 and Guinongzhan). Present results suggest that it is possible to breed rice eultivars with low mixed toxic element (Cd, Pb) and high micronutrient contents along with high grain yields, thus ensuring food safety and quality.
基金Project (20507022) supported by the National Natural Science Foundation of ChinaProject (EREH050303) supported by the Foundation of Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health
文摘The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results show that As, Cd, Pb and Zn are major contaminants in sediments, and average concentrations of these elements significantly exceed both the Control Standards for Pollutants in Sludge of China (GB4284-84) for agricultural use in acidic soils and the effect range median (ERM) values. The average concentrations of As, Cd and Pb in the river water slightly exceed the limit of Surface Water Environment Quality Standard (GB3838-2002). The concentrations of As and Cr in depth profiles extensively change, but slight changes are observed in Pb and Zn. Cd and Zn in most sediment samples can easily enter the food-chain and bring possible ecotoxicological risk to organisms living in sediments according to the risk assessment code.
基金the National Natural Science Foundation of China(Nos.552104156,52074351,and 52004330)the National Natural Science Foundation of Hunan Province,China(No.2022JJ30714)the Science and Technology Innovation Program of Hunan Province,China(No.2021RC3125)。
文摘Phosphogypsum(PG),a hard-to-dissipate by-product of the phosphorus fertilizer production industry,places strain on the biogeochemical cycles and ecosystem functions of storage sites.This pervasive problem is already widespread worldwide and requires careful stewardship.In this study,we review the presence of potentially toxic elements(PTEs)in PG and describe their associations with soil properties,anthropogenic activities,and surrounding organisms.Then,we review different ex-/in-situ solutions for promoting the sustainable management of PG,with an emphasis on in-situ cemented paste backfill,which offers a cost-effective and highly scalable opportunity to advance the value-added recovery of PG.However,concerns related to the PTEs'retention capacity and long-term effectiveness limit the implementation of this strategy.Furthermore,given that the large-scale demand for ordinary Portland cement from this conventional option has resulted in significant CO_(2) emissions,the technology has recently undergone additional scrutiny to meet the climate mitigation ambition of the Paris Agreement and China's Carbon Neutrality Economy.Therefore,we discuss the ways by which we can integrate innovative strategies,including supplementary cementitious materials,alternative binder solutions,CO_(2) mineralization,CO_(2) curing,and optimization of the supply chain for the profitability and sustainability of PG remediation.However,to maximize the co-benefits in environmental,social,and economic,future research must bridge the gap between the feasibility of expanding these advanced pathways and the multidisciplinary needs.
基金supported by the KOSéCosmetology Research Foundationthe Japan Society funded the present work for the Promotion of Science (JSPS)Grant-in-Aid for Scientific Research (Nos.16H06439 and 20H00297)。
文摘B and N mixed anions co-doped titania with various crystal phases such as anatase,brookite,and rutile were successfully synthesized by a hydrothermal synthesis followed by heat treatment in an ammonia gas atmosphere at 550-650℃(denoted as BN-Ana_x,BN-Bro_x,and BN-Rut_x,x is the treatment temperature).The colors of as-prepared BN-Ana,BN-Bro,and BN-Rut are red,yellow-green,and cyangreen,respectively.The color changing mechanism of titania was related to their various band gap structure and the existence of B-N bonding.The nitridation temperature exhibits effective color changing compared to that of nitridation time.The different phases of the mixed anion codoped titania possess different photocatalytic deNO_(x) activity.The BN-Ana and BN-Rut show poor photocatalytic deNO_(x) activity,while the BN-Bro shows excellent photocatalytic deNO_(x) activity,better than that of standard titania photocatalyst Degussa P25.The colorful titania with low-photocatalytic activity is heavy metal elements free,indicating their possible applications as nontoxic color pigments or novel cosmetic raw materials.
基金financially supported from the National Key Research and Development Program of China(No.2019YFC1803601)the Fundamental Research Funds for the Central Universities of Central South University,China(No.2023ZZTS0801)+1 种基金the Postgraduate Innovative Project of Central South University,China(No.2023XQLH068)the Postgraduate Scientific Research Innovation Project of Hunan Province,China(No.QL20230054)。
文摘A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts.
文摘Background: Groundwater is an important source of water. Since the control and removal of pollution are expensive, it is essential to identify the possible sources of contamination and to correctly classify groundwater on the basis of its intrinsic and integrated vulnerability. Objectives: To group ground water chemical ions and heavy metals parameters into similar groups. Method: The investigation made use of standard analytical procedures. All sampling, conservation, transportation and analysis followed standard procedures described in APHA (2012). To prevent degradation of the organic substances, all obtained samples were transferred to the laboratory, while kept in an icebox. Results: Sampling records from the same area are generally assigned to the same cluster during hierarchical cluster analysis (HCA). The cluster diagram shows the grouping of the heavy metal in the study area during wet and dry seasons. It reveals that 5 distinct clusters were identified for wet season and 4 clusters were identified during dry season. Also, it reveals that 5 distinct clusters were identified for wet season and for dry season, 4 distinct clusters were identified. Conclusion: The findings of this study are significant for policymakers and agencies in terms of dealing with the issues identified to enhance sustainable livelihood practices in the oil rich Niger Delta region of Nigeria. Therefore, decision-makers should take proper initiatives to get local people aware of the endangered zones before use, as drinking water is key to good health. Similarly, multinational oil companies will find it useful in their quest for viable social corporate responsibility and remediation plans in their respective host communities. The method proved to be a useful and objective tool for environmental planning.