Chronic Effects of High Fine Particulate Matter Exposure on Lung Cancer in China

Long-term exposure to air pollution and lung cancer incidence: findings from improved exposure assessment and extended population

PURPOSE

Accumulating evidence suggested long-term exposure to air pollution as a risk factor of lung cancer. Recent efforts confirmed the association based on extended population and individual exposure by leveraging administrative databases and complete address information. However, few studies achieved simultaneous improvements. Using the 2 million cohort along with their individual residential exposures, this study aimed to investigate the association of four criteria pollutants and incident lung cancer in the Seoul Metropolitan Area, South Korea.

METHODS

Our study population included 2,035,278 people aged ≥ 30 years and without cancer for 2002-2006 from the National Health Insurance System database. We identified lung cancer incidence for 2007-2016 and assessed individual long-term exposure to particulate matter ≤ 10 µm and 2.5 µm in diameter (PM10 and PM2.5), nitrogen dioxide (NO2), and ozone at participants' home addresses by using previously validated exposure prediction models. Using time-varying Cox proportional hazard models, we estimated hazard ratios (HRs) per interquartile range increase in each pollutant concentration adjusting for individual and area-level characteristics.

RESULTS

There were 18,229 lung cancer new cases over 10 years. We did not find the association for all four pollutants (PM10: HR = 0.99 [95% Confidence Interval = 0.93-1.04]; PM2.5: 0.97 [0.92-1.02]; NO2: 1.00 [0.96-1.05]; and ozone: 1.01 [0.98-1.04]). The extended stratified and sensitivity analyses mostly showed null associations.

CONCLUSION

Our findings of no association contradictory to existing evidence, despite the considerable improvement in exposure assessment and population size, suggest further examination by integrating histological variation and indoor and/or personal exposure.

Associations between long-term exposure to particulate matter and mortality from multiple causes among the oldest-old people

Older people are considered more vulnerable to particulate matter (PM) exposure in terms of mortality risk. However, little is known about the associations among the oldest-old people in the era of rapid ageing. Thus, the objective of this study was to estimate the associations between long-term exposure to PM and the risk of mortality from multiple causes among the oldest-old people (aged over 80). In total, all-cause mortality and mortality from eight broad and 23 specific causes were estimated on the basis of 7-year cohort data for almost 10 thousand oldest-old people in China. Moreover, time-dependent characteristics of the associations were determined. PM exposure was associated with increased mortality risks for a wide range of causes, including neoplasms and nervous system diseases, which have rarely been assessed before. With respect to specific causes, pulmonary heart diseases and diseases of pulmonary circulation was more affected by PM exposure. Notably, the impacts on some diseases, such as the circulatory system and hypertensive diseases, decreased during the COVID-19 pandemic. The effect may be modified by some social factors during the pandemic. Understanding the dynamic associations between PM exposure and mortality from multiple causes is highly important for identifying sensitive cause-specific deaths.

Fine particulate matter exposure and cancer risk: a systematic review and meta-analysis of prospective cohort studies

Studies examining the relationship between fine particulate matter (PM2.5) exposure and cancer risk is inconclusive, with an evident scarcity of comprehensive data on the overall cancer risk. Given the emergence of new evidence, updated meta-analyses is essential. A search was performed on multiple databases including PubMed, Embase, Scopus, Web of Science, and the Cochrane Library up to Jan 2025. Hazard ratios (HRs), relative risks (RRs), or incidence rate ratios (IRRs) with their 95 % confidence intervals (CIs) were extracted and pooled. Moreover, a comprehensive and detailed quality assessment of the included studies was conducted to validate the plausibility of the findings. Overall, 57 original studies were included, covering 36 cancer categories and including overall cancer and malignancies specific to particular anatomical sites. For each increase of 10 μg per cubic meter in PM2.5 concentration, there was an observed pooled HR of 1.07 for overall cancer (95 %CI:1.02-1.13). In the case of site-specific cancers, the pooled HRs were 1.11 (95 %CI:1.07-1.15), 1.06 (95 %CI:1.02-1.11), 1.17 (95 %CI:1.07-1.28), and 1.14 (95 %CI:1.03-1.26) for lung, breast, liver and esophageal cancers, respectively. Furthermore, PM2.5 exposure may potentially correlate with the risk of cancers at other anatomical locations including upper aerodigestive tract, oral cavity, kidney, skin, as well as digestive organs. In light of available evidence, it is inferred that PM2.5 exposure could potentially raise overall cancer risk with moderate certainty. As for site-specific malignancies, there is very low certainty evidence for lung cancer, low certainty evidence for breast cancer, and moderate certainty evidence for both liver and esophageal cancers.

Effect of Long-Term Fine Particulate Matter Exposure on Lung Cancer Incidence and Mortality in Chinese Nonsmokers

Rationale: The association between fine particulate matter (particulate matter ⩽2.5 μm in aerodynamic diameter, PM2.5) and lung cancer incidence in nonsmokers (LCINS) remains inconsistent. Objectives: To investigate the association between long-term PM2.5 exposure and LCINS in a Chinese population and to assess the modifying effect of genetic factors. Methods: Time-dependent Cox proportional hazard models were used to evaluate the hazard ratios (HRs) and 95% confidence intervals (CIs) of PM2.5 with LCINS risk and LCINS-related mortality. The polygenic risk score was constructed to further explore the interactions between genetic risk and PM2.5 exposure. In addition, the population attributable fraction of PM2.5 to lung cancer risk and mortality was calculated. Measurements and Main Results: The results demonstrated significant associations between PM2.5 exposure and LCINS incidence (HR, 1.10 per 10 μg/m3; 95% CI, 1.04-1.17 per 10 μg/m3) and mortality (HR, 1.17 per 10 μg/m3; 95% CI, 1.08-1.27 per 10 μg/m3). Compared with the lowest-risk group, individuals exposed to the high PM2.5 concentration (⩾50.9 μg/m3) and high genetic risk (top 30%) exhibited the highest LCINS incidence (HR, 2.01; 95% CI, 1.39-2.87) and mortality (HR, 2.30; 95% CI, 1.38-3.82). A significant additive interaction between PM2.5 and genetic risk on LCINS incidence was observed. Approximately 33.6% of LCINS cases and 48.5% of LCINS-related deaths in China could be prevented if PM2.5 concentrations were reduced to meet World Health Organization guidelines. Conclusions: Long-term exposure to outdoor PM2.5 increases LCINS risk and LCINS-related mortality, especially in populations with high genetic risk. Strengthening air pollution control measures in China has the potential to significantly reduce the burden of LCINS.

An analysis of the burden of respiratory tract cancers in global, China, the United States and India: findings based on the GBD 2021 database

OBJECTIVE

This study aimed to assess the burden of respiratory tract cancers in China, the United States, India, and worldwide from 1990 to 2021. Also, forecast the evolution of respiratory tract cancers deaths and DALYs burden during 2022 to 2050.

STUDY DESIGN

An epidemiological analysis.

METHODS

Based on the GBD 2021 data, this article analyzed and discussed the trends in burden of respiratory tract cancers in China, the United States, India, and the world from 1990 to 2021. Additionally, the Bayesian Age-Period-Cohort (BAPC) model was used to forecast the evolution of respiratory tract cancers deaths and DALYs burden during 2022 to 2050.

RESULTS

The ASR-Deaths and ASR-DALYs for laryngeal and TBL cancers decreased globally. The burden of disease for TBL cancer increased in China and India (AAPC: 0.38 and 0.69), especially among Chinese women, while laryngeal cancer declined in India (AAPC: -0.69). In contrast, the burden of disease for both cancers declined substantially in the United States (-1.82 AAPC for laryngeal cancer and - 1.74 AAPC for TBL). A notable gender disparity existed in the burden of respiratory tumors, with males experienced a higher disease burden compared to females. In terms of age, the peak incidence of respiratory tract cancers predominantly occurred among individuals aged 65-74, indicating a clear tendency towards a higher prevalence among this age group. Population growth and ageing were primary factors influencing the mortality burden of larynx cancer, whereas epidemiological shifts in TBL cancer markedly impacted DALYs. The forecasted results for ASR-Deaths and ASR-DALYs worldwide from 2022 to 2050 indicated a decline in the burden of both larynx and TBL cancers. However, the deaths and DALYs of TBL cancer in China will show an upward trend, especially for females.

CONCLUSIONS

The disease burden of respiratory tract cancers is a global health issue that needs attention, and situations vary from country to country, requiring personalized measures. Global strategies must address aging populations and socioeconomic disparities to reduce inequities in high-burden regions.

Integrated analysis of air quality-vegetation-health effects of near-future air pollution control strategies

To explore the effects of air pollution control strategies on air quality, vegetation, and health, we conducted an integrated modeling analysis for a representative industrial city, Zibo in the North China Plain, China. Two air pollution control scenarios for the near future (year 2026) are developed, including basic and strict control scenarios. The integrated modeling system based on Weather Research and Forecasting-Community Multiscale Air Quality Modeling (WRF-CMAQ) is utilized to analyze the effects of different scenarios on air quality improvement, vegetation, and health effects. Results indicate that under the basic (strict) control scenarios, the emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter (PM2.5), volatile organic compounds (VOCs), ammonia (NH3) will be reduced by 16% (53%), 14% (24%), 16% (38%), 9% (28%), and 12% (12%) respectively, together with a 15% reduction in emissions of NOx, SO2, VOCs, PM2.5, along with a 5% reduction in NH3 emissions in the vicinity of Zibo in the year 2026, could meet the air quality target for 2026 (with PM2.5 and MDA8 O3_90% at 38 and 185 μg/m³, respectively). In terms of crop yield, under the basic (strict) control scenarios, the ozone-induced yield loss for wheat and corn is expected to increase by 30,000 tonnes (decrease by 80,000 tonnes) and 6000 tonnes (decrease by 4000 tonnes), respectively. In the basic control scenario, the number of deaths due to changes in PM2.5 is 1210 (95% Cl: 950, 1472) and the number of deaths due to O3-related changes is 1042 (95% Cl: 780, 1304). In the strict control scenario, the number of deaths due to PM2.5 changes was 1180 (95% Cl: 992, 1366) and the number of deaths due to O3-related changes was 768 (95% Cl: 581, 955). Our results provide a scientific basis for governments to formulate future air pollution prevention strategies.

Exposure to Air Pollutants and Myocardial Infarction Incidence: A UK Biobank Study Exploring Gene-Environment Interaction

BACKGROUND

Unraveling gene-environment interaction can provide a novel insight into early disease prevention. Nevertheless, current understanding of the interplay between genetic predisposition and air pollution in relation to myocardial infarction (MI) risk remains limited. Furthermore, the potential long-term influence of air pollutants on MI incidence risk warrants more conclusive evidence in a community population.

OBJECTIVE

We investigated interactions between genetic predisposition and exposure to air pollutants on MI incidence.

METHODS

This study incorporated a sample of 456,354 UK Biobank participants and annual mean air pollution (PM 2.5 , PM 10 , NO 2 , and NO x ) from the UK Department for Environment, Food and Rural Affairs (2006-2021). The Cox proportional hazards model was employed to explore MI incidence after chronic air pollutants exposure. By quantifying genetic risk through the calculation of polygenic risk score (PRS), this study further examined the interactions between genetic risk and exposure to air pollutants in the development of MI on both additive and multiplicative scales.

RESULTS

Among 456,354 participants, 9,114 incident MI events were observed during a median follow-up of 12.08 y. Chronic exposure to air pollutants was linked with an increased risk of MI occurrence. Specifically, the hazard ratios (per interquartile range) were 1.12 (95% CI: 1.10, 1.13) for PM 2.5 , 1.20 (95% CI: 1.19, 1.22) for PM 10 , 1.13 (95% CI: 1.12, 1.15) for NO 2 , and 1.12 (95% CI: 1.11, 1.13) for NO x . In terms of the joint effects, participants with high PRS and high level of air pollution exposure exhibited the greatest risk of MI among all study participants (∼ 255 % to 324%). Remarkably, both multiplicative and additive interactions were detected in the ambient air pollutants exposure and genetic risk on the incidence of MI.

DISCUSSION

There were interactions between exposure to ambient air pollutants and genetic susceptibility on the risk of MI onset. Moreover, the joint effects of these two exposures were greater than the effect of each factor alone. https://doi.org/10.1289/EHP14291.

The effects of fine particulate matter on the blood-testis barrier and its potential mechanisms

With the rapid expansion of industrial scale, an increasing number of fine particulate matter (PM2.5) has bringing health concerns. Although exposure to PM2.5 has been clearly associated with male reproductive toxicity, the exact mechanisms are still unclear. Recent studies demonstrated that exposure to PM2.5 can disturb spermatogenesis through destroying the blood-testis barrier (BTB), consisting of different junction types, containing tight junctions (TJs), gap junctions (GJs), ectoplasmic specialization (ES) and desmosomes. The BTB is one of the tightest blood-tissue barriers among mammals, which isolating germ cells from hazardous substances and immune cell infiltration during spermatogenesis. Therefore, once the BTB is destroyed, hazardous substances and immune cells will enter seminiferous tubule and cause adversely reproductive effects. In addition, PM2.5 also has shown to cause cells and tissues injury via inducing autophagy, inflammation, sex hormones disorder, and oxidative stress. However, the exact mechanisms of the disruption of the BTB, induced by PM2.5, are still unclear. It is suggested that more research is required to identify the potential mechanisms. In this review, we aim to understand the adverse effects on the BTB after exposure to PM2.5 and explore its potential mechanisms, which provides novel insight into accounting for PM2.5-induced BTB injury.

Challenges of Air Pollution and Health in East Asia

PURPOSE OF REVIEW

Air pollution has been a serious environmental and public health issue worldwide, particularly in Asian countries. There have been significant increases in epidemiological studies on fine particulate matter (PM2.5) and ozone pollution in East Asia, and an in-depth review of epidemiological evidence is urgent. Thus, we carried out a systematic review of the epidemiological research on PM2.5 and ozone pollution in East Asia released in recent years.

RECENT FINDINGS

Recent studies have indicated that PM2.5 and ozone are the most detrimental air pollutants to human health, resulting in substantial disease burdens for Asian populations. Many epidemiological studies of PM2.5 and ozone have been mainly performed in three East Asian countries (China, Japan, and South Korea). We derived the following summary findings: (1) both short-term and long-term exposure to PM2.5 and ozone could raise the risks of mortality and morbidity, emphasizing the need for continuing improvements in air quality in East Asia; (2) the long-term associations between PM2.5 and mortality in East Asia are comparable to those observed in Europe and North America, whereas the short-term associations are relatively smaller in magnitude; and (3) further cohort and intervention studies are required to yield robust and precise evidence that can promote evidence-based policymaking in East Asia. This updated review presented an outline of the health impacts of PM2.5 and ozone in East Asia, which may be beneficial for the development of future regulatory policies and standards, as well as for designing subsequent investigations.

Impact of altitude on the dosage of indoor particulates entering an individual's small airways

The complexity of indoor particulate exposure intensifies at higher altitudes owing to the increased lung capacity that residents develop to meet the higher oxygen demands. Altitude variations impact atmospheric pressure and alter particulate dynamics in ambient air and the human respiratory tract, complicating particulate inhalation. This study assessed the fraction of PM2.5 and PM10 entering small airways. This assessment covered an altitude range from 400 m above sea level to 3650 m, and an in vitro respiratory tract model was used. The experimental results confirmed that with increasing altitude, the penetration fractions of PM2.5 and PM10 significantly increased from 0.133 ± 0.031 and 0.141 ± 0.045 to 0.404 ± 0.159 and 0.353 ± 0.132, respectively. Additionally, the computational fluid dynamics simulation results revealed that among particles with sizes of 0.1 to 10 µm, the 7.5-μm particles exhibited the most substantial reduction in deposition in the upper airway, displaying a decrease of 6.27%. Our findings underscore the health risks faced by low-altitude residents during acclimatization to higher altitudes, as they experience heightened exposure to particulate matter sources.

Deciphering exogenous chemical carcinogenicity through interpretable deep learning: A novel approach for evaluating atmospheric pollutant hazards

Cancer remains a significant global health concern, with millions of deaths attributed to it annually. Environmental pollutants play a pivotal role in cancer etiology and contribute to the growing prevalence of this disease. The carcinogenic assessment of these pollutants is crucial for chemical health evaluation and environmental risk assessments. Traditional experimental methods are expensive and time-consuming, prompting the development of alternative approaches such as in silico methods. In this regard, deep learning (DL) has shown potential but lacks optimal performance and interpretability. This study introduces an interpretable DL model called CarcGC for chemical carcinogenicity prediction, utilizing a graph convolutional neural network (GCN) that employs molecular structural graphs as inputs. Compared to existing models, CarcGC demonstrated enhanced performance, with the area under the receiver operating characteristic curve (AUCROC) reaching 0.808 on the test set. Due to air pollution is closely related to the incidence of lung cancers, we applied the CarcGC to predict the potential carcinogenicity of chemicals listed in the United States Environmental Protection Agency's Hazardous Air Pollutants (HAPs) inventory, offering a foundation for environmental carcinogenicity screening. This study highlights the potential of artificially intelligent methods in carcinogenicity prediction and underscores the value of CarcGC interpretability in revealing the structural basis and molecular mechanisms underlying chemical carcinogenicity.

Burden of lung cancer attributed to particulate matter pollution in China: an epidemiological study from 1990 to 2019

OBJECTIVES

The aim of this study was to examine the disease burden of lung cancer attributable to particulate matter (PM2.5) pollution in China from 1990 to 2019.

STUDY DESIGN

Data from the Global Burden of Disease Study 2019 were used to estimate the disease burden of tracheal, bronchus and lung cancer attributed to PM2.5 over time in China.

METHODS

Joinpoint regression models were applied to disability-adjusted life years (DALYs) to assess the time trends and estimate the impact of PM2.5 on the overall disease burden of lung cancer. Furthermore, age-period-cohort models were conducted to assess the relationships between lung cancer DALYs attributed to PM2.5 exposure and age, calendar period and birth cohort trends in China from 1990 to 2019.

RESULTS

Lung cancer DALYs attributable to household air pollution from solid fuels decreased with an average annual percent change (AAPC) of 2.9 % per 100,000 population, while those attributable to ambient particular matter pollution (APE) increased (AAPC: -4.7 % per 100,000 population) over the past 30 years. The burden of lung cancer in terms of DALYs in males was higher than in females, and it demonstrated an age-dependent increase. The period and cohort effects also had significant impacts on the DALYs rates of lung cancer attributable to APE, indicating an overall increase in lung cancer DALYs for all age groups in each year.

CONCLUSIONS

This study highlights the need for effective strategies to reduce PM2.5 exposure in China, particularly from outdoor sources. Gender differences and age, period and cohort effects observed in the study provide valuable insights into long-term trends of lung cancer burden attributed to PM2.5.

Potential causal links of long-term air pollution with lung cancer incidence: From the perspectives of mortality and hospital admission in a large cohort study in southern China

Evidence on the potential causal links of long-term air pollution exposure with lung cancer incidence (reflected by mortality and hospital admission) was limited, especially based on large cohorts. We examined the relationship between lung cancer and long-term exposure to particulate matter (PM, including PM2.5 , PM10 and PM10-2.5 ) and nitrogen dioxide (NO2 ) among a large cohort of general Chinese adults using causal inference approaches. The study included 575 592 participants who were followed up for an average of 8.2 years. The yearly exposure of PM and NO2 was estimated through satellite-based random forest approaches and the ordinary kriging method, respectively. Marginal structural Cox models were used to examine hazard ratios (HRs) of mortality and hospital admission due to lung cancer following air pollution exposure, adjusting for potential confounders. The HRs of mortality due to lung cancer were 1.042 (95% confidence interval [CI]: 1.033-1.052), 1.032 (95% CI:1.024-1.041) and 1.052 (95% CI:1.041-1.063) for each 1 μg/m3 increase in PM2.5 , PM10 and NO2 , respectively. In addition, we observed statistically significant effects of PMs on hospital admission due to lung cancer. The HRs (95%CI) were 1.110 (1.027-1.201), 1.067 (1.020-1.115) and 1.079 (1.010-1.153) for every 1 μg/m3 increase in PM2.5 , PM10 , PM10-2.5 , respectively. Furthermore, we found larger effect estimates among the elderly and those who exercised more frequently. We provided the most comprehensive evidence of the potential causal links between two outcomes of lung cancer and long-term air pollution exposure. Relevant policies should be developed, with special attention to protecting the vulnerable groups of the population.

Exposure to outdoor particulate matter and risk of respiratory diseases: a systematic review and meta-analysis

According to epidemiological studies, particulate matter (PM) is an important air pollutant that poses a significant threat to human health. The relationship between particulate matter and respiratory diseases has been the subject of numerous studies, but these studies have produced inconsistent findings. The purpose of this systematic review was to examine the connection between outdoor particulate matter (PM2.5 and PM10) exposure and respiratory disorders (COPD, lung cancer, LRIs, and COVID-19). For this purpose, we conducted a literature search between 2012 and 2022 in PubMed, Web of Science, and Scopus. Out of the 58 studies that were part of the systematic review, meta-analyses were conducted on 53 of them. A random effect model was applied separately for each category of study design to assess the pooled association between exposure to PM2.5 and PM10 and respiratory diseases. Based on time-series and cohort studies, which are the priorities of the strength of evidence, a significant relationship between the risk of respiratory diseases (COPD, lung cancer, and COVID-19) was observed (COPD: pooled HR = 1.032, 95% CI: 1.004-1.061; lung cancer: pooled HR = 1.017, 95% CI: 1.015-1.020; and COVID-19: pooled RR = 1.004, 95% CI: 1.002-1.006 per 1 μg/m3 increase in PM2.5). Also, a significant relationship was observed between PM10 and respiratory diseases (COPD, LRIs, and COVID-19) based on time-series and cohort studies. Although the number of studies in this field is limited, which requires more investigations, it can be concluded that outdoor particulate matter can increase the risk of respiratory diseases.

Ethnic differences of genetic risk and smoking in lung cancer: two prospective cohort studies

BACKGROUND

The role of genetic background underlying the disparity of relative risk of smoking and lung cancer between European populations and East Asians remains unclear.

METHODS

To assess the role of ethnic differences in genetic factors associated with smoking-related risk of lung cancer, we first constructed ethnic-specific polygenic risk scores (PRSs) to quantify individual genetic risk of lung cancer in Chinese and European populations. Then, we compared genetic risk and smoking as well as their interactions on lung cancer between two cohorts, including the China Kadoorie Biobank (CKB) and the UK Biobank (UKB). We also evaluated the absolute risk reduction over a 5-year period.

RESULTS

Differences in compositions and association effects were observed between the Chinese-specific PRSs and European-specific PRSs, especially for smoking-related loci. The PRSs were consistently associated with lung cancer risk, but stronger associations were observed in smokers of the UKB [hazard ratio (HR) 1.26 vs 1.15, P  =  0.028]. A significant interaction between genetic risk and smoking on lung cancer was observed in the UKB (RERI, 11.39 (95% CI, 7.01-17.94)], but not in the CKB. Obvious higher absolute risk was observed in nonsmokers of the CKB, and a greater absolute risk reduction was found in the UKB (10.95 vs 7.12 per 1000 person-years, P <0.001) by comparing heavy smokers with nonsmokers, especially for those at high genetic risk.

CONCLUSIONS

Ethnic differences in genetic factors and the high incidence of lung cancer in nonsmokers of East Asian ethnicity were involved in the disparity of smoking-related risk of lung cancer.

Exploring the association of PM2.5 with lung cancer incidence under different climate zones and socioeconomic conditions from 2006 to 2016 in China

Air pollution generated by urbanization and industrialization poses a significant negative impact on public health. Particularly, fine particulate matter (PM2.5) has become one of the leading causes of lung cancer mortality worldwide. The relationship between air pollutants and lung cancer has aroused global widespread concerns. Currently, the spatial agglomeration dynamic of lung cancer incidence (LCI) has been seldom discussed, and the spatial heterogeneity of lung cancer's influential factors has been ignored. Moreover, it is still unclear whether different socioeconomic levels and climate zones exhibit modification effects on the relationship between PM2.5 and LCI. In the present work, spatial autocorrelation was adopted to reveal the spatial aggregation dynamic of LCI, the emerging hot spot analysis was introduced to indicate the hot spot changes of LCI, and the geographically and temporally weighted regression (GTWR) model was used to determine the affecting factors of LCI and their spatial heterogeneity. Then, the modification effects of PM2.5 on the LCI under different socioeconomic levels and climatic zones were explored. Some findings were obtained. The LCI demonstrated a significant spatial autocorrelation, and the hot spots of LCI were mainly concentrated in eastern China. The affecting factors of LCI revealed an obvious spatial heterogeneity. PM2.5 concentration, nighttime light data, 2 m temperature, and 10 m u-component of wind represented significant positive effects on LCI, while education-related POI exhibited significant negative effects on LCI. The LCI in areas with low urbanization rates, low education levels, and extreme climate conditions was more easily affected by PM2.5 than in other areas. The results can provide a scientific basis for the prevention and control of lung cancer and related epidemics.

Association between angiotensin-converting enzyme inhibitor-induced cough and the risk of lung cancer: a Mendelian randomization study

Background: Observational studies and meta-analyses have demonstrated a positive correlation between the use of angiotensin-converting enzyme inhibitors (ACEIs) and lung cancer. However, the findings remain controversial; furthermore, the relationship between ACEI-induced cough and lung cancer development remains unknown. We used Mendelian randomization (MR) to verify the association between ACEI use, ACEI-induced cough, and the risk of lung cancer. Methods: We performed a two-sample MR analysis to determine the unconfounded relationships between ACE inhibition, which mimics the effects of ACEIs, and genetic proxies for ACEI-induced cough and lung cancer. Single nucleotide polymorphisms that imitate ACE receptors and ACEI-induced cough were collected and integrated into a meta-analysis of existing genome-wide association studies for various lung cancers. The relationship was quantified using inverse variance weighting, weighted median, and MR-Egger methods. Results: A statistically significant association was observed between ACE inhibition and the risk of small cell lung cancer for Europeans (excluding rs118121655/rs80311894). Associations were identified between ACEI-induced cough and the risk of lung cancer for Europeans, although not for Asians, and between ACEI-induced cough and lung adenocarcinoma (excluding rs360206). Conclusion: Our findings reveal a relationship between ACE inhibition and lung cancer development, as well as a significant association between ACEI-induced cough and a higher risk of lung cancer for Europeans. Patients with hypertension who experience dry cough as a side effect of ACEI use should consider switching to an alternative antihypertensive treatment.

Changing profile of lung cancer clinical characteristics in China: Over 8-year population-based study

Background

Although examinations and therapies for bronchial lung cancer, also called lung cancer (LC), have become more effective and precise, the morbidity and mortality of LC remain high worldwide. Describing the changing profile of LC characteristics over time is indispensable. This study aimed to understand the changes in real-world settings of LC and its characteristics in China.

Methods

In this study, 119,785 patients were enrolled from 2012 to 2020 in the Shanghai Pulmonary Hospital. The patients' medical records were extracted from the hospital's database. Demographic characteristics, general clinicopathological information, and blood coagulation indices at the initial diagnoses were analyzed using the Kruskal-Wallis, Nemenyi, chi-squared, and Bonferroni tests. Changes in demographic characteristics during the 8-year study period, namely dynamic changes among different stages and different pathological types, were evaluated.

Results

The percentages of female (from 38.50% [323/839] in 2012 to 48.29% [5112/10,585] in 2020) and non-smoking LC (from 69.34% [475/685] to 80.48% [8055/10,009]) patients increased significantly during the study period, with a trend toward a younger age at diagnosis (from 3.58% [30/839] to 8.99% [952/10,585]). Over the study period, the proportion and absolute number of lung adenocarcinoma cases increased (from 67.97% [433/637] to 76.31% [6606/8657]) while the proportion of lung squamous cell carcinoma decreased (from 21.19% [135/637] to 12.08% [1046/8657]). Comprehensive driver gene mutation examination became more common, and epidermal growth factor receptor (EGFR) mutation occurred more frequently in female vs. male (62.03% [12793/20625] vs. 29.90% [8207/27,447]) and non-smoking vs. smoking (53.54% [17,203/32,134] vs. 23.73% [3322/13,997]) patients (both P < 0.001). The distribution of the common driver genes differed among different stages of LC. EGFR mutation was detected most frequently at each stage, and other driver gene alterations were more common in advanced stages (P <0.001). The combination of chemotherapy, targeted therapy, and immunotherapy, as a comprehensive management regimen, gradually became predominant over the study period (P < 0.001). A hypercoagulable state was shown in advanced-stage LC patients and patients with the anaplastic lymphoma kinase fusion, indicated by significantly elevated levels of d-dimer, fibrinogen, and fibrinogen degradation products.

Conclusions

This study comprehensively depicted the changing characteristics of Chinese LC patients over an 8-year period to provide preliminary insights into LC treatment.Trial registration: ClinicalTrials.gov, NCT05423236.

Ambient black carbon particles in human ovarian tissue and follicular fluid

Evidence indicates a link between exposure to ambient air pollution and decreased female fertility. The ability of air pollution particles to reach human ovarian tissue and follicles containing the oocytes in various maturation stages has not been studied before. Particulate translocation might be an essential step in explaining reproductive toxicity and assessing associated risks. Here, we analysed the presence of ambient black carbon particles in (i) follicular fluid samples collected during ovum pick-up from 20 women who underwent assisted reproductive technology treatment and (ii) adult human ovarian tissue from 5 individuals. Follicular fluid and ovarian tissue samples were screened for the presence of black carbon particles from ambient air pollution using white light generation by carbonaceous particles under femtosecond pulsed laser illumination. We detected black carbon particles in all follicular fluid (n = 20) and ovarian tissue (n = 5) samples. Black carbon particles from ambient air pollution can reach the ovaries and follicular fluid, directly exposing the ovarian reserve and maturing oocytes. Considering the known link between air pollution and decreased fertility, the impact of such exposure on oocyte quality, ovarian ageing and fertility needs to be clarified urgently.

Long-Term Exposure to Fine Particulate Matter and Incidence of Esophageal Cancer: A Prospective Study of 0.5 Million Chinese Adults

BACKGROUND & AIMS

Evidence is sparse and inconclusive on the association between long-term fine (≤2.5 μm) particulate matter (PM2.5) exposure and esophageal cancer. We aimed to assess the association of PM2.5 with esophageal cancer risk and compared the esophageal cancer risk attributable to PM2.5 exposure and other established risk factors.

METHODS

This study included 510,125 participants without esophageal cancer at baseline from China Kadoorie Biobank. A high-resolution (1 × 1 km) satellite-based model was used to estimate PM2.5 exposure during the study period. Hazard ratios (HR) and 95% CIs of PM2.5 with esophageal cancer incidence were estimated using Cox proportional hazard model. Population attributable fractions for PM2.5 and other established risk factors were estimated.

RESULTS

There was a linear concentration-response relationship between long-term PM2.5 exposure and esophageal cancer. For each 10-μg/m3 increase in PM2.5, the HR was 1.16 (95% CI, 1.04-1.30) for esophageal cancer incidence. Compared with the first quarter of PM2.5 exposure, participants in the highest quarter had a 1.32-fold higher risk for esophageal cancer, with an HR of 1.32 (95% CI, 1.01-1.72). The population attributable risk because of annual average PM2.5 concentration ≥35 μg/m3 was 23.3% (95% CI, 6.6%-40.0%), higher than the risks attributable to lifestyle risk factors.

CONCLUSIONS

This large prospective cohort study of Chinese adults found that long-term exposure to PM2.5 was associated with an elevated risk of esophageal cancer. With stringent air pollution mitigation measures in China, a large reduction in the esophageal cancer disease burden can be expected.

Effect of high-level PM2.5 on survival in lung cancer: a multicenter cohort study from Hebei Province, China

Globally, air pollution is the fourth leading risk factor for death, while lung cancer (LC) is the leading cause of cancer-related death. The aim of this study was to explore the prognostic factors of LC and the influence of high fine particulate matter (PM2.5) on LC survival. Data on LC patients were collected from 133 hospitals across 11 cities in Hebei Province from 2010 to 2015, and survival status was followed up until 2019. The personal PM2.5 exposure concentration (μg/m3) was matched according to the patient's registered address, calculated from a 5-year average for every patient, and stratified into quartiles. The Kaplan-Meier method was used to estimate overall survival (OS), and Cox's proportional hazard regression model was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). The 1-, 3-, and 5-year OS rates of the 6429 patients were 62.9%, 33.2%, and 15.2%, respectively. Advanced age (75 years or older: HR = 2.34, 95% CI: 1.25-4.38), subsite at overlapping (HR = 4.35, 95% CI: 1.70-11.1), poor/undifferentiated differentiation (HR = 1.71, 95% CI: 1.13-2.58), and advanced stages (stage III: HR = 2.53, 95% CI: 1.60-4.00; stage IV: HR = 4.00, 95% CI: 2.63-6.09) were risk factors for survival, while receiving surgical treatment was a protective factor (HR = 0.60, 95% CI: 0.44-0.83). Patients exposed to light pollution had the lowest risk of death with a 26-month median survival time. The risk of death in LC patients was greatest at PM2.5 concentrations of 98.7-108.9 μg/m3, especially for patients at advanced stage (HR = 1.43, 95% CI: 1.29-1.60). Our study indicates that the survival of LC is severely affected by relatively high levels of PM2.5 pollution, especially in those with advanced-stage cancer.

Haze Exposure Changes the Skin Fungal Community and Promotes the Growth of Talaromyces Strains

Haze pollution has been a public health issue. The skin microbiota, as a component of the first line of defense, is disturbed by environmental pollutants, which may have an impact on human health. A total of 74 skin samples from healthy students were collected during haze and nonhaze days in spring and winter. Significant differences of skin fungal community composition between haze and nonhaze days were observed in female and male samples in spring and male samples in winter based on unweighted UniFrac distance analysis. Phylogenetic diversity whole-tree indices and observed features were significantly increased during haze days in male samples in winter compared to nonhaze days, but no significant difference was observed in other groups. Dothideomycetes, Capnodiales, Mycosphaerellaceae, etc. were significantly enriched during nonhaze days, whereas Trichocomaceae, Talaromyces, and Pezizaceae were significantly enriched during haze days. Thus, five Talaromyces strains were isolated, and an in vitro culture experiment revealed that the growth of representative Talaromyces strains was increased at high concentrations of particulate matter, confirming the sequencing results. Furthermore, during haze days, the fungal community assembly was better fitted to a niche-based assembly model than during nonhaze days. Talaromyces enriched during haze days deviated from the neutral assembly process. Our findings provided a comprehensive characterization of the skin fungal community during haze and nonhaze days and elucidated novel insights into how haze exposure influences the skin fungal community. IMPORTANCE Skin fungi play an important role in human health. Particulate matter (PM), the main haze pollutant, has been a public environmental threat. However, few studies have assessed the effects of air pollutants on skin fungi. Here, haze exposure influenced the diversity and composition of the skin fungal community. In an in vitro experiment, a high concentration of PM promoted the growth of Talaromyces strains. The fungal community assembly is better fitted to a niche-based assembly model during haze days. We anticipate that this study may provide new insights on the role of haze exposure disturbing the skin fungal community. It lays the groundwork for further clarifying the association between the changes of the skin fungal community and adverse health outcomes. Our study is the first to report the changes in the skin fungal community during haze and nonhaze days, which expands the understanding of the relationship between haze and skin fungi.

Are children with sickle cell disease at particular risk from the harmful effects of air pollution? Evidence from a large, urban/peri-urban cohort

INTRODUCTION

Pathophysiologic pathways of sickle cell disease (SCD) and air pollution involve inflammation, oxidative stress, and endothelial damage. It is therefore plausible that children with SCD are especially prone to air pollution's harmful effects.

METHODS

Patient data were collected from a single-center, urban/peri-urban cohort of children with confirmed SCD. Daily ambient concentrations of particulate matter (PM2.5 ) were collected via satellite-derived remote-sensing technology, and carbon monoxide (CO), nitrogen dioxide (NO2 ), and ozone from local monitoring stations. We used multivariable regression to quantify associations of pollutant levels and daily counts of emergency department (ED) visits, accounting for weather and time trends. For comparison, we quantified the associations of pollutant levels with daily all-patient (non-SCD) ED visits to our center.

RESULTS

From 2010 to 2018, there were 17,731 ED visits by 1740 children with SCD (64.8% HbSS/HbSβ0 ). Vaso-occlusive events (57.8%), respiratory illness (17.1%), and fever (16.1%) were the most common visit diagnoses. Higher 3-day (lags 0-2) rolling mean PM2.5 and CO levels were associated with daily ED visits among those with SCD (PM2.5 incident rate ratio [IRR] 1.051 [95% confidence interval: 1.010-1.094] per 9.4 μg/m3 increase; CO 1.088 [1.045-1.132] per 0.5 ppm). NO2 showed positive associations in secondary analyses; ozone levels were not associated with ED visits. The comparison, all-patient ED visit analyses showed lower IRR for all pollutants.

CONCLUSIONS

Our results suggest short-term air pollution levels as triggers for SCD events and that children with SCD may be more vulnerable to air pollution than those without SCD. Targeted pollution-avoidance strategies could have significant clinical benefits in this population.

Long-term exposure to fine particulate matter and site-specific cancer mortality: A difference-in-differences analysis in Jiangsu province, China

BACKGROUND

Accumulating studies have reported that chronic exposure to ambient fine particulate matter (PM_2.5) can lead to adverse effects on lung cancer mortality; however, such chronic effects are less clear for mortality from other site-specific cancers.

OBJECTIVE

To explore the causal effect of long-term PM_2.5 exposure on mortality from all-site and a variety of site-specific cancers in Jiangsu province, China during 2015-2020 using a difference-in-differences analysis.

METHODS

For each of 53 county-based spatial units in Jiangsu province, we calculated annual death counts for all-site cancer and 23 site-specific cancers. Using a validated high-resolution PM_2.5 grid dataset, long-term PM_2.5 exposure of a spatial unit within a given year was evaluated as the average of population-weighted annual concentrations during recent 10 years. Conditional Poisson regression models were employed to evaluate exposure-response associations adjusting for spatial and temporal variables, seasonal temperatures, relative humidity, and gross domestic product (GDP).

RESULTS

During the study period, we identified 947,337 adult cancer deaths in Jiangsu province. Each 1 μg/m³ increment in PM_2.5 exposure was significantly associated with a 2.7% increase in the risk of all-site cancer mortality. PM_2.5-mortality associations were also observed in cancer of lip, oral cavity and pharynx, stomach, colorectum, pancreas, lung, bone and joints, ovary, prostate, and lymphoma (all adjusted P < 0.05), with the relative risks ranging from 1.028 (95% confidence interval [CI]: 1.011, 1.046) for stomach cancer to 1.201 (95% CI: 1.120, 1.308) for bone and joints cancers. Exposure-response curves showed that these associations were close to linearity, though most of them had increasing slopes at high exposure levels. Overall, women and subjects in low GDP regions were more vulnerable to PM_2.5 exposures.

CONCLUSIONS

Long-term exposure to ambient PM_2.5 contributes to a higher risk of mortality from multiple site-specific cancers.

Long-term exposure to particulate matter on cardiovascular and respiratory diseases in low- and middle-income countries: A systematic review and meta-analysis

Background

Long-term exposure to particulate matter (PM) has essential and profound effects on human health, but most current studies focus on high-income countries. Evidence of the correlations between PM and health effects in low- and middle-income countries (LMICs), especially the risk factor PM1 (particles &lt; 1 μm in size), remains unclear.

Objective

To explore the effects of long-term exposure to particulate matter on the morbidity and mortality of cardiovascular and respiratory diseases in LMICs.

Methods

A systematic search was conducted in the PubMed, Web of Science, and Embase databases from inception to May 1, 2022. Cohort studies and case-control studies that examine the effects of PM1, PM2.5, and PM10 on the morbidity and mortality of cardiovascular and respiratory diseases in LMICs were included. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Outcomes were analyzed via a random effects model and are reported as the relative risk (RR) with 95% CI.

Results

Of the 1,978 studies that were identified, 38 met all the eligibility criteria. The studies indicated that long-term exposure to PM2.5, PM10, and PM1 was associated with cardiovascular and respiratory diseases: (1) Long-term exposure to PM2.5 was associated with an increased risk of cardiovascular morbidity (RR per 1.11 μg/m3, 95% CI: 1.05, 1.17) and mortality (RR per 1.10 μg/m3, 95% CI: 1.06, 1.14) and was significantly associated with respiratory mortality (RR 1.31, 95% CI: 1.25, 1.38) and morbidity (RR 1.08, 95% CI: 1.02, 1.04); (2) An increased risk of respiratory mortality was observed in the elderly (65+ years) (RR 1.21, 95% CI: 1.00, 1.47) with long-term exposure to PM2.5; (3) Long-term exposure to PM10 was associated with cardiovascular morbidity (RR 1.07, 95% CI 1.01, 1.13), respiratory morbidity (RR 1.43, 95% CI: 1.21, 1.69) and respiratory mortality (RR 1.28, 95% CI 1.10, 1.49); (4) A significant association between long-term exposure to PM1 and cardiovascular disease was also observed.

Conclusions

Long-term exposure to PM2.5, PM10 and PM1 was all related to cardiovascular and respiratory disease events. PM2.5 had a greater effect than PM10, especially on respiratory diseases, and the risk of respiratory mortality was significantly higher for LMICs than high-income countries. More studies are needed to confirm the effect of PM1 on cardiovascular and respiratory diseases.

Correlation Between Air Quality Index and Tear Film Lipid Layer Thickness: Comparison Between Patients with Sjogren's Syndrome and with Meibomian Gland Dysfunction

Purpose: To evaluate the effect of air pollution on the tear film stability by analyzing the correlation between Air Quality Index (AQI) and Lipid Layer thickness (LLT) in Xuzhou.Methods: As a prospective descriptive observational study, 284 patients with meibomian gland dysfunction (MGD), 157 patients with Sjögren's syndrome (SS), and 264 healthy volunteers were included. The tear film lipid layer thickness of the three groups of subjects was measured weekly and compared with the air quality index to analyze the correlation between the two indicators. Logistic regression analysis and linear regression analysis were used to analyze the effect of AQI on the thickness of the tear film lipid layer. The change of LLT with air pollution at different AQI levels was also analyzed.Results: There are obvious seasonal differences in the changes of air pollution index in Xuzhou. Significant differences could be observed in the thickness of the lipid layer of the tear film among the three groups. LLT in the MGD group and SS group decreased with the aggravation of air pollution, while remained unchanged in the control group. There was strong evidence of correlation between LLT of the MGD group (F = 353.494, p < 0.01, adjusted R2 = 0.695) and the SS group (F = 502.404, p < 0.01, adjusted R2 = 0.764) with AQI, while there was minor correlation between LLT with AQI in control group (F = 8.525, p < 0.01, adjusted R2 = 0.046).Conclusions: Air pollution can cause a decrease in the thickness of the tear film lipid layer, thereby affecting tear film stability, leading to the occurrence of dry eye.

IFI44L as a novel epigenetic silencing tumor suppressor promotes apoptosis through JAK/STAT1 pathway during lung carcinogenesis

Numerous evidence showed that the occurrence and development of lung cancer is closely related to environmental pollution. Therefore, new environmental response predictive markers are urgently needed for early diagnosis and screening of lung cancer. Interferon-induced protein 44-like (IFI44L) has been shown to be related in a variety of tumors, but its function and mechanism during lung carcinogenesis still have remained largely unknown. In this study, gene expression and methylation status were analyzed through online tools and malignant transformation models. Differentially expressed cell models and xenograft tumor models were established and used to clarify the gene function. RT-qPCR, western blotting, immunohistochemistry, and co-immunoprecipitation (Co-IP) were used to explore the mechanism. Results showed that IFI44L was dramatically downexpressed during lung carcinogenesis, and its low expression may be attributed to DNA methylation. Overexpression of IFI44L obviously inhibited cell growth and promoted apoptosis. After knockdown of IFI44L expression, the proliferation ability was remarkably increased and the apoptosis was significantly reduced. Functional enrichment showed that IFI44L was involved in apoptosis and JAK/STAT1 signaling pathway, and was highly correlated with downstream molecules. After overexpression of IFI44L, the expression of P-STAT1 and downstream molecules XAF1, OAS1, OAS2 and OAS3 were significantly increased. After knockdown of STAT1 expression, the pro-apoptotic effect of IFI44L was reduced. Co-IP results showed that IFI44L had protein interaction with STAT1. Results proved that IFI44L promoted STAT1 phosphorylation and activated the JAK/STAT1 signaling pathway by directly binding to STAT1 protein, thereby leading to cell apoptosis. Our study revealed that IFI44L promotes cell apoptosis and exerts tumor suppressors by activating the JAK/STAT1 signaling pathway. It further suggests that IFI44L has clinical therapeutic potential and may be a promising biomarker during lung carcinogenesis.

Ambient fine particulate matter and cardiopulmonary health risks in China

ABSTRACT

In China, the level of ambient fine particulate matter (PM 2.5 ) pollution far exceeds the air quality standards recommended by the World Health Organization. Moreover, the health effects of PM 2.5 exposure have become a major public health issue. More than half of PM 2.5 -related excess deaths are caused by cardiopulmonary disease, which has become a major health risk associated with PM 2.5 pollution. In this review, we discussed the latest epidemiological advances relating to the health effects of PM 2.5 on cardiopulmonary diseases in China, including studies relating to the effects of PM 2.5 on mortality, morbidity, and risk factors for cardiovascular and respiratory diseases. These data provided important evidence to highlight the cardiopulmonary risk associated with PM 2.5 across the world. In the future, further studies need to be carried out to investigate the specific relationship between the constituents and sources of PM 2.5 and cardiopulmonary disease. These studies provided scientific evidence for precise reduction measurement of pollution sources and public health risks. It is also necessary to identify effective biomarkers and elucidate the biological mechanisms and pathways involved; this may help us to take steps to reduce PM 2.5 pollution and reduce the incidence of cardiopulmonary disease.

Fine particulate matter and cardiorespiratory health in China: A systematic review and meta-analysis of epidemiological studies

This review aimed to systematically summarize the epidemiological literature on the cardiorespiratory effects of PM_2.5 published during the 13^th Five-Year Plan period (2016-2020) in China. Original articles published between January 1, 2016 and June 30, 2021 were searched in PubMed, Web of Science, the China National Knowledge Internet Database and Wanfang Database. Random- or fixed-effects models were used to pool effect estimates where appropriate. Of 8558 records identified, 145 met the full eligibility criteria. A 10 µg/m³ increase in short-term PM_2.5 exposure was significantly associated with increases of 0.70%, 0.86%, 0.38% and 0.96% in cardiovascular mortality, respiratory mortality, cardiovascular morbidity, and respiratory morbidity, respectively. The specific diseases with significant associations included stroke, ischemic heart disease, heart failure, arrhythmia, chronic obstructive pulmonary disease, pneumonia and allergic rhinitis. The pooled estimates per 10 µg/m³ increase in long-term PM_2.5 exposure were 15.1%, 11.9% and 21.0% increases in cardiovascular, stroke and lung cancer mortality, and 17.4%, 11.0% and 4.88% increases in cardiovascular, hypertension and lung cancer incidence respectively. Adverse changes in blood pressure, heart rate variability, systemic inflammation, blood lipids, lung function and airway inflammation were observed for either short-term or long-term PM_2.5 exposure, or both. Collectively, we summarized representative exposure-response relationships between short- and long-term PM_2.5 exposure and a wide range of cardiorespiratory outcomes applicable to China. The magnitudes of estimates were generally smaller in short-term associations and comparable in long-term associations compared with those in developed countries. Our findings are helpful for future standard revisions and policy formulation. There are still some notable gaps that merit further investigation in China.

Neurodevelopmental toxicity induced by airborne particulate matter

Airborne particulate matter (PM), the primary component associated with health risks in air pollution, can negatively impact human health. Studies have shown that PM can enter the brain by inhalation, but data on the exact quantity of particles that reach the brain are unknown. Particulate matter exposure can result in neurotoxicity. Exposure to PM poses a greater health risk to infants and children because their nervous systems are not fully developed. This review paper highlights the association between PM and neurodevelopmental toxicity (NDT). Exposure to PM can induce oxidative stress and inflammation, potentially resulting in blood-brain barrier damage and increased susceptibility to development of neurodevelopmental disorders (NDD), such as autism spectrum disorders and attention deficit disorders. In addition, human and animal exposure to PM can induce microglia activation and epigenetic alterations and alter the neurotransmitter levels, which may increase risks for development of NDD. However, the systematic comparisons of the effects of PM on NDD at different ages of exposure are deficient. The elucidation of PM exposure risks and NDT in children during the early developmental stages are of great importance. The synthesis of current research may help to identify markers and mechanisms of PM-induced neurodevelopmental toxicity, allowing for the development of strategies to prevent permanent damage of developing brain.

Overview of particulate air pollution and human health in China: Evidence, challenges, and opportunities

Ambient particulate matter (PM) pollution in China continues to be a major public health challenge. With the release of the new WHO air quality guidelines in 2021, there is an urgent need for China to contemplate a revision of air quality standards (AQS). In the recent decade, there has been an increase in epidemiological studies on PM in China. A comprehensive evaluation of such epidemiological evidence among the Chinese population is central for revision of the AQS in China and in other developing countries with similar air pollution problems. We thus conducted a systematic review on the epidemiological literature of PM published in the recent decade. In summary, we identified the following: (1) short-term and long-term PM exposure increase mortality and morbidity risk without a discernible threshold, suggesting the necessity for continuous improvement in air quality; (2) the magnitude of long-term associations with mortality observed in China are comparable with those in developed countries, whereas the magnitude of short-term associations are appreciably smaller; (3) governmental clean air policies and personalized mitigation measures are potentially effective in protecting public and individual health, but need to be validated using mortality or morbidity outcomes; (4) particles of smaller size range and those originating from fossil fuel combustion appear to show larger relative health risks; and (5) molecular epidemiological studies provide evidence for the biological plausibility and mechanisms underlying the hazardous effects of PM. This updated review may serve as an epidemiological basis for China’s AQS revision and proposes several perspectives in designing future health studies.

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Acute effects of PM are smaller in China compared with developed countries

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Health effects caused by PM depend on particle composition, source, and size

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There are no thresholds for the health effects of PM

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Mechanistic studies support the biological plausibility of PM’s health effects

PM2.5 exposure and risk of lung adenocarcinoma in women of Taiwan: A case-control study with density sampling

BACKGROUND AND OBJECTIVE

The prevalence of smoking among women in Taiwan is <5%, but the incidence of lung cancer remains high. This study determined the association between PM_2.5 (fine particulate matter with an aerodynamic diameter of ≤2.5 μm) exposure and lung cancer among women in Taiwan.

METHODS

In total, 21,301 female lung cancer cases nationwide were newly diagnosed between 2012 and 2017. Each case was age-, sex- and calendar year-matched with four controls randomly selected from the general population. Allowing a latent period of 5 years, we estimated the PM_2.5 and nitrogen dioxide (NO₂ ) exposures for each individual according to the residential changes from 2000. We adopted self-reported smoking statuses for the cases, while those of controls were estimated using annual surveys in each residential county. We performed multiple logistic regression analyses to examine the associations between PM_2.5 and NO₂ exposures and incident lung cancer cases.

RESULTS

The ORs of lung adenocarcinoma for the third (30.5-35.1 μg/m³ ), fourth (35.1-39.3 μg/m³ ) and fifth PM_2.5 exposure quintiles (39.3-48.1 μg/m³ ) relative to the first quintile were 1.10 (95% CI: 1.04-1.16), 1.12 (95% CI: 1.06-1.19) and 1.10 (95% CI: 1.04-1.16), respectively, after adjusting for smoking, residence and comorbidities. A dose-response relationship (p = 0.004) was found. The associations persisted with a 10-year latency and were not detected for small-cell and squamous cell carcinoma after control for smoking. We did not observe a similar effect for NO₂ exposure.

CONCLUSION

Residential PM_2.5 exposure higher than 30 μg/m³ was associated with an increased risk of lung adenocarcinoma in women of Taiwan.

Aberrant mitochondrial DNA methylation and declined pulmonary function in a population with polycyclic aromatic hydrocarbon composition in particulate matter

Air pollution exposure has been found to be associated with epigenetic modification of the mitochondrial genome, which could subsequently induce adverse health outcomes. However, very limited studies exist regarding the association between fine particulate matter (PM_2.5) exposure and pulmonary function at the molecular level of mitochondrial epigenetic changes. This study aimed to investigate the association of platelet mitochondrial DNA (mtDNA) methylation with occupational PM_2.5 exposure and pulmonary function. First, 768 participants were occupationally exposed to polycyclic aromatic hydrocarbon (PAH)-enriched PM_2.5 in a coke-oven plant in East China. The levels of PM_2.5, PAH components bound to PM_2.5, and urinary PAH metabolites in the workplace environment were measured as an internal dose, respectively. mtDNA methylation was measured by bisulfite pyrosequencing of two genes of ATP synthase (MT-ATP6 and MT-ATP8). Mediation analysis was conducted to evaluate the role of mtDNA methylation in pulmonary alteration induced by PAH. A decreasing trend of platelet mtDNA methylation was observed with increase in PM_2.5 exposure across all participants. As an important PAH metabolite in urine, 1-hydroxypyrene (1-OHP) was significantly negatively associated with FEV1/FVC (Forced Expiratory Volume in 1s/Forced Vital Capacity) ratio. The participants with high serum folate levels (≥10 nmol/L) showed positive association between MT-ATP6 methylation and FEV1/FVC ratio. Mediation analysis suggested that MT-ATP6 methylation mediated the significant association of urinary 1-OHP with FEV1/FVC. Our findings suggested the methylation of platelet mitochondrial gene MT-ATP6 and FEV1/FVC to be negatively associated with PM exposure. Platelet mtDNA methylation acted as an intermediary between PAH exposure and lung function decline. The mitochondrial epigenetic regulation in platelets, in response to PM exposure, might be involved in subsequent progress of abnormal pulmonary function.

PM2.5 exposure and cervical cancer survival in Liaoning Province, northeastern China

Particulate matter with a diameter of 2.5 μm or less (PM_2.5) has frequently been reported to be associated with an increased incidence of cancer, but few studies have explored the association between PM_2.5 exposure and cancer survival. We retrospectively analyzed the association between PM_2.5 exposure and the overall survival (OS) of cervical cancer patients residing in 14 urban areas of Liaoning Province, northeastern China, during January 2014-October 2021. Patients from urban areas who completed the recommended treatments with complete follow-up information were included. The PM_2.5 monitoring data of each urban area of Liaoning Province were retrieved, and individual exposure to PM_2.5 after diagnosis was calculated as the average daily concentration in the city of residence from the date of discharge to the date of death or the last follow-up. Log-rank tests and Cox regression were performed to examine the relationship between PM_2.5 exposure and cervical cancer survival. A total of 1753 cervical cancer patients were finally included, among whom 804 (45.9%) were from Shenyang City, the capital of Liaoning Province. The median average daily concentration of PM_2.5 to which the patients were exposed was 45.0 (interquartile range 38.2-50.0) μg/m³. Both log-rank tests (grouped by quartiles, p < 0.001) and Cox regression (continuous, HR = 1.06, 95% CI 1.04-1.08) indicated that PM_2.5 was significantly associated with shorter OS. Sensitivity analysis also confirmed the robustness of our findings. From the subgroup analysis, only the OS of stage II and stage III patients was associated with PM exposure. Our findings provide the insight that PM_2.5 exposure might be associated with shorter OS of cervical cancer patients.

Long-term PM2.5 exposure in association with chronic respiratory diseases morbidity: A cohort study in Northern China

Several literatures have examined the risk of chronic respiratory diseases in association with short-term ambient PM2.5 exposure in China. However, little evidence has examined the chronic impacts of PM2.5 exposure on morbidity of chronic respiratory diseases in cohorts from high pollution countries. Our study aims to investigate the associations. Based on a retrospective cohort among adults in northern China, a Cox regression model with time-varying PM2.5 exposure and a concentration-response (C-R) curve model were performed to access the relationships between incidence of chronic respiratory diseases and long-term PM2.5 exposure during a mean follow-up time of 9.8 years. Individual annual average PM2.5 estimates were obtained from a satellite-based model with high resolution. The incident date of a chronic respiratory disease was identified according to self-reported physician diagnosis time and/or intake of medication for treatment. Among 38,047 urban subjects analyzed in all-cause chronic respiratory disease cohort, 482 developed new cases. In CB (38,369), asthma (38,783), and COPD (38,921) cohorts, the onsets were 276, 89, and 14, respectively. After multivariable adjustment, hazard ratio and 95% confidence interval for morbidity of all-cause chronic respiratory disease, CB, asthma, and COPD were 1.15 (1.01, 1.31), 1.20 (1.00, 1.42), 0.76 (0.55, 1.04), and 0.66 (0.29, 1.47) with each 10 μg/m3 increment in PM2.5, respectively. Stronger effect estimates were suggested in alcohol drinkers across stratified analyses. Additionally, the shape of C-R curve showed an increasing linear relationship before 75.00 μg/m3 concentrations of PM2.5 for new-onset all-cause chronic respiratory disease, and leveled off at higher levels. These findings indicated that long-term exposure to high-level PM2.5 increased the risks of incident chronic respiratory diseases in China. Further evidence of C-R curves is warranted to clarify the associations of adverse chronic respiratory outcomes involving air pollution.

The Lung Microbiota Affects Pulmonary Inflammation and Oxidative Stress Induced by PM2.5 Exposure

Fine particulate matter (PM_2.5) exposure causes respiratory diseases by inducing inflammation and oxidative stress. However, the correlation between the pulmonary microbiota and the progression of pulmonary inflammation and oxidative stress caused by PM_2.5 is poorly understood. This study tested the hypothesis that the lung microbiota affects pulmonary inflammation and oxidative stress induced by PM_2.5 exposure. Mice were exposed to PM_2.5 intranasally for 12 days. Then, pulmonary microbiota transfer and antibiotic intervention were performed. Histological examinations, biomarker index detection, and transcriptome analyses were conducted. Characterization of the pulmonary microbiota using 16S rRNA gene sequencing showed that its diversity decreased by 75.2% in PM_2.5-exposed mice, with increased abundance of Proteobacteria and decreased abundance of Bacteroidota. The altered composition of the microbiota was significantly correlated with pulmonary inflammation and oxidative stress-related indicators. Intranasal transfer of the pulmonary microbiota from PM_2.5-exposed mice affected pulmonary inflammation and oxidative stress caused by PM_2.5, as shown by increased proinflammatory cytokine levels and dysregulated oxidative damage-related biomarkers. Antibiotic intervention during PM_2.5 exposure alleviated pulmonary inflammation and oxidative damage in mice. The pulmonary microbiota also showed substantial changes after antibiotic treatment, as reflected by the increased microbiota diversity, decreased abundance of Proteobacteria and increased abundance of Bacteroidota. These results suggest that pulmonary microbial dysbiosis can promote and affect pulmonary inflammation and oxidative stress during PM_2.5 exposure.

Comparing spatial patterns of 11 common cancers in Mainland China

BACKGROUND

A stronger spatial clustering of cancer burden indicates stronger environmental and human behavioral effects. However, which common cancers in China have stronger spatial clustering and knowledge gaps regarding the environmental and human behavioral effects have yet to be investigated. This study aimed to compare the spatial clustering degree and hotspot patterns of 11 common cancers in mainland China and discuss the potential environmental and behavioral risks underlying the patterns.

METHODS

Cancer incidence data recorded at 339 registries in 2014 was obtained from the "China Cancer Registry Annual Report 2017". We calculated the spatial clustering degree of the common cancers using the global Moran's Index and identified the hotspot patterns using the hotspot analysis.

RESULTS

We found that esophagus, stomach and liver cancer have a significantly higher spatial clustering degree ([Formula: see text]) than others. When by sex, female esophagus, male stomach, male esophagus, male liver and female lung cancer had significantly higher spatial clustering degree ([Formula: see text]). The spatial clustering degree of male liver was significantly higher than that of female liver cancer ([Formula: see text]), whereas the spatial clustering degree of female lung was significantly higher than that of male lung cancer ([Formula: see text]). The high-risk areas of esophagus and stomach cancer were mainly in North China, Huai River Basin, Yangtze River Delta and Shaanxi Province. The hotspots for liver and male liver cancer were mainly in Southeast China and south Hunan. Hotspots of female lung cancer were mainly located in the Pearl River Delta, Shandong, North and Northeast China. The Yangtze River Delta and the Pearl River Delta were high-risk areas for multiple cancers.

CONCLUSIONS

The top highly clustered cancer types in mainland China included esophagus, stomach and liver cancer and, by sex, female esophagus, male stomach, male esophagus, male liver and female lung cancer. Among them, knowledge of their spatial patterns and environmental and behavioral risk factors is generally limited. Potential factors such as unhealthy diets, water pollution and climate factors have been suggested, and further investigation and validation are urgently needed, particularly for male liver cancer. This study identified the knowledge gap in understanding the spatial pattern of cancer burdens in China and offered insights into targeted cancer monitoring and control.

Health Effects of Long-Term Exposure to Ambient PM2.5 in Asia-Pacific: a Systematic Review of Cohort Studies

Abstract

Purpose of Review

Health effects of long-term exposure to ambient PM_2.5 vary with regions, and 75% of the deaths attributable to PM_2.5 were estimated in Asia-Pacific in 2017. This systematic review aims to summarize the existing evidence from cohort studies on health effects of long-term exposure to ambient PM_2.5 in Asia-Pacific.

Recent Findings

In Asia-Pacific, 60 cohort studies were conducted in Australia, Mainland China, Hong Kong, Taiwan, and South Korea. They consistently supported associations of long-term exposure to PM_2.5 with increased all-cause/non-accidental and cardiovascular mortality as well as with incidence of cardiovascular diseases, type 2 diabetes mellitus, kidney diseases, and chronic obstructive pulmonary disease. Evidence for other health effects was limited. Inequalities were identified in PM_2.5-health associations.

Summary

To optimize air pollution control and public health prevention, further studies need to assess the health effects of long-term PM_2.5 exposure in understudied regions, the health effects of long-term PM_2.5 exposure on mortality and risk of type 2 diabetes mellitus, renal diseases, dementia and lung cancer, and inequalities in PM_2.5-health associations. Study design, especially exposure assessment methods, should be improved.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40572-022-00344-w.

Projecting Lifetime Health Outcomes and Costs Associated with the Ambient Fine Particulate Matter Exposure among Adult Women in Korea

We sought to estimate the lifetime healthcare costs and outcomes associated with the exposure to the escalated concentration of fine particulate matter (particle size < 2.5 μm, PM2.5) among adult Korean women. We adapted a previously developed Markov model, and a hypothetical cohort composed of Korean women was exposed to either a standard (15 μg/m3) or increased (25 μg/m3) concentration of PM2.5. The time horizon of the analysis was 60 years, and the cycle length was 1 year. The outcomes were presented as direct healthcare costs and quality-adjusted life years (QALYs), and costs were discounted annually at 5%. Deterministic and probabilistic sensitivity analyses were performed. The model estimated that when the exposure concentration was increased by 10 μg/m3, the lifetime healthcare cost increased by USD 9309, which is an 11.3% increase compared to the standard concentration group. Women exposed to a higher concentration of PM2.5 were predicted to live 30.64 QALYs, compared to 32.08 QALYs for women who were exposed to the standard concentration of PM2.5. The tendency of a higher cost and shorter QALYs at increased exposure was consistent across a broad range of sensitivity analyses. The negative impact of PM2.5 was higher on cost than on QALYs and accelerated as the exposure time increased, emphasizing the importance of early intervention.

Isolation, Characterization, and Antimicrobial Activity of Bacterial and Fungal Representatives Associated With Particulate Matter During Haze and Non-haze Days

Particulate matter (PM) has been a threat to the environment and public health in the metropolises of developing industrial countries such as Beijing. The microorganisms associated with PM have an impact on human health if they are exposed to the respiratory tract persistently. There are few reports on the microbial resources collected from PM and their antimicrobial activities. In this study, we greatly expanded the diversity of available commensal organisms by collecting 1,258 bacterial and 456 fungal isolates from 63 PM samples. A total of 77 bacterial genera and 35 fungal genera were included in our pure cultures, with Bacillus as the most prevalent cultured bacterial genus, Aspergillus, and Penicillium as the most prevalent fungal ones. During heavy-haze days, the numbers of colony-forming units (CFUs) and isolates of bacteria and fungi were decreased. Bacillus, Paenibacillus, and Chaetomium were found to be enriched during haze days, while Kocuria, Microbacterium, and Penicillium were found to be enriched during non-haze days. Antimicrobial activity against common pathogens have been found in 40 bacterial representatives and 1 fungal representative. The collection of airborne strains will provide a basis to greatly increase our understanding of the relationship between bacteria and fungi associated with PM and human health.

D-Limonene inhibits the occurrence and progression of LUAD through suppressing lipid droplet accumulation induced by PM2.5 exposure in vivo and in vitro

BACKGROUND

PM_2.5 exposure is associated with lung adenocarcinoma (LUAD), but the mechanism is unclear. The lack of understanding impedes our effort on prevention. This study examined a possible mechanism of lung cancer caused by PM_2.5 exposure, and aimed to find a potential intervention for people living in PM_2.5 polluted regions.

METHODS

Electron microscopy and oil-red staining were conducted to examine the lipid droplet accumulation. Masson's trichrome staining, colony forming, scratch assay and transwell experiment were conducted to evaluate the effect of PM_2.5 exposure and D-limonene intervention on the occurrence and progression of LUAD. Potential intervention targets were found by RNA-Seq and verified by luciferase reporter assay. MiR-195 KO mice constructed with CRISPR/Cas9 technology were used to investigate the pivotal role of D-limonene-miR-195-SREBP1/FASN axis. Cohort analysis of lung cancer patients, human LUAD tissues staining and human intervention trial were also conducted to validate the results of cell and animal experiments.

RESULTS

Our results showed that PM_2.5 exposure induced accumulation of lipid droplets in LUAD cells which accompanied by increased malignant cellular behaviors. PM_2.5 exposure led to cleaved N-SREBP1 translocation into nucleus, which activated the de novo lipogenesis pathway. Same changes were also observed in normal lung epithelial cells and normal lung tissue, and mice developed pulmonary fibrosis after long-term exposure to PM_2.5. Furthermore, in a cohort of 11,712 lung cancer patients, significant lipid metabolism disorders were observed in higher PM_2.5 polluted areas. In view of that, D-limonene was found to inhibit the changes in lipid metabolism through upregulating the expression of miR-195, which inhibited the expression of lipogenic genes (SREBF1/FASN/ACACA) specifically. And a small human intervention trial showed that serum miR-195 was upregulated after oral intake of D-limonene.

CONCLUSION

Our findings reveal a new mechanism of pulmonary fibrosis and LUAD that is related to PM_2.5 exposure-induced lipid droplet accumulation. We also demonstrate that D-limonene-miR-195-SREBP1/FASN axis is a potential preventive intervention for mediating the progression and development of LUAD induced by PM_2.5 exposure. Trial registration Chinese Clinical Trial Registry, ChiCTR2000030200. Registered 25 February 2020, http://www.chictr.org.cn/showproj.aspx?proj=48013.

Air Pollution, Genetic Factors and the Risk of Lung Cancer: A Prospective Study in the UK Biobank

Rationale: Both genetic and environmental factors contribute to lung cancer, but the degree to which air pollution modifies the impact of genetic susceptibility on lung cancer remains unknown. Objectives: To investigate whether air pollution and genetic factors jointly contribute to incident lung cancer. Methods: We analyzed data from 455,974 participants (53% women) without previous cancer at baseline in the UK Biobank. The concentrations of particulate matter (PM_2.5, PM_coarse and PM₁₀), nitrogen dioxide (NO₂), and nitrogen oxides (NO_x) were estimated by land-use regression models, and the association between air pollutants and incident lung cancer was investigated using a Cox proportional hazard model. Furthermore, we constructed a polygenic risk score and evaluated whether air pollutants modified the effect of genetic susceptibility on the development of lung cancer. Measurements and Main Results: The results showed significant associations between the risk of lung cancer and PM_2.5 (hazard ratio [HR]: 1.63, 95% confidence interval [CI]: 1.33-2.01; per 5 μg/m³), PM₁₀ (1.53, 1.20-1.96; per 10 μg/m³), NO₂ (1.10, 1.05-1.15; per 10 μg/m³), and NO_x (1.13, 1.07-1.18; per 20 μg/m³). There were additive interactions between air pollutants and the genetic risk. Compared with participants with low genetic risk and low air pollution, those with high air pollution and high genetic risk had the highest risk of lung cancer (PM_2.5: HR: 1.71, 95% CI:1.45-2.02; PM₁₀: 1.77, 1.50-2.10; NO₂: 1.77, 1.42-2.22; NO_x: 1.67, 1.43-1.95). Conclusion: Long-term exposure to air pollution may increase the risk of lung cancer, especially in those with high genetic risk.

lncRNA SOX2-OT ceRNA network enhances the malignancy of long-term PM2.5-exposed human bronchial epithelia

Exposure to fine particulate matter (PM_2.5) in outdoor air is carcinogenic and associated with the development of lung cancer; however, the underlying mechanism remains unclear. In the present study, the profiles of lncRNA, microRNA and mRNA expression profiles in human bronchial epithelia (HBE) following exposure to PM_2.5, diesel exhaust particles (DEPs), or aluminum oxide nanoparticles (Al₂O₃ NPs) were explored by microarray to reveal the lncRNA-microRNA-mRNA network participating in the malignant transformation of HBE cells following long-term PM_2.5 exposure. The results showed that lncRNA SOX2 overlapping transcript (SOX2-OT) was significantly induced in HBE cells exposed to PM_2.5, DEPs, or Al₂O₃ NPs, acting as a sponge to microRNA-345-5p, which subsequently increased the expression levels of epidermal growth factor receptor (EGFR). EGFR is a therapeutic target in non-small cell lung cancer. Here, we found that SOX2-OT is an upstream trigger of EGFR in HBE cells during long-term PM_2.5 exposure. Importantly, SOX2-OT knockdown effectively reduced the colony formation and migration capacities of HBE cells, compared to the wild type control. Collectively, SOX2-OT/microRNA-345-5p/EGFR is a ceRNA mechanism underlying the malignant transformation of bronchial epithelia exposed to PM_2.5, which improves our understanding of the association between ambient PM_2.5 exposure and the development of lung cancer.