Silica(SiO_(2))nanoparticles(nSiO_(2))have attracted considerable attention in agricultural practices.However,their effects on polycyclic aromatic hydrocarbon(PAH)accumulation in plants remain largely unknown.Thus,thi...Silica(SiO_(2))nanoparticles(nSiO_(2))have attracted considerable attention in agricultural practices.However,their effects on polycyclic aromatic hydrocarbon(PAH)accumulation in plants remain largely unknown.Thus,this issue was tracked here with a 30-d pot experiment with foliar spraying of 30 and 100 nm SiO_(2) particles(100 mg L-1,10 mL)on Amaranthus tricolor L.(amaranth).Compared with foliar spraying of ultrapure water(i.e.,the control),foliar spraying of nSiO_(2) increased phenanthrene(PHE)contents in amaranth leaves by 242%±88.4%and 158%±29.6%,respectively,and the increases were significantly higher than that by foliar spraying of 2μm particles(96.0%±29.2%).Metabolomics analysis indicated that compared to nSiO_(2),2μm SiO_(2) significantly boosted oxidative defense in amaranth leaves,enhanced cell membrane fluidity,and upregulated amino acid metabolism,glycolysis,and gluconeogenesis.In addition,the upregulation of discriminating metabolites was the most significant in the 2μm SiO_(2) treatment,followed by the 100 and 30 nm nSiO_(2) treatments.This is mainly because nSiO_(2) promoted amaranth growth and decreased average PHE content per unit biomass,namely dilute effect.Thus,slighter metabolic disturbances were observed in the 30 and 100 nm SiO_(2) treatments compared with the control and 2μm SiO_(2) treatment.This study revealed the possibility of PAH accumulation enhancement in vegetables with foliar spraying of nSiO_(2).The results of this study provide theoretical guidance regarding particle size selection for the safe agricultural application of SiO_(2) in PAH-contaminated areas.展开更多
Diabetes and impaired fasting glucose(IFG)are significant global health concerns.However,the potential effects of mixed heavy metal exposure on these conditions remain underexplored.This study aims to investigate the ...Diabetes and impaired fasting glucose(IFG)are significant global health concerns.However,the potential effects of mixed heavy metal exposure on these conditions remain underexplored.This study aims to investigate the combined effects of multiple metals on diabetes risk and explore the mediating role of BodyMass Index(BMI)in rural China.Across-sectional analysis involved 2313 adults from 12 provinces in rural China.Urinary levels of zinc(Zn),chromium(Cr),nickel(Ni),cadmium(Cd),and lead(Pb)were quantified using inductively coupled plasma mass spectrometry.Fasting blood glucose(FBG)levels were measured with an automatic biochemical analyzer.Logistic regression models and the Bayesian Kernel Machine Regression(BKMR)model were used to examine associations and interactions.Mediation analysis was performed to assess the role of BMI.The results of our study indicate that there is a significant association between urinary Zn(OR=2.38,95%CI:1.57,3.60),Cr(OR=1.24,95%CI:1.31,1.61),and Ni(OR=1.51,95%CI:1.05,2.18)and the diabetes risk.The study revealed that exposure to Ni amplified the associations between Zn,Cr and diabetes/IFG risk.Additionally,BMI was identified as a significant mediator in the relationship between metal exposure,particularly Cr/Cd,and diabetes risk.These findings reveal a complex link between multiple metals,such as Zn,Cr,and Ni,and diabetes risk,and emphasize the potential opposite mediating effects of BMI in different metal-induced diabetes mechanisms.Further investigation of these mechanisms is warranted.展开更多
Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formatio...Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.展开更多
Sediment is the ultimate sink of environmental pollutants.A total of 128 surface sediment sampleswere collected from8 rivers and 3 reservoirs in Maoming City,Guangdong Province.This study assessed the content and dist...Sediment is the ultimate sink of environmental pollutants.A total of 128 surface sediment sampleswere collected from8 rivers and 3 reservoirs in Maoming City,Guangdong Province.This study assessed the content and distribution of brominated flame retardants in sediments.The acute toxicity effects of tetrabromobisphenol A(TBBPA)and hexabromocyclododecane(HBCDs)in sediments were evaluated using Caenorhabditis elegans as model organisms.The concentration of TBBPA in sediments ranged from not detected(ND)to 12.59μg/kg andwas mainly distributed in the central area,whichwas affected by the emission of TBBPA from residential and factory.The concentration of HBCDs ranged from ND to 6.31μg/kg,and the diastereoisomer distribution was consistent,showing a trend close to the South China Sea.The composition pattern of HBCDs in the surface sediments from rivers were 41.73%-62.33%,7.89%-25.54%,and 18.76%-40.65%forα-,β-,andγ-HBCD,respectively,and in the sediments from reservoirs were 26.15%-45.52%,7.44%-19.23%,and 47.04%-61.89%forα-,β-,andγ-HBCD,respectively.When the sum of concentrations of TBBPA and HBCD in sediments were above high levels,reactive oxygen species in nematodes significantly increased,resulting in an oxidative stress response.Intestinal permeabilitywas also enhanced,causing intestinal damage.In addition,in terms of this study,TBBPA had a greater impact on biotoxicity compared to HBCDs,and more attention should be paid to the toxic effects of the river ecosystem organisms in Maoming City,Guangdong Province.This study can complement the pollution database in the study area and provide basic data for pollution control.展开更多
The purpose of this study was to examine the direct toxicity of PM2.5 collected from Beijing on human umbilical vein endothelial cells（HUVEC）. A Cell Counting Kit 8（CCK8） assay demonstrated that PM2.5 exposure dec...The purpose of this study was to examine the direct toxicity of PM2.5 collected from Beijing on human umbilical vein endothelial cells（HUVEC）. A Cell Counting Kit 8（CCK8） assay demonstrated that PM2.5 exposure decreased the proliferation of HUVECs in a dosedependent manner. We also found that PM2.5 exposure induced autophagy in HUVECs, as evidenced by：（1） an increased number of double-membrane vesicles;（2） enhanced conversion and punctuation of the microtubule-associated protein light chain 3（LC3）; and（3） decreased levels of the selective autophagy substrate p62 in a time-dependent manner.Furthermore, promoting autophagy in PM2.5-exposed HUVECs with rapamycin increased the cell survival rate, whereas inhibiting autophagy via 3-methyladenine significantly decreased cell survival. These results demonstrate that PM2.5 exposure can induce cytotoxicity and autophagy in HUVECs and that autophagy play a protective role against PM2.5-induced cytotoxicity. The findings of the present study imply a direct toxic effect of PM2.5 on HUVECs and provide novel insight into the mechanism of cardiovascular diseases caused by PM2.5 exposure.展开更多
Grass carp（Ctenopharyngodon idella） is one of the most important species in China.Decabromodiphenyl ethane（DBDPE） is a brominated flame retardant that has been used widely in industry, and has been observed to acc...Grass carp（Ctenopharyngodon idella） is one of the most important species in China.Decabromodiphenyl ethane（DBDPE） is a brominated flame retardant that has been used widely in industry, and has been observed to accumulate in the tissues of fish from South China. Evidence has shown that DBDPE is toxic to aquatic animals, but the molecular response has been unclear. MicroRNAs（miRNAs） are small noncoding and negative regulatory RNAs that are 20–24 nucleotides in length, which are involved in a wide range of biological processes. We took advantage of deep-sequencing techniques to accurately and comprehensively profile the kidney mi RNA expression of grass carp after 8 weeks of oral exposure to DBDPE. After mapping sequencing data to the genome and Expressed Sequence Tags（ESTs） of grass carp, we identified 493 miRNAs in the sequenced grass carp samples, which included 51 new miRNAs. The results indicated that 5 miRNAs were significantly down-regulated and 36 miRNAs were significantly up-regulated（FDR 〈 0.001,1.5-fold change） after DBDPE exposure. Real-time quantitative PCR（RT-qPCR） was performed on 4 miRNAs from the two samples, and the sequencing and RT-qPCR data were consistent. This study provides the first comprehensive identification of grass carp miRNAs, and the first expression analysis of grass carp miRNAs following DBDPE exposure.The results indicated that miRNAs have potential for use as biomarkers.展开更多
Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of ...Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of four dominant psammophytic shrub species occurring in different environments was studied in the semi-arid areas of Inner Mongolian grasslands. Seedlings of Hedysarum laeve, Caragana korshinskii, Artemisia sphaerocephala and Artemisia ordosica were grown under four air temperature regimes （night/day： 12.5/22.5℃, 15/25℃, 17.5/27.5℃ and 20/30℃） within climate （air temperature and humidity） controlled, naturally lit glasshouses with a night/day relative humidity of 70%/50%. Pots were watered to field capacity for each temperature treatment. Soil water condition was monitored by weighting each pot every day using an electronic balance. Date of seedling death for each treatment was recorded and the dead plants were harvested. Plant dry weights were determined after oven drying at 80℃ for 3 days. Two Artemisia species had higher growth rates than H. laeve and C. korshinskii, and the growth of all four species increased with increasing temperatures. The two Artemisia species had the highest leaf biomass increment, followed by C. korshinskii, and then H. laeve. Shoot biomass increment was higher for A. ordosica and C. korshinskii, intermediate for A. sphaerocephala and lowest for H. laeve. C. korshinskii had the highest root biomass increment. The final soil water content at death for all four species varied from 1% to 2%. C. korshinskii, A. sphaerocephala, H. laeve and A. ordosica survived for 25-43, 24-41, 26-41 and 24-37 days without watering, respectively. C. korshinskii, A. sphaerocephala, H. Laeve, and A. ordosica seedlings survived longer at the lowest temperatures （12.5/22.5℃） than at the highest temperatures （20/30℃） by 18, 17, 15 and 13 days, respectively. Increased climatic temperatures induce the death of seedlings in years with long intervals between rainfall events. The adaptation of seedlings to droughts should be emphasized in revegetation efforts in the Ordos Plateau, Inner Mongolia.展开更多
Informal electronic-waste(e-waste)recycling sites pose substantial health risks to surrounding environments and populations,yet they are not properly regulated.In this study,the soil levels of copper,lead,cadmium,eigh...Informal electronic-waste(e-waste)recycling sites pose substantial health risks to surrounding environments and populations,yet they are not properly regulated.In this study,the soil levels of copper,lead,cadmium,eight polybrominated diphenyl ethers(PBDEs),and 18 polychlorinated dibenzo-dioxins/furans(PCDD/Fs)were measured at two e-waste recycling sites in South China between 2014 and 2019.Both sites have been abandoned for natural restoration.Our results indicate that the mean Cd and PCDD/F levels at Site A in 2019 were higher than those recommended by current safety guidelines.Meanwhile,the highest exposure among children was 1.36×10^(−2)mg/(kg·d)for Cu,followed by 5.05×10^(−3)mg/(kg·d)for Pb,9.71 ng/(kg·d)for PBDEs,and 6.82 ng TEQ/(kg·d)for PCDD/Fs.Children were at elevated risk for health problem posed by Pb and Cu exposure at both sites(hazard quotient>1)and by PCDD/Fs at Site A.Further risk assessment was conducted on the target organs and endpoints of heavy metals and PCDD/Fs.The hazard index(HI)for the target organ mixed-risk of heavy metals was high(HI=1.27),as was that of PCDD/Fs(HI=1.66),which can disrupt endocrine function and pose a risk of reproductive toxicity in children.Owing to incomplete cleaning,contaminants persist in soils over long periods and may harm nearby environments and communities.Our study demonstrates that heavy metal,PBDE,and PCDD/F contamination have not yet been remediated,and intervention is needed to reduce pollution and associated risks in areas affected by e-waste.展开更多
Introduction:This study introduces a novel method for developing an advanced exposure conceptual model tailored for health risk assessment,focusing on microenvironments.Methods:The research was conducted at a major sm...Introduction:This study introduces a novel method for developing an advanced exposure conceptual model tailored for health risk assessment,focusing on microenvironments.Methods:The research was conducted at a major smelter in China to assess the health risks associated with trace metals(TMs)pollutants in the facility and the surrounding soil.Results:Deterministic risk assessment indicated that cobalt,cadmium,antimony,manganese,arsenic,plumbum,and mercury(Co,Cd,Sb,Mn,As,Pb,and Hg)necessitated further evaluation through probabilistic risk assessment to assess potential health risks to residents.The 95%quantile concentrations of other TMs were found to be within acceptable health risk limits.For the probabilistic risk assessment,exposure parameters such as body weight,respiration rate,and exposure duration were collected using a questionnaire.This targeted assessment of the residential microenvironment revealed it as the site of the highest carcinogenic(CR)and non-carcinogenic risks(NCR),with values ranging from 2.84×10-5 to 6.7×10-5 and 1.59 to 5.57,respectively.Conclusion:The primary contaminants posing the greatest health risks in residential and industrial areas have been identified as As,Pb,and Mn.The probabilistic health risk model,which focuses on microenvironmental factors,yields more precise results and offers a valuable tool for managing soil health risks.展开更多
基金supported by the StrategicPriority Research Program of the Chinese Academy of Sciences(No.XDA28010501)the National Natural Science Foundation of China(Nos.22176193 and U21A20293)the Science Foundation of the Chinese Academy of Sciences(No.ISSAS2422).
文摘Silica(SiO_(2))nanoparticles(nSiO_(2))have attracted considerable attention in agricultural practices.However,their effects on polycyclic aromatic hydrocarbon(PAH)accumulation in plants remain largely unknown.Thus,this issue was tracked here with a 30-d pot experiment with foliar spraying of 30 and 100 nm SiO_(2) particles(100 mg L-1,10 mL)on Amaranthus tricolor L.(amaranth).Compared with foliar spraying of ultrapure water(i.e.,the control),foliar spraying of nSiO_(2) increased phenanthrene(PHE)contents in amaranth leaves by 242%±88.4%and 158%±29.6%,respectively,and the increases were significantly higher than that by foliar spraying of 2μm particles(96.0%±29.2%).Metabolomics analysis indicated that compared to nSiO_(2),2μm SiO_(2) significantly boosted oxidative defense in amaranth leaves,enhanced cell membrane fluidity,and upregulated amino acid metabolism,glycolysis,and gluconeogenesis.In addition,the upregulation of discriminating metabolites was the most significant in the 2μm SiO_(2) treatment,followed by the 100 and 30 nm nSiO_(2) treatments.This is mainly because nSiO_(2) promoted amaranth growth and decreased average PHE content per unit biomass,namely dilute effect.Thus,slighter metabolic disturbances were observed in the 30 and 100 nm SiO_(2) treatments compared with the control and 2μm SiO_(2) treatment.This study revealed the possibility of PAH accumulation enhancement in vegetables with foliar spraying of nSiO_(2).The results of this study provide theoretical guidance regarding particle size selection for the safe agricultural application of SiO_(2) in PAH-contaminated areas.
基金supported by the National Key Research and Development Program of China(Nos.2022YFC3902100 and 2023YFC3905203)the National Natural Science Foundation of China(Nos.42377438 and 82103799)+1 种基金the Central Publicinterest Scientific Institution Basal Research Fund of South China Institute of Environmental Sciences,MEE(No.PMzx703–202305–183)the Fund of State Environmental Protection Key Laboratory of Radiation Environment&Health(2022).
文摘Diabetes and impaired fasting glucose(IFG)are significant global health concerns.However,the potential effects of mixed heavy metal exposure on these conditions remain underexplored.This study aims to investigate the combined effects of multiple metals on diabetes risk and explore the mediating role of BodyMass Index(BMI)in rural China.Across-sectional analysis involved 2313 adults from 12 provinces in rural China.Urinary levels of zinc(Zn),chromium(Cr),nickel(Ni),cadmium(Cd),and lead(Pb)were quantified using inductively coupled plasma mass spectrometry.Fasting blood glucose(FBG)levels were measured with an automatic biochemical analyzer.Logistic regression models and the Bayesian Kernel Machine Regression(BKMR)model were used to examine associations and interactions.Mediation analysis was performed to assess the role of BMI.The results of our study indicate that there is a significant association between urinary Zn(OR=2.38,95%CI:1.57,3.60),Cr(OR=1.24,95%CI:1.31,1.61),and Ni(OR=1.51,95%CI:1.05,2.18)and the diabetes risk.The study revealed that exposure to Ni amplified the associations between Zn,Cr and diabetes/IFG risk.Additionally,BMI was identified as a significant mediator in the relationship between metal exposure,particularly Cr/Cd,and diabetes risk.These findings reveal a complex link between multiple metals,such as Zn,Cr,and Ni,and diabetes risk,and emphasize the potential opposite mediating effects of BMI in different metal-induced diabetes mechanisms.Further investigation of these mechanisms is warranted.
基金supported by the National Natural Science Foundation of China (No.42177420)。
文摘Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.
基金supported by the National Key Research and Development Program of China(Nos.2022YFC3902102 and 2019YFC1803403)the Key Programof National Natural Science Foundation of China(No.41931298).
文摘Sediment is the ultimate sink of environmental pollutants.A total of 128 surface sediment sampleswere collected from8 rivers and 3 reservoirs in Maoming City,Guangdong Province.This study assessed the content and distribution of brominated flame retardants in sediments.The acute toxicity effects of tetrabromobisphenol A(TBBPA)and hexabromocyclododecane(HBCDs)in sediments were evaluated using Caenorhabditis elegans as model organisms.The concentration of TBBPA in sediments ranged from not detected(ND)to 12.59μg/kg andwas mainly distributed in the central area,whichwas affected by the emission of TBBPA from residential and factory.The concentration of HBCDs ranged from ND to 6.31μg/kg,and the diastereoisomer distribution was consistent,showing a trend close to the South China Sea.The composition pattern of HBCDs in the surface sediments from rivers were 41.73%-62.33%,7.89%-25.54%,and 18.76%-40.65%forα-,β-,andγ-HBCD,respectively,and in the sediments from reservoirs were 26.15%-45.52%,7.44%-19.23%,and 47.04%-61.89%forα-,β-,andγ-HBCD,respectively.When the sum of concentrations of TBBPA and HBCD in sediments were above high levels,reactive oxygen species in nematodes significantly increased,resulting in an oxidative stress response.Intestinal permeabilitywas also enhanced,causing intestinal damage.In addition,in terms of this study,TBBPA had a greater impact on biotoxicity compared to HBCDs,and more attention should be paid to the toxic effects of the river ecosystem organisms in Maoming City,Guangdong Province.This study can complement the pollution database in the study area and provide basic data for pollution control.
基金supported by the National Natural Science Foundation of China (Nos. 21677006, 21177119)the State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences (No. SKLECRA2016OFP)the State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (No. KF2015-19)
文摘The purpose of this study was to examine the direct toxicity of PM2.5 collected from Beijing on human umbilical vein endothelial cells（HUVEC）. A Cell Counting Kit 8（CCK8） assay demonstrated that PM2.5 exposure decreased the proliferation of HUVECs in a dosedependent manner. We also found that PM2.5 exposure induced autophagy in HUVECs, as evidenced by：（1） an increased number of double-membrane vesicles;（2） enhanced conversion and punctuation of the microtubule-associated protein light chain 3（LC3）; and（3） decreased levels of the selective autophagy substrate p62 in a time-dependent manner.Furthermore, promoting autophagy in PM2.5-exposed HUVECs with rapamycin increased the cell survival rate, whereas inhibiting autophagy via 3-methyladenine significantly decreased cell survival. These results demonstrate that PM2.5 exposure can induce cytotoxicity and autophagy in HUVECs and that autophagy play a protective role against PM2.5-induced cytotoxicity. The findings of the present study imply a direct toxic effect of PM2.5 on HUVECs and provide novel insight into the mechanism of cardiovascular diseases caused by PM2.5 exposure.
基金financially supported by a General Project granted by the National Natural Science Foundation of China (No. 51178002)
文摘Grass carp（Ctenopharyngodon idella） is one of the most important species in China.Decabromodiphenyl ethane（DBDPE） is a brominated flame retardant that has been used widely in industry, and has been observed to accumulate in the tissues of fish from South China. Evidence has shown that DBDPE is toxic to aquatic animals, but the molecular response has been unclear. MicroRNAs（miRNAs） are small noncoding and negative regulatory RNAs that are 20–24 nucleotides in length, which are involved in a wide range of biological processes. We took advantage of deep-sequencing techniques to accurately and comprehensively profile the kidney mi RNA expression of grass carp after 8 weeks of oral exposure to DBDPE. After mapping sequencing data to the genome and Expressed Sequence Tags（ESTs） of grass carp, we identified 493 miRNAs in the sequenced grass carp samples, which included 51 new miRNAs. The results indicated that 5 miRNAs were significantly down-regulated and 36 miRNAs were significantly up-regulated（FDR 〈 0.001,1.5-fold change） after DBDPE exposure. Real-time quantitative PCR（RT-qPCR） was performed on 4 miRNAs from the two samples, and the sequencing and RT-qPCR data were consistent. This study provides the first comprehensive identification of grass carp miRNAs, and the first expression analysis of grass carp miRNAs following DBDPE exposure.The results indicated that miRNAs have potential for use as biomarkers.
基金supported by the National Basic Research Program of China (2009CB825103)
文摘Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of four dominant psammophytic shrub species occurring in different environments was studied in the semi-arid areas of Inner Mongolian grasslands. Seedlings of Hedysarum laeve, Caragana korshinskii, Artemisia sphaerocephala and Artemisia ordosica were grown under four air temperature regimes （night/day： 12.5/22.5℃, 15/25℃, 17.5/27.5℃ and 20/30℃） within climate （air temperature and humidity） controlled, naturally lit glasshouses with a night/day relative humidity of 70%/50%. Pots were watered to field capacity for each temperature treatment. Soil water condition was monitored by weighting each pot every day using an electronic balance. Date of seedling death for each treatment was recorded and the dead plants were harvested. Plant dry weights were determined after oven drying at 80℃ for 3 days. Two Artemisia species had higher growth rates than H. laeve and C. korshinskii, and the growth of all four species increased with increasing temperatures. The two Artemisia species had the highest leaf biomass increment, followed by C. korshinskii, and then H. laeve. Shoot biomass increment was higher for A. ordosica and C. korshinskii, intermediate for A. sphaerocephala and lowest for H. laeve. C. korshinskii had the highest root biomass increment. The final soil water content at death for all four species varied from 1% to 2%. C. korshinskii, A. sphaerocephala, H. laeve and A. ordosica survived for 25-43, 24-41, 26-41 and 24-37 days without watering, respectively. C. korshinskii, A. sphaerocephala, H. Laeve, and A. ordosica seedlings survived longer at the lowest temperatures （12.5/22.5℃） than at the highest temperatures （20/30℃） by 18, 17, 15 and 13 days, respectively. Increased climatic temperatures induce the death of seedlings in years with long intervals between rainfall events. The adaptation of seedlings to droughts should be emphasized in revegetation efforts in the Ordos Plateau, Inner Mongolia.
基金the National Key R&D Program of China(Nos.2018YFC1800304 and 2019YFC1805504).
文摘Informal electronic-waste(e-waste)recycling sites pose substantial health risks to surrounding environments and populations,yet they are not properly regulated.In this study,the soil levels of copper,lead,cadmium,eight polybrominated diphenyl ethers(PBDEs),and 18 polychlorinated dibenzo-dioxins/furans(PCDD/Fs)were measured at two e-waste recycling sites in South China between 2014 and 2019.Both sites have been abandoned for natural restoration.Our results indicate that the mean Cd and PCDD/F levels at Site A in 2019 were higher than those recommended by current safety guidelines.Meanwhile,the highest exposure among children was 1.36×10^(−2)mg/(kg·d)for Cu,followed by 5.05×10^(−3)mg/(kg·d)for Pb,9.71 ng/(kg·d)for PBDEs,and 6.82 ng TEQ/(kg·d)for PCDD/Fs.Children were at elevated risk for health problem posed by Pb and Cu exposure at both sites(hazard quotient>1)and by PCDD/Fs at Site A.Further risk assessment was conducted on the target organs and endpoints of heavy metals and PCDD/Fs.The hazard index(HI)for the target organ mixed-risk of heavy metals was high(HI=1.27),as was that of PCDD/Fs(HI=1.66),which can disrupt endocrine function and pose a risk of reproductive toxicity in children.Owing to incomplete cleaning,contaminants persist in soils over long periods and may harm nearby environments and communities.Our study demonstrates that heavy metal,PBDE,and PCDD/F contamination have not yet been remediated,and intervention is needed to reduce pollution and associated risks in areas affected by e-waste.
文摘Introduction:This study introduces a novel method for developing an advanced exposure conceptual model tailored for health risk assessment,focusing on microenvironments.Methods:The research was conducted at a major smelter in China to assess the health risks associated with trace metals(TMs)pollutants in the facility and the surrounding soil.Results:Deterministic risk assessment indicated that cobalt,cadmium,antimony,manganese,arsenic,plumbum,and mercury(Co,Cd,Sb,Mn,As,Pb,and Hg)necessitated further evaluation through probabilistic risk assessment to assess potential health risks to residents.The 95%quantile concentrations of other TMs were found to be within acceptable health risk limits.For the probabilistic risk assessment,exposure parameters such as body weight,respiration rate,and exposure duration were collected using a questionnaire.This targeted assessment of the residential microenvironment revealed it as the site of the highest carcinogenic(CR)and non-carcinogenic risks(NCR),with values ranging from 2.84×10-5 to 6.7×10-5 and 1.59 to 5.57,respectively.Conclusion:The primary contaminants posing the greatest health risks in residential and industrial areas have been identified as As,Pb,and Mn.The probabilistic health risk model,which focuses on microenvironmental factors,yields more precise results and offers a valuable tool for managing soil health risks.
