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1.
Ecotoxicol Environ Saf ; 194: 110442, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171121

RESUMO

In recent decades, indoor air quality (IAQ) has become one of the most important human health issues. The potential properties and potential health hazards of polycyclic aromatic hydrocarbons (PAHs) are associated with their long-term residues, bioaccumulation and semivolatility, and they can also be transferred through a variety of media, such as the atmosphere, water and soil. Dust particles from indoor and outdoor emission sources adhere to A-C filters and can represent air quality to a certain extent. However, few studies have focused on PAHs in A-C filter dust in Hefei, China. In this study, 16 PAHs were selected, dust samples were collected from A-C filters from three different functional districts, and GC-MS analysis of the samples was performed. The concentration of the ∑16PAHs ranged from 7.34 to 326.84 µg g-1, 5.07-15.34 µg g-1, 4.09-47.26 µg g-1 and 0.97-13.38 µg g-1 in dust samples from the Administrative District (AD), Industrial District (ID), Commercial District (CD) and Outdoors (OD), respectively. The total PAH concentration in A-C dust was much higher than that in dust deposited outdoors in the urban area. The percentage of 5-6 ring PAHs accounted for more than 70% of the ∑16PAHs, which shows that the PAHs in A-C dust mainly come from pyrolysis rather than a diagenetic source. Principal component analysis (PCA) and diagnostic ratios were used in a source analysis, and the results indicated that the main PAHs emission sources in the different functional districts were coal, wood and biomass combustion. The incremental lifetime cancer risk (ILCR) values indicated a medium to high potential carcinogenic risk for adults and children exposed to dust with PAHs. Particularly, skin contact and ingestion of carcinogenic PAHs from dust are the major exposure pathways and present an exposure risk that is four to five orders of magnitude higher than the risk of inhalation.

2.
Ecotoxicol Environ Saf ; 191: 110244, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004946

RESUMO

The purpose of this research was to examine the influence of hydrothermally treated coal gangue (HTCG) with and without biochar (BC) on the leaching, bioavailability, and redistribution of chemical fractions of heavy metals (HMs) in copper mine tailing (Cu-MT). An increase in pH, water holding capacity (WHC) and soil organic carbon (SOC) were observed due to the addition of BC in combination with raw coal gangue (RCG) and HTCG. A high Cu and other HMs concentration in pore water (PW) and amended Cu-MT were reduced by the combination of BC with RCG and/or HTCG, whereas individual application of RCG slightly increased the Cu, Cd, and Zn leaching and bioavailability, compared to the unamended Cu-MT. Sequential extractions results showed a reduction in the exchangeable fraction of Cu, Cd, Pb, and Zn and elevation in the residual fraction following the addition of BC-2% and BC-HTCG. However, individual application of RCG slightly increased the Cu, Cd, and Zn exchangeable fractions assessed by chemical extraction method. Rapeseed was grown for the following 45 days during which physiological parameters, metal uptake transfer rate (TR), bioconcentration factor (BCF), and translocation factor (TF) were measured after harvesting. In the case of plant biomass, no significant difference between applied amendments was observed for the fresh biomass (FBM) and dry biomass (DBM) of shoots and roots of rapeseed. However, BC-2% and BC-HTCG presented the lowest HMs uptake, TR, BCF (BCFroot and BCFshoot), and TF for Cu, Cd, Cr, Ni, Pb, and Zn in rapeseed among the other amendments compared to the unamended Cu-MT. Overall, these findings are indicative that using biochar in combination with RCG and/or HTCG led to a larger reduction in HMs leaching and bioavailability, due to their higher sorption capacity and could be a suitable remediation strategy for heavy metals in a Cu-MT.

3.
Anticancer Drugs ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32011366

RESUMO

OBJECTIVE: Tanshinone I, one of the components of Salvia miltiorrhiza Bunge, exhibits anti-tumor ability and induces autophagy. But the mechanisms are not fully understood. This study aims to investigate whether AMP-activated protein kinase dependent pathway is involved in the autophagic signaling regulation and its relationship with tumor suppression. METHODS: Breast cancer cells (MDA-MB-231, MCF-7) and hepatocellular carcinoma cells (HepG2) were treated with Tanshinone I or vehicle. Acridine orange dyeing and transmission electron microscopy were employed to evaluate autophagic cells. MTT and Cell Counting Kit-8 assays were used to detect the effect of Tanshinone I combined with autophagy inhibitors on cell proliferation. Western blot was used to detect the expression levels of Beclin1 and LC3-I/II, as well as the phosphorylation of AMPKα and ULK1. RESULTS: Our results showed that Tanshinone I suppressed proliferation of HepG2, MDA-MB-231 and MCF-7 cancer cell lines. LC3-II and P62 were induced by Tanshinone I in all three cancer cell lines. But autophagic flux analysis showed that Tanshinone I treatment induced autophagy only in MDA-MB-231, which was also proved by transmission electron microscopy. Tanshinone I upregulated the phosphorylation of AMPKα and its downstream ULK1. AMP-activated protein kinase inhibitor compound C attenuated Beclin 1 and LC3-II expression induced by Tanshinone I in HepG2. In MDA-MB-231, compound C surprisingly induced LC3-II upregulation which is independent of AMPKα activation. Under this circumstance, treatment of Tanshinone I combined with compound C significantly inhibited MDA-MB-231 proliferation, compared with Tanshinone I treatment alone. CONCLUSION: This study demonstrates that Tanshinone I could induce cancer cell death and regulate autophagy signaling in breast cancer and hepatic carcinoma cells. Activation of AMPKα was found to be involved in autophagic signaling regulation by Tanshinone I.

4.
Arch Environ Contam Toxicol ; 78(3): 392-400, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31932858

RESUMO

Volatile organic compounds (VOCs) are involved in the formation of ozone formation, which plays a significant role in regional air contamination and poses a great threat to human health. The VOCs were collected from the urban area of Hefei city via an off-line sampling method (SUMMA canister) and determined by gas chromatography-mass spectrometer. The average concentrations of VOCs were 17.65 ± 28.36 ppbv, which were mainly contributed by aromatics (10.02 ± 13.37 ppbv), haloalkane (5.37 ± 8.90 ppbv), ally halide (1.25 ± 3.36 ppbv), and aryl halid (1.02 ± 2.73 ppbv). According to the principal component analysis, three major sources were identified, including solvent use, vehicle exhaust, and industrial release, accounting for 70.6% of the total variance of the data. Health risk assessment was utilized to evaluate the potential adverse health effects of the individual VOC. The total hazard ratio in the selected area was higher than 1, where could pose health threat to exposed population. The cancer risk for benzene, carbon tetrachloride, trichloromethane, and 1, 2-dichloroethane were 4.8 × 10-5, 4.5 × 10-5, 3.3 × 10-5, and 2.5 × 10-5, respectively, indicating definite health risks.

5.
Sci Total Environ ; 710: 135599, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31784146

RESUMO

Dust on air conditioning filters can represent the re-suspended particulate matter in indoor air, which may pose potential health risks to humans. However, source identification and influence factors of indoor dust are controversial. The present study investigated the distribution of Cd, Cr, Mn, Ni, Pb, Sb, V, and Zn, as well as stable carbon isotope, in indoor dust from three different functional zones in Hefei to discuss the sources and influence factors of indoor dust. PCA analysis of heavy metals showed that indoor sources (such as cooking and smoking) were the main sources. Negative correlation appeared between family size and heavy metal concentrations. This was because people acted as a sink of pollutants. Concentration analysis of heavy metals revealed that smoking and cooking had weak relevance with heavy metal concentrations. While through the δ13C analysis, cooking had a significant correlation with δ13C of indoor dust, instructing that cooking was a significant source of indoor dust. Besides, smoking also had a certain correlation with δ13C of indoor dust, instructing that smoking was one of the sources of indoor dust.

6.
Ecotoxicol Environ Saf ; 190: 110059, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837569

RESUMO

Toxic metal pollution is a renowned environmental concern, especially to sensitive environments like school classrooms and their association with children's health. The study was planned to determine the pollution characteristics of 13 potentially toxic metal (oid)s (PTMs) and their associated children's health risk assessment from school dust samples of considerably three land-use types (residential, roadside, and industrial areas) of Lahore, Pakistan. Geo-accumulation (Igeo), pollution (PI), integrated pollution (IPI) and pollution load (PLI) indexes were used to determine the PTMs contamination and USEPA health risk assessment models were employed to assess the health risks in children. The mean concentrations of Cd, Cr, Cu, Ni, Pb, and Zn for three land-use types were found much higher than the permissible limits. Results of pollution indices revealed that school dust was strongly contaminated with Cd, Pb, and Zn whilst moderately contaminated with Cr and Cu. Moreover, the health risk assessment models revealed no significant non-cancerous risks in children with predominantly highest hazardous index (HI) of Cr in industrial (4.61E-01) and Pb in both roadside (4.30E-01) and residential (2.26E-01) area schools. According to cumulative HI of all PTMs and exposure routes, the land-use areas were in descending order as industrial > roadside > residential. The calculations of hazardous quotient (HQ) showed ingestion was the leading pathway of PTMs exposure through school dust. For carcinogenic health risk (CR), the most prominent PTM was Cr with values of 1.53E-06 in industrial area schools, found close to the tolerable range (1.0E-06). Hence, school dust of Lahore prominently contaminated with eminent PTMs triggering slight health risks predominantly by ingestion exposure to children.

7.
Sci Total Environ ; 719: 135658, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874752

RESUMO

Lead (Pb) is a non-essential and extremely noxious metallic-element whose biogeochemical cycle has been influenced predominantly by increasing human activities to a great extent. The introduction and enrichment of this ubiquitous contaminant in the terrestrial-environment has a long history and getting more attention due to its adverse health effects to living organisms even at very low exposure levels. Its lethal-effects can vary widely depending on the atmospheric-depositions, fates and distribution of Pb isotopes (i.e., 204Pb, 206Pb, 207Pb &208Pb) in the terrestrial-environment. Thus, it is essential to understand the depositional behavior and transformation mechanism of Pb and the factors affecting Pb isotopes composition in the terrestrial-compartments. Owing to the persistence nature of Pb-isotopic fractions, regardless of ongoing biogeochemical-processes taking place in soils and in other interlinked terrestrial-compartments of the biosphere makes Pb isotope ratios (Pb-IRs) more recognizable as a powerful and an efficient-tool for tracing the source(s) and helped uncover pertinent migration and transformation processes. This review discusses the ongoing developments in tracing migration pathway and distribution of lead in various terrestrial-compartments and investigates the processes regulating the Pb isotope geochemistry taking into account the source identification of lead, its transformation among miscellaneous terrestrial-compartments and detoxification mechanism in soil-plant system. Additionally, this compendium reveals that Pb-pools in various terrestrial-compartments differ in Pb isotopic fractionations. In order to improve understanding of partition behaviors and biogeochemical pathways of Pb isotope in the terrestrial environment, future works should involve investigation of changes in Pb isotopic compositions during weathering processes and atmospheric-biological sub-cycles.

8.
Chemosphere ; 240: 124845, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31561162

RESUMO

In the paper, hydrothermally (HT) treated, sulfuric acid (H2SO4), and hydrochloric acid (HCl) washed fly ashes (FA) were used to examine the applied effects with and without biochar (BC) on the bioavailability of heavy metals (HMs) and growth of maize (Zea mays L.) plants in coal-mining contaminated soil. Addition of BC in combination with these processed fly ashes (PFA) significantly increased the soil pH, EC, and soil organic carbon (SOC). Individual application of BC and PFA increased the available contents of Mg, Mn, and Fe, while the combination of BC and PFA significantly decreased the bioavailability of HMs in soil compared to control. The BC + HT-FA and BC + H2SO4-FA were most efficient treatments followed by BC + HCl-FA in promoting plant growth parameters (i.e., fresh and dry biomass, root and shoot lengths), reduction in the uptake of HMs and increase in the uptake of macronutrients. The results established that the combined application of BC and PFA synergistically increased HMs immobilization and maize biomass yields. The lowest transfer rate (TR), bioconcentration factor (BCF), and translocation factor (TF) for Cr, Co, Ni, Cu, Zn, Cd, and Pb were detected in BC + HT-FA, followed by BC + H2SO4-FA and BC + HCl-FA treatments after 60 days of maize crop harvesting. It could be suggested that using BC along with PFA as a soil stabilizer may be a promising source to immobilize HMs in a coal-mining contaminated soil.


Assuntos
Carvão Vegetal/química , Cinza de Carvão/química , Minas de Carvão/métodos , Poluição Ambiental/efeitos adversos , Metais Pesados/química , Poluentes do Solo/química , Solo/química , Zea mays/química , Disponibilidade Biológica
9.
Ecotoxicol Environ Saf ; 187: 109845, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31654865

RESUMO

The extensive use of nano-fabricated products in daily life is releasing a large volume of engineered nanoparticles (ENPs) in the environment having unknown consequences. Meanwhile, little efforts have been paid to immobilize and prevent the entry of these emerging contaminants in the food chain through plant uptake. Herein, we investigated the biochar role in cerium oxide nanoparticles (CeO2NPs) bioaccumulation and subsequent translocation in wheat (Triticum aestivum L.) as well as impact on growth, photosynthesis and gas-exchange related physiological parameters. Results indicated that CeO2NPs up to 500 mg L-1 level promoted the plant growth by triggering photosynthesis, transpiration and stomatal conductance. Higher NPs concentration (2000 mg CeO2NPs L-1) has negatively affected the plant growth and photosynthesis related processes. Conversely, biochar amendment with CeO2NPs considerably reduced (~9 folds) the plants accumulated contents of Ce even at 2000 mg L-1 exposure level of CeO2NPs through surface complexation process and alleviated the phyto-toxic effects of NPs on plant growth. XPS and FTIR analysis confirmed the role of biochar-mediated carboxylate and hydroxyl groups bonding with CeO2NPs. These findings provides an inside mechanistic understanding about biochar interaction with nano-pollutants to inhibit their bioavailability to plant body.


Assuntos
Cério/análise , Carvão Vegetal/química , Nanopartículas/análise , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/análise , Triticum/efeitos dos fármacos , Disponibilidade Biológica , Cério/metabolismo , Recuperação e Remediação Ambiental/métodos , Nanopartículas/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Triticum/metabolismo
10.
Huan Jing Ke Xue ; 40(8): 3415-3420, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854745

RESUMO

Through the collection of atmospheric PM2.5 and PM10 samples in Hefei in 2018, combined with high-precision testing of elements in these samples, the elemental composition of PM2.5 and PM10 was studied during heavy pollution episodes and under non-pollution conditions. The main pollutant sources and causes of heavy pollution in Hefei are also discussed based on an analysis of the differences in the element composition of atmospheric particles. The results showed that, among the 16 elements detected, the mass concentrations of Si, Al, Mg, and Ca during heavy pollution episodes were lower than during non-polluted conditions. This may have been caused by a reduction in ground dust emission caused by calmer winds during heavily polluted conditions. In comparison, the mass concentrations of S, Na, K, Cl, Ti, Fe, P, Cu, and Ni were higher during heavy pollution episodes than during non-pollution conditions, and the difference was greatest for S. The proportion and enrichment factors for S were also greatly increased during heavy pollution events, indicating that its emission from coal burning is the main source of pollution in Hefei. The heavy metal content was low, however, and the enrichment factor was high, the main sources of which may be garbage incineration, motor vehicles, and industrial emissions.

11.
Environ Monit Assess ; 191(12): 748, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31724064

RESUMO

The Indus Basin Irrigation Network (IBIN) plays a vital role in the agricultural system of Pakistan, irrigating seventeen million hectares of cultivated areas. Rapid urbanization, industrialization, and agricultural activities along the Indus basin have influenced the soil quality and human health; it is, therefore, critical to know its pollution characteristics. Soil samples from Indus basin, i.e., Abbottabad (ABT), Haripur (HRP), Attock (ATC), and Islamabad (ISB) have been analyzed for the total contents of potentially toxic metal(loid)s (PTMs) in the top layer. The topsoil samples from 0 to 10 cm depth have been further investigated using different pollution indices and human health risk assessment models. The contamination degree of soil pollution was highest in ISB (33.75), followed by ABT (25.30) and ATC (23.57). The assessment of the daily intake of PTMs by children and adults through different pathways revealed ingestion as the significant exposure pathway. Cr was found to be the major element posing non-carcinogenic health risks to children at ATC whereas the non-carcinogenic risks posed by all other PTMs were within the safe limit. Furthermore, life-time carcinogenic risks for Ni followed by Cr and Cd were greatly exceeded at all locations and As at ATC and ISB for both age groups, but comparatively children were found to be at a higher risk of carcinogenicity. Hence, efficient remediation strategies are needed to reduce the increasing content and health risks of PTMs in the Indus basin.


Assuntos
Monitoramento Ambiental , Poluição Ambiental/estatística & dados numéricos , Metais Pesados/análise , Poluentes do Solo/análise , Adulto , Criança , Poluição Ambiental/análise , Humanos , Paquistão , Medição de Risco , Solo
12.
Environ Sci Pollut Res Int ; 26(34): 35094-35106, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679141

RESUMO

The surface soils were collected from four areas in the Yellow River Delta (YRD), including three functional areas in the natural reserve of the YRD (the core area, buffer area, and experimental area) and a neighboring area of the natural reserve. The total concentrations, speciations, contamination status, and health risk assessments of the mercury (Hg) and arsenic (As) in surface soils of the YRD were investigated. The average Hg concentration was about three times that of the background value, while As was just slightly higher than the background. Hg levels in the sites of experimental area were significantly higher than those in the core area and buffer area, which was consistent with the human activity intensities of the three functional areas. However, no significant differences of As levels were observed across different areas. According to the sequential extraction experiments, only less than 5% of Hg and As were associated with the exchangeable fraction, while over 80% of them were found in the residual fraction, indicating low mobility and bioavailability of both Hg and As. The soil contamination status assessments suggested a "good state," and the health risk assessments indicated a "low risk" of Hg and As in the soils of YRD.


Assuntos
Arsênico/análise , Monitoramento Ambiental , Mercúrio/análise , Poluentes do Solo/análise , China , Humanos , Medição de Risco , Rios , Solo
13.
Int J Phytoremediation ; 21(13): 1290-1295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31633378

RESUMO

To evaluate the phytoextraction efficiency of Gypsophila paniculata from Cs-contaminated soils and analyze the mechanism of Cs accumulation in G. paniculata, we analyzed the characteristics of Cs bioaccumulation and subcellular distribution, in addition to its chemical forms in the plant under hydroponic conditions. The results showed that total Cs content in the aboveground parts and the entire plant were as high as 6137.32 mg·kg-1 dry weight and 7338.49 mg·kg-1 dry weight, respectively, after 17 days in the 50 mg·L-1 Cs treatment. The BCF was between 2.35 and 3.38. The TF was between 1.00 and 2.46 in G. paniculata. Subcellular distribution of Cs in the plant was as follows: soluble fraction > cell wall > organelles. Inorganic Cs (F-ethanol) and water-soluble Cs (F-dH2O) were the main types of Cs in G. paniculata. Further studies show that the phytoextraction efficiency can reach 10.30-11.91% planting a season of G. paniculata under potted conditions. The results suggested that G. paniculata, a perennial, drought-tolerant herb, was a high-accumulator of Cs, which may have potential uses in phytoremediation of Cs-contaminated soil.


Assuntos
Poluentes Radioativos do Solo , Poluentes do Solo , Biodegradação Ambiental , Césio , Hidroponia , Solo
14.
Arch Environ Contam Toxicol ; 77(4): 594-604, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31388704

RESUMO

A total of 39 lower brominated PBDE congeners in surface soils from the Yellow River Delta Natural Reserve (YRDNR) were analyzed in the present study. The total concentrations of PBDEs (ΣPBDEs) ranged from "not detected" to 0.732 ng g-1, with a mean concentration of 0.142 ng g-1. The concentrations of the ΣPBDEs displayed no correlation with the content of the total organic carbon in the YRDNR. The ΣPBDEs concentrations in the Experimental Area were significantly higher than that of the Buffer Area and Core Area, and ΣPBDEs in soils in the North were lower than that of the South. PentaBDEs and HexaBDEs were the most abundant homologues, and the occurrence of PBDEs in the YRDNR may be attributed to the debromination and long range transport of DecaBDEs. Even though the cancer risk and mass inventory of PBDEs in the present study area were estimated to be very low, due to the widespread presence of PBDEs and the particularity of the natural reserve, vigilance should not be let up on the issue of environmental contamination caused by these compounds despite the gradual phase out of their commercial products in the world.


Assuntos
Éteres Difenil Halogenados/análise , Poluentes do Solo/análise , Carcinógenos Ambientais/análise , Carcinógenos Ambientais/toxicidade , China , Conservação dos Recursos Naturais , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/toxicidade , Humanos , Medição de Risco , Poluentes do Solo/toxicidade
15.
Clin Chem Lab Med ; 57(12): 1923-1932, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31415235

RESUMO

Background Although laboratory information system (LIS) is widely used nowadays, the results of routine urinalysis still need 100% manual verification. We established intelligent verification criteria to perform the automated verification process and reduce manual labor. Methods A total of 4610 urine specimens were obtained from the patients of three hospitals in Beijing, China. Firstly, 895 specimens were measured to establish the reference intervals of formed-element parameters in UF5000. Secondly, 2803 specimens were analyzed for setting up the intelligent verification criteria (including the microscopic review rules and manual verification rules). Lastly, 912 specimens were used to verify the efficacy and accuracy of the intelligent verification criteria. Phase-contrast microscopes were used for the microscopic review. Results Employing a results level corresponding relationship in specific parameters including hemoglobin (red blood cell [RBC]), leukocyte esterase (white blood cell [WBC]) and protein (cast) between the dry-chemistry analysis and formed-element analysis, as well as instrument flags, we established seven WBC verification rules, eight RBC verification rules and four cast verification rules. Based on the microscopy results, through analyzing the pre-set rules mentioned earlier, we finally determined seven microscopic review rules, nine manual verification rules and three auto-verification rules. The microscopic review rate was 21.98% (616/2803), the false-negative rate was 4.32% (121/2803), the total manual verification rate was 35.71% (1001/2803) and the auto-verification rate was 64.29% (1802/2803). The validation results were consistent. Conclusions The intelligent verification criteria for urinary dry-chemistry and urinary formed-element analysis can improve the efficiency of the results verification process and ensure the reliability of the test results.

16.
Chemosphere ; 233: 440-451, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31181492

RESUMO

A combination of thermogravimetric analysis and lab-scale fixed bed combustion experiments was carried out to study the thermochemical, kinetic and heavy metals emission behavior during co-combustion of industrial coal slurry (CS) and sewage sludge (SS). The results found that the blends had integrative combustion profiles which reflected both coal slurry and sewage sludge. During co-combustion, the ignition performance of CS could be significantly improved with the addition of SS. Synergetic effects of the co-combustion were observed at lower temperature, while the high-temperature char combustion of the blends was inhibited because of high ash components of SS or formation of inactive alkali metal aluminosilicates. Kinetic analysis confirmed the improve iginition behavior of blends. Both the comprehensive combustibility index S and the activation energy suggested that the blends with 20% SS may have the best promoting effects. Compared with CS, the higher concentration of Cl in SS increased the volatilization ratios of Cu, Zn, As, and Pb. When added CS into SS, the volatilization ratios of arsenic decreased during combustion. The inhibition effects for arsenic during co-combustion might be associated with the capture of arsenic vapors by the new-formed Ca/Al from CS thermal decomposition.


Assuntos
Poluentes Atmosféricos/análise , Carvão Mineral/análise , Incineração/métodos , Metais Pesados/análise , Esgotos/química , Arsênico/análise , Cinza de Carvão/análise , Temperatura Alta , Cinética , Volatilização
17.
Environ Pollut ; 251: 839-849, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31125814

RESUMO

Metals in indoor dust pose potential health risks to humans. Dust deposition on air conditioner filters can represent the resuspended particulate matter in indoor air. However, few studies have examined this until now. This study investigated the total concentrations and different chemical fractionations of Cd, Cr, Mn, Ni, Pb, Sb, V, and Zn in indoor dust from three different functional zones (the Chief District, Commercial District (CmD), and Industrial District) in Hefei. The mean metal concentrations in indoor dust decreased in the following order: Zn > Mn > Pb > Cr > Ni > V > Cd > Sb. Cd, Pb, and Zn mainly existed in the mobile fraction. Cr and V mainly existed in the residual fraction. The enrichment factor and geo-accumulation index values of heavy metals were all ranked in the order of Cd > Zn > Pb > Sb > Ni > Cr > V, and these values in indoor dust were larger than those in outdoor dust. In addition, the enrichment patterns of these elements were similar in the three functional areas. The orders of non-carcinogenic risk (hazard index; HI) for the different functional areas for children were roughly the same, but there were clear differences for adults. In general, all the HIs were less than 1, which were within the internationally recognized safe range. The total carcinogenic risk (TR) was in the order of Cr > Pb > Cd for both children and adults in the three functional zones. The TRs from Cr exposure were not negligible. The TRs were significantly higher in the CmD.


Assuntos
Carcinógenos/análise , Poeira/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Material Particulado/análise , Adulto , Ar Condicionado , Criança , China , Humanos , Indústrias , Medição de Risco
18.
Bull Environ Contam Toxicol ; 102(6): 843-847, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30993357

RESUMO

A total of 28 PCB congeners were determined using gas chromatography-mass spectrometry (GC-MS) in 46 surface soils collected from the Yellow River Delta Natural Reserve (YRDNR) and its adjacent area, China. The total concentrations of PCBs in the YRDNR ranged from 0.149 to 4.32 ng/g, with a mean concentration of 0.802 ng/g. Light PCB congeners predominated in the present research area, which may be attributed to the atmospheric transportation and were also associated with the recent contamination of unintentionally produced PCBs from industrial processes. In addition, PCB 126 and PCB 169 were found to be the major toxicity contributors of dioxin-like PCBs in the YRDNR, which should require special focus.


Assuntos
Bifenilos Policlorados/análise , Rios/química , Poluentes do Solo/análise , Solo/química , China , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Bifenilos Policlorados/química , Medição de Risco , Poluentes do Solo/química
19.
Environ Pollut ; 250: 728-736, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31035155

RESUMO

Rapid development in nanotechnology and incorporation of silver nanoparticles (AgNPs) in wide range of consumer products causing the considerable release of these NPs in the environment, leading concerns for ecosystem safety and plant health. In this study, rice (Oryza sativa) was exposed to AgNPs (0, 100, 200, 500 and 1000 mg L-1) in biochar amended (2 %w/v) and un-amended systems. Exposure of plants to AgNPs alone reduced the root and shoot length, biomass production, chlorophyll contents, photosynthesis related physiological parameters as well as macro-and micronutrients in a dose dependent manner. However, in case of biochar amendment, physiological parameters i.e., net photosynthesis rate, maximum photosynthesis rate, CO2 assimilation, dark respiration and stomatal conductance reduced only 16, 6, 7, 3 and 8%, respectively under AgNPs exposure at 1000 mg L-1 dose. Meanwhile, biochar at all exposure level of AgNPs decreased the bioaccumulation of Ag in rice root and shoot tissues, thus alleviated the phyto-toxic effects of NPs on plant growth. Moreover, results showed that biochar reduced the bioavailability of AgNPs by surface complexation, suppressing dissolution and release of toxic Ag+ ions in the growth medium. The presence of biochar at least decreased 2-fold tissue contents of Ag even at highest AgNPs (1000 mg L-1) concentration. These finding suggested that biochar derived from waste biomass resources can be used effectively to prevent the bioaccumulation and subsequent trophic level transfer of emerging Ag nano-pollutant in the environment.


Assuntos
Carvão Vegetal/química , Nanopartículas Metálicas/toxicidade , Oryza/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Prata/toxicidade , Disponibilidade Biológica , Biomassa , Clorofila/metabolismo , Oryza/metabolismo , Prata/metabolismo , Solo/química
20.
J Hazard Mater ; 371: 288-294, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30856439

RESUMO

The concentrations and spatial distribution of 14 organophosphorus flame retardants (OPFRs) and plasticizers were studied in aquatic environments of China, namely, the Pearl River Delta (PRD), South China Sea (SCS) and Yellow River Estuary (YRE), as well as Tokyo Bay (TB) in Japan. These locations were characterized by different levels of socioeconomic development and human activities. The spatial pattern of OPFRs revealed their ubiquity along the coasts of China and Japan; the concentrations ranged from 15 to 1790, 1 to 147, 253 to 1720, and 107 to 284 ng L-1 in the PRD, SCS, YRE and TB, respectively. The most frequently detected OPFR was triethyl phosphate (TEP), followed by triphenylphosphine oxide (TPPO) and tris(2-chloroethyl) phosphate (TCEP). A positive relationship (R2 = 0.668, p = 0.004) was observed between OPFR contamination and socioeconomic activity, measured by gross domestic product (GDP) per capita, for the studied cities in China and Japan. The results suggest that an increase in manufacturing and construction activities in the studied areas may aggravate coastal contamination with OPFRs. The potential threat to aquatic organisms from exposure to TCEP, a suspected carcinogen, was revealed by the hazard quotient (HQ) and probabilistic assessments. Further investigation of OPFR exposure in the aquatic environment of China is urgently required.

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