The contributions to long-term health-relevant particulate matter at the UK EMEP supersites between 2010 and 2013: Quantifying the mitigation challenge

Human health burdens associated with long-term exposure to particulate matter (PM) are substantial. The metrics currently recommended by the World Health Organization for quantification of long-term health-relevant PM are the annual average PM₁₀ and PM_2.5 mass concentrations, with no low concentration threshold. However, within an annual average, there is substantial variation in the composition of PM associated with different sources. To inform effective mitigation strategies, therefore, it is necessary to quantify the conditions that contribute to annual average PM₁₀ and PM_2.5 (rather than just short-term episodic concentrations). PM₁₀, PM_2.5, and speciated water-soluble inorganic, carbonaceous, heavy metal and polycyclic aromatic hydrocarbon components are concurrently measured at the two UK European Monitoring and Evaluation Programme (EMEP) ‘supersites’ at Harwell (SE England) and Auchencorth Moss (SE Scotland). In this work, statistical analyses of these measurements are integrated with air-mass back trajectory data to characterise the ‘chemical climate’ associated with the long-term health-relevant PM metrics at these sites. Specifically, the contributions from different PM concentrations, months, components and geographic regions are detailed. The analyses at these sites provide policy-relevant conclusions on mitigation of (i) long-term health-relevant PM in the spatial domain for which these sites are representative, and (ii) the contribution of regional background PM to long-term health-relevant PM.At Harwell the mean (± 1 sd) 2010–2013 annual average concentrations were PM₁₀ = 16.4 ± 1.4 μg m^− 3 and PM_2.5 = 11.9 ± 1.1 μg m^− 3 and at Auchencorth PM₁₀ = 7.4 ± 0.4 μg m^− 3 and PM_2.5 = 4.1 ± 0.2 μg m^− 3. The chemical climate state at each site showed that frequent, moderate hourly PM₁₀ and PM_2.5 concentrations (defined as approximately 5–15 μg m^− 3 for PM₁₀ and PM_2.5 at Harwell and 5–10 μg m^− 3 for PM₁₀ at Auchencorth) determined the magnitude of annual average PM₁₀ and PM_2.5 to a greater extent than the relatively infrequent high, episodic PM₁₀ and PM_2.5 concentrations. These moderate PM₁₀ and PM_2.5 concentrations were derived across the range of chemical components, seasons and air-mass pathways, in contrast to the highest PM concentrations which tended to associate with specific conditions. For example, the largest contribution to moderate PM₁₀ and PM_2.5 concentrations – the secondary inorganic aerosol components, specifically NO₃⁻ – were accumulated during the arrival of trajectories traversing the spectrum of marine, UK, and continental Europe areas. Mitigation of the long-term health-relevant PM impact in the regions characterised by these two sites requires multilateral action, across species (and hence source sectors), both nationally and internationally; there is no dominant determinant of the long-term PM metrics to target.     

Saharan dust,particulate matter and cause-specific mortality: A case–crossover study in Barcelona (Spain)

BackgroundStudies measuring health effects of Saharan dust based on large particulate matter (PM) fraction groups may be masking some effects. Long distant transport reduces the amount of heavier and larger particles in the Saharan air masses increasing the relative contribution of smaller particles that may be more innocuous. This study investigates the association between different PM fractions and daily mortality during Saharan and non-Saharan days in Barcelona, Spain.MethodsWe collected daily PM₁, PM_2.5–1 and PM_10–2.5 fractions, and cause-specific mortality (cardiovascular, respiratory and cerebrovascular) between March 2003 and December 2007. Changes of effects between Saharan and non-Saharan dust days were assessed using a time-stratified case–crossover design.ResultsDuring non-Saharan dust days we found statistically significant (p < 0.05) effects of PM_10–2.5 for cardiovascular (odds ratio for increase of an interquartile range, OR = 1.033, 95% confidence interval: 1.006–1.060) and respiratory mortality (OR = 1.044, 95% CI: 1.001–1.089). During Saharan dust days strongest cardiovascular effects were found for the same fraction (OR = 1.085, 95% CI: 1.017–1.158) with an indication of effect modification (p = 0.111). Effects of PM_2.5–1 during Saharan dust days were about the double than in non-dust days for cardiovascular and respiratory mortality, but these differences were not statistically significant.ConclusionOur results using independent fractions of PMs provide further evidence that the effects of short-term exposure to PM during Saharan dust days are associated with both cardiovascular and respiratory mortality. A better understanding of which of the different PM size fractions brought by Saharan dust is more likely to accelerate adverse effects may help better understand mechanisms of toxicity.     

Associations between ultrafine and fine particles and mortality in five central European cities — Results from the UFIREG study

BackgroundEvidence on health effects of ultrafine particles (UFP) is still limited as they are usually not monitored routinely. The few epidemiological studies on UFP and (cause-specific) mortality so far have reported inconsistent results.ObjectivesThe main objective of the UFIREG project was to investigate the short-term associations between UFP and fine particulate matter (PM) < 2.5 μm (PM_2.5) and daily (cause-specific) mortality in five European Cities. We also examined the effects of PM < 10 μm (PM₁₀) and coarse particles (PM_2.5–10).MethodsUFP (20–100 nm), PM and meteorological data were measured in Dresden and Augsburg (Germany), Prague (Czech Republic), Ljubljana (Slovenia) and Chernivtsi (Ukraine). Daily counts of natural and cardio-respiratory mortality were collected for all five cities. Depending on data availability, the following study periods were chosen: Augsburg and Dresden 2011–2012, Ljubljana and Prague 2012–2013, Chernivtsi 2013–March 2014. The associations between air pollutants and health outcomes were assessed using confounder-adjusted Poisson regression models examining single (lag 0–lag 5) and cumulative lags (lag 0–1, lag 2–5, and lag 0–5). City-specific estimates were pooled using meta-analyses methods.ResultsResults indicated a delayed and prolonged association between UFP and respiratory mortality (9.9% [95%-confidence interval: − 6.3%; 28.8%] increase in association with a 6-day average increase of 2750 particles/cm³ (average interquartile range across all cities)). Cardiovascular mortality increased by 3.0% [− 2.7%; 9.1%] and 4.1% [0.4%; 8.0%] in association with a 12.4 μg/m³ and 4.7 μg/m³ increase in the PM_2.5- and PM_2.5–10-averages of lag 2–5.ConclusionsWe observed positive but not statistically significant associations between prolonged exposures to UFP and respiratory mortality, which were independent of particle mass exposures. Further multi-centre studies are needed investigating several years to produce more precise estimates on health effects of UFP.     

Combustion particles emitted during church services: Implications for human respiratory health

Burning candles and incense generate particulate matter (PM) that produces poor indoor air quality and may cause human pulmonary problems. This study physically characterised combustion particles collected in a church during services. In addition, the emissions from five types of candles and two types of incense were investigated using a combustion chamber. The plasmid scission assay was used to determine the oxidative capacities of these church particles. The corresponding risk factor (CRf) was derived from the emission factor (Ef) and the oxidative DNA damage, and used to evaluate the relative respiratory exposure risks. Real-time PM measurements in the church during candle–incense burning services showed that the levels (91.6 μg/m³ for PM₁₀; 38.9 μg/m³ for PM_2.5) exceeded the European Union (EU) air quality guidelines. The combustion chamber testing, using the same environmental conditions, showed that the incense Ef for both PM₁₀ (490.6–587.9 mg/g) and PM_2.5 (290.1–417.2 mg/g) exceeded that of candles; particularly the PM_2.5 emissions. These CRf results suggested that the exposure to significant amounts of incense PM could result in a higher risk of oxidative DNA adducts (27.4–32.8 times) than tobacco PM. The generation and subsequent inhalation of PM during church activities may therefore pose significant risks in terms of respiratory health effects.     

Air pollution exposure and telomere length in highly exposed subjects in Beijing,China: A repeated-measure study

BackgroundAmbient particulate matter (PM) exposure has been associated with short- and long-term effects on cardiovascular disease (CVD). Telomere length (TL) is a biomarker of CVD risk that is modified by inflammation and oxidative stress, two key pathways for PM effects. Whether PM exposure modifies TL is largely unexplored.ObjectivesTo investigate effects of PM on blood TL in a highly-exposed population.MethodsWe measured blood TL in 120 blood samples from truck drivers and 120 blood samples from office workers in Beijing, China. We measured personal PM_2.5 and Elemental Carbon (EC, a tracer of traffic particles) using light-weight monitors. Ambient PM₁₀ was obtained from local monitoring stations. We used covariate-adjusted regression models to estimate percent changes in TL per an interquartile-range increase in exposure.ResultsCovariate-adjusted TL was higher in drivers (mean = 0.87, 95%CI: 0.74; 1.03) than in office workers (mean = 0.79, 95%CI: 0.67; 0.93; p = 0.001). In all participants combined, TL increased in association with personal PM_2.5 (+ 5.2%, 95%CI: 1.5; 9.1; p = 0.007), personal EC (+ 4.9%, 95%CI: 1.2; 8.8; p = 0.01), and ambient PM₁₀ (+ 7.7%, 95%CI: 3.7; 11.9; p < 0.001) on examination days. In contrast, average ambient PM₁₀ over the 14 days before the examinations was significantly associated with shorter TL (− 9.9%, 95%CI: − 17.6; − 1.5; p = 0.02).ConclusionsShort-term exposure to ambient PM is associated with increased blood TL, consistent with TL roles during acute inflammatory responses. Longer exposures may shorten TL as expected after prolonged pro-oxidant exposures. The observed TL alterations may participate in the biological pathways of short- and long-term PM effects.     

Traffic-related air pollution and hyperactivity/inattention,dyslexia and dyscalculia in adolescents of the German GINIplus and LISAplus birth cohorts

BackgroundFew studies have examined the link between air pollution exposure and behavioural problems and learning disorders during late childhood and adolescence.ObjectivesTo determine whether traffic-related air pollution exposure is associated with hyperactivity/inattention, dyslexia and dyscalculia up to age 15 years using the German GINIplus and LISAplus birth cohorts (recruitment 1995–1999).MethodsHyperactivity/inattention was assessed using the German parent-completed (10 years) and self-completed (15 years) Strengths and Difficulties Questionnaire. Responses were categorized into normal versus borderline/abnormal. Parent-reported dyslexia and dyscalculia (yes/no) at age 10 and 15 years were defined using parent-completed questionnaires. Individual-level annual average estimates of nitrogen dioxide (NO₂), particulate matter (PM)₁₀ mass, PM_2.5 mass and PM_2.5 absorbance concentrations were assigned to each participant's birth, 10 year and 15 year home address. Longitudinal associations between the air pollutants and the neurodevelopmental outcomes were assessed using generalized estimation equations, separately for both study areas, and combined in a random-effects meta-analysis. Odds ratios and 95% confidence intervals are given per interquartile range increase in pollutant concentration.ResultsThe prevalence of abnormal/borderline hyperactivity/inattention scores and parental-reported dyslexia and dyscalculia at 15 years of age was 12.9%, 10.5% and 3.4%, respectively, in the combined population (N = 4745). In the meta- analysis, hyperactivity/inattention was associated with PM_2.5 mass estimated to the 10 and 15 year addresses (1.12 [1.01, 1.23] and 1.11 [1.01, 1.22]) and PM_2.5 absorbance estimated to the 10 and 15 year addresses (1.14 [1.05, 1.25] and 1.13 [1.04, 1.23], respectively).ConclusionsWe report associations suggesting a potential link between air pollution exposure and hyperactivity/inattention scores, although these findings require replication.     

Associations between size-fractionated particulate air pollution and blood pressure in a panel of type II diabetes mellitus patients

Little is known regarding how the size distribution of particulate matter (PM) air pollution influences its effect on blood pressure (BP), especially among patients with diabetes. The objective of this study was to explore the short-term associations between size-fractionated PM and BP among diabetes patients. We scheduled 6 repeated BP examinations every 2 weeks from 13 April 2013 to 30 June 2013 in a panel of 35 type 2 diabetes mellitus patients recruited from an urban community in Shanghai, China. We measured real-time PM concentrations in the size range of 0.25 to 10 μm. We used linear mixed-effect models to examine the short-term association of size-fractionated PM and BP after controlling for individual characteristics, mean temperature, relative humidity, day of the week, years with diabetes and use of antihypertensive medication. The association with systolic BP and pulse pressure strengthened with decreasing diameter. The size fractions with the strongest associations were 0.25 to 0.40 μm for number concentrations and ≤ 2.5 μm for mass concentrations. Furthermore, these effects occurred immediately even after 0–2 h and lasted for up to 48 h following exposure. An interquartile range increase in 24-h average number concentrations of PM_0.25–0.40 was associated with increases of 3.61 mm Hg in systolic BP and 2.96 mm Hg in pulse pressure. Females, patients younger than 65 years of age and patients without antihypertensive treatment were more susceptible to these effects. Our results revealed important size and temporal patterns of PM in elevating BP among diabetes patients in China.     

Recent versus chronic exposure to particulate matter air pollution in association with neurobehavioral performance in a panel study of primary schoolchildren

Children's neuropsychological abilities are in a developmental stage. Recent air pollution exposure and neurobehavioral performance are scarcely studied. In a panel study, we repeatedly administered to each child the following neurobehavioral tests: Stroop Test (selective attention) and Continuous Performance Test (sustained attention), Digit Span Forward and Backward Tests (short-term memory), and Digit-Symbol and Pattern Comparison Tests (visual information processing speed). At school, recent inside classroom particulate matter ≤ 2.5 or 10 μm exposure (PM_2.5, PM₁₀) was monitored on each examination day. At the child's residence, recent (same day up to 2 days before) and chronic (365 days before examination) exposures to PM_2.5, PM₁₀ and black carbon (BC) were modeled. Repeated neurobehavioral test performances (n = 894) of the children (n = 310) reflected slower Stroop Test (p = 0.05) and Digit-Symbol Test (p = 0.01) performances with increasing recent inside classroom PM_2.5 exposure. An interquartile range (IQR) increment in recent residential outdoor PM_2.5 exposure was associated with an increase in average latency of 0.087 s (SE: ± 0.034; p = 0.01) in the Pattern Comparison Test. Regarding chronic exposure at residence, an IQR increment of PM_2.5 exposure was associated with slower performances in the Continuous Performance (9.45 ± 3.47 msec; p = 0.007) and Stroop Tests (59.9 ± 26.5 msec; p = 0.02). Similar results were obtained for PM₁₀ exposure. In essence, we showed differential neurobehavioral changes robustly and adversely associated with recent or chronic ambient exposure to PM air pollution at residence, i.e., with recent exposure for visual information processing speed (Pattern Comparison Test) and with chronic exposure for sustained and selective attention.     

Long-term effects of elemental composition of particulate matter on inflammatory blood markers in European cohorts

BackgroundEpidemiological studies have associated long-term exposure to ambient particulate matter with increased mortality from cardiovascular and respiratory disorders. Systemic inflammation is a plausible biological mechanism behind this association. However, it is unclear how the chemical composition of PM affects inflammatory responses.ObjectivesTo investigate the association between long-term exposure to elemental components of PM and the inflammatory blood markers high-sensitivity C-reactive protein (hsCRP) and fibrinogen as part of the European ESCAPE and TRANSPHORM multi-center projects.MethodsIn total, 21,558 hsCRP measurements and 17,428 fibrinogen measurements from cross-sections of five and four cohort studies were available, respectively. Residential long-term concentrations of particulate matter < 10 μm (PM₁₀) and < 2.5 μm (PM_2.5) in diameter and selected elemental components (copper, iron, potassium, nickel, sulfur, silicon, vanadium, zinc) were estimated based on land-use regression models. Associations between components and inflammatory markers were estimated using linear regression models for each cohort separately. Cohort-specific results were combined using random effects meta-analysis. As a sensitivity analysis the models were additionally adjusted for PM mass.ResultsA 5 ng/m³ increase in PM_2.5 copper and a 500 ng/m³ increase in PM₁₀ iron were associated with a 6.3% [0.7; 12.3%] and 3.6% [0.3; 7.1%] increase in hsCRP, respectively. These associations between components and fibrinogen were slightly weaker. A 10 ng/m³ increase in PM_2.5 zinc was associated with a 1.2% [0.1; 2.4%] increase in fibrinogen; confidence intervals widened when additionally adjusting for PM_2.5.ConclusionsLong-term exposure to transition metals within ambient particulate matter, originating from traffic and industry, may be related to chronic systemic inflammation providing a link to long-term health effects of particulate matter.     

Measurement and health risk assessment of PM2.5, flame retardants,carbonyls and black carbon in indoor and outdoor air in kindergartens in Hong Kong

Indoor air pollution is closely related to children's health. Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) transmitted through indoor PM_2.5 and dust, along with carbonyl compounds and black carbon (BC) aerosol were analysed in five Hong Kong kindergartens. The results showed that 60% of the median PM_2.5 levels (1.3 × 10¹ to 2.9 × 10¹ μg/m³ for indoor; 9.5 to 8.8 × 10¹ μg/m³ for outdoor) in the five kindergartens were higher than the guidelines set by the World Health Organization (2.5 × 10¹ μg/m³). Indoor PM_2.5 mass concentrations were correlated with outdoor PM_2.5 in four of the kindergartens. The PBDEs (0.10–0.64 ng/m³ in PM_2.5; 0.30–2.0 × 10² ng/g in dust) and DP (0.05–0.10 ng/m³ in PM_2.5; 1.3–8.7 ng/g in dust) were detected in 100% of the PM_2.5 and dust samples. Fire retardant levels in the air were not correlated with the levels of dust in this study. The median BC concentrations varied by > 7-fold from 8.8 × 10² ng/m^− 3 to 6.7 × 10³ ng/m^− 3 and cooking events might have caused BC concentrations to rise both indoors and outdoors. The total concentrations of 16 carbonyls ranged from 4.7 × 10¹ μg/m³ to 9.3 × 10¹ μg/m³ indoors and from 1.9 × 10¹ μg/m³ to 4.3 × 10¹ μg/m³ outdoors, whilst formaldehyde was the most abundant air carbonyl. Indoor carbonyl concentrations were correlated with outdoor carbonyls in three kindergartens. The health risk assessment showed that hazard indexes (HIs) HIs of non-cancer risks from PBDEs and DPs were all lower than 0.08, whilst non-cancer HIs of carbonyl compounds ranged from 0.77 to 1.85 indoors and from 0.50 to 0.97 outdoors. The human intake of PBDEs and DP through inhalation of PM_2.5 accounted for 78% to 92% of the total intake. The cancer hazard quotients (HQs) of formaldehyde ranged from 4.5E − 05 to 2.1E − 04 indoors and from 1.9E − 05 to 6.2E − 05 outdoors. In general, the indoor air pollution in the five Hong Kong kindergartens might present adverse effects to children, although different schools showed distinct pollution levels, so indoor air quality might be improved through artificial measures. The data will be useful to developing a feasible management protocol for indoor environments.     

Associations among plasma metabolite levels and short-term exposure to PM2.5 and ozone in a cardiac catheterization cohort

RationaleExposure to ambient particulate matter (PM) and ozone has been associated with cardiovascular disease (CVD). However, the mechanisms linking PM and ozone exposure to CVD remain poorly understood.ObjectiveThis study explored associations between short-term exposures to PM with a diameter < 2.5 μm (PM_2.5) and ozone with plasma metabolite concentrations.Methods and resultsWe used cross-sectional data from a cardiac catheterization cohort at Duke University, North Carolina (NC), USA, accumulated between 2001 and 2007. Amino acids, acylcarnitines, ketones and total non-esterified fatty acid plasma concentrations were determined in fasting samples. Daily concentrations of PM_2.5 and ozone were obtained from a Bayesian space-time hierarchical model, matched to each patient's residential address. Ten metabolites were selected for the analysis based on quality criteria and cluster analysis. Associations between metabolites and PM_2.5 or ozone were analyzed using linear regression models adjusting for long-term trend and seasonality, calendar effects, meteorological parameters, and participant characteristics.We found delayed associations between PM_2.5 or ozone and changes in metabolite levels of the glycine-ornithine-arginine metabolic axis and incomplete fatty acid oxidation associated with mitochondrial dysfunction. The strongest association was seen for an increase of 8.1 μg/m³ in PM_2.5 with a lag of one day and decreased mean glycine concentrations (− 2.5% [95% confidence interval: − 3.8%; − 1.2%]).ConclusionsShort-term exposures to ambient PM_2.5 and ozone is associated with changes in plasma concentrations of metabolites in a cohort of cardiac catheterization patients. Our findings might help to understand the link between air pollution and cardiovascular disease.     

Acute respiratory response to traffic-related air pollution during physical activity performance

BackgroundPhysical activity (PA) has beneficial, whereas exposure to traffic related air pollution (TRAP) has adverse, respiratory effects. Few studies, however, have examined if the acute effects of TRAP upon respiratory outcomes are modified depending on the level of PA.ObjectivesThe aim of our study was to disentangle acute effects of TRAP and PA upon respiratory outcomes and assess the impact of participants TRAP pre-exposure.MethodsWe conducted a real-world crossover study with repeated measures of 30 healthy adults. Participants completed four 2-h exposure scenarios that included either rest or intermittent exercise in high- and low-traffic environments. Measures of respiratory function were collected at three time points. Pre-exposure to TRAP was ascertained from land-use-modeled address-attributed values. Mixed-effects models were used to estimate the impact of TRAP and PA on respiratory measures as well as potential effect modifications.ResultsWe found that PA was associated with a statistically significant increases of FEV₁ (48.5 mL, p = 0.02), FEV₁/FVC (0.64%, p = 0.005) and FEF_25–75% (97.8 mL, p = 0.02). An increase in exposure to one unit (1 μg/m³) of PM_coarse was associated with a decrease in FEV₁ (− 1.31 mL, p = 0.02) and FVC (− 1.71 mL, p = 0.01), respectively. On the other hand, for an otherwise equivalent exposure an increase of PA by one unit (1%Heart rate max) was found to reduce the immediate negative effects of particulate matter (PM) upon PEF (PM_2.5, 0.02 L/min, p = 0.047; PM₁₀, 0.02 L/min p = 0.02; PM_coarse, 0.03 L/min, p = 0.02) and the several hours delayed negative effects of PM upon FVC (PM_coarse, 0.11 mL, p = 0.02). The negative impact of exposure to TRAP constituents on FEV₁/FVC and PEF was attenuated in those participants with higher TRAP pre-exposure levels.ConclusionsOur results suggest that associations between various pollutant exposures and respiratory measures are modified by the level of PA during exposure and TRAP pre-exposure of participants.     

Association between long-term exposure to air pollution and mortality in France: A 25-year follow-up study

IntroductionLong-term exposure to air pollution (AP) has been shown to have an impact on mortality in numerous countries, but since 2005 no data exists for France.ObjectivesWe analyzed the association between long-term exposure to air pollution and mortality at the individual level in a large French cohort followed from 1989 to 2013.MethodsThe study sample consisted of 20,327 adults working at the French national electricity and gas company EDF-GDF. Annual exposure to PM₁₀, PM_10–2.5, PM_2.5, NO₂, O₃, SO₂, and benzene was assessed for the place of residence of participants using a chemistry-transport model and taking residential history into account. Hazard ratios were estimated using a Cox proportional-hazards regression model, adjusted for selected individual and contextual risk factors. Hazard ratios were computed for an interquartile range (IQR) increase in air pollutant concentrations.ResultsThe cohort recorded 1967 non-accidental deaths. Long-term exposures to baseline PM_2.5, PM_10-25, NO₂ and benzene were associated with an increase in non-accidental mortality (Hazard Ratio, HR = 1.09; 95% CI: 0.99, 1.20 per 5.9 μg/m³, PM_10-25; HR = 1.09;95% CI: 1.04, 1.15 per 2.2 μg/m³, NO₂: HR = 1.14; 95% CI: 0.99, 1.31 per 19.3 μg/m³ and benzene: HR = 1.10; 95% CI: 1.00, 1.22 per 1.7 μg/m³).The strongest association was found for PM₁₀: HR = 1.14; 95% CI: 1.05, 1.25 per 7.8 μg/m³. PM₁₀, PM_10-25 and SO₂ were associated with non-accidental mortality when using time varying exposure. No significant associations were observed between air pollution and cardiovascular and respiratory mortality.ConclusionLong-term exposure to fine particles, nitrogen dioxide, sulfur dioxide and benzene is associated with an increased risk of non-accidental mortality in France. Our results strengthen existing evidence that outdoor air pollution is a significant environmental risk factor for mortality. Due to the limited sample size and the nature of our study (occupational), further investigations are needed in France with a larger representative population sample.     

Air pollution exposure increases the risk of rheumatoid arthritis: A longitudinal and nationwide study

ObjectiveRheumatoid arthritis (RA) has been associated with inhaled pollutants in several studies, and it is a disease of chronic inflammation. The association between air pollution and the risk of RA remains unclear. Therefore, we conducted this nationwide, retrospective, sex-stratification study to evaluate this association.MethodsWe collected data from the Longitudinal Health Insurance Database (LHID), maintained by the Taiwan Bureau of National Health Insurance, and the Taiwan Air Quality-Monitoring Database (TAQMD), released by the Taiwan Environmental Protection Agency. The TAQMD provides the daily concentrations of particulate matter with the aerodynamic diameter < 2.5 μm (PM_2.5) and nitrogen dioxide (NO₂) from 74 ambient air quality-monitoring stations distributed all over Taiwan during 1998–2010. The LHID and TAQMD were linked according to the residential areas of insurants and the areas where the air quality-monitoring stations were located. A residential area was defined according to the location of the clinic and hospital that treated acute upper respiratory tract infections. The yearly average air pollutant concentrations were categorized into 4 levels based on quartiles. We evaluated the risk of RA in residents exposed to 4 levels of PM_2.5 and NO₂ concentrations.ResultsWe detected an increased risk of RA in participants exposed to PM_2.5 and NO₂. Among four quartiles of NO₂ concentration, namely Q1, Q2, Q3, and Q4, the adjusted hazard ratios (aHRs) in Q2, Q3, and Q4 compared with that in Q1 were 1.07 (95% confidence interval [CI] = 0.76–1.50), 1.63 (95% CI = 1.16–2.31),and 1.49 (95% CI = 1.05–2.12), respectively. Regarding the PM_2.5 concentrations, the aHRs after exposure to the Q2, Q3, and Q4 levels were 1.22 (95% CI = 0.85–1.74), 1.15 (95% CI = 0.82–1.62), and 0.79 (95% CI = 0.53–1.16), respectively.ConclusionThe results of this nationwide study suggest an increased risk of RA in residents exposed to NO₂.     

The mortality effect of ship-related fine particulate matter in the Sydney greater metropolitan region of NSW,Australia

This study investigates the mortality effect of primary and secondary PM_2.5 related to ship exhaust in the Sydney greater metropolitan region of Australia. A detailed inventory of ship exhaust emissions was used to model a) the 2010/11 concentration of ship-related PM_2.5 across the region, and b) the reduction in PM_2.5 concentration that would occur if ships used distillate fuel with a 0.1% sulfur content at berth or within 300 km of Sydney. The annual loss of life attributable to 2010/11 levels of ship-related PM_2.5 and the improvement in survival associated with use of low-sulfur fuel were estimated from the modelled concentrations.In 2010/11, approximately 1.9% of the region-wide annual average population weighted-mean concentration of all natural and human-made PM_2.5 was attributable to ship exhaust, and up to 9.4% at suburbs close to ports. An estimated 220 years of life were lost by people who died in 2010/11 as a result of ship exhaust-related exposure (95% CI_β: 140–290, where CI_β is the uncertainty in the concentration-response coefficient only). Use of 0.1% sulfur fuel at berth would reduce the population weighted-mean concentration of PM_2.5 related to ship exhaust by 25% and result in a gain of 390 life-years over a twenty year period (95% CI_β: 260–520). Use of 0.1% sulfur fuel within 300 km of Sydney would reduce the concentration by 56% and result in a gain of 920 life-years over twenty years (95% CI_β: 600–1200).Ship exhaust is an important source of human exposure to PM_2.5 in the Sydney greater metropolitan region. This assessment supports intervention to reduce ship emissions in the GMR. Local strategies to limit the sulfur content of fuel would reduce exposure and will become increasingly beneficial as the shipping industry expands. A requirement for use of 0.1% sulfur fuel by ships within 300 km of Sydney would provide more than twice the mortality benefit of a requirement for ships to use 0.1% sulfur fuel at berth.     

Exposure to coarse particulate matter during gestation and birth weight in the U.S.

Few studies have explored the relationship between coarse particles (PM_10-2.5) and adverse birth outcomes. We examined associations between gestational exposure of PM_10-2.5 and birth weight. U.S. birth certificates data (1999–2007) were acquired for 8,017,865 births. Gestational and trimester exposures of PM_10-2.5 were estimated using co-located PM₁₀ and PM_2.5 monitors ≤ 35 km from the population-weighted centroid of mothers' residential counties. A linear regression model was applied, adjusted by potential confounders. As sensitivity analyses, we explored alternative PM_10-2.5 estimations, adjustment for PM_2.5, and stratification by regions. Gestational exposure to PM_10-2.5 was associated with 6.6 g (95% Confidence Interval: 5.9, 7.2) lower birth weight per interquartile range increase (7.8 μg/m³) in PM_10-2.5 exposures. All three trimesters showed associations. Under different exposure methods for PM_10-2.5, associations remained consistent but with different magnitudes. Results were robust after adjusting for PM_2.5, and regional analyses showed associations in all four regions with larger estimates in the South. Our results suggest that PM_10-2.5 is associated with birth weight in addition to PM_2.5. Regional heterogeneity may reflect differences in population, measurement error, region-specific emission pattern, or different chemical composition within PM_10-2.5. Most countries do not set health-based standards for PM_10-2.5, but our findings indicate potentially important health effects of PM_10-2.5.     

Estimation of exposure to atmospheric pollutants during pregnancy integrating space–time activity and indoor air levels: Does it make a difference?

Studies of air pollution effects during pregnancy generally only consider exposure in the outdoor air at the home address. We aimed to compare exposure models differing in their ability to account for the spatial resolution of pollutants, space–time activity and indoor air pollution levels. We recruited 40 pregnant women in the Grenoble urban area, France, who carried a Global Positioning System (GPS) during up to 3 weeks; in a subgroup, indoor measurements of fine particles (PM_2.5) were conducted at home (n = 9) and personal exposure to nitrogen dioxide (NO₂) was assessed using passive air samplers (n = 10). Outdoor concentrations of NO₂, and PM_2.5 were estimated from a dispersion model with a fine spatial resolution. Women spent on average 16 h per day at home. Considering only outdoor levels, for estimates at the home address, the correlation between the estimate using the nearest background air monitoring station and the estimate from the dispersion model was high (r = 0.93) for PM_2.5 and moderate (r = 0.67) for NO₂. The model incorporating clean GPS data was less correlated with the estimate relying on raw GPS data (r = 0.77) than the model ignoring space–time activity (r = 0.93). PM_2.5 outdoor levels were not to moderately correlated with estimates from the model incorporating indoor measurements and space–time activity (r = − 0.10 to 0.47), while NO₂ personal levels were not correlated with outdoor levels (r = − 0.42 to 0.03). In this urban area, accounting for space–time activity little influenced exposure estimates; in a subgroup of subjects (n = 9), incorporating indoor pollution levels seemed to strongly modify them.     

A method to derive the relationship between the annual and short-term air quality limits—Analysis using the WHO Air Quality Guidelines for health protection

The World Health Organization (WHO) Air Quality Guidelines (AQG) were launched in 2006, but gaps remain in evidence on health impacts and relationships between short-term and annual AQG needed for health protection. We tested whether relationships between WHO short-term and annual AQG for particulates (PM₁₀ and PM_2.5) and nitrogen dioxide (NO₂) are concordant worldwide and derived the annual limits for sulfur dioxide (SO₂) and ozone (O₃) based on the short-term AQG. We obtained air pollutant data over seven years (2004–2010) in seven cities from Asia-Pacific, North America and Europe. Based on probability distribution concept using maximum as the short-term limit and arithmetic mean as the annual limit, we developed a new method to derive limit value one from another in each paired limits for each pollutant with capability to account for allowable exceedances. We averaged the limit derived each year for each city, then used meta-analysis to pool the limit values in all cities. Pooled mean short-term limit for NO₂ (140.5 μg/m³ [130.6–150.4]) was significantly lower than the WHO AQG of 200 μg/m³ while for PM₁₀ (46.4 μg/m³ [95CI:42.1–50.7]) and PM_2.5 (28.6 μg/m³ [24.5–32.6]) were not significantly different from the WHO AQG of 50 and 25 μg/m³ respectively. Pooled mean annual limits for SO₂ and O₃ were 4.6 μg/m³ [3.7–5.5] and 27.0 μg/m³ [21.7–32.2] respectively. Results were robust in various sensitivity analyses. The distribution relationships between the current WHO short-term and annual AQG are supported by empirical data from seven cities for PM₁₀ and PM_2.5, but not for NO₂. The short-term AQG for NO₂ should be lowered for concordance with the selected annual AQG for health protection.     

Associations of gestational and early life exposures to ambient air pollution with childhood respiratory diseases in Shanghai,China: A retrospective cohort study

BackgroundAssociations of ambient air pollutants with respiratory health are inconsistent.ObjectivesWe analyzed the associations of gestational and early life exposures to air pollutants with doctor-diagnosed asthma, allergic rhinitis, and pneumonia in children.MethodsWe selected 3358 preschool children who did not alter residences after birth from a cross-sectional study in 2011–2012 in Shanghai, China. Parents reported children's respiratory health history, home environment, and family lifestyle behaviors. We collected daily concentrations of sulphur dioxide (SO₂), nitrogen dioxide (NO₂), and particulate matter with an aerodynamic diameter ≤ 10 μm (PM₁₀) during the child's total lifetime (2006–2012) for each district where the children lived. We analyzed the associations using logistic regression models.ResultsAfter adjusting for covariates and the other studied pollutants, we found that exposure to NO₂ (increment of 20 μg/m³) during the first year of life was significantly associated with asthma [odds ratio (OR) = 1.77; 95% confidence interval (CI): 1.29–2.43] and allergic rhinitis (OR = 1.67; 95% CI: 1.07–2.61). Exposure to NO₂ during gestation, the first two and three years, and over total lifetimewas all consistently associated with increased odds of allergic rhinitis. Quartiles of NO₂ concentration during different exposure periods showed a slight dose–response relationship with the studied diseases. These diseases had significant associations with pollutant mixtures that included NO₂, but had no significant association with exposures to SO₂ and PM₁₀ individually or in mixtures.ConclusionsGestational and early life exposures to ambient NO₂ are risk factors for childhood respiratory diseases.     

Exposure to long-term air pollution and road traffic noise in relation to cholesterol: A cross-sectional study

BackgroundExposure to traffic noise and air pollution have both been associated with cardiovascular disease, though the mechanisms behind are not yet clear.ObjectivesWe aimed to investigate whether the two exposures were associated with levels of cholesterol in a cross-sectional design.MethodsIn 1993–1997, 39,863 participants aged 50–64 year and living in the Greater Copenhagen area were enrolled in a population-based cohort study. For each participant, non-fasting total cholesterol was determined in whole blood samples on the day of enrolment. Residential addresses 5-years preceding enrolment were identified in a national register and road traffic noise (L_den) were modeled for all addresses. For air pollution, nitrogen dioxide (NO₂) was modeled at all addresses using a dispersion model and PM_2.5 was modeled at all enrolment addresses using a land-use regression model. Analyses were done using linear regression with adjustment for potential confounders as well as mutual adjustment for the three exposures.ResultsBaseline residential exposure to the interquartile range of road traffic noise, NO₂ and PM_2.5 was associated with a 0.58 mg/dl (95% confidence interval: − 0.09; 1.25), a 0.68 mg/dl (0.22; 1.16) and a 0.78 mg/dl (0.22; 1.34) higher level of total cholesterol in single pollutant models, respectively. In two pollutant models with adjustment for noise in air pollution models and vice versa, the association between air pollution and cholesterol remained for both air pollution variables (NO₂: 0.72 (0.11; 1.34); PM_2.5: 0.70 (0.12; 1.28) mg/dl), whereas there was no association for noise (− 0.08 mg/dl). In three-pollutant models (NO₂, PM_2.5 and road traffic noise), estimates for NO₂ and PM_2.5 were slightly diminished (NO₂: 0.58 (− 0.05; 1.22); PM_2.5: 0.57 (− 0.02; 1.17) mg/dl).ConclusionsAir pollution and possibly also road traffic noise may be associated with slightly higher levels of cholesterol, though associations for the two exposures were difficult to separate.