E-POSTER GALLERY (ID 409)

P-0001 - Comprehensive approach for reducing health risks due to indoor air pollutants

Abstract Control Number
1287
Abstract Body
Individuals living in an indoor environment are typically exposed to a greater variety of air pollutants than in an outdoor environment. Numerous sources of chemical emissions are found in the indoor environment, depending on the building materials as well as the lifestyle of the occupants. The quality of the indoor environment considerably impacts public health. Japan has established Indoor Air Quality guidelines (IAQGs) for 13 chemicals, including formaldehyde, acetaldehyde, xylene, ethylbenzene, styrene, 1,4-dichlorobenzene, and toluene. However, the pollutant types and concentrations have been inconsistent over time because of altered lifestyles and the development of novel household products and building materials. Therefore, a comprehensive approach and action plan for the overall reduction of health risks because of indoor air pollutants are required for public health protection. To determine the high-risk indoor air pollutants that should be reduced, a preliminary risk assessment using data from nationwide exposure assessments and existing hazard data was conducted. As the result, 11 indoor air pollutants: 2-ethyl-1-hexanol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, ethyl acetate, butyl acetate, propylene glycol monomethyl ether, 3-methoxy-3-methylbutanol, diethylene glycol methyl ether, diethylene glycol ethyl ether, propylene glycol monomethyl ether acetate, and methyl isobutyl ketone were identified. Subsequently, we reviewed the hazard or toxicological data for the 13 chemicals with established IAQGs and the 11 novel chemicals without established IAQGs to update their hazard assessments. The reference values for acute and chronic effects were determined from the reviewed information. The process and result of the preliminary risk assessment and the progress of the updated hazard assessments are reported.
E-POSTER GALLERY (ID 409)

P-0002 - Systematic Review on Untargeted Metabolomics Application in Air Pollution Health Research: Current Progress, Analytical Challenges, and Future Direction

Abstract Control Number
1394
Abstract Body
Background: Understanding the mechanistic basis of air pollution toxicity is dependent on accurately characterizing both exposure and health along a complete dose-to-response pathway. Untargeted metabolomics, an analysis of small-molecule metabolic phenotypes, may offer improved estimation to complex environmental mixtures. The field remains nascent, however, with questions concerning the coherence and generalizability of findings across study cohorts and analytical platforms. Methods: We conducted a systematic review to 1) summarize recent research of air pollution studies utilizing untargeted metabolomics and; 2) identify gaps in the peer-reviewed literature and opportunities for addressing these gaps in future designs. Using PRISMA guidelines, we screened articles published within MEDLINE and Web of Science between 1/1/05 and 12/21/19. Two reviewers independently screened a total of 1,074 abstracts, with discrepancies resolved by a third reviewer. Results: 22 studies fulfilled eligibility criteria and were included in this review. Over 300 metabolic features were associated with at least one or more air pollutant, with 52 features validated using authentic reference standards. Hypoxanthine, arginine, and histidine were among 12 metabolites consistently exhibiting associations with fine particulate matter and nitrogen dioxide exposure in at least three independent studies. Oxidative stress and inflammation related pathways, including glutathione, leukotriene and vitamin E metabolism, were the most commonly perturbed pathways reported in over 55% of studies. Challenges and gaps exist in metabolite annotation; over 80% of the reported features were not chemically annotated, limiting interpretability and generalizability of the findings. Conclusions: Numerous investigations have demonstrated the feasibility of using untargeted metabolomics as a platform linking exposure to internal dose and biological response. Metabolic perturbations in oxidative stress and acute inflammation pathway were associated with both short- and long- term air pollution exposure. Future directions should focus on validation of these findings via hypothesis-driven protocols and technical advances in metabolic annotation and quantification.
E-POSTER GALLERY (ID 409)

P-0003 - Exposure to particulate matter and risk of amyotrophic lateral sclerosis: A case-control study in Northern Italy

Abstract Control Number
1495
Abstract Body
Background: Amyotrophic lateral sclerosis (ALS) is progressive neurodegenerative disease with still unknown etiology. Role of occupational and environmental risk factors has been investigated, including outdoor air pollutants, which have been recently associated to an excess disease risk. We carried out a case-control study in order to assess if environmental exposure to particulate matter ≤10 µm (PM10) may increase ALS risk. Methods: We recruited patients referred to the Modena Neurology Unit between 1994-2015 and controls from the Modena province population. Using a validated geographical information system-based dispersion model, we geocoded subjects’ addresses of residence at the time of diagnosis and we estimated outdoor air PM10 concentrations for each subjects. We computed odds ratio (OR) and 95% confidence interval (CI) of ALS according to increasing PM10 exposure, using an unconditional logistic regression model age- and sex-adjusted. Results: For the 132 study participants (52 cases/80 controls), mean of annual average and maximum PM10 concentrations were 5.2 and 38.6µg/m3, respectively. Using fixed cutpoints at 5, 10 and 20 of average annual PM10 concentrations, compared with subjects <5µg/m3, we did not find evidence for an excess ALS risk associated with PM10 exposure, since OR was 0.87 (95% CI 0.39-1.96), 0.94 (0.24-3.70), and 0.87 (0.05-15.01) at 5-10, 10-20 and ≥20µg/m3, respectively. Using maximum annual PM10 concentrations, we found an excess ALS risk for subjects exposed at 10-20µg/m3 (OR=4.27, 0.69-26.51) compared with exposure below 10µg/m3, although the risk tended to decrease at higher PM10 concentrations, with OR of 1.49 (0.39-5.75) at 20-50, and 1.16 (0.98-4.82) at ≥50µg/m3. Conclusions: Our findings do not suggest that PM10 exposure is associated with ALS risk. However, some evidence of an increased risk associated with maximum annual exposure concentrations, although statistically imprecise, suggests the need of further investigations, also considering the high concentrations of particulate matter characterizing Northern Italy.
E-POSTER GALLERY (ID 409)

P-0004 - Short-term PM10 exposure is associated with lower severity of manic episodes in hospitalized bipolar patients

Abstract Control Number
1632
Abstract Body
Background: Bipolar Disorder (BD) alternates depressive, manic or hypomanic phases. A manic episode (ME) is the main psychopathological condition of BD and it often requires hospitalization. Air pollution is thought to play a role in onset and exacerbation of several psychiatric disorders. We thus aimed to verify the association between exposure to particulate matter ≤10µm (PM10) and ME severity, assessed through the Young Mania Rating Scale (YMRS). Methods: We evaluated clinical records regarding 414 hospital admissions of 186 patients residing in Milan (Italy), hospitalized for ME in the Psychiatry Unit of the Policlinico Hospital from 2007 to 2019. Patients were assigned mean daily PM10 and apparent temperature levels of the city of Milan. Different exposure windows were considered: single days preceding hospitalization (lag 0 to 15) and their average estimates (lag 0-1 to 0-15). We applied mixed effect models, adjusted for age at hospitalization/onset, sex, smoking habit, number of cigarettes per day, year of hospitalization, season, and apparent temperature. Results: Short-term PM10 exposure was associated with a reduction in YMRS, both when considering daily lags [β: -0.46 (95% Confidence Interval: -0.87; -0.06) at lag0] and their average [-0.50 (-0.94; -0.07) at lag0-1]. YMRS was higher in psychotic patients (24.7 vs. 16.6, p < 0.001) and lower when considering ME with vs. without mixed components (18.2 vs. 21.2, p < 0.001). Interestingly, while PM10 did not influence the risk of patients being psychotic at admission, it was associated with a 34% increased risk of having a ME with mixed features (i.e. with dysphoric and/or depressive symptoms) at lag0-1 [Odds Ratio: 1.34 (1.01; 1.78)]. Conclusions: Our findings show that PM10 exposure moves the ME towards the depressive pole of the BD spectrum and increases the probability of hospitalization for ME with mixed components.
E-POSTER GALLERY (ID 409)

P-0005 - Attributable risk and economic cost of hospital admissions for mental disorders due to PM2.5 in Beijing

Abstract Control Number
1702
Abstract Body
Background Few studies have estimated the attributable risk and economic cost of mental disorders (MDs) due to particulate matters with aerodynamic diameter of less than 2.5 µm (PM2.5) exposure in Beijing.
Objectives This study aims to identify the possible correlation between PM2.5 and risk of hospital admissions (HAs) for MDs in Beijing and calculate the attributable risk and economic cost.
Methods A generalized additive model (GAM) with controlling for time trend, meteorological conditions, holidays and day of the week was used to estimate the associations. Stratified analyses were performed by age, gender and season. We further estimated the health and economic burden of HAs for MDs attributable to PM2.5.
Results A total of 17,252 HAs for MDs were collected. A 10 µg/m3 daily increase in PM2.5 was associated with a statistically significant risk increase of 3.55% for HAs for MDs. The effects of PM2.5 exposures on HAs for MDs were more pronounced in males, elderly (≥65 years old) individuals and in cold seasons. Using WHO's air quality guidelines as the reference, 15.12% of HAs (2,609 person-times out of 17,252 person-times) and 16.19% of the related medical expenses (51.86 million CNY out of 320.3 million CNY) for MDs were attributed to PM2.5 during the study period.
Conclusion PM2.5 accounts for substantial morbidity and economic burden of MDs for both the society and households, which shows environmental protections are essential to improve mental health status of the population.
E-POSTER GALLERY (ID 409)

P-0006 - Ensemble averaging based high resolution PM2.5 exposure assessment in two major Indian cities over 2010 to 2016

Abstract Control Number
1765
Abstract Body
Aim: In this work, we retrospectively assessed daily average PM2.5 exposure at 1 km × 1 km grids in two major Indian cities, Delhi and Chennai from 2010-2016, using multiple data sources and ensemble averaging approaches that combine machine learning algorithms.
Methods: We implemented a multi-stage modeling exercise involving satellite data, land use variables, reanalysis based meteorological variables and population density. The relationship between PM2.5 and spatiotemporal predictors was modeled using six learners; generalized additive model, elastic net, support vector regressions, neural networks, random forests and extreme gradient boosting. Predictions from each base learner was combined under a generalized additive model framework with penalized splines and tensor product smoothing. Prediction accuracy was assessed using cross-validated(CV) R2, root mean squared error and bias.
Results: Predicted average annual PM2.5 concentrations in Delhi ranged from 87 to 138 μg/m3 over 2010 to 2016. Average CV-R² ranged from 0.69-0.92 for the ensemble averaged (EA) model across the years with annual average concentrations ranging from 104 to 139 μg/m³. The predictions were characterized by higher bias and root mean squared error in the fall and winter compared to summer and monsoon seasons. Spatial CV-R² (yearly average) varied between 0.91-0.99, while temporal CV-R² (daily variability) ranged from 0.65-0.90, showing adequate model performances. We demonstrated important seasonal and geographical differences in PM2.5 particulate matter concentrations using the model outputs. Modeling for Chennai is ongoing and preliminary predictions will be shown.
Conclusion: We have developed a detailed exposure assessment for ambient air pollution in two distinct cities in India, with large differences in PM2.5 levels, that are critical for estimating effects on health. We also demonstrate the advantages of ensemble averaging and machine learning based hybrid modeling, which can be used to scale up this exercise to the national level.
E-POSTER GALLERY (ID 409)

P-0007 - do ultrafine particles confound studies on noise and cardiovascular disease?

Abstract Control Number
1795
Abstract Body
Background:Ultrafine particles (UFP) are emitted by both jet engine aircraft and road traffic and may potentially confound associations between noise and health outcomes. However, neither UFP or noise are routinely measured resulting in a lack of understanding of their relationship. Methods: We conducted repeated short-term measurements with portable sensors (noise - Cirrus Research Optimus sound level meter (CR:171B); PNC - TSI 3007 condensation particle counter) to assess the correlation between noise and UFP number concentrations (PNC) for aircraft and road traffic. Noise and PNC were measured contemporaneously for 30-minutes at 160 sites (repeated three times at a range of site types) in Norwich, a medium size city in the east of England, and repeatedly up to 71 times per site at nine sites (501 in total) around Gatwick airport. Results:In Combining all measurements at Gatwick Airport the correlation between noise and PNC was very weak (ρ = 0.11). Strongest correlations were moderate (|>0.4-0.6|) at a residential site 1.3 km north of the runway and a site 0.6 km south of the runway. The correlation between noise and PNC in Norwich was overall moderate (ρ = 0.52) and weak (ρ <0.4) for roadside sites (n = 55) and urban background sites (n = 90) respectively. Conclusion: Results suggest that PNC are unlikely to be a major confounder in epidemiological studies of aircraft or road noise and cardiovascular disease.
E-POSTER GALLERY (ID 409)

P-0008 - A comparison of approaches to estimate traffic-related PM2.5 in a study of commuters

Abstract Control Number
1855
Abstract Body
Background/Aim: Associations between exposure to traffic-related fine particulate matter (tr-PM2.5) and health are not fully understood. Exposure to tr-PM2.5 while commuting may reflect an important exposure environment relevant for health. However, estimating exposure to tr-PM2.5 is challenging because tr-PM2.5 is a spatially heterogeneous chemical mixture that cannot generally be directly observed. We compare two approaches to estimate personal exposure to tr-PM2.5 among commuters.
Methods: We measured personal exposure to continuous PM2.5 and 48-hour integrated PM2.5 metals and black carbon (BC) for 49 women commuters in the DC metro area. We recorded vehicle trips across 48 hours using vehicle data loggers and dashboard cameras. We estimated tr-PM2.5 using two approaches: source apportionment and vehicle monitoring. The source apportionment approach applied Positive Matrix Factorization (PMF) to integrated PM2.5 constituents as in previous studies. The vehicle monitoring approach estimated average PM2.5 exposure during vehicle trips identified using vehicle monitors. We compared estimates of tr-PM2.5 using Spearman correlations and comparing tertile groups. We also compared vehicle monitoring tr-PM2.5 with two tracers of tr-PM2.5: 48-hour integrated BC and zinc.
Results: We fitted PMF to the integrated data and identified three sources: tailpipe emissions, salt, and road dust. Vehicle monitoring estimated personal tr-PM2.5 exposure with a mean of 6.7
ug/m3 (interquartile range: 2.5,7.7). The correlation between tailpipe emissions and vehicle monitoring was 0.22, with correlations for the other sources close to zero. The two approaches generally grouped commuters differently, with 62% of commuters in different tertiles for tailpipe emissions and vehicle monitoring. Results were similar when BC and zinc were used instead of estimated sources.
Conclusions: There were substantial differences between the two approaches for estimating tr-PM2.5 among commuters, indicating that using only integrated PM2.5 constituents may not be representative of commute-specific exposures. Future work will combine these two approaches to better estimate exposure to tr-PM2.5.
E-POSTER GALLERY (ID 409)

P-0009 - Ambient ozone exposure and amino acids metabolome in adolescents with overweight and obesity

Abstract Control Number
1916
Abstract Body
Ambient ozone exposure and amino acids metabolome in adolescents with overweight and obesity Background Air pollution is a public health problem already associated with increased cardiometabolic diseases, however metabolomic pathways involved in air pollution remain not clear, especially in vulnerable population like adolescents who are at a critical period for development. Therefore, the aim of this study was to evaluate the relation between short term ozone exposure and amino acid and acyl carnitines in blood metabolome.MethodsWe conducted a longitudinal study on 9 to 21 years old adolescent with overweight and obesity from Mexico City. Ambient ozone exposure and other meteorological variables were estimated based on participants' residential addresses, lag and cumulative average effects were assessed. Three serum measurements were evaluated in 197 participants at different times over six years of follow-up, 40 metabolites related to beta oxidation of fatty acids and gluconeogenesis were measured. Factor analysis of the 40 metabolites was performed to identify 3 indexes: acylcarnitine index, amino acid index and a mixed index. Finally, we used mixed effects models to evaluate the associations between ozone exposure, metabolomic indexes and the individual metabolite concentrations of the first five metabolites in the index.ResultsLag-1 day maximum ozone concentration was associated with lower concentrations of amino acid index. Alanine, leucine, valine and tyrosine had the higher scores in the amino acid index and each of this amino acid concentration were significant lower with lag-1 and 2 to 5-day average ozone concentration.ConclusionsThis study suggests that higher concentrations of ozone are associated with lower amino acid index scores and individual amino acid concentrations in adolescents with overweight and obesity.
E-POSTER GALLERY (ID 409)

P-0010 - Short-term Exposure to Ambient Particulate Elements and Epigenome-wide DNA Methylation in Older Men: the Normative Aging Study

Abstract Control Number
1931
Abstract Body
Background: Current research suggests that short- and intermediate- term exposure to ambient particulate matter is associated with global and gene-specific DNA methylation (DNAm), but little is known regarding the changes in epigenome-wide caused by particulate elements (PEs). Additionally, the potential pathways remain unknown.Objective: We evaluated short- to intermediate-term associations between ambient PEs and DNAm in epigenome-wide and identified potential biological pathways.Method: We collected whole blood samples from 691 elderly men in the Normative Aging Study (1999-2013) and measured epigenome-wide DNAm with the Illumina Infinium HumanMethylation450 BeadChip. Ambient PEs were measured daily at a fixed monitoring station and 5 different moving averages from short- to intermediate-term (current day to 28-day) were considered. Linear quantile mixed models were used to estimate the associations between 15 elements and DNAm (N=1, 262 visits), adjusting for fine particle mass, cell type, batch effects, age, body mass index, smoking, etc. Pathway analysis was also performed to explore the potential biologic mechanisms.Results: Short- to intermediate-term exposure to PEs was significantly associated with epigenome-wide DNAm, especially for 28-d moving average. We observed different Bonferroni significant CpGs for different PE, most of them related with aluminum, iron, silicon, lead, and, calcium. The pathway analyses suggest that the detrimental effects might be relevant to cell cycle, biosynthetic process, and signal transduction. We also found that there were several common genes significantly associated with calcium, silicon and lead, such as, neurodegenerative disease related gene tubulin folding cofactor D.Conclusions: Ours is the first study that find short- to intermediate-term effects on DNAm in epigenome-wide by ambient PEs, especially elements associated with road dust, oil combustion, and wood burning. Our findings provide insight into potential mechanistic pathways.
E-POSTER GALLERY (ID 409)

P-0011 - Transcriptome-wide analyses of the effects of ambient PM2.5 and carbonaceous constituents: results of the AIRLESS project

Abstract Control Number
1953
Abstract Body
Background: Transcriptome-wide analyses is emerging as a useful tool to investigate the unclear mechanism behind the well-documented health effects of air pollution. However, the evidence remains limited in human based studies and mainly focused on the ambient fine particles (PM2.5). Methods: This study investigated the changes in gene expression profiles in response to acute exposure to ambient PM2.5 and its carbonaceous constituents. Based on the AIRLESS panel study, 251 nonsmoking senior participants living in urban (N=123) and rural (N=128) Beijing, China have undergone 4 times blood drawn. Total RNA was sequenced with RNA-seq technology by Hi-seq X10. Daily average concentrations of PM2.5, elemental carbon (EC), and organic carbon (OC) in ambient air were measured at a nearby monitoring site. Linear mixed-effects model was used to screen differentially expressed genes in association with exposure to air pollutants with adjustment for demographic, socio-economic and lifestyle variables, and consideration of false discovery rate (FDR) < 0.05. Pathway enrichment analyses were performed with Metacore platform. Results: The numbers of significantly changed genes associated with the exposure to PM2.5, EC, and OC were 1841, 1719, and 1670, respectively. Large proportions of changed genes were overlapped among the three pollutants, and the number of genes that only associated with PM2.5 was 9. Top 50 significantly up-regulated genes were mostly involved in cell differentiation and inflammatory response (e.g. EVIB2, C5AR1, CD52, CSF2RB and CSF3R), while down-regulated genes mainly related to mitochondrial function and protein synthesis (e.g. UQCRH, UQCRB, ATP5E, COX6C and FAU). Pathway enrichment analyses suggested potential mechanisms including inflammatory response, oxidative stress, apoptosis and survival, and neurogenesis, e.g. IL-3 signaling via ERK and PI3K, were strongly associated with PM2.5, OC, and EC. Conclusions: EC and OC might play key roles in PM-induced health effects. Transcriptome-wide analyses helped to unveil the potential molecular mechanisms of such effects.
E-POSTER GALLERY (ID 409)

P-0012 - construction and verification of air quality health index in china

Abstract Control Number
2001
Abstract Body
Background: Air Quality Health Index (AQHI) was established in several countries and areas, and has showed validity in communicating health risks of air pollution. But there is a lack of unified AQHI in China. Methods: We contructed six indexes: AQHI_99, AQHI_98, AQHI_95, AQHI_log99, AQHI_log_98, and AQHI_log_95, by summing the excess total non-accidental mortality risks associated with PM2.5,O3, NO2, and SO2 and adjusting them to an arbitratry scale (1-10+). To adjust the distribution of the index, we logarithmic convert the sum of health risks. To avoied the maximun interference, we use the 99%, 98%, and 95% percentile of excess total non-accidental mortality risks of all counties in China as normalization factor. To verification the validity of communicating morbality and morbidity risk, we calculated the relationship between the AQHIs and morbality, anount of hospitalization, and outpatient number. According to the results, we chose the best AQHI. To test the ability of the AQHI to indicated a typical contamination event, we plotted the AQHI and air pollution concentration in several typical contamination event. And we also checked the consistency of AQHI and AQI. Results: AQHI_98 and AQHI_99 performed better in validity of communicating morbality and morbidity risk than AQI and other AQHIs. Given the current state of air pollution in China, we tended to opt for stricter standards: AQHI_98. An IQR increase of AQHI_98 was associated with a 1.0% (95% CI: 0.6 to 1.5) increase of non-accidental mortality in China and 2.0% (95% CI:1.8 to 2.1) increase of all causes hospital admissions in Beijing. This AQHI permforms good in indicating typical contamination events and does not conflict with AQI. Conclusions: We recommend AQHI_98 as Chinese AQHI. The AQHI is a more effective tool to communicate the health risk of air pollution in China.