Effects of short-term exposure to particulate matter air pollution on cognitive performance

Influence of meteorological conditions on the variability of indoor and outdoor particulate matter concentrations in a selected Polish health resort

The article evaluates air pollution by particulate matter (PM) in indoor and outdoor air in one of the Polish health resorts, where children and adults with respiratory diseases are treated. The highest indoor PM concentrations were recorded during the winter season. Therefore, the maximum average daily concentration values in indoor air for the PM10, PM2.5, and PM1 fractions were 50, 42 and 23 µg/m3, respectively. In the case of outdoor air, the highest average daily concentrations of PM2.5 reached a value of 40 µg/m3. The analyses and backward trajectories of episodes of high PM concentrations showed the impact of supra-regional sources and the influx of pollutants from North Africa on the variability of PM concentrations. The correlation between selected meteorological parameters and PM concentrations shows the relationship between PM concentrations and wind speed. For example, the correlation coefficients between PM1(I) and PM1(O) concentrations and wind speed were - 0.8 and - 0.7 respectively. These factors determined episodes of high PM concentrations during winter periods in the outdoor air, which were then transferred to the indoor air. Elevated concentrations in indoor air during summer were also influenced by chimney/gravity ventilation and the appearance of reverse chimney effect.

HIPTox-Hazard Identification Platform to Assess the Health Impacts from Indoor and Outdoor Air Pollutant Exposures, through Mechanistic Toxicology: A Single-Centre Double-Blind Human Exposure Trial Protocol

Over the past decade, our understanding of the impact of air pollution on short- and long-term population health has advanced considerably, focusing on adverse effects on cardiovascular and respiratory systems. There is, however, increasing evidence that air pollution exposures affect cognitive function, particularly in susceptible groups. Our study seeks to assess and hazard rank the cognitive effects of prevalent indoor and outdoor pollutants through a single-centre investigation on the cognitive functioning of healthy human volunteers aged 50 and above with a familial predisposition to dementia. Participants will all undertake five sequential controlled exposures. The sources of the air pollution exposures are wood smoke, diesel exhaust, cleaning products, and cooking emissions, with clean air serving as the control. Pre- and post-exposure spirometry, nasal lavage, blood sampling, and cognitive assessments will be performed. Repeated testing pre and post exposure to controlled levels of pollutants will allow for the identification of acute changes in functioning as well as the detection of peripheral markers of neuroinflammation and neuronal toxicity. This comprehensive approach enables the identification of the most hazardous components in indoor and outdoor air pollutants and further understanding of the pathways contributing to neurodegenerative diseases. The results of this project have the potential to facilitate greater refinement in policy, emphasizing health-relevant pollutants and providing details to aid mitigation against pollutant-associated health risks.

Particulate Matter Induces Oxidative Stress and Ferroptosis in Human Lung Epithelial Cells

Numerous toxicological studies have highlighted the association between urban particulate matter (PM) and increased respiratory infections and lung diseases. The adverse impact on the lungs is directly linked to the complex composition of particulate matter, initiating reactive oxygen species (ROS) production and consequent lipid peroxidation. Excessive ROS, particularly within mitochondria, can destroy subcellular organelles through various pathways. In this study, we confirmed the induction of ferroptosis, an iron-dependent cell death, upon exposure to an urban PM using RT-qPCR and signaling pathway analysis. We used KRISS CRM 109-02-004, the certified reference material for the analysis of particulate matter, produced by the Korea Research Institute of Standards and Science (KRISS). To validate that ferroptosis causes lung endothelial toxicity, we assessed intracellular mitochondrial potential, ROS overproduction, lipid peroxidation, and specific ferroptosis biomarkers. Following exposure to the urban PM, a significant increase in ROS generation and a decrease in mitochondrial potential were observed. Furthermore, it induced hallmarks of ferroptosis, including the accumulation of lipid peroxidation, the loss of antioxidant defenses, and cellular iron accumulation. In addition, the occurrence of oxidative stress as a key feature of ferroptosis was confirmed by increased expression levels of specific oxidative stress markers such as NQO1, CYP1B1, FTH1, SOD2, and NRF. Finally, a significant increase in key ferroptosis markers was observed, including xCT/SLC7A11, NQO1, TRIM16, HMOX-1, FTL, FTH1, CYP1B1, CHAC1, and GPX4. This provides evidence that elevated ROS levels induce oxidative stress, which ultimately triggers ferroptosis. In conclusion, our results show that the urban PM, KRISS CRM, induces cellular and mitochondrial ROS production, leading to oxidative stress and subsequent ferroptosis. These results suggest that it may induce ferroptosis through ROS generation and may offer potential strategies for the treatment of lung diseases.

Air pollution and motor vehicle collisions in New York city

Road traffic accidents are a pervasive feature of everyday life, killing 36,500 people, injuring 4.5 million and, overall, generating costs to the American society of $340 billion in 2019. Understanding the underlying factors can improve the design of prevention strategies. We use all road traffic collisions in New York City between 2013 and 2021 (N = 1,269,600) and match each individual collision to the nearest weather and air pollution station. Our study uses highly disaggregated data using an hourly frequency of collisions at a fine spatial level incorporating various air pollutants and weather factors. We employ an instrumental variable approach using temperature inversions to provide exogenous variation in air pollution addressing endogeneity and measurement error concerns. We find that higher concentrations of carbon monoxide (CO) and sulfur dioxide (SO2) increase the number of collisions but leave the severity (persons injured or killed) unaffected. Part of this can be explained by the effect of air pollutants on aggressive behavior: CO (p < .05) and SO2 (p < .01) increase the number of collisions caused by aggressive driving. Interestingly, this channel is only present in male drivers. Our results provide additional evidence that air pollution not only adversely affects health, but also has "non-health" related effects which are costly for the society.

Particulate matter exposure and neurodegenerative diseases: A comprehensive update on toxicity and mechanisms

Exposure to particulate matter (PM) has been associated with a range of health impacts, including neurological abnormalities that affect neurodevelopment, neuroplasticity, and behavior. Recently, there has been growing interest in investigating the possible relationship between PM exposure and the onset and progression of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. However, the precise mechanism by which PM affects neurodegeneration is still unclear, even though several epidemiological and animal model studies have provided mechanistic insights. This article presents a review of the current research on the neurotoxicity of PM and its impact on neurodegenerative diseases. This review summarizes findings from epidemiological and animal model studies collected through searches in Google Scholar, PubMed, Web of Science, and Scopus. This review paper also discusses the reported effects of PM exposure on the central nervous system and highlights research gaps and future directions. The information presented in this review may inform public health policies aimed at reducing PM exposure and may contribute to the development of new treatments for neurodegenerative diseases. Further mechanistic and therapeutic research will be needed to fully understand the relationship between PM exposure and neurodegenerative diseases.

Spatial Distribution of PM2.5 Mass and Number Concentrations in Paris (France) from the Pollutrack Network of Mobile Sensors during 2018-2022

The presence of particulate matter smaller than 2.5 µm in diameter (PM2.5) in ambient air has a direct pejorative effect on human health. It is thus necessary to monitor the urban PM2.5 values with high spatial resolution to better evaluate the different exposure levels that the population encounters daily. The Pollutrack network of optical mobile particle counters on the roofs of hundreds of vehicles in Paris was used to produce maps with a 1 km2 resolution (108 squares to cover the Paris surface). The study was conducted during the 2018-2022 period, showing temporal variability due to different weather conditions. When averaging all the data, the highest air pollution was found along the Paris motorway ring. Also, the mean mass concentrations of PM2.5 pollution increased from southwest to northeast, due to the typology of the city, with the presence of canyon streets, and perhaps due to the production of secondary aerosols during the transport of airborne pollutants by the dominant winds. The number of days above the new daily threshold of 15 µg.m-3 recommended by the WHO in September 2021 varies from 3.5 to 7 months per year depending on the location in Paris. Pollutrack sensors also provide the number concentrations for particles greater than 0.5 µm. Using number concentrations of very fine particles instead of mass concentrations corresponding to the dry residue of PM2.5 is more representative of the pollutants citizens actually inhale. Some recommendations for the calibration of the sensors used to provide such number concentrations are given. Finally, the consequences of such pollution on human health are discussed.

The joint effect and hemodynamic mechanism of PA and PM2.5 exposure on cognitive function: A randomized controlled trial study

BACKGROUND

While PM2.5 has been shown to impair cognitive function, physical activity (PA) is known to enhance it. Nonetheless, considering the increased inhalation of PM2.5 during exercise, the potential of PA to counteract the detrimental effects of PM2.5, along with the underlying hemodynamic mechanisms, remains uncertain.

METHODS

We conducted a double-blinded, randomized controlled trial among healthy young adults in Beijing, China. Ninety-three participants were randomly allocated to groups experiencing different intensities of PA interventions, and either subjected to purified or unpurified air conditions. Cognitive function was measured by the Color-Word Matching Stroop task, and the hemodynamic response was measured using functional near-infrared spectroscopy during participants performed the Stroop task both before and after the intervention. Linear mixed-effect models were used to estimate the impact of PA and PM2.5 on cognitive function and hemodynamic response.

RESULTS

The reaction time for congruent and incongruent Stroop tasks improved by - 80.714 (95% CI: -136.733, -24.695) and - 105.843 (95% CI: -188.6, -23.085) milliseconds after high-intensity interval training (HIIT) intervention. PM2.5 and HIIT had interaction effects on cognition, such that every 1 μg/m3 increase in PM2.5 attenuated the benefits of HIIT on reaction time by 2.231 (95% CI: 0.523, 3.938) and 3.305 (95% CI: 0.791, 5.819) milliseconds for congruent and incongruent Stroop tasks. Moreover, we divided participants into high and low PM2.5 exposure groups based on average PM2.5 concentration (32.980 μg/m3), and found that HIIT intervention in high PM2.5 concentration led to 69.897 (95% CI: 9.317, 130.476) and 99.269 (95% CI: 10.054, 188.485) milliseconds increased in the reaction time of congruent and incongruent Stroop, compared with the control group among low PM2.5. Furthermore, we found a significant interaction effects of PM2.5 and moderate-intensity continuous training (MICT) on the middle frontal gyrus (MFG) and dorsolateral superior frontal gyrus (DLPFC). PM2.5 and HIIT had a significant interaction effect on the DLPFC.

CONCLUSIONS

HIIT improved cognitive function, but the cognitive benefits of HIIT were attenuated or even reversed under high PM2.5 exposure. The activation of the DLPFC and MFG could serve as hemodynamic mechanisms to explain the joint effect of PA and PM2.5.

Environmental violence: a tool for planetary health research

From climate change to toxic pollution and the interactive effects of multiple pollution streams, human health is under siege. Human-produced environmental risks to health and wellbeing are high and contributing to patterns of global morbidity, mortality, economic inequality, displacement, and insecurity. The implications of human-produced environmental harms to global health are complex just as are their causes. The concept of environmental violence offers a potentially robust frame for engaging this issue. We argue that a more specified and structured framework and definition of environmental violence-focusing on human-produced harms by way of pollution emissions-is both timely and beneficial for engaging the complexities of global public health. To clarify why and how this is the case, we review the literature for publications that use the term environmental violence and we subsequently propose a specific definition focused on human-produced pollution along with a framework for tracking and analysing environmental violence and its constituent components. Finally, we discuss the potential value of our framework for research and policy making regarding human health.

Correlation between air pollution and cognitive impairment among older individuals: empirical evidence from China

BACKGROUND

Little information is available regarding the impact of air pollution on cognitive impairment in older individuals in developing countries. This study empirically tested the impacts of the air quality index (AQI), air pollution intensity (quantified by the number of days of extreme air pollution in a year), and different pollutants on the cognitive abilities of older Chinese individuals.

METHODS

A panel of 28,395 participants spanning 122 cities in 2015 and 2018 was used, based on 3-year follow-up survey data from the China Health and Retirement Longitudinal Study (CHARLS) database. Data from the two phases of the CHARLS microsurvey were combined with relevant statistical data on air pollution in each region in the current year. These two surveys were used to investigate changes in basic health and macro-environmental indicators in older individuals in China, and a mean difference test was conducted. We then reduced the sample selection error by controlling for environmental migration and used two-way fixed and instrumental variable methods for endogenous treatment to avoid the estimation error caused by missing variables.

RESULTS

Air pollution had a significantly negative effect on the cognitive abilities of older individuals (odds ratio [OR]: 1.4633; 95% confidence interval [95% CI]: 1.20899-1.77116). Different pollution intensities(only AQI value is greater than 200 or more) had apparent effects on cognitive impairment, with an OR of approximately 1.0. Sulfur dioxide had significantly negative effects on cognitive ability, with OR of 1.3802 (95% CI: 1.25779-1.51451). Furthermore, air pollution impact analysis showed heterogeneous results in terms of age, sex, education, and regional economic development level. In addition, social adaptability (calculated using social participation, learning, adaptability, and social support) not only had a significant positive effect on the cognitive abilities of older individuals, but also regulated the cognitive decline caused by air pollution.

CONCLUSIONS

Air pollution affects cognitive impairment in older individuals, especially in those with lower education levels, and living in economically underdeveloped areas. This effect is synchronous and has a peak at an AQI of > 200.

Airway and systemic biomarkers of health effects after short-term exposure to indoor ultrafine particles from cooking and candles - A randomized controlled double-blind crossover study among mild asthmatic subjects

BACKGROUND

There is insufficient knowledge about the systemic health effects of exposure to fine (PM_2.5) and ultrafine particles emitted from typical indoor sources, including cooking and candlelight burning. We examined whether short-term exposure to emissions from cooking and burning candles cause inflammatory changes in young individuals with mild asthma. Thirty-six non-smoking asthmatics participated in a randomized controlled double-blind crossover study attending three exposure sessions (mean PM_2.5 µg/m³_; polycyclic aromatic hydrocarbons ng/m³): (a) air mixed with emissions from cooking (96.1; 1.1), (b) air mixed with emissions from candles (89.8; 10), and (c) clean filtered air (5.8; 1.0). Emissions were generated in an adjacent chamber and let into a full-scale exposure chamber where participants were exposed for five hours. Several biomarkers were assessed in relation to airway and systemic inflammatory changes; the primary outcomes of interest were surfactant Protein-A (SP-A) and albumin in droplets in exhaled air - novel biomarkers for changes in the surfactant composition of small airways. Secondary outcomes included cytokines in nasal lavage, cytokines, C-reactive protein (CRP), epithelial progenitor cells (EPCs), genotoxicity, gene expression related to DNA-repair, oxidative stress, and inflammation, as well as metabolites in blood. Samples were collected before exposure start, right after exposure and the next morning.

RESULTS

SP-A in droplets in exhaled air showed stable concentrations following candle exposure, while concentrations decreased following cooking and clean air exposure. Albumin in droplets in exhaled air increased following exposure to cooking and candles compared to clean air exposure, although not significant. Oxidatively damaged DNA and concentrations of some lipids and lipoproteins in the blood increased significantly following exposure to cooking. We found no or weak associations between cooking and candle exposure and systemic inflammation biomarkers including cytokines, CRP, and EPCs.

CONCLUSIONS

Cooking and candle emissions induced effects on some of the examined health-related biomarkers, while no effect was observed in others; Oxidatively damaged DNA and concentrations of lipids and lipoproteins were increased in blood after exposure to cooking, while both cooking and candle emissions slightly affected the small airways including the primary outcomes SP-A and albumin. We found only weak associations between the exposures and systemic inflammatory biomarkers. Together, the results show the existence of mild inflammation following cooking and candle exposure.

The impact of COVID-19 public health restrictions on particulate matter pollution measured by a validated low-cost sensor network in Oxford, UK

Emergency responses to the COVID-19 pandemic led to major changes in travel behaviours and economic activities with arising impacts upon urban air quality. To date, these air quality changes associated with lockdown measures have typically been assessed using limited city-level regulatory monitoring data, however, low-cost air quality sensors provide capabilities to assess changes across multiple locations at higher spatial-temporal resolution, thereby generating insights relevant for future air quality interventions. The aim of this study was to utilise high-spatial resolution air quality information utilising data arising from a validated (using a random forest field calibration) network of 15 low-cost air quality sensors within Oxford, UK to monitor the impacts of multiple COVID-19 public heath restrictions upon particulate matter concentrations (PM₁₀, PM_2.5) from January 2020 to September 2021. Measurements of PM₁₀ and PM_2.5 particle size fractions both within and between site locations are compared to a pre-pandemic related public health restrictions baseline. While average peak concentrations of PM₁₀ and PM_2.5 were reduced by 9-10 μg/m³ below typical peak levels experienced in recent years, mean daily PM₁₀ and PM_2.5 concentrations were only ∼1 μg/m³ lower and there was marked temporal (as restrictions were added and removed) and spatial variability (across the 15-sensor network) in these observations. Across the 15-sensor network we observed a small local impact from traffic related emission sources upon particle concentrations near traffic-oriented sensors with higher average and peak concentrations as well as greater dynamic range, compared to more intermediate and background orientated sensor locations. The greater dynamic range in concentrations is indicative of exposure to more variable emission sources, such as road transport emissions. Our findings highlight the great potential for low-cost sensor technology to identify highly localised changes in pollutant concentrations as a consequence of changes in behaviour (in this case influenced by COVID-19 restrictions), generating insights into non-traffic contributions to PM emissions in this setting. It is evident that additional non-traffic related measures would be required in Oxford to reduce the PM₁₀ and PM_2.5 levels to within WHO health-based guidelines and to achieve compliance with PM_2.5 targets developed under the Environment Act 2021.

Lifetime air pollution exposure, cognitive deficits, and brain imaging outcomes: A systematic review

As the amount of air pollution and human exposure has increased, the effects on human health have become an important public health issue. A field of growing interest is how air pollution exposure affects brain structure and function underlying cognitive deficits and if structural and connectivity changes mediate the relationship between the two. We conducted a systematic review to examine the literature on air pollution, brain structure and connectivity, and cognition studies. Eleven studies matched our inclusion criteria and were included in the qualitative analysis. Results suggest significant associations between air pollution and decreased volumes of specific brain structures, cortical thickness and surface area such as in the prefrontal cortex and temporal lobe, as well as the weakening of functional connectivity pathways, largely the Default Mode (DMN) and Frontal Parietal (FPN) networks, as detected by fMRI. Associations between air pollution and cognitive outcomes were found in most of the studies (n = 9), though some studies showed stronger associations than others. For children & adolescents, these deficiencies largely involved heavy reasoning, problem solving, and logic. For young and middle-aged adults, the associations were mostly seen for executive function and visuospatial cognitive domains. To our knowledge, this is the first systematic review to consolidate findings on the associations among air pollution, brain structure, and cognitive function. In the future, it will be important to conduct further longitudinal studies that follow children who have been exposed at a young age and examine associations with brain structure and cognition throughout adulthood.

Monitoring and apportioning sources of indoor air quality using low-cost particulate matter sensors

Air quality is one of the most important factors in public health. While outdoor air quality is widely studied, the indoor environment has been less scrutinised, even though time spent indoors is typically much greater than outdoors. The emergence of low-cost sensors can help assess indoor air quality. This study provides a new methodology, utilizing low-cost sensors and source apportionment techniques, to understand the relative importance of indoor and outdoor air pollution sources upon indoor air quality. The methodology is tested with three sensors placed in different rooms inside an exemplar house (bedroom, kitchen and office) and one outdoors. When the family was present, the bedroom had the highest average concentrations for PM_2.5 and PM₁₀ (3.9 ± 6.8 ug/m³ and 9.6 ± 12.7 μg/m³ respectively), due to the activities undertaken there and the presence of softer furniture and carpeting. The kitchen, while presenting the lowest PM concentrations for both size ranges (2.8 ± 5.9 ug/m³ and 4.2 ± 6.9 μg/m³ respectively), presented the highest PM spikes, especially during cooking times. Increased ventilation in the office resulted in the highest PM₁ concentration (1.6 ± 1.9 μg/m³), highlighting the strong effect of infiltration of outdoor air for the smallest particles. Source apportionment, via positive matrix factorisation (PMF), showed that up to 95 % of the PM₁ was found to be of outdoor sources in all the rooms. This effect was reduced as particle size increased, with outdoor sources contributing >65 % of the PM_2.5, and up to 50 % of the PM₁₀, depending on the room studied. The new approach to elucidate the contributions of different sources to total indoor air pollution exposure, described in this paper, is easily scalable and translatable to different indoor locations.

Urban precarity and youth mental health: An interpretive scoping review of emerging approaches

Circumstances of living are key to shaping emotional and affective experiences, long term health, wellbeing and opportunities. In an era characterised by rapid urbanisation across the majority of the world, there is increasing interest in the interaction between mental health and urban environments, but insufficient attention is paid to how mental health is situated in space and time. Socio-economic inequalities are prevalent in many urban environments globally, making conditions of living highly precarious for some social groups including young people. There remains a large volume of unmet mental health service needs, and young people are impacted by uncertain economic futures. The purpose of this scoping review is to develop an interdisciplinary and globally-informed understanding of the urban conditions which affect youth mental health across a range of scales, and to identify protective factors which can promote better youth mental health. We seek to broaden the scope of urban mental health research beyond the physical features of urban environments to develop an interpretive framework based on perspectives shared by young people. We illustrate how concepts from social theory can be used as an integrative framework to emphasise both young people's lived experiences and the wider cultural and political dynamics of urban mental health.

Randomized Cross-Over Study of In-Vehicle Cabin Air Filtration, Air Pollution Exposure, and Acute Changes to Heart Rate Variability, Saliva Cortisol, and Cognitive Function

To determine how traffic-related air pollution (TRAP) exposures affect commuter health, and whether cabin air filtration (CAF) can mitigate exposures, we conducted a cross-over study of 48 adults exposed to TRAP during two commutes with and without CAF. Measurements included particulate air pollutants (PM_2.5, black carbon [BC], ultrafine particles [UFPs]), volatile organic compounds, and nitrogen dioxide. We measured participants' heart rate variability (HRV), saliva cortisol, and cognitive function. On average, CAF reduced concentrations of UFPs by 26,232 (95%CI: 11,734, 40,730) n/cm³, PM_2.5 by 6 (95%CI: 5, 8) μg/m³, and BC by 1348 (95%CI: 1042, 1654) ng/m³, or 28, 30, and 32%, respectively. Each IQR increase in PM_2.5 was associated with a 28% (95%CI: 2, 60) increase in high-frequency power HRV at the end of the commute and a 22% (95%CI: 7, 39) increase 45 min afterward. IQR increases in UFPs were associated with increased saliva cortisol in women during the commute (18% [95%CI: 0, 40]). IQR increases in UFPs were associated with strong switching costs (19% [95%CI: 2, 39]), indicating a reduced capacity for multitasking, and PM_2.5 was associated with increased reaction latency, indicating slower responses (5% [95%CI: 1, 10]). CAF can reduce particulate exposures by almost a third.

Aerosol physicochemical determinants of carbon black and ozone inhalation co-exposure induced pulmonary toxicity

Air pollution accounts for more than 7 million premature deaths worldwide. Using ultrafine carbon black (CB) and ozone (O3) as a model for an environmental co-exposure scenario, the dose response relationships in acute pulmonary injury and inflammation were determined by generating, characterizing, and comparing stable concentrations of CB aerosols (2.5, 5.0, 10.0 mg/m3), O3 (0.5, 1.0, 2.0 ppm) with mixture CB + O3 (2.5 + 0.5, 5.0 + 1.0, 10.0 + 2.0). C57BL6 male mice were exposed for 3 h by whole body inhalation and acute toxicity determined after 24 h. CB itself did not cause any alteration, however, a dose response in pulmonary injury/inflammation was observed with O3 and CB + O3. This increase in response with mixtures was not dependent on the uptake but was due to enhanced reactivity of the particles. Benchmark dose modeling showed several-fold increase in potency with CB + O3 compared with CB or O3 alone. Principal component analysis provided insight into response relationships between various doses and treatments. There was a significant correlation in lung responses with charge-based size distribution, total/alveolar deposition, oxidant generation, and antioxidant depletion potential. Lung tissue gene/protein response demonstrated distinct patterns that are better predicted by either particle dose/aerosol responses (interleukin-1β, keratinocyte chemoattractant, transforming growth factor beta) or particle reactivity (thymic stromal lymphopoietin, interleukin-13, interleukin-6). Hierarchical clustering showed a distinct signature with high dose and a similarity in mRNA expression pattern of low and medium doses of CB + O3. In conclusion, we demonstrate that the biological outcomes from CB + O3 co-exposure are significantly greater than individual exposures over a range of aerosol concentrations and aerosol characteristics can predict biological outcome.

Air Quality Is Predictive of Mistakes in Professional Baseball and American Football

Air quality is a growing environmental concern that has implications for human physical and mental health. While air pollution has been linked to cognitive disease progression and declines in overall health, the impacts of air quality on athletic performance have not been extensively investigated. Much of the previous research focused on endurance sports indicates that air quality negatively impacts athletic performance; however, the effects of air quality on non-endurance elite team performance remains largely unknown. The purpose of this study was to examine the impact of air quality on errors committed by Major League Baseball (MLB) teams, interceptions thrown by quarterbacks in the National Football League (NFL), and overall quarterback performance in the NFL. Linear regression analysis was used to determine the impact of the median air quality index (AQI) of counties with MLB and NFL teams on errors, interceptions, and overall quarterback performance of players on those MLB and NFL teams. AQI was a significant positive predictor of errors and interceptions, indicating increased errors and interceptions with decreased air quality. Similarly, quarterback performance was significantly reduced for quarterbacks from teams in counties with worse air quality. These findings suggest that air quality has a significant impact on performance in the MLB and NFL, indicating impairments in physical and cognitive performance in professional athletes when competing in areas with poorer air quality. Hence, it is likely that air quality impacts athletic performance in numerous sports that have not yet been investigated.

The unbalanced trade-off between pollution exposure and energy consumption induced by averting behaviors

Behavioral responses to environmental risks create gains and losses. We use high-frequency datasets to elucidate such behavior responses against air pollution and find a "double-peaked" time pattern in reducing outdoor exposure and in increasing electricity consumption. Despite that one standard deviation increase in the Air Quality Index induces 2% less outdoor population and 6% more household electricity consumption at peak, most responses fail to match with the intra-day pollution peaks, implying ineffective exposure avoidance. We find an unbalanced trade-off between health benefits and energy co-damages. The behavior-induced change in annual residential power consumption (+1.01% to +1.20%) is estimated to be 20 times more than that in the population-based exposure (-0.02% to -0.05%), and generates 0.13-0.15 million more metric tons of citywide carbon emissions. Our results imply that by targeting peak pollution periods, policies can shrink the trade-off imbalance and achieve mutual improvements in exposure reduction and energy conservation.

Mitigating the impact of air pollution on dementia and brain health: Setting the policy agenda

BACKGROUND

Emerging research suggests exposure to high levels of air pollution at critical points in the life-course is detrimental to brain health, including cognitive decline and dementia. Social determinants play a significant role, including socio-economic deprivation, environmental factors and heightened health and social inequalities. Policies have been proposed more generally, but their benefits for brain health have yet to be fully explored.

OBJECTIVE AND METHODS

Over the course of two years, we worked as a consortium of 20+ academics in a participatory and consensus method to develop the first policy agenda for mitigating air pollution's impact on brain health and dementia, including an umbrella review and engaging 11 stakeholder organisations.

RESULTS

We identified three policy domains and 14 priority areas. Research and Funding included: (1) embracing a complexities of place approach that (2) highlights vulnerable populations; (3) details the impact of ambient PM_2.5 on brain health, including current and historical high-resolution exposure models; (4) emphasises the importance of indoor air pollution; (5) catalogues the multiple pathways to disease for brain health and dementia, including those most at risk; (6) embraces a life course perspective; and (7) radically rethinks funding. Education and Awareness included: (8) making this unrecognised public health issue known; (9) developing educational products; (10) attaching air pollution and brain health to existing strategies and campaigns; and (11) providing publicly available monitoring, assessment and screening tools. Policy Evaluation included: (12) conducting complex systems evaluation; (13) engaging in co-production; and (14) evaluating air quality policies for their brain health benefits.

CONCLUSION

Given the pressing issues of brain health, dementia and air pollution, setting a policy agenda is crucial. Policy needs to be matched by scientific evidence and appropriate guidelines, including bespoke strategies to optimise impact and mitigate unintended consequences. The agenda provided here is the first step toward such a plan.

Short-term PM2.5 exposure and cognitive function: Association and neurophysiological mechanisms

BACKGROUND

Although converging evidence has demonstrated that exposure to fine particulate matter (PM_2.5) caused adverse effects on brain structure and cognitive function, the association between the short-term exposure to PM_2.5 and cognition dysfunction remained underexplored, especially possible neurophysiological mechanisms.

METHODS

We conducted a longitudinal observational study with four repeated measurement sessions among 90 young adults from September 2020 to June 2021. During each measurement session, we measured participants' personal-level air pollution exposure for one week with portable monitors, followed by executive function assessment and electrophysiological signal recording at an assessment center. Standard Stroop color-word test was used accompanied with electroencephalogram (EEG) recording to assess performance on executive function. We used linear mixed-effect model with lagged values of PM_2.5 levels to analyze the association between PM_2.5 exposure and changes in executive function, and mediation analysis to investigate mediation effect by EEG signal.

RESULTS

Adjusted mixed-effect models demonstrated that elevated PM_2.5 exposure three days prior to cognitive assessment (lag-3) was associated with (1) declined performance in both congruent and incongruent tasks in Stroop test, (2) reduced lower and upper alpha event-related desynchronization (ERD) during 500-1000 ms after stimuli, both indicating impaired executive control. Lower and upper alpha ERD also mediated observed associations between short-term PM_2.5 exposure and executive function. No significant associations were found between short-term PM_2.5 exposure or aperiodic exponents in tonic and phasic states, or periodic alpha oscillations in tonic state.

CONCLUSION

Our results provided evidence that short-term PM_2.5 exposure was associated with executive dysfunction. Reduced alpha ERD was likely to be the underlying pathway through which PM_2.5 induced adverse effects on neuron activities during cognitive tasks.

Deaths Attributable to Indoor PM2.5 in Urban China When Outdoor Air Meets 2021 WHO Air Quality Guidelines

The World Health Organization reduced the recommended level of annual mean PM_2.5 concentrations to 5 μg/m³ in 2021. Previously, the guideline was geared toward ambient air pollution, and now it explicitly applies to indoor air pollution. However, the disease burden attributed to different indoor emission sources has been overlooked, particularly in urban areas. Our objective was to estimate the mortality attributable to indoor PM_2.5 in urban areas in China. Our model estimated 711 thousand (584-823) deaths and 2.75 trillion (2.26-3.19) CNY economic losses attributable to PM_2.5 in urban China in 2019, in which indoor sources contributed 394 thousand (323-457) deaths and 1.53 trillion (1.25-1.77) CNY losses. There would still be 536 thousand (427-638) PM_2.5-attributable deaths and 2.07 trillion (1.65-2.47) CNY losses each year when the outdoor PM_2.5 is 5 μg/m³, of which 485 thousand (386-578) deaths and 1.87 trillion (1.49-2.23) CNY are attributable to indoor sources. Despite cleaner outdoor air and no solid fuels being used, considerable health hazards and economic losses are attributable to indoor PM_2.5. Measures to reduce PM_2.5 exposure in humans from both indoor and outdoor sources are required to achieve a substantial reduction in deaths.

Enhanced Ambient Sensing Environment-A New Method for Calibrating Low-Cost Gas Sensors

Accurate calibration of low-cost gas sensors is, at present, a time consuming and difficult process. Laboratory calibration and field calibration methods are currently used, but laboratory calibration is generally discounted due to poor transferability, and field methods requiring several weeks are standard. The Enhanced Ambient Sensing Environment (EASE) method described in this article, is a hybrid of the two, combining the advantages of a laboratory calibration with the increased accuracy of a field calibration. It involves calibrating sensors inside a duct, drawing in ambient air with similar properties to the site where the sensors will operate, but with the added feature of being able to artificially increases or decrease pollutant levels, thus condensing the calibration period required. Calibration of both metal-oxide (MOx) and electrochemical (EC) gas sensors for the measurement of NO₂ and O₃ (0-120 ppb) were conducted in EASE, laboratory and field environments, and validated in field environments. The EC sensors performed marginally better than MOx sensors for NO₂ measurement and sensor performance was similar for O₃ measurement, but the EC sensor nodes had less node inter-node variability and were more robust. For both gasses and sensor types the EASE calibration outperformed the laboratory calibration, and performed similarly to or better than the field calibration, whilst requiring a fraction of the time.

Importance of Punctual Monitoring to Evaluate the Health Effects of Airborne Particulate Matter

Particulate matter (PM) pollution is one of the major public health problems worldwide, given the high mortality attributable to exposure to PM pollution and the high pathogenicity that is found above all in the respiratory, cardiovascular, and neurological systems. The main sources of PM pollution are the daily use of fuels (wood, coal, organic residues) in appliances without emissions abatement systems, industrial emissions, and vehicular traffic. This review aims to investigate the causes of PM pollution and classify the different types of dust based on their size. The health effects of exposure to PM will also be discussed. Particular attention is paid to the measurement method, which is unsuitable in the risk assessment process, as the evaluation of the average PM compared to the evaluation of PM with punctual monitoring significantly underestimates the health risk induced by the achievement of high PM values, even for limited periods of time.

Use of candles and risk of cardiovascular and respiratory events in a Danish cohort study

Burning candles at home emit small particles and gases that pollute indoor air. Exposure to fine particles in outdoor air has been convincingly linked to cardiovascular and respiratory events, while the associations with fine and ultrafine particles from candle burning remain unexplored. We examined the association between the use of candles and incident cardiovascular and respiratory events. We collected data on 6757 participants of the Copenhagen Aging and Midlife Biobank cohort recruited in 2009 and followed them up for the first hospital contact for incident cardiovascular and respiratory events until 2018. We investigated an association between the self-reported frequency of candle use in wintertime and cardiovascular and respiratory events, using Cox regression models adjusting for potential confounders. During follow-up, 1462 and 834 were admitted for cardiovascular and respiratory events, respectively. We found null associations between candle use and a hospital contact due to cardiovascular and respiratory events, with hazard ratios (HRs) and 95% confidence intervals (CI) of 0.97 (95% CI: 0.84, 1.11) and 0.98 (95% CI: 0.81, 1.18), respectively, among those using candles >4 times/week compared with <1 time/week. For cause-specific cardiovascular diseases, HRs were 1.10 (95% CI: 0.85, 1.43) for ischemic heart disease and 1.18 (95% CI: 0.77, 1.81) for myocardial infarction. For chronic obstructive pulmonary disease, HR was 1.26 (95% CI: 0.81, 1.97). We found no statistically significant associations between candle use and the risk of cardiovascular and respiratory events. Studies with improved exposure assessments are warranted.

Decoding Physical and Cognitive Impacts of Particulate Matter Concentrations at Ultra-Fine Scales

The human body is an incredible and complex sensing system. Environmental factors trigger a wide range of automatic neurophysiological responses. Biometric sensors can capture these responses in real time, providing clues about the underlying biophysical mechanisms. In this prototype study, we demonstrate an experimental paradigm to holistically capture and evaluate the interactions between an environmental context and physiological markers of an individual operating that environment. A cyclist equipped with a biometric sensing suite is followed by an environmental survey vehicle during outdoor bike rides. The interactions between environment and physiology are then evaluated though the development of empirical machine learning models, which estimate particulate matter concentrations from biometric variables alone. Here, we show biometric variables can be used to accurately estimate particulate matter concentrations at ultra-fine spatial scales with high fidelity (r2 = 0.91) and that smaller particles are better estimated than larger ones. Inferring environmental conditions solely from biometric measurements allows us to disentangle key interactions between the environment and the body. This work sets the stage for future investigations of these interactions for a larger number of factors, e.g., black carbon, CO2, NO/NO2/NOx, and ozone. By tapping into our body's 'built-in' sensing abilities, we can gain insights into how our environment influences our physical health and cognitive performance.

Short-Term Exposure to Wildfire Smoke and PM2.5 and Cognitive Performance in a Brain-Training Game: A Longitudinal Study of U.S. Adults

BACKGROUND

There is increasing evidence that long-term exposure to fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] may adversely impact cognitive performance. Wildfire smoke is one of the biggest sources of PM2.5 and concentrations are likely to increase under climate change. However, little is known about how short-term exposure impacts cognitive function.

OBJECTIVES

We aimed to evaluate the associations between daily and subdaily (hourly) PM2.5 and wildfire smoke exposure and cognitive performance in adults.

METHODS

Scores from 20 plays of an attention-oriented brain-training game were obtained for 10,228 adults in the United States (U.S.). We estimated daily and hourly PM2.5 exposure through a data fusion of observations from multiple monitoring networks. Daily smoke exposure in the western U.S. was obtained from satellite-derived estimates of smoke plume density. We used a longitudinal repeated measures design with linear mixed effects models to test for associations between short-term exposure and attention score. Results were also stratified by age, gender, user behavior, and region.

RESULTS

Daily and subdaily PM2.5 were negatively associated with attention score. A 10 μg/m3 increase in PM2.5 in the 3 h prior to gameplay was associated with a 21.0 [95% confidence interval (CI): 3.3, 38.7]-point decrease in score. PM2.5 exposure over 20 plays accounted for an estimated average 3.7% (95% CI: 0.7%, 6.7%) reduction in final score. Associations were more pronounced in the wildfire-impacted western U.S. Medium and heavy smoke density were also negatively associated with score. Heavy smoke density the day prior to gameplay was associated with a 117.0 (95% CI: 1.7, 232.3)-point decrease in score relative to no smoke. Although differences between subgroups were not statistically significant, associations were most pronounced for younger (18-29 y), older (≥70y), habitual, and male users.

DISCUSSION

Our results indicate that PM2.5 and wildfire smoke were associated with reduced attention in adults within hours and days of exposure, but further research is needed to elucidate these relationships. https://doi.org/10.1289/EHP10498.

Short-term NO2 exposure and cognitive and mental health: A panel study based on a citizen science project in Barcelona, Spain

BACKGROUND

The association between short-term exposure to air pollution and cognitive and mental health has not been thoroughly investigated so far.

OBJECTIVES

We conducted a panel study co-designed with citizens to assess whether air pollution can affect attention, perceived stress, mood and sleep quality.

METHODS

From September 2020 to March 2021, we followed 288 adults (mean age = 37.9 years; standard deviation = 12.1 years) for 14 days in Barcelona, Spain. Two tasks were self-administered daily through a mobile application: the Stroop color-word test to assess attention performance and a set of 0-to-10 rating scale questions to evaluate perceived stress, well-being, energy and sleep quality. From the Stroop test, three outcomes related to selective attention were calculated and z-score-transformed: response time, cognitive throughput and inhibitory control. Air pollution was assessed using the mean nitrogen dioxide (NO₂) concentrations (mean of all Barcelona monitoring stations or using location data) 12 and 24 h before the tasks were completed. We applied linear regression with random effects by participant to estimate intra-individual associations, controlling for day of the week and time-varying factors such as alcohol consumption and physical activity.

RESULTS

Based on 2,457 repeated attention test performances, an increase of 30 μg/m³ exposure to NO₂ 12 h was associated with lower cognitive throughput (beta = -0.08, 95% CI: -0.15, -0.01) and higher response time (beta = 0.07, 95% CI: 0.01, 0.14) (increase inattentiveness). Moreover, an increase of 30 μg/m³ exposure to NO₂ 12 h was associated with higher self-perceived stress (beta = 0.44, 95% CI: 0.13, 0.77). We did not find statistically significant associations with inhibitory control and subjective well-being.

CONCLUSIONS

Our findings suggest that short-term exposure to air pollution could have adverse effects on attention performance and perceived stress in adults.

Differential effects of Urban Particulate Matter on BV2 microglial-like and C17.2 neural stem/precursor cells

Air pollution affects the majority of the world's population and has been linked to over 7 million premature deaths per year. Exposure to particulate matter (PM) contained within air pollution is associated with cardiovascular, respiratory and neurological ill health. There is increasing evidence that exposure to air pollution in utero and in early childhood is associated with altered brain development. However, the underlying mechanisms for impaired brain development are not clear. While oxidative stress and neuroinflammation are documented consequences of PM exposure, cell-specific mechanisms that may be triggered in response to air pollution exposure are less well defined. Here we assess the effect of urban (U)PM exposure on two different cell types, microglial-like BV2 cells and neural stem / precursor-like C17.2 cells. We found that, contrary to expectations, immature C17.2 cells were more resistant to PM-mediated oxidative stress and cell death than BV2 cells. PM exposure resulted in decreased mitochondrial health and increased mitochondrial ROS in BV2 cells which could be prevented by mitoTEMPO antioxidant treatment. Our data suggest that not only is mitochondrial dysfunction a key trigger in PM-mediated cytotoxicity, but that such deleterious effects may also depend on cell type and maturity.

Acute health effects from exposure to indoor ultrafine particles-A randomized controlled crossover study among young mild asthmatics

Particulate matter is linked to adverse health effects, however, little is known about health effects of particles emitted from typical indoor sources. We examined acute health effects of short-term exposure to emissions from cooking and candles among asthmatics. In a randomized controlled double-blinded crossover study, 36 young non-smoking asthmatics attended three exposure sessions lasting 5 h: (a) air mixed with emissions from cooking (fine particle mass concentration): (PM_2.5 : 96.1 μg/m³ ), (b) air mixed with emissions from candles (PM_2.5 : 89.8 μg/m³ ), and c) clean filtered air (PM_2.5 : 5.8 μg/m³ ). Health effects (spirometry, fractional exhaled Nitric Oxide [FeNO], nasal volume and self-reported symptoms) were evaluated before exposure start, then 5 and 24 h after. During exposures volatile organic compounds (VOCs), particle size distributions, number concentrations and optical properties were measured. Generally, no statistically significant changes were observed in spirometry, FeNO, or nasal volume comparing cooking and candle exposures to clean air. In males, nasal volume and FeNO decreased after exposure to cooking and candles, respectively. Participants reported additional and more pronounced symptoms during exposure to cooking and candles compared to clean air. The results indicate that emissions from cooking and candles exert mild inflammation in asthmatic males and decrease comfort among asthmatic males and females.

Emissions of soot, PAHs, ultrafine particles, NOx, and other health relevant compounds from stressed burning of candles in indoor air

Burning candles release a variety of pollutants to indoor air, some of which are of concern for human health. We studied emissions of particles and gases from the stressed burning of five types of pillar candles with different wax and wick compositions. The stressed burning was introduced by controlled fluctuating air velocities in a 21.6 m³ laboratory chamber. The aerosol physicochemical properties were measured both in well-mixed chamber air and directly above the candle flame with online and offline techniques. All candles showed different emission profiles over time with high repeatability among replicates. The particle mass emissions from stressed burning for all candle types were dominated by soot (black carbon; BC). The wax and wick composition strongly influenced emissions of BC, PM_2.5 , and particle-phase polycyclic aromatic hydrocarbons (PAHs), and to lower degree ultrafine particles, inorganic and organic carbon fraction of PM, but did not influence NO_x , formaldehyde, and gas-phase PAHs. Measurements directly above the flame showed empirical evidence of short-lived strong emission peaks of soot particles. The results show the importance of including the entire burn time of candles in exposure assessments, as their emissions can vary strongly over time. Preventing stressed burning of candles can reduce exposure to pollutants in indoor air.

Long-term exposure to fine particulate matter, lung function and cognitive performance: A prospective Dutch cohort study on the underlying routes

BACKGROUND

Exposure to fine particulate matter and black carbon is related to cognitive impairment and poor lung function, but less is known about the routes taken by different types of air pollutants to affect cognition.

OBJECTIVES

We tested two possible routes of fine particulate matter (PM_2.5) and black carbon (BC) in impairing cognition, and evaluated their importance: a direct route over the olfactory nerve or the blood stream, and an indirect route over the lung.

METHODS

We used longitudinal observational data for 49,705 people aged 18+ from 2006 to 2015 from the Dutch Lifelines cohort study. By linking current home addresses to air pollution exposure data from ELAPSE in 2010, long-term average exposure to PM_2.5 and BC was assessed. Lung function was measured by spirometry and Global Initiative (GLI) z-scores of forced expiratory volume in 1s (FEV₁) and forced vital capacity (FVC) were calculated. Cognitive performance was measured by cognitive processing time (CPT) assessed by the Cogstate Brief Battery. Linear structural equation modeling was performed to test direct/indirect associations.

RESULTS

Higher exposure to PM_2.5 but not BC was related to higher CPT and slower cognitive processing speed [Total Effect PM_2.5: FEV₁ model = 8.31 × 10^-3 (95% CI: 5.71 × 10^-3, 10.91 × 10^-3), FVC model = 8.30 × 10^-3 (95% CI: 5.69 × 10^-3, 10.90 × 10^-3)]. The direct association of PM_2.5 constituted more than 97% of the total effect. Mediation by lung function was low for PM_2.5 with a mediated proportion of 1.32% (FEV₁) and 2.05% (FVC), but higher for BC (7.01% and 13.82% respectively).

DISCUSSION

Our results emphasise the importance of the lung acting as a mediator in the relationship between both exposure to PM_2.5 and BC, and cognitive performance. However, higher exposure to PM_2.5 was mainly directly associated with worse cognitive performance, which emphasises the health-relevance of fine particles due to their ability to reach vital organs directly.

Associations between Acute Exposures to PM2.5 and Carbon Dioxide Indoors and Cognitive Function in Office Workers: A Multicountry Longitudinal Prospective Observational Study

Despite evidence of the air pollution effects on cognitive function, little is known about the acute impact of indoor air pollution on cognitive function among the working-age population. We aimed to understand whether cognitive function was associated with real-time indoor concentrations of particulate matter (PM2.5) and carbon dioxide (CO2). We conducted a prospective observational longitudinal study among 302 office workers in urban commercial buildings located in six countries (China, India, Mexico, Thailand, the United States of America, and the United Kingdom). For 12 months, assessed cognitive function using the Stroop color-word test and Addition-Subtraction test (ADD) via a mobile research app. We found that higher PM2.5 and lower ventilation rates, as assessed by CO2 concentration, were associated with slower response times and reduced accuracy (fewer correct responses per minute) on the Stroop and ADD for 8 out 10 test metrics. Each interquartile (IQR) increase in PM2.5 (IQR=8.8 µg/m3) was associated with a 0.82% (95%CI: 0.42, 1.21) increase in Stroop response time, a 6.18% (95% CI: 2.08, 10.3) increase in Stroop interference time, a 0.7% (95% CI: -1.38, -0.01) decrease in Stroop throughput, and a 1.51% (95% CI: -2.65, -0.37) decrease in ADD throughput. For CO2, an IQR increase (IQR=315ppm) was associated with a 0.85% (95% CI: 0.32, 1.39) increase in Stroop response time, a 7.88% (95% CI: 2.08, 13.86) increase in Stroop interference time, a 1.32% (95% CI: -2.3, -0.38) decrease in Stroop throughput, and a 1.13% (95% CI: 0.18, 2.11) increase in ADD response time. A sensitivity analysis showed significant association between PM2.5 in four out of five cognitive test performance metrics only at levels above 12 µg/m3. Enhanced filtration and higher ventilation rates that exceed current minimum targets are essential public health strategies that may improve employee productivity.

The Diamond League athletic series: does the air quality sparkle?

Urban air pollution can have negative short- and long-term impacts on health, including cardiovascular, neurological, immune system and developmental damage. The irritant qualities of pollutants such as ozone (O₃), nitrogen dioxide (NO₂) and particulate matter (PM) can cause respiratory and cardiovascular distress, which can be heightened during physical activity and particularly so for those with respiratory conditions such as asthma. Previously, research has only examined marathon run outcomes or running under laboratory settings. This study focuses on elite 5-km athletes performing in international events at nine locations. Local meteorological and air quality data are used in conjunction with race performance metrics from the Diamond League Athletics series to determine the extent to which elite competitors are influenced during maximal sustained efforts in real-world conditions. The findings from this study suggest that local meteorological variables (temperature, wind speed and relative humidity) and air quality (ozone and particulate matter) have an impact on athletic performance. Variation between finishing times at different race locations can also be explained by the local meteorology and air quality conditions seen during races.

Global distribution and coincidence of pollution, climate impacts, and health risk in the Anthropocene

Previous research demonstrates that low-income countries face higher risks than high-income countries from toxic pollution and climate change. However, the relationship between these two risks is little explored or tested, and efforts to address the risks are often independent and uncoordinated. We argue that the global risks from toxic pollution and climate change are highly correlated and should be jointly analyzed in order to inform and better target efforts to reduce or mitigate both risks. We provide such analysis for 176 countries and found a strong (r_s = -0.798;95%CI -0.852, -0.727) and significant (p<0.0001) relationship between the distribution of climate risk and toxic pollution. We also found that inequities in pollution production, economic status, and institutional readiness are interconnected and exacerbate risk for countries already in the highest risk categories for both toxic and non-toxic (greenhouse gas) pollution. The findings have policy implications, including the use of the proposed Target assessment to decide where best to address toxic and non-toxic pollution simultaneously, based on the need to minimize human suffering and maximize return on effort.

Emissions of ultrafine particles from five types of candles during steady burn conditions

Emissions from candles are of concern for indoor air quality. In this work, five different types of pillar candles were burned under steady burn conditions in a new laboratory scale system for repeatable and controlled comparison of candle emissions (temperature ~25°C, relative humidity ~13%, O₂ >18%, air exchange rate 1.9 h^-1 ). Burn rate, particle number concentrations, mass concentrations, and mode diameters varied between candle types. Based on the results, the burning period was divided in two phases: initial (0-1 h) and stable (1-6 h). Burn rates were in the range 4.4-7.3 and 4.7-7.1 g/h during initial and stable phase, respectively. Relative particle number emissions, mode diameters, and mass concentrations were higher during the initial phase compared to the stable phase for a majority of the candles. We hypothesize that this is due to elevated emissions of wick additives upon ignition of the candle together with a slightly higher burn rate in the initial phase. Experiments at higher relative humidity (~40%) gave similar results with a tendency toward larger particle sizes at the higher relative humidity. Chemical composition with respect to inorganic salts was similar in the emitted particles (dry conditions) compared to the candlewicks, but with variations between different candles.

Climate change, environment pollution, COVID-19 pandemic and mental health

Converging data would indicate the existence of possible relationships between climate change, environmental pollution and epidemics/pandemics, such as the current one due to SARS-CoV-2 virus. Each of these phenomena has been supposed to provoke detrimental effects on mental health. Therefore, the purpose of this paper was to review the available scientific literature on these variables in order to suggest and comment on their eventual synergistic effects on mental health. The available literature report that climate change, air pollution and COVID-19 pandemic might influence mental health, with disturbances ranging from mild negative emotional responses to full-blown psychiatric conditions, specifically, anxiety and depression, stress/trauma-related disorders, and substance abuse. The most vulnerable groups include elderly, children, women, people with pre-existing health problems especially mental illnesses, subjects taking some types of medication including psychotropic drugs, individuals with low socio-economic status, and immigrants. It is evident that COVID-19 pandemic uncovers all the fragility and weakness of our ecosystem, and inability to protect ourselves from pollutants. Again, it underlines our faults and neglect towards disasters deriving from climate change or pollution, or the consequences of human activities irrespective of natural habitats and constantly increasing the probability of spillover of viruses from animals to humans. In conclusion, the psychological/psychiatric consequences of COVID-19 pandemic, that currently seem unavoidable, represent a sharp cue of our misconception and indifference towards the links between our behaviour and their influence on the "health" of our planet and of ourselves. It is time to move towards a deeper understanding of these relationships, not only for our survival, but for the maintenance of that balance among man, animals and environment at the basis of life in earth, otherwise there will be no future.

The contribution of cooking appliances and residential traffic proximity to aerosol personal exposure

PURPOSE

Indoor and outdoor factors affect personal exposure to air pollutants. Type of cooking appliance (i.e. gas, electricity), and residential location related to traffic are such factors. This research aims to investigate the effect of cooking with gas and electric appliances, as an indoor source of aerosols, and residential traffic as outdoor sources, on personal exposures to particulate matter with an aerodynamic diameter lower than 2.5 μm (PM_2.5), black carbon (BC), and ultrafine particles (UFP).

METHODS

Forty subjects were sampled for four consecutive days measuring personal exposures to three aerosol pollutants, namely PM_2.5, BC, and UFP, which were measured using personal sensors. Subjects were equally distributed into four categories according to the use of gas or electric stoves for cooking, and to residential traffic (i.e. houses located near or away from busy roads).

RESULTS/CONCLUSION

Cooking was identified as an indoor activity affecting exposure to aerosols, with mean concentrations during cooking ranging 24.7-50.0 μg/m³ (PM_2.5), 1.8-4.9 μg/m³ (BC), and 1.4 × 10⁴-4.1 × 10⁴ particles/cm³ (UFP). This study also suggest that traffic is a dominant source of exposure to BC, since people living near busy roads are exposed to higher BC concentrations than those living further away from traffic. In contrast, the contribution of indoor sources to personal exposure to PM_2.5 and UFP seems to be greater than from outdoor traffic sources. This is probably related to a combination of the type of building construction and a varying range of activities conducted indoors. It is recommended to ensure a good ventilation during cooking to minimize exposure to cooking aerosols.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40201-020-00604-7.

Short-term air pollution, cognitive performance and nonsteroidal anti-inflammatory drug use in the Veterans Affairs Normative Aging Study

Air pollution, especially the fine particulate matter (PM_2.5), may impair cognitive performance^1-3, but its short-term impact remains poorly understood. We investigated the short-term associations of PM_2.5 with the cognitive performances of 954 white males measured as the global cognitive function (GCF) and Mini-Mental State Examination (MMSE) scores, and further explored whether taking nonsteroidal anti-inflammatory drugs (NSAIDs) could modify their relationships. Higher short-term exposure to PM_2.5 demonstrated non-linear negative associations with cognitive function. Compared with the lowest quartile of the 28-day average PM_2.5 concentration, the 2^nd, 3^rd, and 4^th quartiles were associated with 0.378-, 0.376-, and 0.499-unit decreases in GCF score, 0.484-, 0.315-, and 0.414-unit decreases in MMSE score, and 69%, 45%, and 63% greater odds of low MMSE scores (≤25), respectively. Such adverse effects were attenuated among NSAIDs users compared to non-users. This study elucidates the short-term impacts of air pollution on cognition and warrants further investigations on the modifying effects of NSAIDs.

High Resolution Mapping of PM2.5 Concentrations in Paris (France) Using Mobile Pollutrack Sensors Network in 2020

There is a need for accurate monitoring of PM2.5 that adversely affects human health. Consequently, in addition to the monitoring performed by fixed microbalance instruments installed under legal obligation, we are proposing to deploy the Pollutrack network of mobile sensors within the city of Paris (France). The measurements are performed by mobile aerosol counters mounted on the roof of cars, providing a constant series of readings in the 0.3–10 µm size range that are then aggregated to identify areas of mass concentrations of pollution. The performance of the Pollutrack sensors has been established in ambient air in comparison with the microbalance measurement devices and with the Light Optical Aerosols Counter (LOAC) aerosol counter. A measurement uncertainty of about 5 µg. m−3 is obtained with absolute values from the Pollutrack measurements made at a given location. Instead of the current modelizations based on very few PM2.5 values, maps built from real measurements with a spatial resolution down to 100 m can now be produced each day for Paris, and potentially for specific times of the day, thanks to the high number of measurements achievable with the Pollutrack system (over 70,000 on weekdays). Interestingly, the global trend of PM2.5 content shows several significant pollution events in 2020 despite the COVID-19 crisis and the lockdown. The Pollutrack pollution maps recorded during different PM2.5 pollution conditions in the city frequently identified a strong spatial heterogeneity where the North and the East of Paris were more polluted than the west. These “hot spots” could be due to the city topology and its sensitivity to wind direction and intensity. These high-resolution maps will be crucial in creating evidence for the relevant authorities to respond appropriately to local sources of pollution and to improve the understanding of transportation of urban PM.

Sex difference in the association between solid fuel use and cognitive function in rural China

BACKGROUND

Whether indoor air pollution from solid fuel use is associated with cognitive function remains unclear.

OBJECTIVE

This study aims to examine the association of solid fuel use with the risk of cognitive impairment in males and females.

METHODS

The data was from the China Health and Retirement Longitudinal Study (CHARLS). Self-reported heating and cooking fuel were categorized as clean fuel (solar, liquefied gas, natural gas, or electricity) and solid fuel (coal, biomass charcoal, wood, or straw). Cognitive function, including orientation and attention, episodic memory, and visuospatial abilities, was assessed using standardized questionnaires.

RESULTS

A total of 7824 individuals were included in our study (aged 57.0 ± 9.3, 46.2% female), with 47.0% and 76.0% used solid fuel for cooking and heating, respectively. There was an interaction between sex and solid fuel use for cooking (P=0.008) for the progress of cognitive impairment. Solid fuel use for cooking was associated with a larger decrease in cognitive function score in females (β=-0.832; 95% CI: -1.043, -0.622; P < 0.001) than in males (β=-0.487; 95% CI: -0.671, -0.302; P < 0.001). The sex difference remained with further adjustment of covariates (β=-0.321; 95% CI: -0.503, -0.138; P=0.001 for males; β=-0.534; 95% CI: -0.745, -0.324; P < 0.001 for females). For heating, the interaction between sex and solid fuel was not statistically significant (P=0.156). After controlling for the covariates, solid fuel use for heating was inversely associated with a 0.321 unit of decrease of cognitive function score (β=-0.321; 95% CI: -0.652, 0.009; P=0.057) in males, and a 0.598 unit of decrease of cognitive function (β=-0.598; 95% CI: -0.978, -0.218; P=0.002) in females.

CONCLUSION

In conclusion, solid fuel use for cooking and heating was significantly associated with a higher risk of cognitive impairment. Furthermore, for the first time, we found that the effect of solid fuel use on cognitive function in females was greater than in males.

Early life exposure to air pollution impacts neuronal and glial cell function leading to impaired neurodevelopment

The World Health Organisation recently listed air pollution as the most significant threat to human health. Air pollution comprises particulate matter (PM), metals, black carbon and gases such as ozone (O₃ ), nitrogen dioxide (NO₂ ) and carbon monoxide (CO). In addition to respiratory and cardiovascular disease, PM exposure is linked with increased risk of neurodegeneration as well as neurodevelopmental impairments. Critically, studies suggest that PM crosses the placenta, making direct in utero exposure a reality. Rodent models reveal that neuroinflammation, neurotransmitter imbalance and oxidative stress are triggered following gestational/early life exposure to PM, and may be exacerbated by concomitant mitochondrial dysfunction. Gestational PM exposure (potentiated by mitochondrial impairment in the metabolically active neonatal brain) not only impacts neurodevelopment but may sensitise the brain to subsequent cognitive impairment. Having reviewed this field, we conclude that strategies are urgently required to reduce exposure to PM during this sensitive developmental period.

Real-World Contribution of Electrification and Replacement Scenarios to the Fleet Emissions in West Midland Boroughs, UK

This study reports the likely real-world effects of fleet replacement with electric vehicles (EVs) and higher efficiency EURO 6 vehicles on the exhaustive emissions of NOx, PM, and CO2 in the seven boroughs of the West Midlands (WM) region, UK. National fleet composition data, local EURO distributions, and traffic compositions were used to project vehicle fleet compositions for different roads in each borough. A large dataset of real-world emission factors including over 90,000 remote-sensing measurements, obtained from remote sensing campaigns in five UK cities, was used to parameterize the emission profiles of the studied scenarios. Results show that adoption of the fleet electrification approach would have the highest emission reduction potential on urban roads in WM boroughs. It would result in maximum reductions ranging from 35.0 to 37.9%, 44.3 to 48.3%, and 46.9 to 50.3% for NOx, PM, and CO2, respectively. In comparison, the EURO 6 replacement fleet scenario would lead to reductions ranging from 10.0 to 10.4%, 4.0 to 4.2%, and 6.0 to 6.4% for NOx, PM, and CO2, respectively. The studied mitigation scenarios have higher efficacies on motorways compared to rural and urban roads because of the differences in traffic fleet composition. The findings presented will help policymakers choose climate and air quality mitigation strategies.

Association between solid fuel use and cognitive decline among middle-aged and elderly Chinese adults: a longitudinal study

This study was conducted to investigate (1) the association between solid fuel use for cooking and cognitive function; (2) the moderating effects of gender and residential area on cognitive scores among solid fuel users; and (3) the effects of solid fuel use on cognitive decline among different gender and age subgroups in 2011–2018. A total of 5140 Chinese middle-aged and elderly participants were successfully followed for 7 years (2011–2018). Solid fuel use was self-reported as using solid fuel for cooking at home, and cognitive function was assessed by 4 parts: episodic memory, time orientation, numerical ability and picture drawing. After adjusting for covariates, solid fuel users had lower cognitive scores, and the moderation effects of gender and residence on cognitive function were significant among the solid fuel users. In addition, compared with the group of clean fuel users, solid fuel users had a faster decline rate of cognitive function among the subgroups of female and elderly people.

Directional Water Transfer Janus Nanofibrous Porous Membranes for Particulate Matter Filtration and Volatile Organic Compound Adsorption

In order to reduce the possible harm caused by air pollution, excellent personal protective materials are attracting more and more attention. Therefore, the research of multifunctional materials that can filter particulate matter (PM) and volatile organic compounds (VOCs) simultaneously is of great significance. In addition, in cold weather, water vapor in the exhaled gas condenses into small droplets inside the respirator causing uncomfortable feeling of dampness. Herein, we prepared several types of cyclodextrin-containing Janus nanofibrous porous membranes by electrospinning, which can efficiently filter PM of different sizes in the air, effectively adsorb VOCs, and orientate moisture from exhaled gas to the outside of the membranes to provide a dry and comfortable environment. These advantageous features, combined with the cheap price and easy availability of component materials and low respiratory resistance, highlight the great potential of these Janus nanofibrous porous membranes in the development of personal wearable air purifiers.

Effects of PM2.5 on Third Grade Students' Proficiency in Math and English Language Arts

Fine particulate air pollution is harmful to children in myriad ways. While evidence is mounting that chronic exposures are associated with reduced academic proficiency, no research has examined the frequency of peak exposures. It is also unknown if pollution exposures influence academic proficiency to the same degree in all schools or if the level of children's social disadvantage in schools modifies the effects, such that some schools' academic proficiency levels are more sensitive to exposures. We address these gaps by examining the percentage of third grade students who tested below the grade level in math and English language arts (ELA) in Salt Lake County, Utah primary schools (n = 156), where fine particulate pollution is a serious health threat. More frequent peak exposures were associated with reduced math and ELA proficiency, as was greater school disadvantage. High frequency peak exposures were more strongly linked to lower math proficiency in more advantaged schools. Findings highlight the need for policies to reduce the number of days with peak air pollution.

Real-world assessment of vehicle air pollutant emissions subset by vehicle type, fuel and EURO class: New findings from the recent UK EDAR field campaigns, and implications for emissions restricted zones

This paper reports upon and analyses vehicle emissions measured by the Emissions Detecting and Reporting (EDAR) system, a Vehicle Emissions Remote Sensing System (VERSS) type device, used in five UK based field campaigns in 2016 and 2017. In total 94,940 measurements were made of 75,622 individual vehicles during the five campaigns. The measurements are subset into vehicle type (bus, car, HGV, minibus, motorcycle, other, plant, taxi, van, and unknown), fuel type for car (petrol and diesel), and EURO class, and particulate matter (PM), nitric oxide (NO) and nitrogen dioxide (NO₂) are reported. In terms of recent EURO class emission trends, NO and NO_x emissions decrease from EURO 5 to EURO 6 for nearly all vehicle categories. Interestingly, taxis show a marked increase in NO₂ emissions from EURO 5 to EURO 6. Perhaps most concerningly is a marked increase in PM emissions from EURO 5 to EURO 6 for HGVs. Another noteworthy observation was that vans, buses and HGVs of unknown EURO class were often the dirtiest vehicles in their classes, suggesting that where counts of such vehicles are high, they will likely make a significant contribution to local emissions. Using Vehicle Specific Power (VSP) weighting we provide an indication of the magnitude of the on-site VERSS bias and also a closer estimate of the regulatory test/on-road emissions differences. Finally, a new 'EURO Updating Potential' (EUP) factor is introduced, to assess the effect of a range of air pollutant emissions restricted zones either currently in use or marked for future introduction. In particular, the effects of the London based Low Emission Zone (LEZ) and Ultra-Low Emissions Zone (ULEZ), and the proposed Birmingham based Clean Air Zone (CAZ) are estimated. With the current vehicle fleet, the impacts of the ULEZ and CAZ will be far more significant than the LEZ, which was introduced in 2008.

Effects of Progressive Resistance Training on Cognition and IGF-1 Levels in Elder Women Who Live in Areas with High Air Pollution

The aim of this study was to determine the effects of a muscular strength programme on the levels of insulin-like growth factor-1 (IGF-1) and cognitive status in elder women with mild cognitive impairment who lived in areas of high air pollution. A total of 157 women participated in the study, distributed in four groups: Active/Clean (AC n = 38) and Active/Pollution (AP n = 37), who carried out a progressive resistance training programme for 24 months, and Sedentary/Clean (SC n = 40) and Sedentary/Pollution (SP n = 42). Maximum strength in the upper and lower limbs (1RM), cognition (Mini-Mental Scale Examination (MMSE)) and blood IGF-1 were evaluated. At the beginning of the intervention, there were no differences between the groups in the assessed variables. The active groups which carried out the resistance training programme (AC and AP), registered better results in IGF-1 than the sedentary groups. These differences were statistically significant in AC vs. SC (p < 0.01) and AP vs. SC (p < 0.05). Regarding MMSE, group AC registered the highest score increases (+8.2%) (significantly better than the other groups), while group SP worsened (−7%) significantly compared to the other three groups. In conclusion, resistance training had a positive effect on IGF-1, while sedentary behaviour and air pollution had a negative effect on cognitive status.

Vertical Profiles of Pollution Particle Concentrations in the Boundary Layer above Paris (France) from the Optical Aerosol Counter LOAC Onboard a Touristic Balloon

Atmospheric pollution by particulate matter represents a significant health risk and needs continuous monitoring by air quality networks that provide mass concentrations for PM10 and PM2.5 (particles with diameter smaller than 10 μm and 2.5 μm, respectively). We present here a new approach to monitor the urban particles content, using six years of aerosols number concentration measurements for particles in the 0.2−50 μm size range. These measurements are performed by the Light Optical Aerosols Counter (LOAC) instrument onboard the tethered touristic balloon “Ballon de Paris Generali”, in Paris, France. Such measurements have allowed us first to detect at ground a seasonal variability in the particulate matter content, due to the origin of the particles (anthropogenic pollution, pollens), and secondly, to retrieve the mean evolution of particles concentrations with height above ground up to 150 m. Measurements were also conducted up to 300 m above ground during major pollution events. The vertical evolution of concentrations varies from one event to another, depending on the origin of the pollution and on the meteorological conditions. These measurements have shown the interest of performing particle number concentrations measurements for the air pollution monitoring in complement with regulatory mass concentrations measurement, to better evaluate the intensity of the pollution event and to better consider the effect of smallest particles, which are more dangerous for human health.