49 results on '"Li-yan, Liu"'
Search Results
2. Influence on the levels of PAHs and methylated PAHs in surface soil from pollution control in China: Evidence in 2019 data compared with 2005 and 2012 data
- Author
-
Fu-Jie Zhu, Zi-Feng Zhang, Li-Yan Liu, Hong Yao, Hong-Liang Jia, Zhi Zhang, Song Cui, Bo Meng, Gang Cao, Peng-Hao Su, Xiao-Xuan Mao, Bao-Long Li, Wan-Li Ma, and Yi-Fan Li
- Subjects
Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Published
- 2023
- Full Text
- View/download PDF
3. Al2O3 coating on BaLi2Ti6O14 surface to boost its stability and rate performance
- Author
-
Ying Xie, Xiaodong Wang, Li-yan Liu, Chen-Feng Guo, Bing Zheng, Hai-Tao Yu, and Ting-Feng Yi
- Subjects
010302 applied physics ,Battery (electricity) ,Materials science ,Scanning electron microscope ,Process Chemistry and Technology ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Anode ,Coating ,Chemical engineering ,Transmission electron microscopy ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,engineering ,Particle size ,0210 nano-technology ,Layer (electronics) - Abstract
BaLi2Ti6O14, a promising anode material for lithium-ion battery application, was successfully prepared by a sol-gel method. To improve the structural stability and electrochemical performance of the materials, an ionic conductive Al2O3 layer was introduced. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the particles become smaller and distribute more uniformly because of the coating, and possible mechanism was discussed. Our experiments further showed that BLTO-4 sample has the best electrochemical performance. Furthermore, excessive coating will lead to a decrease of reversible capacity, because Al2O3 has no electrochemical activity. The charge and discharge capacities of BLTO-4 are 174.9 and 175.9 mAh g−1 after 50 cycles at 0.2 C, which are much higher than those of the pure sample (107.3 and 108.4 mAh g−1). Even at 10 C, BLTO-4 still delivers a reversible specific capacity of 98.6 mAh g−1 after 1000 cycles. The good cyclic stability and rate performance of BLTO-4 can be attributed to the reduced particle size and the advantages of the Al2O3 coating layer, which is favorable for the enhancement of the structural stability and the reduction of the charge transfer resistance of the materials.
- Published
- 2020
- Full Text
- View/download PDF
4. Seasonal variations of airborne phthalates and novel non-phthalate plasticizers in a test residence in cold regions: Effects of temperature, humidity, total suspended particulate matter, and sources
- Author
-
Chun-Yan Huo, Wen-Long Li, Li-Yan Liu, Yu Sun, Jia-Qi Guo, Liang Wang, Hayley Hung, and Yi-Fan Li
- Subjects
Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Abstract
As a class of plasticizers widely used in consumer products, some phthalate esters (PAEs) have been restricted due to their adverse health effects and ubiquitous presence, leading to the introduction of alternative non-phthalates plasticizers (NPPs) to the market. However, few studies focus on the influence of environmental parameters on the presence of these plasticizers and the potential human health risks for people living in poorly ventilated indoor spaces in cold regions. We investigated the trends of PAEs and NPPs in air in a typical indoor residence in northern China for over one year. The air concentrations of PAEs were significantly higher than those of NPPs (p0.05), indicating that PAEs are still the dominant plasticizers currently being used in the studied residence. PAEs showed seasonal fluctuation patterns of the highest levels found in summer and autumn. The temperature and relative humidity dependence for most PAEs and NPPs decreased with decreasing vapor pressure. Concentrations of the high molecular weight NPPs and PAEs positively correlated with total suspended particles (TSP). It is worth noting that the peak concentrations of PAEs and NPPs were found when the haze occurred in autumn. Principal component analysis (PCA) suggested the diverse applications of PAEs and NPPs in the indoor environment. The hazard index (HI) values observed in this study were all below international guidelines (1); however, the average carcinogenic risk (CR) values for some compounds exceeded acceptable levels (One in a million), which raised concerns about the possibility of carcinogenicity for people living indoors for long periods of time in cold regions.
- Published
- 2023
- Full Text
- View/download PDF
5. Bi modified oxidized tubular carbon nitride with high-yield singlet oxygen for propylparaben degradation: Implication for a novel oxygen activation mechanism
- Author
-
Yu-Wei Li, Shu-Zhi Li, Li-Yan Liu, Zi-Feng Zhang, and Wan-Li Ma
- Subjects
Process Chemistry and Technology ,Catalysis ,General Environmental Science - Published
- 2023
- Full Text
- View/download PDF
6. National-scale monitoring of historic used organochlorine pesticides (OCPs) and current used pesticides (CUPs) in Chinese surface soil: Old topic and new story
- Author
-
Liang Wang, Zi-Feng Zhang, Li-Yan Liu, Fu-Jie Zhu, and Wan-Li Ma
- Subjects
Soil ,China ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Hydrocarbons, Chlorinated ,Soil Pollutants ,Environmental Chemistry ,Pesticides ,Pollution ,Waste Management and Disposal ,Environmental Monitoring - Abstract
Along with the restriction and prohibition of historic used organochlorine pesticides (OCPs), current used pesticides (CUPs) were widely used as alternatives. In order to investigate the pollution characteristics of pesticides, the levels and spatial distributions of OCPs and CUPs in 154 surface soil across China were comprehensively compared. Totally, 107 target pesticides were screened, and 20 OCPs and 34 CUPs were detected. The numbers of co-occurred pesticides in single soil sample were from 17 to 36 indicating the diversity and complexity of pesticides pollution. The concentrations of OCPs in urban soils were higher than rural soils, while rural urban for CUPs. Furthermore, obviously different spatial distribution patterns were found for OCPs and CUPs. For OCPs, the secondary distribution pattern was dominant. For CUPs, the primary distribution pattern was obviously observed due to their current extensive usage. In addition, higher concentrations of both CUPs and OCPs were accumulated in the Northeast China Plain due to long-range atmospheric transport and deposition. Along with the old topic of OCPs, the study pointed out the preliminary understanding of CUPs pollution characteristic in surface soil of China, which provided a new story with the deep understanding of their environmental fate in both China and the world.
- Published
- 2023
- Full Text
- View/download PDF
7. Solar-Induced Efficient Propylparaben Photodegradation by Nitrogen Vacancy Engineered Reticulate G-C3n4: Morphology, Activity and Mechanism
- Author
-
Yu-Wei Li, Zi-Feng Zhang, Shu-Zhi Li, Li-Yan Liu, and Wan-Li Ma
- Subjects
Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Published
- 2022
- Full Text
- View/download PDF
8. Accumulations and equilibrium conditions of organophosphate esters (OPEs) in the indoor window film and the estimation of concentrations in air
- Author
-
Chun-Yan Huo, Li-Yan Liu, Hayley Hung, Yu Sun, Jia-Qi Guo, Yong-Kai Wu, Ed Sverko, and Wen-Long Li
- Subjects
Environmental Engineering ,Phosphines ,Humans ,Environmental Chemistry ,Environmental Pollutants ,Esters ,Pollution ,Waste Management and Disposal ,Organophosphates ,Environmental Monitoring ,Flame Retardants ,Phosphates - Abstract
The study of the fate of organophosphate esters (OPEs) in the interior environment is vital because of the growing use of OPEs. Organic films on glass are both sink and sources of indoor pollutants. Indoor window films have been employed as passive air samplers to collect OPEs in the indoor air. Nevertheless, little is known about the development and equilibrium condition of OPEs on indoor window films during the film formation process. In this study, the concentrations of twelve OPEs in indoor window films from different buildings on a university campus and the growth thickness of the films as a function of sampling time were investigated in different seasons. Ten out of the 12 OPEs were detected in window film with50 % frequency. Tris (2-chloroethyl) phosphate (TCEP) and tris (1-chloro-2-propyl) phosphate (TCPP), which are chlorinated and toxic OPEs, were the dominant OPEs found in the winter. The majority of OPEs in window films exhibited linear growth patterns within 77 days. Temperature, humidity, ventilation, and seasonality all affected the concentrations of various OPEs in the window films. Low molecular weight OPEs, such as tri-n-butyl phosphate and TCEP, attained equilibrium between indoor air and window films within 49 or 77 days. The indoor air concentrations of OPEs were estimated from their film concentrations based on the theoretical approach for the passive air sampler. In winter, the predicted gas-phase air concentrations of OPEs (3.7 ng/m
- Published
- 2022
- Full Text
- View/download PDF
9. Phthalates in infant cotton clothing: Occurrence and implications for human exposure
- Author
-
Wei-Wei Song, Zhi Zhang, Li-Yan Liu, Wan-Li Ma, Ed Sverko, Yu Sun, Yi-Fan Li, Zi-Feng Zhang, and Hai-Ling Li
- Subjects
China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Dibutyl phthalate ,Phthalic Acids ,Infant health ,010501 environmental sciences ,Risk Assessment ,01 natural sciences ,Clothing ,Toxicology ,chemistry.chemical_compound ,parasitic diseases ,Humans ,Environmental Chemistry ,Medicine ,Cotton Fiber ,Waste Management and Disposal ,0105 earth and related environmental sciences ,business.industry ,Infant, Newborn ,Phthalate ,Infant ,Infant exposure ,Environmental Exposure ,Infant clothing ,Pollution ,chemistry ,Human exposure ,Environmental Pollutants ,Detection rate ,business ,Environmental Monitoring - Abstract
Clothing easily adsorbed the chemicals in the environment, and became a source of human exposure to chemicals. However, large contacted surface area and long exposure duration have elevated human exposure to chemicals from clothing, such as phthalates. Among them, cotton clothing, which infants prefer to wear, has been proven to adsorb phthalates more easily than other fabrics. While infants are developing, they are easily affected by phthalates. In this study, in order to study accumulation of phthalates in infant cotton clothing during the whole process from production to the first wearing, 24 infant cotton clothing samples were collected from shopping malls in Harbin, China. High detection rates and concentrations suggest that phthalates in the environment are widely adsorbed to infant cotton clothing, and traditional laundering for infant clothing cannot remove phthalates completely. The median concentration of the total phthalates was 4.15 μg/g. Di-(2-ethylhexyl) phthalate (DEHP) has become the dominant phthalate. For the estimated daily intakes (EDIs) for infants, dibutyl phthalate (DBP) had the highest contribution, followed by di-iso-butyl phthalate (DiBP) and DEHP. Dermal absorption has become the main route of infant exposure to phthalates, and ingestion contributed very little. The result of comparing with the EDIs via dermal absorption from house air and dust suggests that clothing plays an important role of dermal absorption exposure to phthalates. For risk assessment, the carcinogenic risk of BBP and DEHP indicates that the level of DEHP in infant cotton clothing might pose potential adverse effects to infant health.
- Published
- 2019
- Full Text
- View/download PDF
10. Measurement and modeling the gas/particle partitioning of organochlorine pesticides (OCPs) in atmosphere at low temperatures
- Author
-
Wan-Li Ma, Li-Yan Liu, Li-Na Qiao, Ning-Zheng Zhu, Wei-Wei Song, Yi-Fan Li, and Zi-Feng Zhang
- Subjects
Environmental Engineering ,010504 meteorology & atmospheric sciences ,Condensation ,Sampling (statistics) ,010501 environmental sciences ,Atmospheric temperature range ,Particulates ,01 natural sciences ,Pollution ,Partition coefficient ,Atmosphere ,Environmental chemistry ,Environmental Chemistry ,Environmental science ,Particle ,Partition (number theory) ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
The gas/particle (G/P) partition of organochlorine pesticides (OCPs) has been widely investigated and well documented, but rare at low temperature. In this study, seventy-four pairs of air samples in two sampling sites in northeastern China at a wide ambient temperature range of ~63 °C (−40 to +23 °C) were simultaneously collected in both gaseous and particulate phases and eighteen OCPs in these samples were measured and analyzed, among which, partition quotient (KP) values for fifteen OCPs were determined. Seven models including those have never been used for OCPs were applied to predict the values of KP, and the results were compared with the monitoring data for the fifteen OCPs. It was found out that, L-M-Y model provided advantages over the other models, with the best agreement to the monitoring data for analyzed OCPs (90.1 ± 11.1% data points within ±1 log unit, RMSE: 0.53 ± 0.18). The predicted maximum partition (MP) domain for eleven OCPs was observed with high values of their logarithm of octanol-air partition coefficient (log KOA > 12.5), where the log KP values become a constant (−1.53), indicating that the G/P partition of OCPs is in steady state but not the equilibrium. The Li-Ma-Yang (L-M-Y model) model, considering the wet and dry depositions of particles, elucidates the necessity of non-equilibrium term for the OCPs at low temperature. These results indicate that the L-M-Y model is valid for OCPs, which renders it highly promising for describing the partition behaviors in atmosphere for SVOCs, particularly at low temperature. An equation to calculate the condensation temperature TC was also derived, which gave a new understanding on the situation of chemicals with equal distribution between gaseous and particulate phases of OCPs and other similar SVOCs, especially in Polar Regions.
- Published
- 2019
- Full Text
- View/download PDF
11. Organophosphate flame retardants in college dormitory dust of northern Chinese cities: Occurrence, human exposure and risk assessment
- Author
-
Wei-Wei Song, Hai-Ling Li, Ed Sverko, Yi-Fan Li, Wan-Li Ma, Yu Sun, Zi-Feng Zhang, Chun-Yan Huo, and Li-Yan Liu
- Subjects
Male ,China ,Environmental Engineering ,Universities ,010504 meteorology & atmospheric sciences ,010501 environmental sciences ,Risk Assessment ,01 natural sciences ,chemistry.chemical_compound ,Humans ,Environmental Chemistry ,Risk threshold ,Cities ,Health risk ,Waste Management and Disposal ,Female students ,Flame Retardants ,0105 earth and related environmental sciences ,Air Pollutants ,Organophosphate ,Dust ,Environmental Exposure ,Pollution ,Organophosphates ,chemistry ,Human exposure ,Air Pollution, Indoor ,Environmental chemistry ,Housing ,Environmental science ,Female ,Risk assessment ,Environmental Monitoring - Abstract
Organophosphate flame retardants (OPFRs) are widely added to consumer products and building materials, which may pose potential health risk to humans. But information on their contamination and human exposure in the indoor environment especially dormitories in northern China is rare. In this study, twelve OPFRs were investigated in college dormitory dust that collected from Harbin, Shenyang, and Baoding, in northern China. Indoor dust samples were also collected from homes and public microenvironments (PMEs) in Harbin for comparison. The median ∑OPFR concentrations in dormitory dust in Shenyang samples (8690 ng/g) were higher than those in Baoding (6540 ng/g) and Harbin (6190 ng/g). The median ∑OPFR concentrations in home dust (7150 ng/g) were higher than in dormitory and PME dust (5340 ng/g) in Harbin. Tris(2‑chloroethyl) phosphate (TCEP) and tris (2-chloroisopropyl) phosphate (TCIPP) were the most abundant chlorinated OPFRs, while triphenyl phosphate (TPHP) and tris(2‑butoxyethyl) phosphate (TBOEP) were the dominant non-chlorinated OPFRs. The daily intakes of ∑OPFR were estimated, with the median values for female students (2.45 ng/kg-day) higher than those for male students (2.15 ng/kg-day) while were similar to adults (2.45 ng/kg-day) in homes. The estimated daily intakes (EDI) of these OPFRs from indoor dust in Harbin were all below the recommended values. The calculated non-carcinogenic hazard quotients (10−8–10−3) from OPFRs were much lower than the theoretical risk threshold. Meanwhile, carcinogenic risk (CR) of tri‑n‑butyl phosphate (TNBP), TCEP, tris(2‑ethylhexyl) phosphate (TEHP), and tris(1,3‑dichloroisopropyl) phosphate (TDCIPP) were also estimated. The highest carcinogenic risk of TCEP for gender-specific and age-specific category range from 1.75 × 10−7 to 2.46 × 10−7 from exposure to indoor dust indicated a low potential carcinogenic risk for human exposure.
- Published
- 2019
- Full Text
- View/download PDF
12. Respiratory exposure to graphene oxide induces pulmonary fibrosis and organ damages in rats involving caspase-1/p38MAPK/TGF-β1 signaling pathways
- Author
-
Ze, Kan, Ke-Xin, Zhao, Chao, Jiang, Da-Yang, Liu, Ying, Guo, Li-Yan, Liu, Wen-Juan, Wang, Zhi-Qiang, He, Zi-Feng, Zhang, and Su-Yi, Wang
- Subjects
Environmental Engineering ,Pulmonary Fibrosis ,Health, Toxicology and Mutagenesis ,Caspase 1 ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,p38 Mitogen-Activated Protein Kinases ,Pollution ,Rats ,Transforming Growth Factor beta1 ,Animals ,Environmental Chemistry ,Graphite ,Lung ,Signal Transduction - Abstract
Numerous studies have shown that graphene oxide (GO) respiratory exposure led to severe lung injury, but whether pulmonary fibrosis caused by GO respiratory exposure is related to the activation of the caspase-1/p38MAPK/TGF-β1 remains unclear. In this study, rats were administrated GO by intratracheal instillation and fed for three months, and the molecular mechanisms of GO on the pulmonary fibrosis and other organ damage caused by GO respiratory exposure were examined. The results showed that the expression of caspase-1/p38MAPK/TGF-β1 pathway-related factors were significantly elevated with the increase of exposure concentrations of GO. Those data proved that the caspase-1/p38MAPK/TGF-β1 signaling pathway was involved in the pulmonary fibrosis caused by GO respiratory exposure. The trends of related factors also proved that the caspase-1/p38MAPK/TGF-β1 pathway was likely to play a dominant role in the sub-acute and sub-chronic stages. The other organ damage examination found that the liver and spleen were damaged initially by the GO respiratory exposure. Meanwhile for the testicle, although the acute injury was severe, signs of recovery were found during the three-month trial period.
- Published
- 2022
- Full Text
- View/download PDF
13. Optimization and performance evaluation of double-stranded probe in real-time PCR
- Author
-
Yong-jun Han, Li-yan Liu, Qi-qi Liu, and Sheng-qi Wang
- Subjects
SARS-CoV-2 ,Oligonucleotides ,Biophysics ,COVID-19 ,Humans ,RNA, Viral ,Cell Biology ,Real-Time Polymerase Chain Reaction ,Sensitivity and Specificity ,Molecular Biology ,Biochemistry - Abstract
TaqMan probe-based real-time PCR (qPCR/RT-qPCR) has been widely used in various fields because of its high sensitivity and specificity. However, TaqMan probes are associated with a relatively higher background signal, and hence negatively affect the detection results.Double-stranded probes (DSPs) were designed for the high sensitive detection of hepatitis B virus (HBV) DNA and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using qPCR/RT-qPCR. Old DSPs (ODSPs) consist of different lengths of positive and negative strands with complementary oligonucleotides. We systematically optimized ODSPs length, the free energy of hybridization (ΔG) between complementary oligonucleotides, and the length of sticky ends, and the novel DSPs performances were evaluated in comparison with other types of probes.By using similar length positive and negative strands, controlling ΔG between complementary oligonucleotides to approximately -30 kcal/mol, and maintaining the sticky end length at 4-6 nt, the analytical performances of DSPs were significantly improved. Compared with other types of probes, DSPs are advantageous in fluorescence signal intensity and sensitivity.DSPs can further improve the detection sensitivity and the detection rate of low-concentration samples in molecular diagnosis.
- Published
- 2022
- Full Text
- View/download PDF
14. Non-equilibrium influence on G/P partitioning of PAHs: Evidence from the diurnal and nocturnal variation
- Author
-
Fu-Jie Zhu, Sun-Zu-Li Arina, Zi-Feng Zhang, Li-Yan Liu, Wei-Wei Song, Yuan Cheng, Jiu-Meng Liu, and Wan-Li Ma
- Subjects
Air Pollutants ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Temperature ,Public Health, Environmental and Occupational Health ,Environmental Chemistry ,Particulate Matter ,Seasons ,General Medicine ,General Chemistry ,Polycyclic Aromatic Hydrocarbons ,Pollution ,Environmental Monitoring - Abstract
Gas/particle (G/P) partitioning is an important behavior for the atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). In this study, paired daytime and nighttime air samples were collected for one year in order to study the diurnal and nocturnal variations of concentration and G/P partitioning of PAHs. Higher PAHs concentrations in total phase were observed in nighttime. The geomean (GM) concentrations of Σ
- Published
- 2022
- Full Text
- View/download PDF
15. Particle/gas partitioning behavior of polychlorinated biphenyls (PCBs) in global atmosphere: Equilibrium or steady state?
- Author
-
Li-Na Qiao, Wan-Li Ma, Li-Yan Liu, Zi-Feng Zhang, Wei-Wei Song, Hong-Liang Jia, Anatoly N. Nikolaev, Robie W. Macdonald, and Yi-Fan Li
- Subjects
Atmospheric Science ,General Environmental Science - Published
- 2022
- Full Text
- View/download PDF
16. PAHs in Chinese atmosphere Part I: Concentration, source and temperature dependence
- Author
-
Yi-Fan Li, Wan-Li Ma, Hongliang Jia, Li-Yan Liu, and Meng Yang
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Coal combustion products ,010501 environmental sciences ,Seasonality ,medicine.disease ,Atmospheric sciences ,01 natural sciences ,Atmosphere ,Environmental chemistry ,medicine ,Environmental science ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
The study on atmospheric polycyclic aromatic hydrocarbons (PAHs) in China has regional and global significance to understand the large scale atmospheric transport of PAHs. In this study, 16 US EPA priority PAHs were analyzed in more than 500 pairs of gas and particle phases samples, which were collected on the same schedule on a weekly basis from August 2008 to July 2009 at 11 urban sites (6 northern cities and 5 southern cities) across China. The average concentration was 239 ± 329 ng/m3 and 165 ± 164 ng/m3 for the northern cities and the southern cities, respectively. Different seasonal variations of atmospheric PAHs were observed between northern cities and southern cities, which were mainly caused by the different temperature effects in winter. Identified by principal component analysis, coal combustion and vehicle exhaust were the major sources of atmospheric PAHs in northern and southern cities of China, respectively. The temperature dependences of atmospheric PAHs were also different, which were caused by the different influences of temperature on identified sources. To our knowledge, this is the first comprehensive study to report the difference with concentrations, seasonal variations, sources and temperature dependences of atmospheric PAHs between northern cities and southern cities in China.
- Published
- 2018
- Full Text
- View/download PDF
17. Temporal trends of atmospheric PAHs: Implications for the gas-particle partition
- Author
-
Wei-Wei Song, Hui-Ze Fan, Li-Yan Liu, Fu-Jie Zhu, Li-Na Qiao, Wen-Long Li, Peng-Tuan Hu, Wan-Li Ma, and Zi-Feng Zhang
- Subjects
Atmosphere ,Atmospheric Science ,Deposition (aerosol physics) ,Monitoring data ,Environmental science ,Particle ,Partition (number theory) ,Particulates ,Phase fraction ,Atmospheric sciences ,General Environmental Science - Abstract
Gas-particle (G/P) partition is the determining factor to the behaviors of semi-volatile organic compounds (SVOCs) in atmosphere, such as transport and deposition. Based on a case study on the measurement of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Harbin City in China from June 2014 to May 2019, the long-term temporal trend of G/P partition of PAHs and its influencing factors were comprehensively studied. The results indicated that an obvious decreasing temporal trend was observed for total suspended particle (TSP) with the annual mean concentrations of 180, 173, 134, 132, and 119 μg/m3 for the five years. The results demonstrated the effectiveness of the Clean Air Action on decreasing TSP levels in Harbin City. For most PAHs, obvious long-term temporal trends and seasonal variations were observed for the particulate phase fraction (φP) and the G/P partitioning quotient (KP) by fitting with a simple harmonic regression method. Significant correlations between φP with temperature and TSP indicated their influences on the temporal trend of φP. Similarly, the temperature was also the direct influencing factor to the temporal trend of KP. For the five years, non-obvious differences were observed with the linear relationships between log KP vs. log KOA, and between log KP vs. log PL. The comparison between the monitoring data of φP and log KP with the prediction data from the G/P partitioning models indicated that the predictions of the models did not well match all the monitoring data for the period. Therefore, more studies should be conducted to better understand the G/P partitioning mechanism of PAHs in atmosphere and to establish more accurate G/P partitioning models. In summary, the results of the present study provided new insight into the G/P partitioning behavior of PAHs in the atmosphere, especially for the temporal trend of φP and log KP.
- Published
- 2021
- Full Text
- View/download PDF
18. Occurrence and source apportionment of atmospheric halogenated flame retardants in Lhasa City in the Tibetan Plateau, China
- Author
-
Wei-Wei Song, Wan-Li Ma, Yi-Xing Yuan, Yi-Fan Li, Li-Yan Liu, Wen-Long Li, Zi-Feng Zhang, and Chun-Yan Huo
- Subjects
geography ,Environmental Engineering ,Plateau ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Contribution function ,010501 environmental sciences ,Dechlorane plus ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,Polybrominated diphenyl ethers ,chemistry ,Environmental chemistry ,Environmental behavior ,Correlation analysis ,Environmental Chemistry ,Environmental science ,Potential source ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Active air samples were collected in Lhasa, one of the highest cities in the world (3650m above sea level) located in the Tibetan Plateau, and were analyzed for 38 halogenated flame retardants (HFRs), including polybrominated diphenyl ethers (PBDEs), non-PBDE brominated flame retardants (NBFRs) and dechlorane plus (DPs). The median concentrations of PBDEs, NBFRs and DPs were 40, 23 and 0.21pg/m3, respectively. Correlation analysis indicated the common source and/or similar environmental behavior for several HFRs. The Clausius-Clapeyron equation was applied to diagnose the sources of lower molecular weight HFRs (LMW-HFRs), which suggested that the gaseous LMW-HFRs at Lhasa were more controlled by regional or long-range atmospheric transport rather than the temperature-driven evaporation from local contaminated surfaces. Finally, the potential source contribution function model was applied to assess the influences of air parcels on the atmospheric concentrations of HFRs in Lhasa, which suggested that the sources of higher molecular weight HFRs (HMW-HFRs) were mostly originated from local emissions, while the others were originated from long-range atmospheric transport.
- Published
- 2017
- Full Text
- View/download PDF
19. Occurrence and fate of benzotriazoles UV filters in a typical residential wastewater treatment plant in Harbin, China
- Author
-
Li-Yan Liu, Fu-Jie Zhu, Xue Zhao, Wei-Wei Song, Zi-Feng Zhang, Wan-Li Ma, Yi-Fan Li, and Lei Xu
- Subjects
Pollution ,China ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Wastewater ,010501 environmental sciences ,Toxicology ,Waste Disposal, Fluid ,01 natural sciences ,Rivers ,Effluent ,0105 earth and related environmental sciences ,media_common ,Pollutant ,Sewage ,010401 analytical chemistry ,General Medicine ,Triazoles ,0104 chemical sciences ,Environmental chemistry ,Environmental science ,Water treatment ,Sewage treatment ,Seasons ,Aeration ,Surface water ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Benzotriazoles (BTs) UV filters are widely used as ultraviolet absorbents for our daily products, which received increasing attention in the past decades. Residential wastewater treatment plant (WWTP) is both an important sink for wastewater and a key pollution source for receiving water for these chemicals. In this study, pretreatment and gas chromatography-tandem mass spectrometry analysis method were developed to determine the occurrence and fate of 9 BTs UV filters in wastewater and sludge from the WWTP with anaerobic-oxic treatment process (A/O) and biological aerated filter treatment process (BAF). Totally, 81 wastewater samples and 11 sludge samples were collected in four seasons. In wastewater, UV-326 and UV-329 were frequently detected, while the highest mean concentrations were detected for UV-234 and UV-329. The concentrations were in the range ofLOQs up to several hundred nanograms per liter. The removal efficiency of BTs UV filters was85% in A/O process and 60-77% in BAF process except for UV-350, which was more difficult to remove with lower removal efficiencies of 33.3% for both A/O and BAF. All the target chemicals except for UV-320 were detected in sludge samples with the mean concentration ranging from 0.90 ng/g to 303.39 ng/g. There was no significant difference with concentrations and removal efficiency among different seasons. Higher detection frequency and concentration of BTs UV filters in downstream of the receiving water system indicated the contribution of effluent of the WWTP. Compared with other rivers, the lower concentrations in surface water in the Songhua River indicated light pollution status with of BTs UV filters.
- Published
- 2017
- Full Text
- View/download PDF
20. Occurrence, sources and human exposure assessment of SCCPs in indoor dust of northeast China
- Author
-
Hing Man Chan, Li-Yan Liu, Chong-Jing Gao, Wan-Li Ma, Chun-Yan Huo, Hai-Ling Li, Li-Hua Liu, Wen-Long Li, and Yi-Fan Li
- Subjects
China ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Factor score ,010501 environmental sciences ,Toxicology ,Risk Assessment ,01 natural sciences ,Human health ,Chlorinated paraffins ,Environmental risk ,Hydrocarbons, Chlorinated ,Humans ,Daily exposure ,0105 earth and related environmental sciences ,Inhalation Exposure ,Significant difference ,Infant ,Dust ,General Medicine ,Pollution ,Carbon ,Paraffin ,Human exposure ,Air Pollution, Indoor ,Child, Preschool ,Environmental chemistry ,Environmental science ,Environmental Monitoring - Abstract
Short-chain chlorinated paraffins (SCCPs) are widely used chemicals in household products and might cause adverse human health effects. However, limited information is available on the occurrence of SCCPs in indoor environments and their exposure risks on humans. In this study the concentrations, profiles and human exposure of SCCPs in indoor dust from five different indoor environments, including commercial stores, residential apartments, dormitories, offices and laboratories were characterized. The SCCPs levels ranged from 10.1 to 173.0 μg/g, with the median and mean concentration of 47.2 and 53.6 μg/g, respectively. No significant difference was found on concentrations among the five microenvironments. The most abundant compounds in indoor dust samples were homologues of C 13 group, Cl 7 group and N 20 (N is the total number of C and Cl) group. In the five microenvironments, commercial stores were more frequently exposed to shorter carbon chained and higher chlorinated homologues. Three potential sources for SCCPs were identified by the multiple linear regression of factor score model and correspondence analysis. The major sources of SCCPs in indoor dust were technical mixtures of CP–42 (42% chlorine, w/w) and CP–52 b (52% chlorine, w/w). The total daily exposure doses and hazard quotients (HQ) were calculated by the human exposure models, and they were all below the reference doses and threshold values, respectively. Monte Carlo simulation was applied to predict the human exposure risk of SCCPs. Infants and toddlers were at risk of SCCPs based on predicted HQ values, which were exceeded the threshold for neoplastic effects in the worst case. Our results on the occurrences, sources and human exposures of SCCPs will be useful to provide a better understanding of SCCPs behaviors in indoor environment in China, and to support environmental risk evaluation and regulation of SCCPs in the world.
- Published
- 2017
- Full Text
- View/download PDF
21. Relative developmental toxicity of short-chain chlorinated paraffins in Zebrafish (Danio rerio) embryos
- Author
-
Li-Yan Liu, Wan-Li Ma, Li-Hua Liu, Yi-Fan Li, Hing Man Chan, and Mehmet Coelhan
- Subjects
Hypothalamo-Hypophyseal System ,Thyroid Hormones ,medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Thyroid Gland ,0211 other engineering and technologies ,Danio ,Developmental toxicity ,Gene Expression ,DIO2 ,02 engineering and technology ,010501 environmental sciences ,Toxicology ,01 natural sciences ,Chlorinated paraffins ,Internal medicine ,Hydrocarbons, Chlorinated ,medicine ,Animals ,Humans ,Zebrafish ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Triiodothyronine ,biology ,Thyroid ,General Medicine ,biology.organism_classification ,Pollution ,Endocrinology ,medicine.anatomical_structure ,Paraffin ,Toxicity ,Environmental Pollutants ,Chlorine ,Environmental Monitoring ,Hormone - Abstract
Short-chain chlorinated paraffins (SCCPs) are ubiquitous in the environment and might cause adverse environmental and human health effects. Little is known about the relative toxicity of different SCCP compounds especially during development. The objective of this study was to characterize and compare effects of seven SCCP groups at environmentally relevant levels, using a zebrafish (Danio rerio) model. Observations on malformation, survival rates at 96 h post fertilization (hpf), and hatching rates at 72 hpf indicated that the C10- groups (C10H18Cl4, 1,2,5,6,9,10-C10H16Cl6 and C10H15Cl7) were more toxic than the C12- groups (C12H22Cl4, C12H19Cl7 and 1,1,1,3,10,12,12,12-C12H18Cl8) and Cereclor 63L. The C10- groups were also more potent than C12- groups and Cereclor 63L in decreasing thyroid hormone levels. Among the three compounds within the C10- group, the compounds with less chlorine content had stronger effects on sub-lethal malformations but less effects on triiodothyronine (T3) and tetraiodothyronine (T4). Only C10H18Cl4 significantly decreased the mRNA expression of tyr, ttr, dio2 and dio3 at a dose-dependent manner suggesting that the specific mode of actions differ with different congeners. The mechanisms of disruption of thyroid status by different SCCPs could be different. C10H18Cl4 might inhibit T3 production through the inhibition effect on dio2. These results indicate that SCCP exposure could alter gene expression in the hypothalamic-pituitary-thyroid (HPT) axis and thyroid hormone levels. The mechanisms of disruption of thyroid status by different SCCPs could be different. Our results on the relative developmental toxicities of SCCPs will be useful to reach a better understanding of SCCP toxicity supporting environmental risk evaluation and regulation and used as a guidance for environmental monitoring of SCCPs in the future.
- Published
- 2016
- Full Text
- View/download PDF
22. Multi-year air monitoring of legacy and current-use brominated flame retardants in an urban center in northeastern China
- Author
-
Wei-Wei Song, Zi-Feng Zhang, Wen-Long Li, Li-Na Qiao, Yi-Fan Li, Wan-Li Ma, Li-Yan Liu, and Chun-Yan Huo
- Subjects
Air Pollutants ,China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Chemistry ,010501 environmental sciences ,01 natural sciences ,Pollution ,Atmosphere ,Air monitoring ,Polybrominated diphenyl ethers ,Air pollutants ,Environmental chemistry ,Halogenated Diphenyl Ethers ,Environmental Chemistry ,Relative humidity ,Cities ,Waste Management and Disposal ,Environmental Monitoring ,Flame Retardants ,0105 earth and related environmental sciences - Abstract
The occurrence and temporal trends of polybrominated diphenyl ethers (PBDEs) and non-PBDE brominated flame retardants (NBFRs) were investigated in an urban atmosphere of Northeast China in consecutive six years (2008-2013). Among all chemicals, BDE-209, l,2,5,6,9,10-hexabromocyclododecane (HBCD), and decabromodiphenylethane (DBDPE) were the three most dominant compounds. During the period, the levels of pentabromodiphenyl ethers in the gas-phase and octabromodiphenyl ethers in the particle-phase significantly decreased, while the levels of BDE-209 and NBFRs increased in either the gas-phase or particle-phase. Ambient temperature was the most significant variable that influenced the gas-phase and particle-phase concentrations of BFRs, followed by wind speed and relative humidity. A stronger temperature dependence of the atmospheric concentrations was found for lower mass BFRs. Gas-particle partitioning studies suggested PBDEs in the urban atmosphere of Northeast China were at steady-state. Steady-state equation can also well describe the partitioning behavior for NBFRs, suggesting that the atmospheric partitioning behaviors of NBFRs were similar to those of PBDEs.
- Published
- 2016
- Full Text
- View/download PDF
23. Research on persistent organic pollutants in China on a national scale: 10 years after the enforcement of the Stockholm Convention
- Author
-
Wan-Li Ma, Yi-Fan Li, Hongliang Jia, Zi-Feng Zhang, Wei-Wei Song, and Li-Yan Liu
- Subjects
China ,Time Factors ,010504 meteorology & atmospheric sciences ,International Cooperation ,Health, Toxicology and Mutagenesis ,Developing country ,Distribution (economics) ,Environmental pollution ,010501 environmental sciences ,Toxicology ,01 natural sciences ,Environmental protection ,Political science ,Soil Pollutants ,Emission inventory ,Enforcement ,Environmental planning ,0105 earth and related environmental sciences ,Air Pollutants ,Government ,business.industry ,Research ,General Medicine ,Pollution ,Monitoring program ,Environmental Pollution ,business - Abstract
As a signatory of the Stockholm Convention and the largest developing country, China plays a very important role in implementation of the convention to reduce and finally eliminate persistent organic pollutants (POPs) in the world. In the past ten years after the enforcement in 2004, Chinese Government and scientists have made great progress on the study of POPs. The present work aims to provide an overview on recent studies on POPs in China, with particular focus on usage/emission inventory, residue inventory, and pollution status of POPs on national scale. Several legend (old) and new target POPs were comprehensively summarized with progress on inventory. Furthermore, several national scale monitoring programs have been selected for the occurrence, spatial and temporal trends of POPs in China, which are compared with Asian data and Global data. Based on the observed results, some important scientific issues, such as the primary and secondary distribution patterns, the primary and secondary fractionations, and air-soil exchange of POPs, are also discussed. It is proposed that more studies should be carried out for the new targeted POPs in future for both the national and global interests.
- Published
- 2016
- Full Text
- View/download PDF
24. Phthalates in dormitory and house dust of northern Chinese cities: Occurrence, human exposure, and risk assessment
- Author
-
Wei-Wei Song, Jia Li, Chong-Jing Gao, Mohammed O.A. Mohammed, Wan-Li Ma, Zi-Feng Zhang, Kurunthachalam Kannan, Yi-Fan Li, Li-Yan Liu, Hai-Ling Li, and Chun-Yan Huo
- Subjects
Male ,China ,endocrine system ,Environmental Engineering ,Adolescent ,Universities ,010504 meteorology & atmospheric sciences ,Dibutyl phthalate ,Phthalic Acids ,010501 environmental sciences ,Risk Assessment ,01 natural sciences ,Young Adult ,chemistry.chemical_compound ,Environmental health ,Humans ,Environmental Chemistry ,Significant risk ,Cities ,Health risk ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Phthalate ,Dust ,Environmental Exposure ,Environmental exposure ,Hazard index ,Pollution ,chemistry ,Human exposure ,Environmental science ,Female ,Risk assessment - Abstract
Phthalates are widely used chemicals in household products, which severely affect human health. However, there were limited studies emphasized on young adults' exposure to phthalates in dormitories. In this study, seven phthalates were extracted from indoor dust that collected in university dormitories in Harbin, Shenyang, and Baoding, in the north of China. Dust samples were also collected in houses in Harbin for comparison. The total concentrations of phthalates in dormitory dust in Harbin and Shenyang samples were significantly higher than those in Baoding samples. The total geometric mean concentration of phthalates in dormitory dust in Harbin was lower than in house dust. Di-(2-ethylhexyl) phthalate (DEHP) was the most abundant phthalate in both dormitory and house dust. The daily intakes of the total phthalates, carcinogenic risk (CR) of DEHP, hazard index (HI) of di-isobutyl phthalate (DiBP), dibutyl phthalate (DBP), and DEHP were estimated, the median values for all students in dormitories were lower than adults who live in the houses. Monte Carlo simulation was applied to predict the human exposure risk of phthalates. HI of DiBP, DBP, and DEHP was predicted according to the reference doses (RfD) provided by the United States Environmental Protection Agency (U.S.EPA) and the reference doses for anti-androgenicity (RfD AA) developed by Kortenkamp and Faust. The results indicated that the risks of some students had exceeded the limitation, however, the measured results were not exceeded the limitation. Risk quotients (RQ) of DEHP were predicted based on China specific No Significant Risk Level (NSRL) and Maximum Allowable Dose Level (MADL). The predicted results of CR and RQ of DEHP suggested that DEHP could pose a health risk through intake of indoor dust.
- Published
- 2016
- Full Text
- View/download PDF
25. Distribution patterns and characterization of outdoor fine and coarse particles
- Author
-
Mohammed O.A. Mohammed, Yi-Fan Li, Li yan Liu, Mei yun Qi, Mohammed A.E.M. Ibrahim, Wan-Li Ma, Feng yan Wang, Na Lv, Ahmed A. Elzaki, and Wei wei Song
- Subjects
Pollution ,Total organic carbon ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Analytical chemistry ,PM2.5 ,010501 environmental sciences ,Atmospheric sciences ,Discriminant analysis ,01 natural sciences ,Hierarchical clustering ,Severe cold ,Wind speed ,Early winter ,PM10 ,Positive matrix factorization ,Environmental science ,Receptor model ,Relative humidity ,Waste Management and Disposal ,0105 earth and related environmental sciences ,media_common - Abstract
Simultaneous measurements of fine (PM 2.5 ) and coarse (PM 10 ) particles have been performed during three sampling period: summertime, early winter before the heating period, and during the winter heating. The sampling was done at an urban site, Harbin City, China, to apportion pollution sources and to investigate the impacts of weather parameters and emission sources on distribution patterns of PM 2.5 and PM 10 and their chemical compositions. Two chemometric techniques, hierarchical clustering analysis (HCA) and discriminant analysis (DA), and a receptor model (PMF5) were applied. The average mass concentrations of fine and coarse particles during the whole study period (i.e. annual averages), were 82.4 μg/m 3 and 120.1 μg/m 3 , with relative humidity and wind speed being the main factors influencing distribution patterns of PM 2.5 and PM 10, while sum of major ions ( NO 3 − , NH 4 + , SO 4 2 − ), and organic carbon (OC) were the greater contributor to total mass concentrations. According to DA, the distribution patterns of PM 2.5 and PM 10 during the winter heating period were distinct but overlapping in summer and early winter before heating, implying that, PM 2.5 and PM 10 were originated from different sources during the winter heating period but from similar sources during the other two sampling periods. This claim was further supported by PMF results. Canonical discriminant function coefficients of DA have shown species such as OC, EC, SO 4 2 − , NO 3 − , Cl − , Ti, Sr, Ca 2+ , Ni, and Ba to be good predictors/discriminants responsible for the differences between the three sampling periods. HCA visualized the interrelations among the source markers, while the PMF5 modeling confirmed HCA findings.
- Published
- 2016
- Full Text
- View/download PDF
26. Distribution patterns, infiltration and health risk assessment of PM2.5-bound PAHs in indoor and outdoor air in cold zone
- Author
-
Na Lv, Mohammed O.A. Mohammed, Wei-Wei Song, Yongliang Ma, Mei-yun Qi, Wen-Long Li, Afed Ulla Khan, Ding-zhen Wang, Li-Yan Liu, Feng-yan Wang, Yi-Fan Li, and Wan-Li Ma
- Subjects
Chrysene ,China ,Crop residue ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Coal combustion products ,010501 environmental sciences ,Atmospheric sciences ,Risk Assessment ,01 natural sciences ,chemistry.chemical_compound ,Humans ,Environmental Chemistry ,Relative humidity ,Cities ,Particle Size ,Polycyclic Aromatic Hydrocarbons ,0105 earth and related environmental sciences ,Air Pollutants ,Retene ,Health risk assessment ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Particulates ,Infiltration (HVAC) ,Pollution ,Cold Temperature ,chemistry ,Air Pollution, Indoor ,Environmental science ,Particulate Matter ,Environmental Monitoring - Abstract
In this study we investigated the distribution patterns, infiltration and health risk assessment of PM2.5-bound PAHs in indoor and outdoor air done in Harbin city, northeastern China. Simultaneous indoor and outdoor sampling was done to collect 264 PM2.5 samples from four sites during winter, summer, and spring. Infiltration of PAHs into indoors was estimated using Retene, Benzo [ghi]perylene and Chrysene as reference compounds, where the latter compound was suggested to be a good estimator and subsequently used for further calculation of infiltration factors (IFs). Modeling with positive matrix factorization (PMF5) and estimation of diagnostic isomeric ratios were applied for identifying sources, where coal combustion, crop residues burning and traffic being the major contributors, particularly during winter. Linear discriminant analysis (LDA) has been utilized to show the distribution patterns of individual PAH congeners. LDA showed that, the greatest seasonal variability was attributed to high molecular weight compounds (HMW PAHs). Potential health risk of PAHs exposure was assessed through relative potency factor approach (RPF). The levels of the sum of 16 US EPA priority PAHs during colder months were very high, with average values of 377 ± 228 ng m(-)(3) and 102 ± 75.8 ng m(-)(3), for the outdoors and indoors, respectively. The outdoor levels reported to be 19 times higher than the outdoor concentrations during warmer months (summer + spring), while the indoor concentrations were suggested to be 9 times and 10 times higher than that for indoor summer (average 11.73 ± 4 ng m(-3)) and indoor spring (9.5 ± 3.3 ng m(-3)). During nighttime, outdoor PAHs revealed wider range of values compared to datytime which was likely due to outdoor temperature, a weather parameter with the strongest negative influence on ∑16PAHs compared to low impact of relative humidity and wind speed.
- Published
- 2016
- Full Text
- View/download PDF
27. Use Videostrobokymography to Quantitatively Analyze the Vibratory Characteristics Before and After Conservative Medical Treatment of Vocal Fold Leukoplakia
- Author
-
Xiaowei Gao, Yongwang Huang, Jie Ouyang, and Li-Yan Liu
- Subjects
Adult ,Male ,VOICE HOARSENESS ,medicine.medical_specialty ,Time Factors ,Voice Quality ,Video Recording ,Urology ,Vocal Cords ,Vibration ,Laryngeal Diseases ,03 medical and health sciences ,Speech and Hearing ,0302 clinical medicine ,Phonation ,Predictive Value of Tests ,otorhinolaryngologic diseases ,Humans ,Medicine ,In patient ,Prospective Studies ,Stroboscopy ,030223 otorhinolaryngology ,Prospective cohort study ,Leukoplakia ,Voice Disorders ,Medical treatment ,business.industry ,Kymography ,Recovery of Function ,Middle Aged ,LPN and LVN ,medicine.disease ,Biomechanical Phenomena ,Surgery ,Conservative treatment ,Treatment Outcome ,medicine.anatomical_structure ,Otorhinolaryngology ,Case-Control Studies ,030220 oncology & carcinogenesis ,Vocal folds ,Female ,business ,Open quotient - Abstract
To quantitatively analyze the vibratory characteristics of vocal folds before and after conservative treatments to evaluate the outcomes of conservative treatments for vocal fold leukoplakia using videostrobokymography (VSK).This is a prospective study.Twenty patients and 20 controls were enrolled into the study. All patients received conservative treatments for 3 weeks and received VSK examination before and 3 weeks after the treatments. All controls only received VSK examination once. Vocal fold lengths of 25%, 50%, and 75% were chosen as the line-scan positions to evaluate the vocal fold vibration. Open quotient (OQ) and asymmetry index (AI) were obtained using VSK.Significant improvements in the main symptoms including voice hoarseness were found. Videostroboscopic findings showed that the white lesions on the vocal folds almost completely disappeared in all patients, and the vocal fold flexibility returned to normal. All OQs and AIs at each line-scan position in patients before the treatments were larger than those in controls (P 0.017), whereas all OQs and AIs at each line-scan position decreased 3 weeks after conservative treatments (P 0.017). No significant differences in OQs and AIs at each line-scan position were detected between patients after the treatments and controls (P0.017).VSK could quantitatively evaluate the vibratory characteristics of vocal folds before and after the treatments, and conservative treatment could improve VSK measurements to normal control values, suggesting that VSK is a tool to assess the outcomes of the conservative treatments for vocal fold leukoplakia.
- Published
- 2016
- Full Text
- View/download PDF
28. Phthalate metabolites in urine of Chinese young adults: Concentration, profile, exposure and cumulative risk assessment
- Author
-
Nanqi Ren, Li-Yan Liu, Wan-Li Ma, Chong-Jing Gao, Ning-Zheng Zhu, Ying Guo, Ling Jiang, Kurunthachalam Kannan, and Yi-Fan Li
- Subjects
Adult ,0301 basic medicine ,China ,Environmental Engineering ,Urinary system ,Phthalic Acids ,Urine ,010501 environmental sciences ,Risk Assessment ,01 natural sciences ,Toxicology ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,Humans ,Environmental Chemistry ,Food science ,Young adult ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Phthalate ,Environmental Exposure ,Environmental exposure ,Pollution ,Hazard quotient ,030104 developmental biology ,chemistry ,Human exposure ,Environmental Pollutants ,Cumulative risk assessment - Abstract
Phthalates are widely used in consumer products. People are frequently exposed to phthalates due to their applications in daily life. In this study, 14 phthalate metabolites were analyzed in 108 urine samples collected from Chinese young adults using high-performance liquid chromatography-tandem mass spectrometry. The total concentrations of 14 phthalate metabolites ranged from 71.3 to 2670 ng/mL, with the geometric mean concentration of 306 ng/mL. mBP and miBP were the two most abundant compounds, accounting for 48% of the total concentrations. Principal component analysis suggested two major sources of phthalates: one dominated by the DEHP metabolites and one by the group of mCPP, mBP and miBP metabolites. The estimated daily intakes of DMP, DEP, DBP, DiBP and DEHP were 1.68, 2.14, 4.12, 3.52 and 1.26-2.98 μg/kg-bw/day, respectively. In a sensitivity analysis, urinary concentration and body weight were the most influential variables for human exposure estimation. Furthermore, cumulative risk for hazard quotient (HQ) and hazard index (HI) were evaluated. Nearly half of Chinese young adults had high HI values exceeding the safe threshold. This is the first study on the occurrence and human exposure to urinary phthalate metabolites with Chinese young adults.
- Published
- 2016
- Full Text
- View/download PDF
29. Substituted diphenylamine antioxidants (SDPAs) in typical domestic wastewater treatment plants and Songhua River in the northeast of China
- Author
-
Wan-Li Ma, Bo Meng, Li-Yan Liu, Xue Zhang, Yi-Fan Li, Ming-yu Sun, Wen-Long Li, Wei-Wei Song, and Zi-Feng Zhang
- Subjects
China ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,0208 environmental biotechnology ,Occurrence data ,02 engineering and technology ,Wastewater ,010501 environmental sciences ,01 natural sciences ,Antioxidants ,Water Purification ,chemistry.chemical_compound ,Rivers ,medicine ,Environmental Chemistry ,Effluent ,0105 earth and related environmental sciences ,Diphenylamine ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Seasonality ,medicine.disease ,Pollution ,020801 environmental engineering ,chemistry ,Environmental chemistry ,Environmental science ,Sewage treatment ,Seasons ,Surface water ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Limited studies focus on the occurrence, removal rate and seasonal variation of substituted diphenylamine antioxidants (SDPAs) in surface water and wastewater in China. In this paper, the detection method of SDPAs was established by the ultra-performance liquid chromatography-tandem mass spectrometry. Daily variations suggested that significant variations were found for the concentrations of some SDPAs in the influent. It was found that the SDPAs could be detected in all the effluent samples and C8/C8-DPA was the predominant compound in two WWTPs. The levels of most SDPAs in the effluent were much lower than that of influent, with the removal efficiencies of total SDPAs ranged from 57.9% to 84.2%. There were significant differences with the SDPA concentrations in the influent between different seasons. Higher concentrations of SDPAs were found at downstream than those of upstream. The results of this study provide more environmental occurrence data and new insights into the research on the environmental fate of these compounds.
- Published
- 2020
- Full Text
- View/download PDF
30. Seasonal variation and influence factors of organophosphate esters in air particulate matter of a northeastern Chinese test home
- Author
-
Chun-Yan Huo, Yu Sun, Li-Yan Liu, Wan-Li Ma, Wei-Wei Song, Jia-Qi Guo, Li Wang, Ed Sverko, Zhi Zhang, Yi-Fan Li, Zi-Feng Zhang, Hai-Ling Li, and Chongguo Tian
- Subjects
China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Organophosphate ,Suspended particles ,Esters ,010501 environmental sciences ,Particulates ,Seasonality ,medicine.disease ,01 natural sciences ,Pollution ,Organophosphates ,chemistry.chemical_compound ,chemistry ,Environmental chemistry ,medicine ,Environmental Chemistry ,Environmental science ,Particulate Matter ,Seasons ,Waste Management and Disposal ,Environmental Monitoring ,Flame Retardants ,0105 earth and related environmental sciences - Abstract
To investigate the seasonal variation of organophosphate esters (OPEs) in air particulate matter (PM) and the corresponding influence factors in indoor environment, 104 indoor PM samples were collected in a test home, Harbin, China, from March 2017 to March 2018. The Σ12OPEs concentrations ranged from 0.41 ng/m3 to 940 ng/m3. Tris(1-chloro-2-propyl) phosphate (TCIPP) was the most abundant OPE and accounted for 83.2% of the total OPEs. The Σ12OPEs concentrations in spring and summer were higher than those in autumn and winter. Outdoor total suspended particles (TSP) were the main factor that affected the concentration variation of OPEs in PM samples in the test home. Comparisons of the gas/particle (G/P) partitioning equilibrium models indicated that the Dachs-Eisenreich (D-E) model estimates were more reliable than the other models in this study. The particle fractions of OPEs with log KOA > 10.51 that predicted by all four models generally well matched the measured OPE particle fractions in the literatures. To OPEs with lower molecular weight, inhalation was the main exposure route and ingestion contributed mostly to OPEs with higher molecular weight. In addition, the estimated daily intakes (EDIs) and carcinogenic risks (CRs) posed by OPEs were all below the recommended values, indicating that the current OPE levels in the test home were within the safe thresholds.
- Published
- 2020
- Full Text
- View/download PDF
31. Five-year trends of selected halogenated flame retardants in the atmosphere of Northeast China
- Author
-
Li-Na Qiao, Yi-Fan Li, Wen-Long Li, Wan-Li Ma, Zi-Feng Zhang, Wei-Wei Song, and Li-Yan Liu
- Subjects
China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Air pollution ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,Gas phase ,Atmosphere ,Polybrominated diphenyl ethers ,Air pollutants ,Air Pollution ,Halogenated Diphenyl Ethers ,medicine ,Environmental Chemistry ,Potential source ,Cities ,Waste Management and Disposal ,Flame Retardants ,0105 earth and related environmental sciences ,Air Pollutants ,Contribution function ,Chemistry ,Pollution ,Environmental chemistry - Abstract
This study collected 227 pairs of gas phase and particle phase air samples in a typical urban city of Northeast China from 2008 to 2013. Four alternative halogenated flame retardants for polybrominated diphenyl ethers (PBDEs) were analyzed, namely 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (EHTBB), bis (2-ethylhexyl) tetrabromophthalate (BEHTBP), syn-dechlorane plus (syn-DP) and anti-dechlorane plus (anti-DP). The average concentrations for EHTBB and BEHTBP were 5.2 ± 20 and 30 ± 200 pg/m3, respectively, while for syn-DP and anti-DPwere 1.9±5.1 and 5.8±18 pg/m3, respectively. Generally, they were frequently detected in the particle phase, and the gas/particle partitioning suggested they were the maximum partition chemicals. The fractional abundance of EHTBB (fEHTBB) and syn-DP (fsyn)were comparablewith those in other studies. Strong local sources were identified based on the air parcel backward trajectories and the potential source contribution function. The concentrations of these chemicals were significantly increased during this sampling campaign, possibly suggesting their increasing usages from 2008 to 2013 in China.
- Published
- 2016
- Full Text
- View/download PDF
32. A preliminary compilation and evaluation of a comprehensive emission inventory for polychlorinated biphenyls in China
- Author
-
Li-Yan Liu, Qiang Fu, Wei-Wei Song, Wan-Li Ma, Yi-Fan Li, and Song Cui
- Subjects
Air Pollutants ,China ,Environmental Engineering ,Air pollution ,Models, Theoretical ,medicine.disease_cause ,Polychlorinated Biphenyls ,Pollution ,Congener ,Air pollutants ,Air Pollution ,Monitoring data ,Environmental chemistry ,Environmental behavior ,Environmental monitoring ,medicine ,Environmental Chemistry ,Environmental science ,Emission inventory ,Longitude ,Waste Management and Disposal ,Environmental Monitoring - Abstract
Emission inventories for polychlorinated biphenyls (PCBs) are crucial input data for atmospheric transport modeling and for the study of source-receptor relationships and the environmental behavior of these chemicals. Three types of primary PCB sources are considered in this study: intentionally produced PCBs (IP-PCBs), unintentionally produced PCBs (UP-PCBs), and PCB emissions from two e-waste sites (EW-PCBs). This study presents the historical emissions of all IP-, UP- and EW-PCBs into the air in China and the gridded Chinese emission inventories at a resolution of 1/6° latitude×1/4° longitude from 1950 to 2010. The UP-TPCB emissions from 1950 to 2010 were re-estimated to be 8.56t from eight emission sources comprising 96.3% of the Chinese UP-TPCB emissions. The EW-TPCB emissions from 1990 to 2010 were estimated to be 103.5 t, of which 7.1t and 12.3t were EW-PCB28 and EW-7PCB congeners (i.e., indicator-PCB28, 52, 101, 118, 138, 153, 180), respectively. The IP-PCB28 and IP-7PCB congener emissions from 1965 to 2010 were estimated to be 57.4 t and 130.1t, respectively. A significant correlation was found between congener PCB28 and 7PCBs (R(2)=0.988 and P=0.000), which suggests that PCB28 is a good marker congener for describing the emission trends of all 7PCB emission sources. The gridded emission data were compared with published measured atmospheric concentrations for 2004 and 2008, and a significant correlation was found between the modeled emissions and monitoring data. To our knowledge, this study presents the first comprehensive gridded emission inventories that include all IP-, UP-, and EW-PCBs on a national scale.
- Published
- 2015
- Full Text
- View/download PDF
33. Brominated flame retardants in Chinese air before and after the phase out of polybrominated diphenyl ethers
- Author
-
Yi-Fan Li, Hong Qi, Mohammed O.A. Mohammed, Zhi Zhang, Wan-Li Ma, Wen-Long Li, Wei-Wei Song, Li-Yan Liu, and Zi-Feng Zhang
- Subjects
Atmospheric Science ,Air monitoring ,Polybrominated diphenyl ethers ,Chemistry ,Environmental chemistry ,Phase (matter) ,Detection rate ,Total variability ,General Environmental Science - Abstract
Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and novel non-BDE flame retardants (NBFRs), were analyzed in Chinese air during China's POPs Soil and Air Monitoring Program Phase I (SAMP-I) and Phase II (SAMP-II). The levels of Σ12PBDEs and Σ6NBFRs in urban sites were significantly higher than those in rural sites and background sites. The higher detection rate and concentrations of high molecular weight PBDEs and NBFRs in Phase II indicated the changing of the commercial pattern of BFRs after the phase out of PBDEs in China. Temperature was the major factor affecting the seasonal variations of molecular weight BFRs in atmosphere. A significant correlation between BFRs concentration and gross domestic product (GDP) was observed, with the GDP parameter explained 59.4% and 72.7% of the total variability for Octa-BDEs and low molecular weight NBFRs, respectively. Our findings indicated an evolving commercial usage of BFRs from SAMP-I to SAMP-II, i.e. shifting from lower molecular weight to higher molecular weight congeners in China.
- Published
- 2015
- Full Text
- View/download PDF
34. Benzonphenone-type UV filters in urine of Chinese young adults: Concentration, source and exposure
- Author
-
Yi-Fan Li, Ling Jiang, Chong-Jing Gao, Kurunthachalam Kannan, Ning-Zheng Zhu, Wan-Li Ma, and Li-Yan Liu
- Subjects
Adult ,Male ,China ,Adolescent ,Health, Toxicology and Mutagenesis ,Urinary system ,Sunscreening Agents ,Urine ,Toxicology ,Excretion ,Benzophenones ,Young Adult ,chemistry.chemical_compound ,Animal science ,Benzophenone ,Humans ,Young adult ,Chromatography ,Chemistry ,Significant difference ,General Medicine ,Pollution ,Female ,Rural population ,Environmental Monitoring - Abstract
Benzophenone (BP)-type UV filters are commonly used in our daily life. 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-HBP), 2,4-dihydroxy benzophenone (BP-1), 2,2',4,4'-tetrahydroxy benzophenone (BP-2) and 2,2'-dihydroxy-4-methoxy benzophenone (BP-8) were measured in urine samples from Chinese young adults. The results indicated that Chinese young adults were widely exposed to BP-3, BP-1, and 4-HBP, with the median concentrations of 0.55, 0.21, and 0.08 ng/mL, respectively. No significant difference was found between males and females, between urban and rural population. The correlations between urinary concentrations provided important indications for sources and metabolic pathways of target compounds. The estimated daily excretion doses of BP-3, 4-HBP, BP-1, BP-2 and BP-8 were 27.2, 2.24, 5.86, 0.76 and 0.30 ng/kg-bw/day, respectively. The ratio of exposure to excretion must be considered for the exposure assessment with chemicals based on urine measurement. This is the first nationwide study on BP-derivatives with young adults in China.
- Published
- 2015
- Full Text
- View/download PDF
35. Polybrominated diphenyl ethers (PBDEs) in the indoor dust in China: Levels, spatial distribution and human exposure
- Author
-
Wei-Wei Song, Wan-Li Ma, Li-Yan Liu, Ning-Zheng Zhu, Hong Qi, Wen-Long Li, and Yi-Fan Li
- Subjects
Adult ,China ,Adolescent ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Infant ,Dust ,Environmental Exposure ,General Medicine ,Spatial distribution ,Pollution ,Young Adult ,Congener ,Polybrominated diphenyl ethers ,Human exposure ,Air Pollution, Indoor ,Child, Preschool ,Environmental chemistry ,Halogenated Diphenyl Ethers ,Humans ,Environmental science ,Winter season ,Child ,Flame Retardants - Abstract
Indoor environment is an important source of human exposure to several toxicants, such as brominated flame retardants. Indoor dust samples were collected in winter season in 2010, which covered 23 provinces across China, for the analysis of polybrominated diphenyl ethers (PBDEs). Concentrations of PBDEs (Σ14PBDEs) ranged from 8.92 to 37,500 ng/g, with the mean of 3520 ng/g. BDE-209 was the most dominate congener, followed by BDE-183, BDE-47 and BDE-99. PBDE concentrations and the longitude were significantly correlated (p0.05), which was consistent with the status of social-economic development and human activities. The results of exposure to PBDEs through dust ingestion and dermal absorption indicated that the toddlers had the highest exposure dose, with the median value of 6.0 ng/kg-bw/day. According to the hazard quotients, health risk of PBDEs via dust ingestion in China is currently acceptable. Monte Carlo simulation was implemented to quantify the uncertainty and sensitivity of exposure models for determining the most influential variables. The results suggested that more specific and accurate parameters should be used for dust ingestion and dermal absorption exposure models in future.
- Published
- 2015
- Full Text
- View/download PDF
36. Concentrations and sources of polycyclic aromatic hydrocarbons in indoor dust in China
- Author
-
Li-Yan Liu, Feng Zhang, Hong Qi, Wan-Li Ma, Wen-Long Li, Ning-Zheng Zhu, and Yi-Fan Li
- Subjects
China ,Principal Component Analysis ,Environmental Engineering ,business.industry ,Cooking methods ,Traffic emission ,Coal combustion products ,Dust ,Pollution ,Key factors ,Southern china ,Air Pollution, Indoor ,Environmental chemistry ,Traffic conditions ,Environmental Chemistry ,Environmental science ,Coal ,Polycyclic Aromatic Hydrocarbons ,business ,Waste Management and Disposal ,Environmental Monitoring - Abstract
Indoor dust samples were collected across China in the winter of 2010 from 45 private domiciles and 36 public buildings. 16 polycyclic aromatic hydrocarbons (PAHs) were determined by GC-MS. Total concentrations of PAHs ranged from 1.00 μg/g to 470 μg/g with a mean value of 30.9 μg/g. High-molecular weight (HMW) PAHs (4 to 6 rings) are the predominant PAHs found in indoor dust, accounting for 68% of the total PAH concentration in private domiciles, and 84.6% in public buildings. Traffic conditions and cooking methods were the two key factors controlling PAH levels, especially for coal combustion and vehicular traffic emission sources. A significant positive correlation was observed between PAH concentrations in indoor dust and based on location (latitude and longitude). The latitudinal distribution indicated a higher usage of coal for heating in Northern China than in Southern China. The longitudinal distribution indicated that the usage of oil and mineral fuels as well as economic development and population density increased from West China to East China. In addition, diagnostic ratios and principal component analysis (PCA) were used to explore source apportion, as indicated in both the pyrogenic and petrogenic sources of PAHs in indoor dust in China. Furthermore, the BaP equivalent was applied to assess the carcinogenic risk of PAHs, which also indicated that traffic emissions and coal combustion were the two major contributions to carcinogenic risk of PAHs in indoor dust in China.
- Published
- 2014
- Full Text
- View/download PDF
37. PAHs in Chinese atmosphere: Gas/particle partitioning
- Author
-
Fu-Jie Zhu, Hongliang Jia, Li-Yan Liu, Yi-Fan Li, Meng Yang, and Wan-Li Ma
- Subjects
Environmental Engineering ,Molar mass ,010504 meteorology & atmospheric sciences ,010501 environmental sciences ,Particulates ,01 natural sciences ,Pollution ,Monitoring program ,Gas phase ,Atmosphere ,Orders of magnitude (specific energy) ,Phase (matter) ,Environmental chemistry ,Environmental Chemistry ,Environmental science ,Particle ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
The gas/particle (G/P) partitioning behavior is an important factor for the environmental fate of polycyclic aromatic hydrocarbons (PAHs) in atmosphere. Based on one year monitoring program at 11 urban sites across China, 7647 pairs of gaseous and particulate concentrations were obtained for 16 priority PAHs, which provided a good opportunity to study the G/P partitioning behavior of PAHs. The concentrations of PAHs in both gas and particle phases were not in the same level among the 11 sites with a difference of more than one orders of magnitude. Along with the increase of molar weight of PAHs, the proportion of concentration in particle phase was increasing. In particle phase, the concentrations of ∑16PAHs in northern Chinese cities were significantly (p
- Published
- 2019
- Full Text
- View/download PDF
38. Emission of unintentionally produced polychlorinated biphenyls (UP-PCBs) in China: Has this become the major source of PCBs in Chinese air?
- Author
-
Wei-Wei Song, Song Cui, Hong Qi, Yi-Fan Li, Wan-Li Ma, Li-Yan Liu, Yong-Sheng Ding, and Hongliang Jia
- Subjects
Atmospheric Science ,Engineering ,education.field_of_study ,business.industry ,Population ,Environmental engineering ,Latitude ,Atmosphere ,Environmental protection ,Distribution pattern ,China ,business ,Longitude ,education ,General Environmental Science - Abstract
There are two kinds of primary emissions of PCBs to the atmosphere; one is primary emissions due to intentionally produced PCBs (IP-PCBs), and the other is due to unintentionally produced PCBs (UP-PCBs). This paper presents UP-PCB emissions in China from 1950 to 2010. The total UP-PCB emissions in the 61 years were estimated to be 146.1 t, approximately 98.1% of which were from cement (132.5 t) and steel industries (6.3 t). The emissions from Chinese coking industry were 115 kg from 1950 to 2010, less than 0.1% of the total UP-PCB emissions in China. Both the temporal and spatial trends of these UP-PCB emissions were investigated. The UP-PCB emissions started to increase quickly at the middle of 1980s due to the fast and continuously developing cement and steel industries in China, and exceeded IP-PCB emissions possibly during the beginning of 2000s. The spatial pattern of UP-PCB emissions was in general consistent with the population distribution pattern, indicating the anthropogenic nature of the UP-PCB emissions. The gridded Chinese emission inventories for UP-PCBs from cement and steel industries on a 1/6° latitude and 1/4° longitude resolution were also compiled. The gridded UP-PCB emissions in 2005 were compared with PCB air concentrations measured by our group (IJRC-PTS) in 2005, and a significant correlation between these 2 datasets was found for the rural sites, but not for the urban sites. It is most likely that these UP-PCB emissions were a major source for PCB in Chinese rural air, and possibly responsible for the increase of PCBs in Chinese air as a whole from 2004 to 2008, reported in recent publications. To our knowledge, this is the first dataset of the Chinese UP-PCB emissions spanning 61 years from 1950 to 2010, and also the first gridded emission inventories for UP-PCBs on a national scale.
- Published
- 2013
- Full Text
- View/download PDF
39. Temporal variations of organochlorine pesticides in precipitation in Beijing, China
- Author
-
Guosheng Yang, Li-Yan Liu, Yongbao Zhang, Lingling Ma, Diandou Xu, Yang Chen, Hongliang Jia, and Zhifang Chai
- Subjects
Atmospheric Science ,Organochlorine pesticide ,Sampling (statistics) ,Chlordane ,Particulates ,Sedimentary depositional environment ,chemistry.chemical_compound ,Flux (metallurgy) ,Beijing ,chemistry ,Environmental chemistry ,Environmental science ,Precipitation ,General Environmental Science - Abstract
Temporal variations of organochlorine pesticides (OCPs) were determined in precipitation and monthly depositional fluxes were calculated in Beijing from February 2009 to March 2011. Compounds which were detected most often included α-HCH and β-HCH, and the volume-weighted mean (VWM) concentration of hexachlorocyclohexanes (HCHs) was 33.0 ng L −1 , accounting for 72.3% of the ∑OCPs in precipitation. The total concentrations of OCPs ranged from 3.73 to 152 ng L −1 (mean: 29.7 ± 3.5 ng L −1 ) for dissolved phase and from 1.61 to 114 ng L −1 (mean: 15.9 ± 2.0 ng L −1 ) for particulate phase, respectively. OCPs in dissolved phase dominated sampled concentrations in precipitation (HCHs: 71.8%, Chlordane: 77.7%, dichlorodiphenyltrichloroethanes-DDTs: 50.1%) with an exception of hexachlorobenzene–HCB (26.3%). Furthermore, the distribution coefficient, K pd , was generally large in low temperature, especially in spring. The abundance of ∑OCPs in the precipitation fluctuated monthly, with high value in late winter and spring. The past farmland near the sampling site was under construction during sampling, which may be an important local re-emission source in this study. The elevated wet deposition flux of 11 selected OCPs was 14.9 μg m −2 yr −1 in Beijing.
- Published
- 2012
- Full Text
- View/download PDF
40. Temporal trends of polychlorinated biphenyls in precipitation in Beijing, China
- Author
-
Guosheng Yang, Zhifang Chai, Yang Chen, Hongliang Jia, Li-Yan Liu, Lingling Ma, Yongbao Zhang, and Diandou Xu
- Subjects
Atmosphere ,Atmospheric Science ,Flux (metallurgy) ,Beijing ,Environmental chemistry ,Environmental science ,Precipitation ,Particulates ,Contamination ,Snow ,Scavenging ,General Environmental Science - Abstract
Temporal trend of polychlorinated biphenyls (PCBs) was determined in precipitation and monthly depositional fluxes were calculated in Beijing for the first time from February 2009 to March 2011. Total PCBs concentrations ranged from 7.00 to 993 ng L-1 in dissolved phase and from 1.00 to 133 ng L-1 in particulate phase, with a two orders of magnitude variation. Concentrations of PCBs were dominated by dissolved phase, which accounted for 82.5% of the total PCBs in precipitation, implying PCBs enrichment in rainwater due to efficient scavenging of highly contaminated gas phase and nonfilterable submicron particles which easily adsorbed organic contaminants in urban atmosphere. Highest concentrations of PCBs were measured in snow, which were about two times higher than those in rainwater, demonstrating more efficient scavenging of PCBs by snow. The sum of bi-, tri- and tetrachlorinated congeners accounted for 70.5% of total PCBs in precipitation, suggesting that PCBs mainly come from the historical usage of domestic PCB product, e.g., trichlorobiphenyl. PCBs concentrations in both dissolved and particulate phases showed slow rate of decline, with a half-life of 16.9 years in precipitation, suggesting that the atmospheric concentrations of PCBs were decreasing slowly in Beijing. The wet deposition flux of Sigma PCBs ranged from 0.240 to 6.55 mu g m(-2) month(-1) (mean: 1.41 mu g m(-2) month(-1)), indicating a relatively high level of PCBs contamination in Beijing atmosphere. (C) 2012 Elsevier Ltd. All rights reserved.
- Published
- 2012
- Full Text
- View/download PDF
41. Levels and speciation of arsenic in the atmosphere in Beijing, China
- Author
-
Zhifang Chai, Li-Yan Liu, Tingting He, Lingling Ma, Jie Li, Diandou Xu, Yang Chen, Hongliang Jia, Yongbao Zhang, and Guosheng Yang
- Subjects
Risk ,China ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Respiratory System ,chemistry.chemical_element ,High-performance liquid chromatography ,Atomic fluorescence spectrometry ,Arsenic ,Atmosphere ,Suspensions ,Beijing ,Neoplasms ,Environmental Chemistry ,Weather ,media_common ,Chemistry ,Suspended particles ,Public Health, Environmental and Occupational Health ,Environmental Exposure ,General Medicine ,General Chemistry ,Environmental exposure ,Pollution ,Speciation ,Environmental chemistry ,Environmental Pollutants - Abstract
Arsenic levels and speciation in the total suspended particles (TSPs) were quantitatively determined by high performance liquid chromatography on-line coupled with hydride generation atomic fluorescence spectrometry in Beijing, China from February 2009 to March 2011. The high TSP levels fluctuated between 0.07 and 0.79 mg m(-3), with a mean level of 0.32 +/- 0.17 mg m(-3). The total arsenic concentrations ranged from 0.03 to 0.31 mu g m(-3) (mean: 0.13 +/- 0.06 mu g m(-3)) in Beijing's air. The concentrations of As(III) and As(V) ranged from 0.73 to 20 ng m(-3) (mean: 4.7 +/- 3.6 ng m(-3)) and from 14 to 2.5 x 10(2) ng m(-3) (mean: 67 35 ng m-3), respectively. As levels and speciation demonstrated relative higher levels in spring and autumn and lower values in summer and winter. As(V) accounted for 81-99% of the extractable species in the TSP samples which showed that As(V) was the major fraction of the extractable As. Organoarsenic species, monomethylarsonate (MMA) and dimethylarsinate (DMA) were not found in all samples. Higher values of enrichment factors demonstrated that arsenic in TSP mainly come from anthropogenic sources. High As and its species levels in air and respiratory exposure (0.30-0.84 mu g d(-1)) attributed to higher excess cancer risk ((4.2 +/- 2.0) x 10(-4)) for people in Beijing. (C) 2012 Elsevier Ltd. All rights reserved.
- Published
- 2012
- Full Text
- View/download PDF
42. Modeling redistribution of α-HCH in Chinese soil induced by environment factors
- Author
-
Chongguo Tian, Jianhui Tang, Yi-Fan Li, Li-Yan Liu, and Jianmin Ma
- Subjects
China ,Health, Toxicology and Mutagenesis ,Toxicology ,Sink (geography) ,Soil ,Soil Pollutants ,Weather ,geography ,geography.geographical_feature_category ,Ecology ,Eastern china ,Temperature ,Wind field ,General Medicine ,Soil carbon ,Contamination ,Pesticide ,Pollution ,Carbon ,Kinetics ,Models, Chemical ,Soil water ,Environmental science ,Physical geography ,Environmental Pollution ,Hexachlorocyclohexane ,Environmental Monitoring - Abstract
This study explores long-term environmental fate of α-HCH in China from 1952 to 2007 using ChnGPERM (Chinese Gridded Pesticide Emission and Residue Model). The model captures well the temporal and spatial variations of α-HCH concentration in Chinese soils by comparing with a number of measured data across China in different periods. The results demonstrate α-HCH grasshopping effect in Eastern China and reveal several important features of the chemical in Northeast and Southeast China. It is found that Northeast China is a prominent sink region of α-HCH emitted from Chinese sources and α-HCH contamination in Southwest China is largely attributed to foreign sources. Southeast China is shown to be a major source contributing to α-HCH contamination in Northeast China, incurred by several environmental factors including temperature, soil organic carbon content, wind field and precipitation.
- Published
- 2011
- Full Text
- View/download PDF
43. Dechlorane plus in multimedia in northeastern Chinese urban region
- Author
-
Wan-Li Ma, Li-Yan Liu, De-Zhi Sun, De-Gao Wang, Yi-Fan Li, Hong Qi, and Ji-Min Shen
- Subjects
China ,Geologic Sediments ,Soil test ,Fresh Water ,Soil ,chemistry.chemical_compound ,Dry weight ,Hydrocarbons, Chlorinated ,Polycyclic Compounds ,Cities ,Water pollution ,lcsh:Environmental sciences ,Flame Retardants ,General Environmental Science ,lcsh:GE1-350 ,Hydrology ,Persistent organic pollutant ,Soil chemistry ,Sediment ,Dechlorane plus ,Soil contamination ,chemistry ,Environmental chemistry ,Environmental science ,Environmental Pollutants ,Great Lakes Region ,Environmental Pollution ,Environmental Monitoring - Abstract
Dechlorane plus (DP) was quantified by gas chromatography/mass spectrometry (GC/MS) in soil and ambient air (collected from Harbin City, a typical northeastern Chinese urban region), water and sediment samples (collected in the segment within Harbin of Songhua River, located in northeast of China). The average concentrations of DP in sediment and soil samples were 123.6 pg g−1 dry weight (dw), and 11.3 pg g−1 dw, respectively. However, the concentration of DP in water was below the method detection limit (MDL). The inter-media comparison between water and sediment suggested that the sediment may be a receptor for DP. For air samples, two methods were used for collecting air in order to compare, active air sampling (AAS) and passive air sampling (PAS). The average concentrations of DP were 0.4 pg m−3 and 6.9 pg m−3 for AAS and PAS samples, respectively. Discrepancies of deployment period and different calculated method for DP concentration may help to explain the remarkable difference between PAS and AAS. Overall, DP in all matrices in Harbin City showed lower concentrations than that in the Great Lakes region. The anti-DP isomer was consistently greater than that of the syn-DP isomer in all matrices. The average fractional abundance of the syn-DP isomer (fsyn) was smaller than the technical DP composition (fsyn=0.35) according to other studies in the Great Lakes region. As we know, this study is the first attempt to comprehensively study DP concentrations in four different matrices (water, ambient air, sediment and soil) in China. Keywords: Dechlorane plus, Water, Sediment, Soil, Air, China
- Published
- 2011
- Full Text
- View/download PDF
44. Seasonal variations of sources of polycyclic aromatic hydrocarbons (PAHs) to a northeastern urban city, China
- Author
-
De-Zhi Sun, Hong Qi, De-Gao Wang, Wan-Li Ma, Yi-Fan Li, and Li-Yan Liu
- Subjects
Pollution ,China ,Environmental Engineering ,Correlation coefficient ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Air pollution ,medicine.disease_cause ,Chine ,Air Pollution ,medicine ,Environmental Chemistry ,Coal ,Cities ,Polycyclic Aromatic Hydrocarbons ,Vehicle Emissions ,media_common ,Principal Component Analysis ,Persistent organic pollutant ,business.industry ,Public Health, Environmental and Occupational Health ,Environmental engineering ,General Medicine ,General Chemistry ,Particulates ,Seasonality ,medicine.disease ,Environmental chemistry ,Environmental science ,Seasons ,business ,Environmental Monitoring ,Power Plants - Abstract
Understanding the seasonal variations of sources of polycyclic aromatic hydrocarbons (PAHs) in air in urban region is important to the effective control of air pollution in the region. Based on a year round dataset (from August 2008 to July 2009), the sources of atmospheric PAHs in Harbin, a typical Chinese northeastern urban city, were analyzed by principal component analysis (PCA) and positive matrix factorization (PMF). The average total (gas plus particulate) PAH concentration varied from 6.3 ng m −3 to 340 ng m −3 with a mean of 100 ± 94 ng m −3 , with higher concentrations in heating season than those in non-heating season. PCA and PMF identified similar source factors to atmospheric PAHs with obvious seasonal variation. The results obtained by PMF method indicated that the main sources were coal-fired boiler (39%), diesel engine (34%) and coal average (22%) in heating season and traffic emissions (59%), ground evaporation (18%) and coal average (17%) in non-heating season. Excellent correlation coefficients between predicted and measured concentrations of PAHs indicated that PMF was a useful model for source apportionment of PAHs in atmosphere.
- Published
- 2010
- Full Text
- View/download PDF
45. Energy fluctuation and correlation in Tsallis statistics
- Author
-
Zhi-Hui Feng and Li-Yan Liu
- Subjects
Statistics and Probability ,Physics ,Correlation ,Particle number ,Tsallis entropy ,Maxwell–Boltzmann statistics ,Tsallis statistics ,Condensed Matter::Statistical Mechanics ,Particle ,Statistical physics ,Condensed Matter Physics ,Ideal gas ,Energy (signal processing) - Abstract
We investigate the fluctuation of the energy in the framework of Tsallis statistics and find the correlation plays an important role in energy fluctuations. In Tsallis statistics, the correlation is induced by the nonextensivity of Tsallis entropy and exists between particles even if the particles are dynamically independent. By taking the generalized ideal gas as an example, we get that when the particle number N is large enough, the relative fluctuation of the energy is proportional to 1 / N instead of 1 / N in Boltzmann statistics. Thus, the relative energy fluctuation is much smaller in Tsallis statistics than that in Boltzmann statistics. Besides, we demonstrate that the introduction of correlation between particle energies leads to smaller energy fluctuations in Tsallis statistics.
- Published
- 2010
- Full Text
- View/download PDF
46. A modeling assessment of association between East Asian summer monsoon and fate/outflow of α-HCH in Northeast Asia
- Author
-
Chongguo Tian, Jianmin Ma, Yi-Fan Li, Hongliang Jia, Diandou Xu, and Li-Yan Liu
- Subjects
Atmosphere ,Atmospheric Science ,Oceanography ,Deposition (aerosol physics) ,Climatology ,Front (oceanography) ,Environmental science ,East Asian Monsoon ,Outflow ,East Asia ,Monsoon ,Rainband ,General Environmental Science - Abstract
Using a dynamic numerical atmospheric transport model for organochlorine pesticides (OCPs), the relationship between the East Asian summer monsoon and the fate of α-hexachlorocyclohexane (α-HCH), a banned OCP, in the atmosphere over Northeast Asia was investigated and assessed. The modeled temporal and spatial patterns and variability of α-HCH air concentrations during the summer months of 2005 revealed a strong link between this chemical in the atmosphere over Northeast Asia and the East Asian summer monsoon. At lower atmospheric levels, easterly and southeasterly winds blowing from relatively cold ocean surface convey α-HCH air concentration from southeast China to northeast China. A monsoon front extending from southeast China to Japan, characterized by a strong wind convergence, carried the air concentration to a high elevation of the atmosphere where it was delivered by southerly monsoon flow to northern China and North Pacific Ocean. This summer monsoon associated northward atmospheric transport caused a reversal of the soil/air exchange from outgassing to net deposition during spring–summer period. The modeled wet deposition fluxes of α-HCH agreed well with the changes in the typical summer monsoon rain bands, designated as Meiyu in China, Changma in Korea, and Baiu in Japan. The major wet deposition flux paralleled with the monsoon front as well as the monsoon rain bands. The temporal change in the fluxes exhibits abrupt northward advances, which is associated with a stepwise northward and northeastward advance of the East Asian summer monsoon. The modeled α-HCH outflow in the atmosphere from China occurs mostly in the summer months and through northeast China, featured strongly by the evolution of the summer month. This study suggests that the East Asian summer monsoon provides a major atmospheric pathway and summer outflows to α-HCH over East Asia.
- Published
- 2009
- Full Text
- View/download PDF
47. Synthesis of K0.3WO3 tungsten bronze with gaseous permeation of K3PW12O40 by Sm and electrical properties of K0.3WO3 tungsten bronze
- Author
-
Li Yan Liu, Yun Peng Wang, and Bai Bin Zhou
- Subjects
Chemistry ,Mechanical Engineering ,Metals and Alloys ,Analytical chemistry ,Infrared spectroscopy ,chemistry.chemical_element ,Permeation ,engineering.material ,Tungsten ,Conductivity ,Keggin structure ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,Mechanics of Materials ,Materials Chemistry ,engineering ,Inductively coupled plasma ,Bronze ,Nuclear chemistry - Abstract
The permeation of the rare earth element Sm to the heteropoly compound K 3 PW 12 O 40 using the rare earth gas phase-heated diffused permeation method at 550 °C is reported for the first time. The studies of infrared spectroscopy (IR) and X-ray diffraction (XRD) indicate that the Keggin structure of the compound is destroyed. The bond of W–O–W is broken and tungsten bronze K 0.3 WO 3 is produced after permeation. Inductively coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS) were used to determine the percentage composition of the Sm in a permeated sample. The result shows that there is Sm in a permeated sample and Sm interacts with the other component of the compound. Conductivity of compounds before and after permeation was investigated by four-electrode method. It reveals that the conductivity of the permeated sample is 4.18 × 10 −4 S cm −1 , which is 1000 times higher than that of the original sample.
- Published
- 2008
- Full Text
- View/download PDF
48. DNA Biosensor Prepared by Electrodeposited Pt-nanoparticles for the Detection of Specific Deoxyribonucleic Acid Sequence in Genetically Modified Soybean
- Author
-
Xiao-Yan Du, li-Yan Liu, Xian-Chen Jiang, Qian Sun, and Mao-Qing Wang
- Subjects
Detection limit ,chemistry.chemical_compound ,chemistry ,Complementary DNA ,Electrode ,Analytical chemistry ,Electrochemistry ,Platinum nanoparticles ,Biosensor ,Genetically modified soybean ,DNA ,Analytical Chemistry ,Nuclear chemistry - Abstract
DNA biosensors were prepared by electrodepositing platinum nanoparticles (Pt-nano) on the surface of a glassy carbon electrode (GCE). A 19-mer ssDNA of promoter 35S, which was specific to most inserted sequences in genetically modified food, was immobilized on the Pt nanoparticle-deposited GC electrode. The morphology of the surface of Pt nanoparticle-deposited GC electrodes (Pt-nano/GCE) was investigated under a scanning electron microscope. The electrochemical response of the sensor to the complementary DNA was studied with [Co(phen)3]3+ ion (phen = 1,10-phenanthroline), as an electrochemical indicator. The response of the Pt nanoparticle-deposited GC electrode was significantly higher when compared with that of an electrode prepared based on a bare GC electrode of the same geometric surface area. A linear calibration graph for the complementary DNA over a concentration range of 2.14 × 10−9−2.14 × 10−7 M was obtained and the limit of detection was 1.0 × 10−9 M, whereas, almost no response was observed for the three-base-mismatched DNA. The detection response of the sample DNA digested by restricted enzyme (Hind?) was higher than that of the undigested sample DNA. When the DNA sensors were used for the determination of concentration of the DNA sequence extracted from the genetically modified soybean sample, the results were satisfactory. The relative standard deviation was 5.89% for the extracted sample DNA (n = 5). The DNA sensor could be used eight times repeatedly without deterioration.
- Published
- 2008
- Full Text
- View/download PDF
49. Analysis of JAG1 gene variant in Chinese patients with Alagille syndrome
- Author
-
Xinzhi Zhao, Qinghe Xing, Jian-She Wang, Lin He, Xiao-Hong Wang, Qiaoli Li, Yun Liu, Zhiyun Wei, Honglian Wang, Lei Wang, Li-Yan Liu, and Shiting Chen
- Subjects
JAG1 ,DNA Mutational Analysis ,Notch signaling pathway ,Biology ,Polymorphism, Single Nucleotide ,Serrate-Jagged Proteins ,Asian People ,Alagille syndrome ,Genetics ,medicine ,Extracellular ,Humans ,Receptor, Notch2 ,Child ,Gene ,Genetic Association Studies ,Calcium-Binding Proteins ,Membrane Proteins ,General Medicine ,medicine.disease ,Protein Structure, Tertiary ,Alagille Syndrome ,Membrane protein ,Case-Control Studies ,Child, Preschool ,Intercellular Signaling Peptides and Proteins ,Jagged-1 Protein - Abstract
Alagille syndrome (AGS) is an autosomal dominant disorder characterized by bile duct paucity. It can be caused by variations in the JAG1 gene encoding a protein of Notch ligand and by variations in the NOTCH2 gene encoding a Notch receptor. In this study we identified 15 different JAG1 gene variations in 17 Chinese patients, nine of which were novel alterations including c.766G > T, c.819delC, c.826delT, c.3099_3100delCA, c.1323_1326delCTGG, c.1771_1775delGTGCGinsT, c.1868delG, c. 2791_2792insA and c.866delG. These alterations were located in the extracellular domain of JAG1, in particular in the DSL and EGF-like repeat domain. All the specific variations in five inheritance cases investigated were de novo. Furthermore, no sequence variation of NOTCH2 was detected in JAG1 alteration negative patients.
- Published
- 2012
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.