Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
Department of Environmental Science, Aarhus University, Roskilde, Denmark
Air pollution and Autism in Denmark
Previous autism spectrum disorder (ASD) and air pollution studies focused on pregnancy exposures, but another vulnerable period is immediate postnatally. Here, we examined early life exposures to air pollution from the pre- to the postnatal period and ASD/ASD subtypes in the Danish population.
With Danish registers, we conducted a nationwide case-control study of 15,387 children with ASD born 1989-2013 and 68,139 population controls matched by birth year and sex identified from the birth registry. We generated air dispersion model (AirGIS) estimates for NO2, SO2, PM2.5 and PM10 at mothers' home from 9 months before to 9 months after pregnancy and calculated odds ratios (OR) and 95% confidence intervals (CI), adjusting for parental age, neighborhood socio-economic indicators, and maternal smoking using conditional logistic regression.
In models that included all exposure periods, we estimated adjusted ORs for ASD per interquartile range (IQR) increase for 9 month after pregnancy with NO2 of 1.08 (95% CI: 1.01, 1.15) and with PM2.5 of 1.06 (95% CI: 1.01, 1.11); associations were smaller for PM10 (1.04; 95% CI: 1.00, 1.09) and strongest for SO2 (1.21; 95% CI: 1.13, 1.29). Also, associations for pollutants were stronger in more recent years (2000-2013) and in larger cities compared with provincial towns/rural counties. For particles and NO2, associations were only specific to autism and Asperger diagnoses.
Our data suggest that air pollutant exposure in early infancy but not during pregnancy increases the risk of being diagnosed with autism and Asperger among children born in Denmark.
Institute of Health and Environment, Seoul National University, Seoul
Particulate Matter Mortality Rates and Their Modification by Spatial Synoptic Classification
Air pollution levels are highly correlated with temperature or humidity, so we investigated the relationship between PM10 and the spatial synoptic classification (SSC) scheme on daily mortality, according to age group and season. Daily death data for 2000-2014 from Seoul, Korea, were acquired, and time-series analysis was applied with respect to season and to each of seven distinct SSC types: dry moderate (DM); dry polar (DP); dry tropical (DT); moist moderate (MM); moist polar (MP); moist tropical (MT); and transition (T). Modification effects were estimated for daily, non-accidental, cardiovascular, and respiratory mortality between PM10 and SSC types. The following SSC-type-specific increased mortalities were observed, by cause of death: non-accidental mortality: DT (1.86%) and MT (1.86%); cardiovascular mortality: DT (2.83%) and MM (3.00%); respiratory mortality: MT (3.78%). Based on simplified weather types, increased PM10 effects in non-accidental mortality rates were observed in dry (1.54%) and moist (2.32%) conditions among those aged 40-59 years and were detected regardless of conditions in other age groups: 60-74 (1.11%), 75-84 (1.55%), and 85+ (1.75%). The effects of particulate air pollution, by SSC, suggest the applicability of SSC to the comparison and understanding of acute effects of daily mortality based on weather type.
Xiang Ya Nursing School, Central South University, Changsha, Hunan, China
Ambient air pollution exposure and risk of depression: A systematic review and meta-analysis of observational studies.
Recent studies have reported an association between air pollution exposure and depression, with inconsistent results. To address this controversy, we conducted a systematic review and meta-analysis of published observational studies that investigated outdoor air pollution and depression. Five electronic databases were searched, and fifteen articles were finally identified. Pooled odds risks were calculated separately based on pollutant type, exposure duration and outcome. Subgroup analyses were conducted based on design, population, important potential confounders, and pollutants levels. We found a significantly increased risk of depression with long-term exposure to PM2.5 and short-term exposure to PM10, NO2, SO2, CO. No evidence was found in the association between exposure to O3 and depression. Besides, exposure to high levels of pollutants indicates a higher risk of depression. Our results highlight the necessity of air pollution control for depression. However, further studies with standardized methods are still required to support the results due to the inconsistent results in stratified analyses and methodological limitations of the included studies.
Department of Physiology, Physiology Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Gallic acid protects particulate matter (PM10) triggers cardiac oxidative stress and inflammation causing heart adverse events in rats.
Previous studies have shown that exposure to particulate matter (PM) increased variety of health problems, particularly cardiovascular diseases leading to premature mortality. The cardiac effects of particulate matter containing PM10 include increased infarct size, decreased heart function, and increased arrhythmias in experimental ischemia-reperfusion models in rats. The aim of this study was to evaluate the effects of particles with an aerodynamic diameter smaller than 10 μm (PM10) on isolated-rat heart and also to determine the efficacy of gallic acid (GA) as a preventive agent in oxidative damage. The healthy rats were divided into 8 equal groups which served as, control, GA, PM10 (0.5, 2.5, and 5 mg/kg), and PM10+GA groups. PM10 administered into the lungs via the trachea in two stages with 48-h interval. After all experiments, the electrocardiogram was recorded. Then, the hemodynamic parameters and ventricular arrhythmias in rat isolated-hearts were assessed using Langendorff apparatus and according to the Lambeth conventions. In addition, the inflammation and oxidative stress factors in cardiac tissues were evaluated in all groups. The obtained results showed that the exposure to PM caused to decrease in cardiac hemodynamic and electrocardiogram parameters. Also, in PM10 rat groups, the IL-6, TNF-α, and oxidative stress parameters were increased. Gallic acid preserved the value of cardiac parameters and inflammation in rat hearts. In summary, we added a novel therapeutic effect of gallic acid for cardiac dysfunction induced by particulate matter. These findings could be related to antioxidant and antiinflammation properties and the obtained results suggest that natural antioxidant like gallic acid could be a therapeutic agent in prevention and management of health issues in the polluted areas of the world.
Faculty of Medicine, Department of Physiology , Persian Gulf Physiology Research Center, Ahvaz Jundishapur University of Medical Sciences , Ahvaz , Iran
In vivo and in vitro evidence for the involvement of Nrf2-antioxidant response element signaling pathway in the inflammation and oxidative stress induced by particulate matter (PM10): the effective role of gallic acid.
Environmental pollution is one of the risk factors for respiratory diseases. The nuclear factor erythroid 2-related factor 2 (Nrf2) is the major mechanisms contributing to cellular defense against oxidative damage. Gallic acid (GA) is regarded as potent anti-inflammatory and antioxidant agents. The aim was to evaluate the role of Nrf2 pathway in particulate matter (PM10) exposure on lung and epithelial cells with an emphasis on the role of GA. In in vivo part, the rats were divided as control, GA (30 mg/kg), particulate matter (PM) (0.5, 2.5, and 5 mg/kg), and PM + GA. In in vitro study, the cells were divided as control, PM10 (100, 250, and 500 µg/ml), GA (50 µmol/L) and PM10+GA. Inflammation, oxidative stress and Nrf2-pathway factors were assessed. PM10 groups showed a considerable increase in the epithelial permeability and inflammatory parameters. We also found a significant decrease in the expression of Nrf2 and its up-stream regulators genes. Accordingly, the biosynthesis of glutathione (GSH) and other antioxidant activities significantly decreased. Gallic acid was identified to restore the antioxidant status to the normal levels. Our findings approved that Nrf2 is involved in PM10-induced oxidative damages and showed that Nrf2 activation by natural agents could ameliorate respiratory injuries induced by PM10.
Department of Toxicogenomics, GROW School for Oncology and Developmental Biology, Maastricht University, Maastricht, the Netherlands
Short-term exposure to traffic-related air pollution reveals a compound-specific circulating miRNA profile indicating multiple disease risks
Traffic-related air pollution (TRAP) is a complex mixture of compounds that contributes to the pathogenesis of many diseases including several types of cancer, pulmonary, cardiovascular and neurodegenerative diseases, and more recently also diabetes mellitus. In search of an early diagnostic biomarker for improved environmental health risk assessment, recent human studies have shown that certain extracellular miRNAs are altered upon exposure to TRAP. Here, we present a global circulating miRNA analysis in a human population exposed to different levels of TRAP. The cross-over study, with sampling taking place during resting and physical activity in two different exposure scenarios, included for each subject personal exposure measurements of PM10,PM2.5, NO, NO2, CO, CO2, BC and UFP. Next-generation sequencing technology was used to identify global circulating miRNA levels across all subjects. We identified 8 miRNAs to be associated with the mixture of TRAP and 27 miRNAs that were associated with the individual pollutants NO, NO2, CO, CO2, BC and UFP. We did not find significant associations between miRNA levels and PM10 or PM2.5. Integrated network analysis revealed that these circulating miRNAs are potentially involved in processes that are implicated in the development of air pollution-induced diseases. Altogether, this study demonstrates that signatures consisting of circulating miRNAs present a potential novel biomarker to be used in health risk assessment.
National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands; Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, the Netherlands
Associations of combined exposures to surrounding green, air pollution and traffic noise on mental health.
Evidence is emerging that poor mental health is associated with the environmental exposures of surrounding green, air pollution and traffic noise. Most studies have evaluated only associations of single exposures with poor mental health.
To evaluate associations of combined exposure to surrounding green, air pollution and traffic noise with poor mental health.
In this cross-sectional study, we linked data from a Dutch national health survey among 387,195 adults including questions about psychological distress, based on the Kessler 10 scale, to an external database on registered prescriptions of anxiolytics, hypnotics & sedatives and antidepressants. We added data on residential surrounding green in a 300 m and a 1000 m buffer based on the Normalized Difference Vegetation Index (NDVI) and a land-use database (TOP10NL), modeled annual average air pollutant concentrations (including particulate matter (PM10, PM2.5), and nitrogen dioxide (NO2)) and modeled road- and rail-traffic noise (Lden and Lnight) to the survey. We used logistic regression to analyze associations of surrounding green, air pollution and traffic noise exposure with poor mental health.
In single exposure models, surrounding green was inversely associated with poor mental health. Air pollution was positively associated with poor mental health. Road-traffic noise was only positively associated with prescription of anxiolytics, while rail-traffic noise was only positively associated with psychological distress. For prescription of anxiolytics, we found an odds ratio [OR] of 0.88 (95% CI: 0.85, 0.92) per interquartile range [IQR] increase in NDVI within 300 m, an OR of 1.14 (95% CI: 1.10, 1.19) per IQR increase in NO2 and an OR of 1.07 (95% CI: 1.03, 1.11) per IQR increase in road-traffic noise. In multi exposure analyses, associations with surrounding green and air pollution generally remained but attenuated. Joint odds ratios [JOR], based on the Cumulative Risk Index (CRI) method, of combined exposure to air pollution, traffic noise and decreased surrounding green were higher than the ORs of single exposure models. Associations of environmental exposures with poor mental health differed somewhat by age.
Studies including only one of these three correlated exposures may overestimate the influence of poor mental health attributed to the studied exposure, while underestimating the influence of combined environmental exposures.