Validation of the ICEBERG emergency room screening tool for early identification of older patients with geriatric consultation needs.

Background: The growing number of older and oldest-old patients often present in the emergency room (ER) with undiagnosed geriatric syndromes posing them at high risk for complications in acute care. Objective: To develop and validate an ER screening tool (ICEBERG) to capture 9 geriatric domains of risk in older patients. Design setting and participants: For construct validity we performed a chart-based study in 129 ER patients age 70 years and older admitted to acute geriatric care (pilot 1). For criterion validity we performed a prospective study in 288 ER patients age 70 years and older admitted to acute care (pilot 2). Exposure: In both validation steps, the exposure was ICEBERG test performance below and above the median score (10, range 0-30). Outcome measures and analysis: In pilot 1, we compared the exposure with results of nine tests of the Comprehensive Geriatric Assessment (CGA). In pilot 2, we compared the exposure assessed in the ER to following length of hospital stay (LOS), one-on-one nursing care needs, in-hospital mortality, 30-day re-admission rate, and discharge to a nursing home. Main results: Mean age was 82.9 years (SD 6.7; n = 129) in pilot 1, and 81.5 years (SD 7.0; n = 288) in pilot 2. In pilot 1, scoring ≥10 was associated with significantly worse performance in 8 of 9 of the individual CGA tests. In pilot 2, scoring ≥10 resulted in longer average LOS (median 7 days, IQR 4, 11 vs. 6 days, IQR 3, 8) and higher nursing care needs (median 1,838 min, IQR 901, 4,267 vs. median 1,393 min, IQR 743, 2,390). Scoring ≥10 also increased the odds of one-on-one nursing care 2.9-fold (OR 2.86, 95%CI 1.17-6.98), and the odds of discharge to a nursing home 3.7-fold (OR 3.70, 95%CI 1.74-7.85). Further, scoring ≥10 was associated with higher in-hospital mortality and re-hospitalization rates, however not reaching statistical significance. Average time to complete the ICEBERG tool was 4.3 min (SD 1.3). Conclusion: Our validation studies support construct validity of the ICEBERG tool with the CGA, and criterion validity with several clinical indicators in acute care.

Higher viral load and infectivity increase risk of aerosol transmission for Delta and Omicron variants of SARS-CoV-2.

BACKGROUND: Airborne transmission of SARS-CoV-2 is an important route of infection. For the wildtype (WT) only a small proportion of those infected emitted large quantities of the virus. The currently prevalent variants of concern, Delta (B1.617.2) and Omicron (B.1.1.529), are characterized by higher viral loads and a lower minimal infective dose compared to the WT. We aimed to describe the resulting distribution of airborne viral emissions and to reassess the risk estimates for public settings given the higher viral load and infectivity. METHOD: We reran the Monte Carlo modelling to estimate viral emissions in the fine aerosol size range using available viral load data. We also updated our tool to simulate indoor airborne transmission of SARS-CoV-2 by including a CO2 calculator and recirculating air cleaning devices. We also assessed the consequences of the lower critical dose on the infection risk in public settings with different protection strategies. RESULTS: Our modelling suggests that a much larger proportion of individuals infected with the new variants are high, very high or super-emitters of airborne viruses: for the WT, one in 1,000 infected was a super-emitter; for Delta one in 30; and for Omicron one in 20 or one in 10, depending on the viral load estimate used. Testing of the effectiveness of protective strategies in view of the lower critical dose suggests that surgical masks are no longer sufficient in most public settings, while correctly fitted FFP2 respirators still provide sufficient protection, except in high aerosol producing situations such as singing or shouting. DISCUSSION: From an aerosol transmission perspective, the shift towards a larger proportion of very high emitting individuals, together with the strongly reduced critical dose, seem to be two important drivers of the aerosol risk, and are likely contributing to the observed rapid spread of the Delta and Omicron variants of concern. Reducing contacts, always wearing well-fitted FFP2 respirators when indoors, using ventilation and other methods to reduce airborne virus concentrations, and avoiding situations with loud voices seem critical to limiting these latest waves of the COVID-19 pandemic.

Bisdemethoxycurcumin Promotes Apoptosis and Inhibits the Epithelial-Mesenchymal Transition through the Inhibition of the G-Protein-Coupled Receptor 161/Mammalian Target of Rapamycin Signaling Pathway in Triple Negative Breast Cancer Cells.

Triple negative breast cancer (TNBC) is one of the leading causes of cancer death in the world and lacks an effective targeted therapy. G-protein-coupled receptor 161 (GPR161) has been demonstrated to perform the functional regulations on TNBC progression and might be a potential new target for TNBC therapy. This study showed the effects of bisdemethoxycurcumin (BDMC) on GPR161 regulation, indicating that BDMC effectively inhibited GPR161 expression and downregulated GPR161-driven signaling. BDMC showed the potent inhibitory effects on TNBC proliferation through suppressing GPR161-mediated mammalian target of rapamycin (mTOR)/70 kDa ribosomal protein S6 kinase (p70S6K) activation. Besides, in this study, we discover the mechanism of GPR161-driven TNBC metastasis, linking to GPR161-mediated twist-related protein 1 (Twist1)/matrix metallopeptidase 9 (MMP9) contributing to the epithelial-mesenchymal transition (EMT). BDMC effectively repressed GPR161-mediated TNBC metastasis via inhibiting Twist1/MMP9-induced EMT. The three-dimensional invasion assay also showed that BDMC significantly inhibited TNBC invasion. The combination treatment of BDMC and rapamycin enhanced the inhibition of TNBC proliferation and metastasis through increasing the blockage of mTOR activation. Furthermore, this study also observed that BDMC activated the caspase 3/9 signaling pathway to induce TNBC apoptosis. Therefore, BDMC could be applicable to anticancer therapy, especially targeting on the GPR161-driven cancer type.

Neurological Soft Signs (NSS) in Census-Based, Decade-Adjusted Healthy Adults, 20 to >70 Years of Age.

Neurological soft signs (NSS) represent minor neurological features and have been widely studied in psychiatric disease. The assessment is easily performed. Quantity and quality may provide useful information concerning the disease course. Mostly, NSS scores differ significantly between patients and controls. However, literature does not give reference values. In this pilot study, we recruited 120 healthy women and men to build a cross-sectional, census-based sample of healthy individuals, aged 20 to >70 years, subdivided in 10-year blocks for a close approach to the human lifeline. Testing for NSS and neurocognitive functioning was performed following the exclusion of mental and severe physical illness. NSS scores increased significantly between ages 50+ and 60+, which was primarily accountable to motor signs. Gender and cognitive functioning were not related to changes of scores. Although the number of individuals is small, study results may lay a foundation for further validation of NSS in healthy individuals.

Comparison of Water Pipes vs Other Modes of Cannabis Consumption and Subsequent Illicit Drug Use in a Longitudinal Cohort of Young Swiss Men.

Importance: There are concerns that the use of water pipes to consume cannabis is associated with increased risks of engaging in more addictive behaviors. Objective: To examine whether consuming cannabis with a water pipe was associated with later consumption of other illicit drugs compared with not using a water pipe. Design, Setting, and Participants: The Cohort Study on Substance Use Risk Factors (C-SURF) was a population-based study, recruiting 5987 Swiss men aged 18 to 25 years from 3 of 6 Swiss Armed Forces recruitment centers (response rate: 79.2%). The baseline assessment (t0) was done from 2010 to 2012, first follow-up (t1) from 2012 to 2014, and second follow-up (t2) from 2016 to 2018. Our sample included men who participated in both t0 and t2 assessments and used cannabis but no other illicit drugs at t0. Data analysis was performed from July 2020 to January 2021. Exposures: Cannabis use frequency and route of administration from self-administered questionnaires completed at t0 and t2. Main Outcomes and Measures: Outcome measures were initiation of illicit drug use and cannabis use disorder, identified by the Cannabis Use Disorder Identification Test. To examine whether water pipe use at t0 was associated with illicit drug use at t2, multivariable logistic regression analysis was performed. Results: Among 1108 Swiss male cannabis users who did not use other illicit drugs at t0, the mean (SD) age was 20 (1.2) years, 617 (55.7%) were from Switzerland's French-speaking region, and 343 (30%) used water pipes to consume cannabis. Water pipe users at t0 were more likely to use other illicit drugs at t2 compared with water pipe nonusers (adjusted odds ratio [aOR], 1.54; 95% CI, 1.10-2.16). The odds of using middle-stage drugs (including stimulants, hallucinogens, and inhaled drugs) at t2 were increased for water pipe users (aOR, 1.61; 95% CI, 1.13-2.29). Water pipe use at t0 was not associated with cannabis use disorder at t2 after adjusting for cannabis use frequency. Conclusions and Relevance: This cohort study's results suggest that, among Swiss young men, water pipe use is associated with other illicit drug use later in life, particularly middle-stage illicit drugs. Preventive programs must focus on the potential of later harm to cannabis users who use water pipes but have not yet started taking other illicit drugs.

Estimation of Viral Aerosol Emissions From Simulated Individuals With Asymptomatic to Moderate Coronavirus Disease 2019.

Importance: Individuals with asymptomatic or mild coronavirus disease 2019 (COVID-19) have been reported to frequently transmit the disease even without direct contact. The severe acute respiratory syndrome coronavirus 2 has been found at very high concentrations in swab and sputum samples from such individuals. Objective: To estimate the virus levels released from individuals with asymptomatic to moderate COVID-19 into different aerosol sizes by normal breathing and coughing, and to determine what exposure could result from this in a room shared with such individuals. Design, Setting, and Participants: This mathematical modeling study combined the size-distribution of exhaled breath microdroplets for coughing and normal breathing with viral swab and sputum concentrations as approximation for lung lining liquid to obtain an estimate of emitted virus levels. Viral data were obtained from studies published as of May 20, 2020. The resulting emission data fed a single-compartment model of airborne concentrations in a room of 50 m3, the size of a small office or medical examination room. Main Outcomes and Measures: Modeling was used to estimate the viral load emitted by individuals breathing normally or coughing, and the concentrations expected in the simulated room at different ventilation rates. Results: The mean estimated viral load in microdroplets emitted by simulated individuals while breathing regularly was 0.0000049 copies/cm3, with a range of 0.0000000049 to 0.637 copies/cm3. The corresponding estimates for simulated coughing individuals were a mean of 0.277 copies/cm3 per cough, with a range of 0.000277 to 36 030 copies/cm3 per cough. The estimated concentrations in a room with an individual who was coughing frequently were very high, with a maximum of 7.44 million copies/m3 from an individual who was a high emitter. However, regular breathing from an individual who was a high emitter was modeled to result in lower room concentrations of up to 1248 copies/m3. Conclusions and Relevance: In this modeling study, breathing and coughing were estimated to release large numbers of viruses, ranging from thousands to millions of virus copies per cubic meter in a room with an individual with COVID-19 with a high viral load, depending on ventilation and microdroplet formation process. The estimated infectious risk posed by a person with typical viral load who breathes normally was low. The results suggest that only few people with very high viral load pose an infection risk in poorly ventilated closed environments. These findings suggest that strict respiratory protection may be needed when there is a chance to be in the same small room with an individual, whether symptomatic or not, especially for a prolonged period.

Social cohesion, depression, and substance use severity among young men: Cross-sectional and longitudinal analyses from a Swiss cohort.

INTRODUCTION: Social cohesion, depression, and problematic substance use are intertwined and poorly understood.This study aimed to examine cross-sectional and longitudinal associations between social cohesion, depression and problematic substance use amongyoung men, age 21-25. METHODS: We used 2nd wave (t1, 2012-2014, N = 6020) and 3rd wave (t2, 2016-2018) data from the on-going Swiss CohortStudy on Substance Use Risk Factors (C-SURF), assessing social cohesion, depression, and severity of alcohol, nicotine and cannabis use during both waves. Structural Equation Models (SEMs) were employed to examine pathways in both waves under the framework of longitudinal analysis. RESULTS: Social cohesion was directly associated with depression and problem nicotine and cannabis use and indirectly associated with problem alcohol, nicotine and cannabis use through depression at both t1 and t2. Social cohesion exerted direct effects on nicotine use and cannabis use severity, but not on alcohol use severity. Social cohesion had indirect effects on problem use of all three substances, mediated via depression. The predictive direction was from depression to substance use, rather than vice versa. CONCLUSIONS: Higher social cohesion at an early age appears to protect young males from depression and problematic substance use later in life. However, once problematic substance use is established, the direct effect of social cohesion diminishes and is mediated through personal depression. Therefore, promoting a more cohesiveneighborhood in childhood or adolescenthood could play an important role preventing depression and more severe substance use behaviors.

Effects of short- and long-term exposures to particulate matter on inflammatory marker levels in the general population.

The effect of particulate matter (PM) on health increases with exposure duration but the change from short to longer term is not well studied. We examined the exposure to PM smaller 10 µm (PM10) from short to longer duration and their associations with levels of inflammatory markers in the population-based CoLaus cohort in Lausanne, Switzerland. Baseline and follow-up CoLaus data were used to study the associations between PM10 exposure and inflammatory markers, including the high-sensitivity C-reactive protein (CRP), as well as interleukin 1-beta (IL-1ß), interleukin 6 (IL-6), and tumor-necrosis-factor alpha (TNF-α) using mixed models. Exposure was determined for each participant's home address from hourly air quality simulations at a 5-m resolution. Short-term exposure intervals were 1 day, 1 week, and 1 month prior to the hospital visit (blood withdrawal); long-term exposure intervals were 3 and 6 months prior to the visit. In most time windows, IL-6, IL-1ß, and TNF-α were positively associated with PM10. No significant associations were identified for CRP. Adjusted associations with long-term exposures were stronger and more significant than those for short-term exposures. In stratified models, gender, age, smoking status, and hypertension only led to small modifications in effect estimates, though a few of the estimates for IL-6 and TNF-α became non-significant. In this general adult cohort exposed to relatively low average PM10 levels, clear associations with markers of systemic inflammation were observed. Longer duration of elevated exposure was associated with an exacerbated inflammatory response. This may partially explain the elevated disease risk observed with chronic PM10 exposure. It also suggests that reducing prolonged episodes of high PM exposure may be a strategy to reduce inflammatory risk.

Antrodia cinnamomea induces autophagic cell death via the CHOP/TRB3/Akt/mTOR pathway in colorectal cancer cells.

Antrodia cinnamomea, a well-known traditional medicine used in Taiwan, is a potent anticancer drug for colorectal cancer, but the upstream molecular mechanism of its anticancer effects remains unclear. In this study, A. cinnamomea extracts showed cytotoxicity in HCT116, HT29, SW480, Caco-2 and, Colo205 colorectal cancer cells. Whole-genome expression profiling of A. cinnamomea extracts in HCT116 cells was performed. A. cinnamomea extracts upregulated the expression of the endoplasmic reticulum stress marker CHOP and its downstream gene TRB3. Moreover, dephosphorylation of Akt and mTOR as well as autophagic cell death were observed. Gene expression and autophagic cell death were reversed by the knockdown of CHOP and TRB3. Autophagy inhibition but not apoptosis inhibition reversed A. cinnamomea-induced cell death. Finally, we demonstrated that A. cinnamomea extracts significantly suppressed HCT116 tumour growth in nude mice. Our findings suggest that autophagic cell death via the CHOP/TRB3/Akt/mTOR pathway may represent a new mechanism of anti-colorectal cancer action by A. cinnamomea. A. cinnamomea is a new CHOP activator and potential drug that can be used in colorectal cancer treatment.

Necroptosis promotes autophagy-dependent upregulation of DAMP and results in immunosurveillance.

Programmed necrosis, necroptosis, is considered to be a highly immunogenic activity, often mediated via the release of damage-associated molecular patterns (DAMPs). Interestingly, enhanced macroautophagic/autophagic activity is often found to be accompanied by necroptosis. However, the possible role of autophagy in the immunogenicity of necroptotic death remains largely obscure. In this study, we investigated the possible mechanistic correlation between phytochemical shikonin-induced autophagy and the shikonin-induced necroptosis for tumor immunogenicity. We show that shikonin can instigate RIPK1 (receptor [TNFRSF]-interacting serine-threonine kinase 1)- and RIPK3 (receptor-interacting serine-threonine kinase 3)-dependent necroptosis that is accompanied by enhanced autophagy. Shikonin-induced autophagy can directly contribute to DAMP upregulation. Counterintuitively, among the released and ectoDAMPs, only the latter were shown to be able to activate the cocultured dendritic cells (DCs). Interruption of autophagic flux via chloroquine further upregulated ectoDAMP activity and resultant DC activation. For potential clinical application, DC vaccine preparations treated with tumor cells that were already pretreated with chloroquine and shikonin further enhanced the antimetastatic activity of 4T1 tumors and reduced the effective dosage of doxorubicin. The enhanced immunogenicity and vaccine efficacy obtained via shikonin and chloroquine cotreatment of tumor cells may thus constitute a compelling strategy for developing cancer vaccines via the use of a combinational drug treatment.

Short-term effects of particulate matters on pulse pressure in two general population studies.

OBJECTIVES: To explore the association of short-term exposure to particulate matter with aerodynamic diameters less than 10 µm (PM10) with pulse pressure, SBP, and DBP taking outdoor temperature into account in two large population-based studies in Switzerland. METHODS: We used data from the Bus Santé study including 5605 adults in Geneva and the CoLaus study including 6183 adults in Lausanne. PM10 and meteorological data were measured from fixed monitoring stations. We analyzed the association of short-term exposure to PM10 (on the day of examination visit and up to 7 days before) with pulse pressure, SBP, and DBP by linear regression, controlling for potential confounders and effect modifiers. RESULTS: Average PM10 levels were 22.4 µg/m in Geneva and 31.7 µg/m in Lausanne. In adjusted models, for each 10 µg/m increase in 7-day PM10 average, pulse pressure and SBP increased by 0.583 (95% confidence interval, 0.296-0.870) mmHg and 0.490 (0.056-0.925) mmHg in Geneva, and 0.183 (0.017-0.348) mmHg and 0.036 (0.042-0.561) mmHg in Lausanne, respectively. Stronger associations of pulse pressure and SBP with PM10 were observed when outdoor temperature was above 5°C. CONCLUSION: Positive associations of pulse pressure and SBP with short-term exposure to PM10 were found and replicated in the Swiss adult population. Our results suggest that even low levels of air pollution may substantially impact cardiovascular risk in the general population.

Seasonal variation of overall and cardiovascular mortality: a study in 19 countries from different geographic locations.

BACKGROUND: Cardiovascular diseases (CVD) mortality has been shown to follow a seasonal pattern. Several studies suggested several possible determinants of this pattern, including misclassification of causes of deaths. We aimed at assessing seasonality in overall, CVD, cancer and non-CVD/non-cancer mortality using data from 19 countries from different latitudes. METHODS AND FINDINGS: Monthly mortality data were compiled from 19 countries, amounting to over 54 million deaths. We calculated ratios of the observed to the expected numbers of deaths in the absence of a seasonal pattern. Seasonal variation (peak to nadir difference) for overall and cause-specific (CVD, cancer or non-CVD/non-cancer) mortality was analyzed using the cosinor function model. Mortality from overall, CVD and non-CVD/non-cancer showed a consistent seasonal pattern. In both hemispheres, the number of deaths was higher than expected in winter. In countries close to the Equator the seasonal pattern was considerably lower for mortality from any cause. For CVD mortality, the peak to nadir differences ranged from 0.185 to 0.466 in the Northern Hemisphere, from 0.087 to 0.108 near the Equator, and from 0.219 to 0.409 in the Southern Hemisphere. For cancer mortality, the seasonal variation was nonexistent in most countries. CONCLUSIONS: In countries with seasonal variation, mortality from overall, CVD and non-CVD/non-cancer show a seasonal pattern with mortality being higher in winter than in summer. Conversely, cancer mortality shows no substantial seasonality.

Physicochemical and biological characterization of single-walled and double-walled carbon nanotubes in biological media.

To study the toxicity of nanoparticles under relevant conditions, it is important to reproducibly disperse nanoparticles in biological media in in vitro and in vivo studies. Here, single-walled nanotubes (SWNTs) and double-walled nanotubes (DWNTs) were physicochemically and biologically characterized when dispersed in phosphate-buffered saline (PBS) and bovine serum albumin (BSA). BSA-SWNT/DWNT interaction resulted in a reduction of aggregation and an increase in particle stabilization. Based on the protein sequence coverage and protein binding results, DWNTs exhibited higher protein binding than SWNTs. SWNT and DWNT suspensions in the presence of BSA increased interleukin-6 (IL-6) levels and reduced tumor necrosis factor-alpha (TNF-α) levels in A549 cells as compared to corresponding samples in the absence of BSA. We next determined the effects of SWNTs and DWNTs on pulmonary protein modification using bronchoalveolar lavage fluid (BALF) as a surrogate collected form BALB/c mice. The BALF proteins bound to SWNTs (13 proteins) and DWNTs (11 proteins), suggesting that these proteins were associated with blood coagulation pathways. Lastly, we demonstrated the importance of physicochemical and biological alterations of SWNTs and DWNTs when dispersed in biological media, since protein binding may result in the misinterpretation of in vitro results and the activation of protein-regulated biological responses.

Short-term increase in particulate matter blunts nocturnal blood pressure dipping and daytime urinary sodium excretion.

Short-term exposure to ambient particulate matter with aerodynamic diameters<10 µm were found to be positively associated with blood pressure. Yet, little information exists regarding the association between particles and circadian rhythm of blood pressure. Hence, we analyzed the association of exposure to particulate matter with aerodynamic diameters<10 µm on the day of examination and ≤7 days before with ambulatory blood pressure and with sodium excretion in 359 adults from the general population using multiple linear regression. After controlling for potential confounders, a 10-µg/m3 increase in particulate matter with aerodynamic diameters<10 µm levels was associated with nighttime systolic blood pressure (ß=1.32 mm Hg 95% CI, 0.06-2.58 mm Hg at lag 0; P=0.04), nighttime diastolic blood pressure (0.72 mm Hg 95% CI, 0.03-1.42 mm Hg at lag 2; P=0.04), nocturnal systolic blood pressure dipping (-0.96 mm Hg 95% CI, -1.89 to -0.03 mm Hg at lag 0; P=0.044), and daytime urinary sodium excretion (-0.05 log-mmol/min 95% CI, -0.10 to -0.01 log-mmol/min at lag 0; P=0.027) but not with nighttime sodium excretion. The associations with blood pressure rapidly diminished with increasing lag days, and the associations with daytime sodium excretion were maximal with particulate matter with aerodynamic diameters<10 µm in exposures 2 to 5 days before. The associations of short-term increases in particulate matter with aerodynamic diameters<10 µm with higher nighttime blood pressure and blunted systolic blood pressure dipping were preceded by associations with reduced ability of the kidney to excrete sodium during daytime. The underlying mechanism linking air pollution to increased cardiovascular risk may include disturbed circadian rhythms of renal sodium handling and blood pressure.

Effects of particulate matter on inflammatory markers in the general adult population.

BACKGROUND: Particulate air pollution is associated with increased risk of cardiovascular disease and stroke. Although the precise mechanisms underlying this association are still unclear, the induction of systemic inflammation following particle inhalation represents a plausible mechanistic pathway. METHODS: We used baseline data from the CoLaus Study including 6183 adult participants residing in Lausanne, Switzerland. We analyzed the association of short-term exposure to PM(10) (on the day of examination visit) with continuous circulating serum levels of high-sensitive C-reactive protein (hs-CRP), interleukin 1-beta (IL-1ß), interleukin 6 (IL-6), and tumor-necrosis-factor alpha (TNF-α) by robust linear regressions, controlling for potential confounding factors and assessing effect modification. RESULTS: In adjusted analyses, for every 10 µg/m(3) elevation in PM(10), IL-1ß increased by 0.034 (95 % confidence interval, 0.007-0.060) pg/mL, IL-6 by 0.036 (0.015-0.057) pg/mL, and TNF-α by 0.024 (0.013-0.035) pg/mL, whereas no significant association was found with hs-CRP levels. CONCLUSIONS: Short-term exposure to PM(10) was positively associated with higher levels of circulating IL-1ß, IL-6 and TNF-α in the adult general population. This positive association suggests a link between air pollution and cardiovascular risk, although further studies are needed to clarify the mechanistic pathway linking PM(10) to cardiovascular risk.

Office workers' sick building syndrome and indoor carbon dioxide concentrations.

This study attempted to determine whether any association exists between sick building syndrome (SBS) and indoor carbon dioxide (CO(2)) concentrations. We evaluated SBS among 111 office workers in August and November 2003. The environmental conditions in the office, including CO(2) concentrations, temperature, relative humidity, and fine particulate matter (PM(2.5)), were continuously monitored. The most prevalent symptoms of the five SBS groups were eye irritation and nonspecific and upper respiratory symptoms. The generalized estimating equation (GEE) models show that workers exposed to indoor CO(2) levels greater than 800 ppm were likely to report more eye irritation or upper respiratory symptoms.

Traffic-related air pollution and cardiovascular mortality in central Taiwan.

In this study, the relationship between cardiovascular mortality and traffic-related air pollutants (NO(2), CO, PM(10), and six volatile organic compounds (VOCs), propane, iso-butane, propylene, benzene, meta-, para-, and ortho-xylenes) was investigated. The concentrations of NO(2), PM(10) and CO from 1993 to 2006 were measured at a fixed-site air monitoring station, and VOC data from 2003 to 2006 were obtained from a photochemical assessment monitoring site in an urban area in central Taiwan. Outcome variables were data on mortality due to cardiovascular diseases (ICD-9-CM 410-411, 414, 430-437) from 1993 to 2006. Cardiovascular mortality averaged 1.5 cases, ranging between 0 and 9 cases per day. Daily air pollution levels ranged from 0.5 to 80.5ppb for NO(2) and from 0.1 to 3.8ppm for CO. From the subset of data from 2003 to 2006, daily average values ranged from 0.6 to 17.5ppb for propane, 0.3 to 6.7ppb for iso-butane, 0.3 to 6.7ppb for propylene, 0.2 to 3.8ppb for benzene, 0.3 to 26.0ppb for m,p-xylene, and 0.02 to 7.6ppb for o-xylene. Poisson generalized additive model was used to estimate the effects of elevated air pollutant levels on daily mortality, adjusting for meteorological conditions and temporal trends. Single-pollutant model showed that cardiovascular mortality was significantly associated with NO(2) lagged 2 days, and with propane, iso-butane, and benzene lagged 0 day. The relative risk for an interquartile range increase in air pollutant levels was 1.053 for NO(2), 1.064 for propane, 1.055 for iso-butane, and 1.055 for benzene. In conclusion, daily cardiovascular mortality showed association with data on acute exposure to traffic air pollutants in Taichung, which is an important factor to consider in studying cardiovascular mortality in urban environments.

Comparisons of commuter's exposure to particulate matters while using different transportation modes.

This study compared commuters' exposures to particulate matter (PM) while using motorcycles, cars, buses, and the mass rapid transit (MRT) on the same routes in Taipei, Taiwan. Motorcycle commuters who had the shortest travel time (28.4+/-4.2 min) were exposed to the highest concentrations of PM(10) (112.8+/-38.3 microg/m(3)), PM(2.5) (67.5+/-31.3 microg/m(3)), and PM(1.0) (48.4+/-24.7 microg/m(3)) among four commuting modes. By contrast, car commuters were exposed to the lowest PM concentrations and had the second shortest travel time among them. Motorcycle commuters' high trip-averaged PM concentrations and bus commuters' long commuting time (43.1+/-5.1 min) resulted in their high whole-trip PM exposures. Size fractions of PM were relatively consistent across PM exposures of the four commuting modes with fine particles (PM(2.5)) contributing to 53-60% of PM(10) and submicron particle (PM(1)) contributing to 39-43% of PM(10). Motorcycles idled at traffic lights and bus doors opened at stops increased commuters' PM exposures. Fixed-site monitoring data explained well the variation of whole-trip PM(10) exposure of car (r(2)=0.63) and MRT (r(2)=0.52) commuters, and of whole-trip PM(2.5) exposure of car (r(2)=0.76), MRT (r(2)=0.73) and motorcycle (r(2)=0.64) commuters in regression analyses. The coefficients (slopes) of regression between fixed-site monitoring data and PM(2.5) exposures were less than 1 for car and MRT commuters but greater than 1 for motorcycle commuters. In conclusion, proximity to traffic emissions contributes to a person's high PM exposure during his or her daily commute. This proximity occurs when people use motorcycles on roads and when bus/MRT commuters walk or wait along commuting routes. Fixed-site air monitoring data can under-estimate motorcycle commuters' PM(2.5) exposures but over-estimate car and MRT commuters' PM(2.5) exposures.

A study of ground-level ozone pollution, ozone precursors and subtropical meteorological conditions in central Taiwan.

Hourly concentrations of ozone (O(3)), 55 volatile organic compounds (VOCs, ozone precursors) and nitrogen oxides (NOx) were measured at an upwind urban site, a downwind suburban site, and a rural site in central Taiwan, from January 2003 to December 2006. VOC and NOx mean concentrations showed a gradient from high to low across the urban (56 ppb and 34 ppb), suburban (38 ppb and 27 ppb) and rural sites (25 ppb and 21 ppb) but a reverse gradient in ozone across these sites (24, 27, and 29 ppb, respectively). Although there was about twice the difference in VOC concentrations between the urban and rural sites, nearly 65% ozone formation potential was contributed to by the same 9 VOCs. Seasonal patterns showed peak ozone levels in autumn and minima in summer at the urban site, but minima in winter at the downwind suburban and rural sites. Ozone precursor levels, on the other hand, were lowest in summer and highest in winter. The diurnal pattern showed that ozone levels peaked one hour later at the rural site than at the urban site. The ethylbenzene to m,p-xylene ratio, an indicator of the age of the air mass, increased from 0.4 at the urban site to 0.6 at the suburban site and 0.8 at the rural site during daily peak ozone times. This finding suggests the transport of ozone and precursors from upwind to downwind producing elevated ozone levels in the suburban and rural areas. Ozone episodes occurred mostly in days with a mean midday UV index of 6.5 (1 UV index=100 J m(-2)) and wind speed at 1.3 m s(-1) at all three sites.