Impact of PM2.5 exposure on mortality and tumor recurrence in resectable non-small cell lung carcinoma

This study aimed to explore the impact of PM 2.5 exposure on survival, post-operative outcomes, and tumor recurrence in resectable non-small cell lung cancer (NSCLC) patients. The study cohort comprised 587 patients at Chiang Mai University Hospital between January 1, 2010, and December 31, 2017. Patients were categorized based on their residents' average PM 2.5 concentration into two groups: exposed (PM 2.5 ≥ 25 µg/m3 annual mean) and unexposed (PM 2.5 < 25 µg/m3 annual mean). The exposed group had 278 patients, while the unexposed group had 309 patients. Baseline differences in gender and surgical approach were observed between the groups. Multivariable regression analysis revealed that patients in the exposed group had a higher risk of death (HR 1.44, 95% CI, 1.08-1.89, p = 0.012). However, no significant associations were found between PM 2.5 and post-operative pulmonary complications (RR 1.12, 95% CI, 0.60-2.11, p = 0.718), in-hospital mortality (RR 1.98, 95% CI, 0.40-9.77, p = 0.401), and tumor recurrence (HR 1.12, 95% CI, 0.82-1.51, p = 0.483). In conclusion, a PM 2.5 concentration ≥ 25 µg/m3 annual mean was associated with decreased overall survival and a potential increase in in-hospital mortality among resectable NSCLC patients. Larger studies with extended follow-up periods are required to validate these findings.

Alterations in the Blood Kynurenine Pathway Following Long-Term PM2.5 and PM10 Exposure: A Cross-Sectional Study

Human exposure to PM2.5 and PM10 has been linked to respiratory and cardiovascular diseases through inflammation activation. The kynurenine pathway is associated with inflammation, and it is necessary to investigate the effects of long-term PM2.5 and PM10 exposure on this pathway. This study aimed to conduct a cross-sectional analysis of long-term PM2.5 and PM10 exposure's impact on the kynurenine pathway using proton NMR spectroscopy (1H-NMR). The participants were divided into a low-PM-exposure group (LG; n = 98), and a high-PM-exposure group (HG; n = 92). The metabolites of tryptophan were determined in blood by 1H-NMR. Serotonin, cinnabarinic acid, xanthurenic acid, 5-hydroxytryptophan, indoleacetic acid, tryptamine, melatonin, L-tryptophan, 5-hydroxy-L-tryptophol, indoxyl, 2-aminobenzoic acid, 5-HTOL, hydroxykynurenine, L-3-hydroxykynurenine, N-formyl kynurenine, 3-hydroxy anthranilic acid, kynurenic acid, and picolinic acid significantly increased (p < 0.05) in the HG group. Conversely, NAD and quinolinic acid significantly decreased in the HG group compared to the LG group. The enzyme activities of indoleamine 2,3-dioxygenase and formamidase significantly decreased, while kynureninase and kynurenine monooxygenase significantly increased. The kynurenine pathway is linked to inflammation and non-communicable diseases. Disruption of the kynurenine pathway from particulate matter might promote diseases. Reducing exposure to the particulate matter is crucial for preventing adverse health effects.

Impact of Air Pollution and Allergic Status on Health-Related Quality of Life among University Students in Northern Thailand

BACKGROUND

Global awareness of ambient air pollution has heightened due to its detrimental impact on health, particularly in regions with elevated PM2.5 levels. Chiang Mai has emerged as an area experiencing the highest PM2.5 levels in Thailand.

OBJECTIVES

to examine the prevalence of respiratory allergies and assess the impact of air pollution on the health-related quality of life (QoL) among university students in Chiang Mai.

METHODS

Chiang Mai University (CMU) and Maejo University (MJU) students were recruited. The Global Asthma Network (GAN) questionnaire screened for respiratory allergies (RAs). The disease-specific QoL questionnaire (Rcq-36) was administered twice during low-PM2.5 and high-PM2.5 seasons to evaluate air pollution's impact on health-related QoL. Those showing potential RAs underwent a skin prick test (SPT) to investigate allergic sensitization.

RESULTS

Out of 406 participants, 131 (32%) reported respiratory allergies. Among those undergoing SPT, a high rate (82.54%) had positive results. Across both universities, students reported significantly lower QoL in multiple domains, particularly respiratory, eye, sleep, and emotional well-being, during the high-PM2.5 season. This aligned with their poorer self-reported health on a visual analog scale (VAS; p-value < 0.01). PM2.5 levels significantly impacted social functioning for CMU students (p-value = 0.001) and role limitations for MJU students (p-value < 0.001). Notably, participants without respiratory allergies (non-RAs) were more significantly affected by PM2.5 than RA participants in almost all parameters, despite experiencing fewer baseline symptoms.

CONCLUSIONS

Respiratory allergies, particularly allergic rhinitis, are prevalent among university students in Chiang Mai. This study underscores the substantial negative impact of ambient air pollution on QoL for both allergic and non-allergic students.

Source appointment and health risk assessment of polycyclic aromatic hydrocarbons in paddy grain from Thailand and Laos

Rice is a staple meal for the majority of Asians. However, human exposure to polycyclic aromatic hydrocarbons from paddy grain is largely unknown in Thailand and Laos. Therefore, information on the quantitative measurement and assessment of the health problems caused by PAHs was analyzed. The results showed that the concentrations of total PAHs in paddy grain in Thailand and Laos were 38.86 ± 5.13 and 11.35 ± 1.96 ng g^-1, respectively. The highest concentration of PAHs in Thailand was B[k]F, whereas D[a,h]A was found to be the highest in Laos. A p-value less than 0.05 was defined, which showed B[b]F and B[k]F from Thailand and Laos were significant, which indicated that they could be from a different pollutant source. The main finding of this study, which was supported by the diagnostic ratios of PAHs and HCA, was that the primary source of PAHs was assumed to be incomplete combustion of petroleum products, which was caused by the burning of industrial fuels or vehicle exhausts, as well as open burning. The findings suggest that these two nations have similar PAH origins. Agricultural waste burning and transportation emissions are well-known sources of PAHs in Thailand and Laos. The cancer risk assessment method was based on the accumulation of PAHs from paddy grains. An ILCR of 1.0E-06 to 1.0E-04 was considered a tolerable limit of cancer risk, while a risk > 1.0E-04 was considered a concern in terms of cancer risk. The findings indicated that while PAH emissions exist, their contribution to global toxicity may be anticipated to be low in inhalation exposure. The higher values of ingestion and dermal risk estimated were regarded as the tolerable limit of cancer risk in children and adults from both countries, indicating that cancer risk in both nations falls within the "acceptable level" range.

Air Pollution-Related Respiratory Diseases and Associated Environmental Factors in Chiang Mai, Thailand, in 2011-2020

The unfavorable effects of global climate change, which are mostly the result of human activities, have had a particularly negative effect on human health and the planet's ecosystems. This study attempted to determine the seasonality and association of air pollution, in addition to climate conditions, with two respiratory infections, influenza and pneumonia, in Chiang Mai, Thailand, which has been considered the most polluted city on Earth during the hot season. We used a seasonal-trend decomposition procedure based on loess regression (STL) and a seasonal cycle subseries (SCS) plot to determine the seasonality of the two diseases. In addition, multivariable negative binomial regression (NBR) models were used to assess the association between the diseases and environmental variables (temperature, precipitation, relative humidity, PM2.5, and PM10). The data revealed that influenza had a clear seasonal pattern during the cold months of January and February, whereas the incidence of pneumonia showed a weak seasonal pattern. In terms of forecasting, the preceding month's PM2.5 and temperature (lag1) had a significant association with influenza incidence, while the previous month's temperature and relative humidity influenced pneumonia. Using air pollutants as an indication of respiratory disease, our models indicated that PM2.5 lag1 was correlated with the incidence of influenza, but not pneumonia. However, there was a linear association between PM10 and both diseases. This research will help in allocating clinical and public health resources in response to potential environmental changes and forecasting the future dynamics of influenza and pneumonia in the region due to air pollution.

Concentrations and source identification of priority polycyclic aromatic hydrocarbons in sediment cores from south and northeast Thailand

In this study, the environmental fate of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in tropical lake sediments and their potential sources have been discussed. 15 PAHs (i.e. ΣPAH) have been investigated in two lakes, namely Songkhla Lake (SKL) and Nong Han Kumphawapi Lake (NHL), which are located at the southern and north-eastern parts of Thailand, respectively. Since these two lakes are registered as important wetlands under the Ramsar convention (United Nations Educational, Scientific and Cultural Organization: UNESCO), the quantitative identification of potential contributors of PAHs is an inevitable analytical tool for launching an evidence-based policy. The ΣPAH concentrations observed in SKL and NHL sediments (n = 135) were in the range of 19.4–1,218 ng g⁻¹ and 94.5–1,112 ng g⁻¹, respectively. While the exponential decline of ΣPAH contents were detected in SKL sediments, NHL showed a trend of enhancing PAH contents with depth. The averaged benzo [a]pyrene (B [a]P) contents of surface sediments in both lakes were much below the value stipulated by the United States Environmental Protection Agency (US-EPA) guidelines for carcinogen risk assessment. Based on numerous multivariate statistical techniques coupled with source apportionment analysis, “biomass burning” and “anthropogenic activities” are two potential contributors of the PAHs detected in the study areas. To achieve the long-term conservation of nature with related ecosystem services and cultural values, it is therefore important to promote decision-making based on ecotoxicological studies of carcinogenic substances.

A scoping review on the health effects of smoke haze from vegetation and peatland fires in Southeast Asia: Issues with study approaches and interpretation

Smoke haze due to vegetation and peatland fires in Southeast Asia is a serious public health concern. Several approaches have been applied in previous studies; however, the concepts and interpretations of these approaches are poorly understood. In this scoping review, we addressed issues related to the application of epidemiology (EPI), health burden estimation (HBE), and health risk assessment (HRA) approaches, and discussed the interpretation of findings, and current research gaps. Most studies reported an air quality index exceeding the 'unhealthy' level, especially during smoke haze periods. Although smoke haze is a regional issue in Southeast Asia, studies on its related health effects have only been reported from several countries in the region. Each approach revealed increased health effects in a distinct manner: EPI studies reported excess mortality and morbidity during smoke haze compared to non-smoke haze periods; HBE studies estimated approximately 100,000 deaths attributable to smoke haze in the entire Southeast Asia considering all-cause mortality and all age groups, which ranged from 1,064-260,000 for specified mortality cause, age group, study area, and study period; HRA studies quantified potential lifetime cancer and non-cancer risks due to exposure to smoke-related chemicals. Currently, there is a lack of interconnection between these three approaches. The EPI approach requires extensive effort to investigate lifetime health effects, whereas the HRA approach needs to clarify the assumptions in exposure assessments to estimate lifetime health risks. The HBE approach allows the presentation of health impact in different scenarios, however, the risk functions used are derived from EPI studies from other regions. Two recent studies applied a combination of the EPI and HBE approaches to address uncertainty issues due to the selection of risk functions. In conclusion, all approaches revealed potential health risks due to smoke haze. Nonetheless, future studies should consider comparable exposure assessments to allow the integration of the three approaches.

An Application of Artificial Neural Network to Evaluate the Influence of Weather Conditions on the Variation of PM2.5-Bound Carbonaceous Compositions and Water-Soluble Ionic Species

Previous studies have determined biomass burning as a major source of air pollutants in the ambient air in Thailand. To analyse the impacts of meteorological parameters on the variation of carbonaceous aerosols and water-soluble ionic species (WSIS), numerous statistical models, including a source apportionment analysis with the assistance of principal component analysis (PCA), hierarchical cluster analysis (HCA), and artificial neural networks (ANNs), were employed in this study. A total of 191 sets of PM2.5 samples were collected from the three monitoring stations in Chiang-Mai, Bangkok, and Phuket from July 2020 to June 2021. Hotspot numbers and other meteorological parameters were obtained using NOAA-20 weather satellites coupled with the Global Land Data Assimilation System. Although PCA revealed that crop residue burning and wildfires are the two main sources of PM2.5, ANNs highlighted the importance of wet deposition as the main depletion mechanism of particulate WSIS and carbonaceous aerosols. Additionally, Mg2+ and Ca2+ were deeply connected with albedo, plausibly owing to their strong hygroscopicity as the CCNs responsible for cloud formation.

Investigating the seasonal variability in source contribution to PM2.5 and PM10 using different receptor models during 2013-2016 in Delhi, India

The present work deals with the seasonal variations in the contribution of sources to PM_2.5 and PM₁₀ in Delhi, India. Samples of PM_2.5 and PM₁₀ were collected from January 2013 to December 2016 at an urban site of Delhi, India, and analyzed to evaluate their chemical components [organic carbon (OC), elemental carbon (EC), water-soluble inorganic components (WSICs), and major and trace elements]. The average concentrations of PM_2.5 and PM₁₀ were 131 ± 79 μg m^-3 and 238 ± 106 μg m^-3, respectively during the entire sampling period. The analyzed and seasonally segregated data sets of both PM_2.5 and PM₁₀ were used as input in the three different receptor models, i.e., principal component analysis-absolute principal component score (PCA-APCS), UNMIX, and positive matrix factorization (PMF), to achieve conjointly corroborated results. The present study deals with the implementation and comparison of results of three different multivariate receptor models (PCA-APCS, UNMIX, and PMF) on the same data sets that allowed a better understanding of the probable sources of PM_2.5 and PM₁₀ as well as the comportment of these sources with respect to different seasons. PCA-APCS, UNMIX, and PMF extracted similar sources but in different contributions to PM_2.5 and PM₁₀. All the three models extracted 7 similar sources while mutually confirmed the 4 major sources over Delhi, i.e., secondary aerosols, vehicular emissions, biomass burning, and soil dust, although the contribution of these sources varies seasonally. PCA-APCS and UNMIX analysis identified a less number of sources (besides mixed type) as compared to the PMF, which may cause erroneous interpretation of seasonal implications on source contribution to the PM mass concentration.

Relationship Between COVID-19-Infected Number and PM2.5 Level in Ambient Air of Bangkok, Thailand

Several empirical studies of reductions in air pollutants as social distancing and working from home (WFH) policies have sparked recommendations that the COVID-19 pandemic might have been responsible for better air quality particularly in urban area. These findings offer a compelling provocation for the scientific community to detect and investigate variations to air quality as a consequence of government enforced quarantine. In spite of countless research studies focusing on the connection between WFH policy and air pollutant levels, the majority of discussion has unfortunately ignored the central role of other potential sources (e.g. agricultural waste burnings, cooking emissions, and industrial releases) in governing air quality, or has neglected the psychological and social impacts of COVID-19. In this study, a t test was used to compare the average concentrations of PM_2.5 and COVID-19-infected numbers (n) in three different periods which were n < 300 vs. n ≧ 300, n < 500 vs. n ≧ 500, and n < 700 vs. n ≧ 700. Some significant differences were observed in the groups of n < 500 vs. n ≧ 500, and n < 700 vs. n ≧ 700 indicating that the psychological and social impacts play a crucial role in restricting daily activities and thus reducing the atmospheric contents of PM_2.5 in some areas. Further assessments were conducted by separating PM_2.5 contents into three different periods (i.e. Period-I: day-1 ~ day-10; Period-II: day-11 ~ day-20; Period-III: day-21 ~ day-31). Some significant reductions of PM_2.5 during the Period-I were detected in the eastern area of Bangkok. In addition, Pearson correlation analysis showed that hot-spot numbers appear to be a minor of importance in controlling PM_2.5 levels in the ambient air of Bangkok, Thailand.

Emission characteristics and temporal variation of PAHs and their derivatives from an ocean-going cargo vessel

Polycyclic aromatic hydrocarbons (PAHs), nitro- (NPAHs) and oxy-derivatives (OPAHs) are of considerable concern due to their toxicity and carcinogenic hazards. Ships are recognized as an important emission source of these compounds. Marine diesel oil (MDO) and heavy fuel oil (HFO) are the two most commonly used fuels. The emission characteristics and toxicities of PM_2.5-bound PAHs, NPAHs and OPAHs due to HFO and MDO combustion in atypical ocean-going vessel were investigated. The EF variability of polycyclic aromatic compounds (PACs) varied considerably with the fuel formulation (HFO and MDO) and engine loading (20%-100%). The concentration of ΣPACs was 0.63 mg/kWh for MDO and ranged from 2.14 to 9.80 mg/kWh for HFO. Compared to HFO-20%, the EFs of ΣPAHs, ΣNPAHs and ΣOPAHs from MDO-20% were reduced by 97%, 77% and 73%, respectively. As identified through the coefficient of divergence, the profile of HFO-20% was notably different from those under the other three engine loadings for HFO. In addition, the emissions of ΣPAHs and ΣOPAHs showed a significant correlation with PM_2.5, while they were relatively weak for ΣNPAHs. However, the CO and PAC emissions were not highly correlated. Furthermore, the BaP_eq-ΣPAHs values were 0.010 mg/g for MDO and ranged from 0.092 mg/g to 0.306 mg/g for HFO, and the reduction ranged from 89% to 97% by substituting MDO for HFO. These data highlight the importance of improving fuel quality in close proximity to port areas and are useful for enhancing relevant databases.

Review on recent progress in observations, source identifications and countermeasures of PM2.5

Recently, PM2.5 (atmospheric fine particulate matter with aerodynamic diameter ≤ 2.5 μm) have received so much attention that the observations, source appointment and countermeasures of it have been widely studied due to its harmful impacts on visibility, mood (mental health), physical health, traffic safety, construction, economy and nature, as well as its complex interaction with climate. A review on the PM2.5 related research is necessary. We start with summary of chemical composition and characteristics of PM2.5 that contains both macro and micro observation results and analysis, wherein the temporal variability of concentrations of PM2.5 and major components in many recent reports is embraced. This is closely followed by an overview of source appointment, including the composition and sources of PM2.5 in different countries in the six inhabitable continents based on the best available results. Besides summarizing PM2.5 pollution countermeasures by policy, planning, technology and ideology, the World Air Day is proposed to be established to inspire and promote the crucial social action in energy-saving and emission-reduction. Some updated knowledge of the important topics (such as formation and evolution mechanisms of hazes, secondary aerosols, aerosol mass spectrometer, organic tracers, radiocarbon, emissions, solutions for air pollution problems, etc.) is also included in the present review by logically synthesizing the studies. In addition, the key research challenges and future directions are put forward. Despite our efforts, our understanding of the recent reported observations, source identifications and countermeasures of PM2.5 is limited, and subsequent efforts both of the authors and readers are needed.

Study on theoretical models of regional humanity lung cancer hazards assessment

PURPOSE

To establish the concept of lung cancer hazard assessment theoretical models, evaluating the degree of lung cancer risk of Beijing for regional population lung cancer hazard assessment to provide a basis for technical support.

MATERIALS AND METHODS

ISO standards were used to classify stratified analysis for the entire population, life cycle, processes and socioeconomic management. Associated risk factors were evaluated as lung cancer hazard risk assessment first class indicators.

STUDY DESIGN

Using the above materials, indicators were given the weight coefficients, building lung cancer risk assessment theoretical models. Regional data for Beijing were entered into the theoretical model to calculate the parameters of each indicator and evaluate the degree of local lung cancer risk.

RESULTS

Adopting the concept of lung cancer hazard assessment and theoretical models for regional populations, we established a lung cancer hazard risk assessment system, including 2 first indicators, 8 secondary indicators and 18 third indicators. All indicators were given weight coefficients and used as information sources. Score of hazard for lung cancer was 84.4 in Beijing.

CONCLUSIONS

Comprehensively and systematically building a lung cancer risk assessment theoretical model for regional populations in conceivable, evaluating the degree of lung cancer risk of Beijing, providing technical support and scientific basis for interventions for prevention.