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Short-term exposure to air pollution is associated with a decline in cognitive function. Standardized test scores have been employed to evaluate the effects of air pollution exposure on cognitive performance. Few studies aimed to prove whether air pollution is responsible for reduced test scores; none have implemented a “gold-standard” method for assessing the association such as a randomized, double-blind intervention. This study used a “gold-standard” method─randomized, double-blind crossover─to assess whether reducing short-term indoor particle concentrations results in improved test scores in college students in Tianjin, China. Participants (n= 162) were randomly assigned to one of two similar classrooms and completed a standardized English test on two consecutive weekends. Air purifiers with active or sham (i.e., filter removed) particle filtration were placed in each classroom. The filtration mode was switched between the two test days. Linear mixed-effect models were used to evaluate the effect of the intervention mode on the test scores. The results show that air purification (i.e., reducing PM) was significantly associated with increases in the zscore for combined (0.11 [95%CI: 0.02, 0.21]) and reading (0.11 [95%CI: 0.00, 0.22]) components. In conclusion, a short-term reduction in indoor particle concentration led to improved test scores in students, suggesting an improvement in cognitive function.

To investigate the combined impacts of anthropogenic and biogenic emissions on the formation of secondary organic aerosols (SOA), SOA molecular tracers, their corresponding volatile organic compound precursors, and other air pollutants were measured online during the winter and summer seasons of 2022 in an industrial city, Zibo, China. The results indicate that the average concentrations of SOA tracers were 16.1 ± 9.8 ng m−3in winter and 99.4 ± 57.2 ng m−3in summer. During winter, anthropogenic SOA (ASOA, the sum of SOA derived from naphthalene and mono‐aromatic volatile organic compounds) dominated, whereas isoprene SOA (SOAI) prevailed in summer. Correlation analysis between SO42−and both SOAIand high‐order monoterpene SOA tracers (SOAM‐H) (R= 0.46–0.72, p< 0.001) revealed that higher aerosol acidity facilitated the formation of SOAIand SOAM‐H, with SO2emissions playing a significant role in leading to higher acidity. Most biogenic SOA (BSOA) tracers exhibited a significant positive correlation with NO3−, particularly in winter, implying the remarkable influence of NOxemissions on BSOA formation. The levels of BSOA tracers increased with NH3, indicating that NH3can enhance the formation of BSOA. In summer, SOA formation correlated with Ox(Ox= O3+ NO2), indicating the substantial impact of atmospheric oxidizing capacity on SOA formation. During winter, aerosol liquid water content (ALWC) correlated well with SOAItracers (i.e., 3‐hydroxyglutaric acid (3‐HGA) and 3‐hydroxy‐4,4‐dimethylglutaric acid (3‐HDMGA)), and 2,3‐dihydroxy‐4‐oxopentanoic acid (DHOPA) (R> 0.5, p< 0.001), indicating the important contribution of aqueous‐phase formation of SOA. These findings underscore the significant role of anthropogenic pollutant emissions in the formation of ASOA and BSOA in urban environments. Air pollution and climate change are influenced by secondary organic aerosol (SOA), which are formed through a series of chemical reactions that could involve both anthropogenic and natural emissions. However, there is limited research on the relationship between the precursors of SOA and the resulting SOA at the molecular level. To address this gap, we investigated the influence of anthropogenic emissions on the formation of SOA in a typical industrial city (Zibo, China) based on online measurements of SOA molecular tracers and corresponding volatile organic compound precursors, and other air pollutants, at a high‐time resolution during the winter and summer of 2022. Our findings demonstrate the important role of human‐generated pollutants in the formation of anthropogenic SOA and biogenic SOA. These results enhance our understanding of SOA formation in industrial cities and provide valuable insights for the formulation of SOA management and control strategies in such areas. Anthropogenic secondary organic tracers were the predominant contributors during winter, whereas isoprene secondary organic aerosols (SOA) tracers were predominant during summerAnthropogenic pollutants have an important impact on the formation of SOAHigh correlation was observed between SOA tracers and Oxin summer and aerosol liquid water content in winter Anthropogenic secondary organic tracers were the predominant contributors during winter, whereas isoprene secondary organic aerosols (SOA) tracers were predominant during summer Anthropogenic pollutants have an important impact on the formation of SOA High correlation was observed between SOA tracers and Oxin summer and aerosol liquid water content in winter

Amines are considered as an emerging class of atmospheric pollutants that are of great importance to atmospheric chemistry and new particle formation. As a typical amine, 2-amino-2-methyl-1-propanol (AMP) is one of the proposed solvents for capturing CO2from flue gas streams in amine-based post-combustion CO2capture plants, and it is expected to result in AMP emission and secondary product formation in the atmosphere. However, the current knowledge of its atmospheric chemistry and kinetics is poorly understood, particularly in a reactive environment. In this work, we used the CSIRO smog chamber to study the photo-oxidation of AMP in the presence of volatile organic compound (VOC)–NOx surrogate mixtures over a range of initial amine concentrations. O3formation was significantly inhibited when AMP was added to the surrogate VOC–NOx mixtures, implying that AMP could alter known atmospheric chemical reaction pathways and the prevailing reactivity. Simultaneously, a large amount of AMP-derived secondary aerosol was formed, with a considerably high aerosol mass yield (i.e., ratio of aerosol formed to reacted AMP) of 1.06 ± 0.20. Based on updated knowledge of its kinetics, oxidation pathways, and product yields, we have developed a new mechanism (designated as CSIAMP-19), integrated it into the Carbon Bond 6 (CB6) chemical mechanism, and evaluated it against available smog chamber data. Compared with the existing AMP mechanism (designated as CarterAMP-08), the modified CB6 with CSIAMP-19 mechanism improves prediction against AMP–VOC–NOx experiments across a range of initial AMP concentrations, within ±10% model error for gross ozone production. Our results contribute to scientific understanding of AMP photochemistry and to the development of the chemical mechanism of other amines. Once some potential limitations are considered, the updated AMP reaction scheme can be further embedded into the chemical transport model for regional modeling scenarios where AMP-related emissions are of concern.

To study the vertical distributions of PM2.5mass and chemical components over the Yangtze River area, PM2.5was sampled with filters over Changzhou, which is located in the eastern part of China, Shashi, which is located in the central part of China, and Xinjin, which is located in the western part of China, on the Yun-12 aircraft from August 21 to September 13, 2003. The samples were weighed for mass concentrations, and the chemical profiles of 8 inorganic ions (Cl−, NO3−, SO42−, Na+, NH4+, K+, Mg2+and Ca2+), carbon fractions (organic carbon and elemental carbon) and 18 elements were analyzed in a laboratory. The mass concentrations at 400–1500 m were greater than those at 1600–3200 m, indicating the effect of ground surface sources. Similar PM2.5compositions were found both at 400–1500 and 1600–3200 m. SO42−was the dominant ionic component, followed by NO3−, NH4+, Ca2+, K+, Na+, Cl−and Mg2+. Secondary inorganic ions (SO42−, NO3−and NH4+) contributed to 80–83% of the total ionic species, indicating that the role of secondary formation plays an important role in water-soluble ions. SO42−mainly existed as (NH4)2SO4.NH4+was unable to completely neutralize SO42−and NO3−, and the deficit was approximately 32%. More than 70% of the Ca2+contribution was derived from anthropogenic sources, which was related to construction activities and cement manufacturing. K+was predominantly derived from anthropogenic sources (72.2–74.0%) and crustal sources (approximately, 23.3–24.9%). The OC/EC ratios at 1600–2800 m were greater than those at 500–1200 m, which was probably due to the presence of secondary products that were produced by photochemical smog activities during the uplifting of air masses.

Background: Carbamazepine (CBZ) has complex pharmacokinetic properties leading to fluctuation in plasma level, which requires routine therapeutic drug monitoring (TDM) to ensure its efficacy and prevent adverse effects. The objective of this study is directed towards developing and validating a simple, precise, rapid and highly sensitive liquid chromatography-mass spectrometry (LC/MS) technique for measuring CBZ concentration in human plasma of epileptic patients in routine TDM. Methods: The blood samples of 103 epileptic patients were collected for therapeutic monitoring of CBZ with validated LC/MS assay. The analytes from plasma were extracted with methanol by simple protein precipitation method. The Agilent 1100 LC/MS system was used. The ammonium acetate 5mM: methanol (40: 60 v/v) and diamonsil C18 (150mm.6mm, 5μm) were used as mobile phase and analytical column for the separation of analyte, respectively. The temperature of column was 25°C and the rate of flow was set at 0.8 mL/minute. International Conference on Harmonisation (ICH) guidelines were used for the validation of the method. Results: The stated LC/MS assay displayed good linearity in the range of 5-1000ng/ml and linearity equation of calibration curve was y= 2.44516x +0.00348175 with a correlation coefficient (R2) of 0.99881. The lower limit of quantitation (LLOQ) of the stated technique was observed at concentration of 5ng/ml. The linearity, recovery, accuracy and precision, specificity and stability results were within the acceptance limits of ICH guidelines. Conclusion: The simple, precise, rapid and highly sensitive LC/MS technique was developed and validated and successfully applied in TDM of 103 epileptic patients who were using CBZ. Besides TDM, the stated method can also be applied in bioequivalence, pharmacokinetics and pharmacovigilance studies.

Background: Carbamazepine (CBZ) has a narrow therapeutic index that urges therapeutic drug monitoring (TDM) to ensure its efficacy and prevent toxicity. Several accurate and sensitive chromatography methods are available for TDM of CBZ but are not used routinely due to expensive instrumentation, time consuming and complicated procedures. Enzyme-multiplied immunoassay technique (EMIT) is used in routine TDM of CBZ due to simple, rapid and easy use. The aim of this study is to evaluate the correlation between Liquid chromatography-mass spectrometry (LC/MS) assay and routinely used EMIT assay for TDM of CBZ concentration in human plasma and to offer a guide for clinical and pathological laboratories in clinical settings. Methods: The blood samples of 103 epileptic patients using CBZ were collected for TDM. The TDM was performed by two different types of assay methods i.e. LC/MS and EMIT. The correlation between two different assays was evaluated in 93 patients with statistical analysis of Bland-Altman plot and deming regression analysis in MedCalc software and statistical package for the social sciences (SPSS), respectively. Results: The TDM results of CBZ obtained by LC/MS and EMIT assays were evaluated for correlation in 93 epileptic patients because the results of 10 patients were below the lower limit of quantification (LLOQ) of EMIT. The correlation between two methods was good (R2= 0.971) but carbamazepine plasma concentrations determined by EMIT were slightly higher than LC/MS. The 95% confidence interval was 0.94~2.74 µg/mL. The coefficient of variation (CV) of intra and inter-day were below 3% in LC/MS method. The calibration curves exhibited decent linearity in the 5.0-1000 ng/mL concentration range for LC/MS and 2-20 µg/mL for EMIT. The LLOQ of LC/MS and EMIT was 5 ng/mL and 2 µg/mL, respectively, which suggested that LLOQ of LC/MS is 400 times lower than EMIT. Conclusion: The correlation between results of LC/MS and EMIT assays for TDM of CBZ in 93 epileptic patients was evaluated. There was a slight difference between these two methods with EMIT providing slightly higher concentration levels of CBZ than concentrations levels provided by LC/MS, but further evaluation is needed. The results of LC/MS method are more precise and acceptable. However, a good correlation still exists between the two methods. EMIT is faster, cheaper and requires less time and can be used as alternative choice in TDM of CBZ.

Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO2, CO, CH4, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC-FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO2. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO2, CO, CH4, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC-FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO2. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.

Systemic inflammation is a key mechanism in the development of cardiovascular diseases induced by exposure to fine particles (particles with aerodynamic diameter ≤2.5 μm [PM2.5]). However, little is known about the effects of chemical constituents of PM2.5on systemic inflammation. In this cross-sectional study, filter samples of personal exposure to PM2.5were collected from community-dwelling older adults in Tianjin, China, and the chemical constituents of PM2.5were analyzed. Blood samples were collected immediately after the PM2.5sample collection. Seventeen cytokines were measured as targets. A linear regression model was applied to estimate the relative effects of PM2.5and its chemical constituents on the measured cytokines. A positive matrix factorization model was employed to distinguish the sources of PM2.5. The calculated source contributions were used to estimate their effects on cytokines. After adjusting for other covariates, higher PM2.5-bound copper was significantly associated with increased levels of interleukin (IL)1β, IL6, IL10, and IL17 levels. Source analysis showed that an increase in PM2.5concentration that originated from tire/brake wear and cooking emissions was significantly associated with enhanced levels of IL1β, IL6, tumor necrosis factor alpha (TNFα), and IL17. In summary, personal exposure to some PM2.5constituents and specific sources could increase systemic inflammation in older adults. These findings may explain the cardiopulmonary effects of specific particulate chemical constituents of urban air pollution.

Atmospheric particulate matter (PM) imposes uncertain impacts on both radiative forcing and human health. Ambient PM has been comprehensively studied in China's megacities, while its compositions, sources, and characterizations in the Qinghai‐Tibet Plateau (QTP) are not fully understood. An autumn observation campaign was conducted during 1–14 October 2013 at a national background monitoring station (3,295 m above sea level, a.s.l.) in the QTP. Real time concentrations of inorganic water‐soluble ions (WSIs) associated with PM2.5(PM with aerodynamic diameter equal to or less than 2.5 μm) were measured in addition to PM2.5concentrations, gaseous pollutants, and meteorological parameters. SO42−was the most abundant WSI (10.0 μg/m3) followed by NH4+(2.0 μg/m3), and NO3−(1.7 μg/m3). Observed WSI concentrations were higher as compared to other QTP monitoring sites and some remote sites. The levels of SO42−were comparable to concentrations of some urban sites. The correlation analysis disclosed the relationship among WSIs and other gaseous pollutants and discussed the possibilities of biomass burning as the potential sources. Extended aerosol inorganic model (E‐AIM) model results revealed that particulate sulfate, nitrate, and ammonium (SNA) existed in both liquid and solid phases. High sulfate and nitrate oxidation ratios indicated strong secondary formation of both SO42−and NO3−. By analyzing the relationship among SOR/NOR, RH, and O3, we found that both photochemical and heterogeneous reactions contributed to the formation of SO42−, while the conversion of NO2to NO3−was likely to occur via photochemical reactions in the presence of high O3concentrations and strong sunlight. We studied characters of WSIs associated with PM2.5 at a background site on the QTPWe analyzed formation pathway of particulate SO42−and NO3−at the background siteHourly levels of WSIs were measured to understand their variations on the QTP