@phdthesis{oai:sucra.repo.nii.ac.jp:00019822, author = {XIAO, KAI}, month = {}, note = {VIII, 161p, Lung cancer has unique epidemiological characteristics due to the toxicity of indoor residential coal combustion (RCC) particles in Xuanwei, which suggests that there may be unique molecular mechanisms for the development of lung cancer in Xuanwei. However, mechanism of the high lung incidence is still not clear. After an extensive literature survey, we found that the risks posed by PM have been extensively researched, but the risk attribution of specific components of atmospheric particulate matters (APMs) is far from being fully understood. Observations of EPFRs in PM may provide the key to understanding the carcinogenic behaviour of these particles. To our knowledge, RCC and residential biomass combustion (RBC), and APMs are considered an important sources of EPFRs and HULIS, furthermore, there is few information available for personal exposure levels to inhaled EPFRs and HULIS in high lung cancer incidence areas of Xuanwei, China. Therefore there is a need to assess exposure to EPFRs and HULIS. In this study, we selected six kinds of coal and three kinds of biomass in Xuanwei, then conducted simulated combustion experiments, and six group of APMs using an Andersen high volume air sampler to explore the content and particle size distribution pattern of EPFRs and HULIS and health risk assessment of EPFRs and HULIS in particulate matter produced by different sources, providing new perspectives and evidence to reveal the high incidence of lung cancer in Xuanwei. Comparing the different type particulate matter, we found that the mass concentration of particulate matter emitted from solid fuel combustion was mainly concentrated in particle size < 2.0 μm (58.17 ± 3.59 % for RBC particles, 67.02 ± 9.06 % for RCC particles), while the mass concentrations of atmospheric particulate matter were mainly concentrated in the particle size < 2.0 μm (49.74 ± 2.15 %) and >7.0 μm (20.28 ± 3.29 %). It indicates that the emission of fine particulate matter from raw coal combustion is more than that from biomass combustion, and the health risk is not negligible as the ambient atmosphere is dominated by fine particulate matter. We found that the mass of atmospheric particles showed a bimodal distribution, with the major peak in the range of particle size <1.1 μm and the minor peak in the range of size >7 μm. In contrast, the concentration of particulate matter emitted from solid fuel combustion is mainly concentrated in the range of particle size <1.1 μm. Xuanwei area, there are no large sources of pollution in the vicinity of the sampling site, and its pollution may be caused by solid fuel combustion, road transport, dust from construction sites, exhaust emissions from cars or mining in the county, and long-distance transport of pollution from surrounding cities. Beijing area, it is generally acknowledged that primary source like road dust and soil as the main emission source of coarse particulate matter, while fine atmospheric particulate matters are emitted from both primary source and secondary formation due to complex chemical processes in the atmosphere. Predominantly, high PM in the winter in Beijing was mainly attributed to the adverse meteorological conditions like low temperature and lower boundary layer height, less precipitation and weaker wind and solid fuel (coal) combustion for indoor heating. another reason may be that probably due to the transport of polluted air masses from urban areas. The results show that the particulate matter pollution in Xuanwei is not serious and is at a medium level in the country, indicating that the mass concentration of particulate matter is not the main factor of lung cancer in Xuanwei, which may be due to the possibility that the local particulate matter in Xuanwei contains some special components or the content of certain pollutants exceeds the standard. The result are follows: APMs in Xuanwei: The average ratio of NO₃-/SO₄²- in all particulate were 0.22, 0.18, 0.15, 0.34 and 0.36, it indicating that stationary industrial and combustion sources contributed to PM were more significant. The ANE / CAE < 1 in all particulate indicate that the APMs was alkaline. SO₄²- prefers to combine with NH₄+ to form (NH₄)₂SO₄, which hinders the formation of NH₄NO₃, the remaining SO₄²- and NO₃- to neutralize the K+, KNO₃ was formed at all particulate. However, K₂SO₄ can only be formed in the particle size less than 3.3 μm. As and Se were identified as the most enriched (EF >10) WSPTMs in all PM sizes, were predominantly from anthropogenic emissions, suggesting that coal combustion could be the important contributor of PM-bound WSPTMs in this study area. Total WSPTMs exhibited high TCR values (9.98 × 10-⁶, 1.06 × 10-⁵, and 1.19 × 10-⁵ for girls, boys and adults, respectively) in the smaller particles (<1.1 μm). Se make a major contribution (63.60%) CR in PM₂.₀, furthermore decreased with the PM size increase and should be of more concern. RCC particulate matter：(1) HULIS-C to the PM were 2.09 %~5.65 % for PM₂.₀ and 2.68 %~5.62 % for PM₂.₀~₇.₀, respectively. HULIS-C emitted from RCC is mainly concentrated in PM₂.₀ (68.48 %~79.30 %). (2) During our measurements, the concentrations of HULIS-C and WSOC were significantly correlated with SO₄²-, NO₃, and NH₄ + in RCC particles. (3) HULIS-Cx to HULIS-Ct (%) values in RCC particles are 68.48 %―79.30 % (average 73.95 ± 5.13%) for PM₂.₀ and 20.70 %~34.27 (average 26.05 ± 5.13%) for PM₂.₀~₇.₀, respectively. The HULIS-Cx to WSOCx (%) values in RCC particles are 32.73 %―63.76 % (average 53.85 ± 12.12%) for PM₂.₀ and 33.91%~82.67% (average 57.06 ± 17.32%) for PM₂.₀~₇.₀, respectively. (4) Our result show that all PMs, the TCR was higher than 1 for adults and lower than 1 for children, except for PM₁.₁. TCR values for As, Cd and Co decreased with increasing PM particle size (for adults and children), indicating that As, Cd and Co had the highest in PM₁.₁. Interestingly, the TCR values for Cr (VI) were stable across PM particle sizes with no variability (for adults and children), and the TCR for lead was negligible. Notably, the TCR values for V showed a bimodal distribution, with the major peak in the particle size <1.1 μm while the minor peak in the size range of >7 μm. The noncancer risk of Ba account for 91.28 %, 71.39 %, 78.74 %, 82.38 %, and 84.95 % within PM₁.₁, PM₁.₁-₂.₀, PM₂.₀-₃.₃, PM₃.₃-₇.₀, and PM>₇.₀. It indicates that the non-carcinogenic risk of WSPTMs in RCC particles, mainly Ba, followed by As and the non-carcinogenic risk is highest within PM₁.₁ in Xuanwei. (5) The mean g factors were ranged from 2.0016 to 2.0043, 2.0039 to 2.0043 and 2.0039 to 2.0046 for biomass combustion, coal combustion and APMs, respectively, indicating that the samples were mainly oxygen-centered radicals (phenoxyl and semiquinone radicals) in Xuanwei. (6) The potential health risks of EPFRs for adult and child in PM₁.₁ were equivalent to 130.31 ± 35.06, 49.52 ± 13.32 cigarettes in coal combustion particles, 53.11 ± 6.65, 20.18 ± 2.53 cigarettes in biomass combustion particles, and 80.02 ± 37.37, 30.41 ± 14.20 cigarettes in APMs, respectively. The results suggest that the health risk of EPFRs is significantly increased when the particle size distribution of EPFRs is taken into account, and RCC particulate matter is more hazardous to humans than APMs, followed by RBC particulate matter. Our results can help stakeholders and policy makers recognize the characteristics of anthropogenic particles and their impact on air quality in the region, and initiate strategies to further control emissions to improve public health. We recommend continuing efforts in controlling coal burning throughout the year and also to include the surrounding areas. In the future, a comprehensive investigation of coal combustion HULIS-C and EPFRs emissions under different stove types, combustion conditions and combustion stages are necessary to better understand HULIS-C. we should pay more attention to mechanism on the ROS generated by the HULIS and EPFRs through the cellular matrices and tissue. Some attempts should be done in cell-free and cell-based experiments to obtain well-characterized information about the ROS generated by the HULIS and EPFRs combination and to better address the health effects of HULIS and EPFRs., Abstract ............................................................................................................II Chapter 1 Introduction ...............................................................................................1 1.1 Purpose and significance of the study ..........................................................................1 1.2 Current Status of Lung Cancer Research in Xuanwei Region .......................................................4 1.3 The overview of air pollution ..................................................................................6 1.3.1 Particulate Matter .......................................................................................7 1.3.2 Sources of Particulate Matter ............................................................................7 1.3.3 Composition of Particulate Matter ........................................................................8 1.3.3.1 Water-Soluble Inorganic Ionic Species (WSIIs) ........................................................8 1.3.3.2 Potentially toxic metals (PTMs) ......................................................................9 1.3.3.3 Humic-like substances (HULIS) ........................................................................9 1.3.3.4 Environmental Persistent Free Radicals (EPFRs) ......................................................10 1.3.3.5 Humic-like substances (HULIS) .......................................................................11 1.3.4 Health Effects of Oxidative Stress Generated by Particulate Matter ......................................12 1.4 Main Research Content and Technical Route .....................................................................13 Chapter 2 Study area and sample collection ..........................................................................16 2.1 Location and Weather condition of the sampling site ...........................................................16 2.2 Civil houses and solid fuels at sampling sites ................................................................17 2.3 Sample collection .............................................................................................18 2.3.1 Sample Collection in Xuanwei ............................................................................18 2.3.1.1 Collection of Raw Coal and Biomass ..................................................................18 2.3.1.2 Collection of Atmospheric Particulate Matters in Xuanwei ............................................18 2.3.2 Collection of Atmospheric Particulate Matters in Beijing ................................................19 2.4 Sample processing and collection of simulated combustion particulate matter ...................................22 2.4.1 Instrument and materials ................................................................................22 2.4.2 Combustion devices ......................................................................................22 2.4.3 Sampling experiments ....................................................................................24 2.5 Calculation of particulate matter concentration ...............................................................24 2.6 Mass concentration of size-segregated particulate matters .....................................................25 2.6.1 Mass concentration of size-segregated in APMs in Xuanwei ................................................25 2.6.2 Mass concentration of size-segregated in RBC particles ..................................................28 2.6.2 Mass concentration of size-segregated particles in RCC particles ........................................31 2.6.3 Comparison of mass concentrations of particulate matter from different sources in Xuanwei ...............33 2.6.4 Mass concentration of size-segregated particles in APMs in Beijing ......................................34 2.6.4.1 Weather conditions during the Beijing sampling ......................................................34 2.6.4.2 The size distribution of APMs in Beijing ............................................................35 2.6.5 Differences in atmospheric particulate matter between Xuanwei and Yunnan ................................38 2.7. Brief summary ................................................................................................39 Chapter 3 Materials and methods .....................................................................................41 3.1 Ion Chromatography (IC) .......................................................................................41 3.1.1 Principle of IC .........................................................................................41 3.1.2 The advantages of IC ....................................................................................42 3.1.3 Applications of IC ......................................................................................43 3.1.4 Ion balance calculation .................................................................................43 3.1.5 Pre-treatment and analysis of Water-Soluble Inorganic Ionic Species (WSIIs) of samples ..................44 3.1.6 Required Instruments and Chemical Reagents in Experiment ................................................44 3.2 Inductively coupled plasma mass spectrometer (ICP-MS) .........................................................45 3.2.1 Principle of ICP-MS .....................................................................................45 3.2.2 The advantages of ICP-MS ................................................................................46 3.2.3 Applications of ICP-MS ..................................................................................46 3.2.4 Analysis of Potentially Toxic Metals (PTMs) and Water-Soluble Potentially Toxic Metals (WSPTMs) by ICP-MS .........................................................................................................46 3.2.5 Required Instruments and Chemical Reagents in Experiment ................................................47 3.3 Total Organic Carbon Analyzer (TOC) ...........................................................................48 3.3.1 Principle of Total Organic Carbon Analyzer (TOC) ........................................................48 3.3.2 The advantages of TOC Analyzer ..........................................................................49 3.3.3 Analysis of Humic Like Substances (HULIS) and Water-Soluble Organic Carbon (WSOC) .......................49 3.4 Electron Spin Resonance (ESR) .................................................................................51 3.4.1 Principle of Electron Spin Resonance (ESR) ..............................................................51 3.4.2 Applications of ESR .....................................................................................51 3.4.3 Detection of EPFRs ......................................................................................52 3.4.4 Data processing and calculation of the absolute number of spins .........................................52 Chapter 4 Result and Discussions ....................................................................................53 4.1 Water-Soluble Inorganic Ionic Species (WSIIs) .................................................................53 4.1.1 The Levels of Water-Soluble Inorganic Ionic Species (WSIIs) in APMs .....................................53 4.1.2 The Levels of Water-Soluble Inorganic Ionic Species (WSIIs) in APMs .....................................55 4.1.3 Ionic balance and neutralization of particulate acidity .................................................57 4.1.4 Water-Soluble Inorganic Ionic Species (WSIIs) in RCC particles ..........................................59 4.1.5 The mass concentration of water-soluble inorganic ionic species size distribution and sources in Beijing... .........................................................................................................63 4.2 Water-Soluble Potentially Toxic Metals ........................................................................65 4.2.1 The mass concentration of potential toxic metals size distribution APMs in Xuanwei ......................65 4.2.2 The mass concentration of potential toxic metals size distribution in Beijing ...........................68 4.3 Source-apportionment of heavy metals by crustal enrichment factors (CEFs) .....................................71 4.3.1 Source-apportionment of heavy metals by crustal enrichment factors of APMs in Xuanwei ...................72 4.3.2 Source-apportionment of heavy metals by crustal enrichment factors of APMs in Beijing ...................73 4.4 Health Risk Assessment of Water-Soluble Potentially Toxic Metals ..............................................74 4.4.1 Health Risk Assessment of Water-Soluble Potentially Toxic Metals in APMs in Xuanwei .....................77 4.4.2 Health Risk Assessment of Water-Soluble Potentially Toxic Metals in APMs in Beijing .....................81 4.4.3 Health Risk Assessment of Water-Soluble Potentially Toxic Metals in RCC Particles .......................87 4.3.4 Briefly Summary .........................................................................................93 4.5 The characteristics of EC, OC, WSOC, and HULIS-C in RCC particles .............................................94 4.5.1 Abundance of EC, OC, WSOC, and HULIS-C in RCC particles .................................................94 4.5.2 Size distribution of HULIS-C in RCC particles ...........................................................96 4.5.3 Correlation of HULIS-C and WSOC with other species in RCC particles .....................................98 4.6 The characteristics of EPFRs in RCC particles ................................................................100 4.6.1 EPFRs exposure evaluation ..............................................................................100 4.6.2 EPFRs and PM concentrations in atmospheric particulate matter and solid fuel combustion particles ......101 4.6.2.1 EPFRs and PM concentrations in biomass combustion particles ..........................................101 4.6.2.2 EPFRs and PM concentrations in coal combustion particles .............................................104 4.6.2.3 EPFRs and PM concentrations in atmospheric particulate matters .......................................106 4.6.3 EPFRs species characteristics ..........................................................................109 4.6.4 Potential health risk of EPFRs .........................................................................118 4.6.5 Brief summary ..........................................................................................120 Chapter 5 Summary, limitation and future work ......................................................................121 5.1 Summary of PM Concentration ..................................................................................121 5.2 Summary of APMs ..............................................................................................122 5.2.1 Summary of APMs in Beijing: ................................................................................122 5.2.2 Summary of APMs in Xuamwei: ................................................................................122 5.3 Xuanwei: .....................................................................................................123 5.3.1 Summary of WSPTMs ..........................................................................................123 5.3.2 Summary of HULIS: ..........................................................................................124 5.3.3 Summary of EPFRs: ..........................................................................................124 5.4 Limitations of the study .....................................................................................125 5.5 Policy Implications ..........................................................................................125 5.6 Future work ..................................................................................................125 Acknowledgments ....................................................................................................127 Abbreviations and symbols ..........................................................................................128 List of Figures ....................................................................................................131 List of Tables .....................................................................................................134 Published List During PH.D period ................................................................................136 Reference ..........................................................................................................137, 主指導教員 : 王青躍, text, application/pdf}, school = {埼玉大学}, title = {Characteristics and potential inhalation exposure risks of environmentally persistent free radicals and potentially toxic metal in atmospheric particulate matter and solid fuel combustion particles, China}, year = {2022}, yomi = {シャオ, カイ} }