Coarse particulate matter and emergency ambulance dispatches in Fukuoka, Japan: a time-stratified case-crossover study

Association of outdoor air and noise pollution with unprovoked seizures and new onset epilepsy: A systematic review and meta-analysis

Research has indicated that certain environmental exposures may increase the risk of unprovoked seizures and new onset epilepsy. This study aimed to synthesize the literature that has estimated the associations between short- and long-term exposure to outdoor air and noise pollution and the risk of unprovoked seizures and new onset epilepsy. We searched Embase, MEDLINE, Scopus, Web of Science, BIOSIS Previews, Latin American and Caribbean Health Sciences Literature, Proquest Dissertations and Theses, conference abstracts, and the gray literature and conducted citation tracing in June 2023. Observational and ecological studies assessing the associations of air and noise pollution with unprovoked seizures or new onset epilepsy were eligible. One reviewer extracted summary data. Using fixed and random effects models, we calculated the pooled risk ratios (RRs) for the studies assessing the associations between short-term exposure to air pollution and unprovoked seizures. Seventeen studies were included, 16 assessing the association of air pollution with seizures and one with epilepsy. Eight studies were pooled quantitatively. Ozone (O3; RR = .99, 95% confidence interval [CI] = .99-.99) and nitrogen dioxide (NO2) exposure adjusted for particulate matter (RR = 1.02, 95% CI = 1.01-1.02) on the same day, and carbon monoxide (CO) exposure 2 days prior (RR = 1.12, 95% CI = 1.02-1.22), were associated with seizure risk. A single study of air pollution and epilepsy did not report a significant association. The risk of bias and heterogeneity across studies was moderate or high. Short-term exposure to O3, NO2, and CO may affect the risk of seizures; however, the effect estimates for O3 and NO2 were minimal. Additional research should continue to explore these and the associations between outdoor air pollution and epilepsy and between noise pollution and seizures and epilepsy.

Development and performance evaluation of online monitors for near real-time measurement of total and water-soluble organic carbon in fine and coarse ambient PM

In this study, we developed two online monitors for total organic carbon (TOC) and water-soluble organic carbon (WSOC) measurements in fine (dp < 2.5μm) and coarse (2.5μm < dp < 10μm) particulate matter (PM), respectively. Their performance has been evaluated in laboratory and field tests to demonstrate the feasibility of using these monitors to measure near real-time concentrations, with consideration of their potential for being employed in long-term measurements. The fine PM collection setup was equipped with a versatile aerosol concentration enrichment system (VACES) connected to an aerosol-into-liquid-sampler (AILS), whereas two virtual impactors (VIs) in tandem with a modified BioSampler were used to collect coarse PM. These particle collection setups were in tandem with a Sievers M9 TOC analyzer to read TOC and WSOC concentrations in aqueous samples hourly. The average hourly TOC concentration measured by our developed monitors in fine and coarse PM were 5.17 ± 2.41 and 0.92 ± 0.29 μg/m3, respectively. In addition, our TOC readings showed good agreement and were comparable with those quantified using Sunset Lab EC/OC analyzer operating in parallel as a reference. Furthermore, we conducted field tests to produce diurnal profiles of fine PM-bound WSOC, which can show the effects of ambient temperature on maximum values in the nighttime chemistry of the winter, as well as on increased photochemical activities in afternoon peaks during the summer. According to our experimental campaign, WSOC mean values during the study period (3.07 μg/m3 for the winter and 2.7 μg/m3 for the summer) were in a comparable range with those of earlier studies in Los Angeles. Overall, our results corroborate the performance of our developed monitors in near real-time measurements of TOC and WSOC, which can be employed for future source apportionment studies in Los Angeles and other areas, aiding in understanding the health impacts of different pollution sources.

Different sized particles associated with all-cause and cause-specific emergency ambulance calls: A multicity time-series analysis in China

BACKGROUND

Compared with mortality and hospital admission, emergency ambulance calls (EACs) could be a more accurate outcome indicator to reflect the health effects of short-term air pollution exposure. However, such studies have been scarce, especially on a multicity scale in China.

METHODS

We estimated the associations of different diameter particles [i.e., inhalable particulate matter (PM₁₀), coarse particulate matter (PM_c), and fine particulate matter (PM_2.5)] with EACs for all-cause, cardiovascular, and respiratory diseases in seven Chinese cities. We collected data on EACs and air pollution from 2014 to 2019. We used generalized additive models and random-effects meta-analysis to examine the city-specific and overall associations. Stratified analyses were conducted to examine the effect modifications of gender, age, and season.

RESULTS

Significant associations of PM₁₀ and PM_2.5 with EACs were observed, while the PM_c associations were positive but not statistically significant in most analyses. Specifically, each 10 μg/m³ increase in 2-day moving average concentration of PM₁₀ was associated with a 0.25% [95% confidence interval (CI): 0.04%, 0.47%] increase in all-cause EACs, 0.13% (95% CI: -0.01%, 0.26%) in cardiovascular EACs, and 0.35% (95% CI: 0.04%, 0.66%) in respiratory EACs. The corresponding increases in daily EACs for PM_2.5 were 0.30% (95% CI, 0.03%, 0.57%), 0.13% (95% CI, -0.07%, 0.33%), and 0.46% (95% CI, 0.01%, 0.92%). Season of the year also modifies the association between particulate matter pollution and EACs.

CONCLUSIONS

Short-term exposure to PM₁₀ and PM_2.5 were positively associated with daily all-cause and respiratory-related EACs. The associations were stronger during warm season than cold season. Our findings suggest that the most harmful fraction of particulate matter pollution is PM_2.5, which has important implications for current air quality guidelines and regulations in China.

Relationship between different air pollutants and total and cause-specific emergency ambulance dispatches in Shanghai, China

OBJECTIVE

Air pollutants play a crucial role in human health and disease. Emergency ambulance dispatch data have excellent potential for public and environmental health research. This study aimed at investigating the impact of short-term exposure to air pollutants on the emergency ambulance dispatches.

METHODS

We used data on emergency ambulance dispatches in Shanghai Municipality, China, from April 1, 2016 to December 31, 2017. The association of the daily emergency ambulance dispatches with air pollutants including PM_2.5 (particles ≤ 2.5 μm in aerodynamic diameter), PM₁₀, O₃, NO₂ and SO₂ was analyzed with the use of time-series analyses.

RESULTS

A total of 310,825 emergency ambulance dispatches for acute illness occurred in Shanghai during the study period. An increase in PM_2.5 by 10 μg/m³ at lag1 and lag2 was shown to increase the risk of emergency ambulance dispatches (RR for lag1 = 1.05, 95% CI 1.00-1.11, RR for lag2 = 1.07, 95% CI 1.01-1.12). PM₁₀, NO₂, and SO₂ also showed significant associations with emergency ambulance dispatches in single-pollutant models. Cause-specific analyses showed an elevation in PM_2.5 by 10 μg/m³ was associated with an increased risk of emergency ambulance dispatches related to respiratory diseases on the current day (lag0, RR 1.17, 95% CI 1.01-1.33), while the impact on emergency ambulance dispatches related to other diseases presented 1-3 days later. The other pollutants have the similar trend.

CONCLUSIONS

Our findings show a strong relationship between ambient air pollutants and emergency ambulance dispatches. Our study contributes to the growing body of evidence describing the adverse health effects of ambient air pollution and will benefit ambulance services for early warning and effective ambulatory planning.

Coarse particles (PM2.5-10) and cause-specific hospitalizations in southwestern China: Association, attributable risk and economic costs

The short-term morbidity effects of the coarse particle (diameter in 2.5-10 μm, PM_2.5-10), as well as the corresponding morbidity burden and economic costs, remain understudied, especially in developing countries. This study aimed to examine the associations of PM_2.5-10 with cause-specific hospitalizations in a multi-city setting in southwestern China and assess the attributable risk and economic costs. City-specific associations were firstly estimated using generalized additive models with quasi-poisson distribution to handle over-dispersion, and then combined to obtain the regional average association. City-specific and pooled concentration-response (C-R) associations of PM_2.5-10 with cause-specific hospitalizations were also modeled. Subgroup analyses were performed by age, sex, season and region. The health and economic burden of hospitalizations for multiple outcomes due to PM_2.5-10 were further evaluated. A total of 4,407,601 non-accidental hospitalizations were collected from 678 hospitals. The estimates of percentage change in hospitalizations per 10 μg/m³ increase in PM_2.5-10 at lag01 was 0.68% (95%CI: 0.33%-1.03%) for non-accidental causes, 0.86% (95% CI: 0.36%-1.37%) for circulatory diseases, 1.52% (95% CI: 1.00%-2.05%) for respiratory diseases, 1.08% (95% CI: 0.47%-1.69%) for endocrine diseases, 0.66% (95% CI: 0.12%-1.21%) for nervous system diseases, and 0.84% (95% CI: 0.42%-1.25%) for genitourinary diseases, respectively. The C-R associations of PM_2.5-10 with cause-specific hospitalizations suggested some evidence of nonlinearity, except for endocrine diseases. Meanwhile, the adverse effects were modified by age and season. Overall, about 0.70% (95% CI: 0.35%-1.06%) of non-accidental hospitalizations and 0.78% (95% CI: 0.38%-1.17%) of total hospitalization expenses could be attributed to PM_2.5-10. The largest morbidity burden and economic costs were observed in respiratory diseases. Our findings indicate that PM_2.5-10 exposure may increase the risk of hospitalizations for multiple outcomes, and account for considerable morbidity and economic burden.

Short-term exposure to coarse particulate matter and outpatient visits for cardiopulmonary disease in a Chinese city

Limited studies have been conducted to evaluate the short-term relationships between exposure to coarse particulate matter (PM_2.5-10) and outpatient visits in China. We designed this time-series analysis in a Chinese city Yancheng, to explore the relationship of PM_2.5-10 with outpatient visits for cardiopulmonary diseases. The study period was from 2013 to 2015. A typical generalized additive model was used. We explored the lag patterns by building a series of lag of exposure. We also built two-pollutant models to ascertain the independence of PM_2.5-10. Stratified analyses were applied to compare the season-specific associations. Finally, we pooled the concentration-response (C-R) curves for PM_2.5-10 and outpatient visits. We recorded a daily average of 85 and 43 outpatient visits for cardiovascular and respiratory causes, respectively. PM_2.5-10 exposures of lag 05 day yielded the best estimates for both outcomes. Per 10-μg/m³ increase in PM_2.5-10, there was a 1.69% (95% confidence interval [CI]: 0.68%-2.72%) increase in outpatient visits for respiratory causes, and a 0.85% (95% CI: 0.13%-1.57%) increase for cardiovascular causes. The association kept robust after adjusting for PM_2.5 and O₃, and there were larger associations in warm seasons. The C-R curves had a larger slope for respiratory diseases in relatively lower concentrations (<30 μg/m³), and PM_2.5-10 was positively associated with cardiovascular diseases in higher concentrations (>30 μg/m³). This study indicated significant associations of PM_2.5-10 with cardiopulmonary outpatient visit. Such results may be used for health risk assessment and policy making for particulate air pollution control.

Association between coarse particulate matter (PM10-2.5) and nasopharyngeal carcinoma among Taiwanese men

The nasopharyngeal tract traps mainly coarse particles in inhaled air. Soluble carcinogenic compounds, endotoxins, and trace metals contained in these particles are potential causes of inflammation and oxidative stress which could enhance carcinogenesis. The aim of this study was to determine the association between coarse particulate matter (PM10-2.5) and nasopharyngeal cancer (NPC). A total of 521,098 men (355 cases and 520,743 non-cases), aged ≥40 years were included in this study. Data were retrieved from the Taiwan Cancer Registry, the Adult Preventive Medical Services Database, and the Air Quality Monitoring Database. PM10-2.5 was significantly associated with a higher risk of NPC after adjusting for SO2, NOx, O3, age, body mass index, smoking, alcohol drinking, betel nut chewing, exercise, hypertension, diabetes, and hyperlipidemia. With PM10-2.5<20.44 μg/m3 as the reference, the ORs and 95% CIs were 1.47; 1.03-2.11, 1.34; 0.94-1.91, and 1.68; 1.16-2.44 for 20.44≤PM10-2.5<24.08, 24.08≤PM10-2.5<29.27, and PM10-2.5≥29.27 μg/m3, respectively. PM10-2.5 remained significantly associated with a higher risk of NPC after further adjustments were made for the aforementioned covariates and PM2.5 The ORs; 95% CIs were 1.42; 0.96 to 2.12, 1.41; 0.94 to 2.10, and 1.71; 1.10 to 2.66 for 20.44≤PM10-2.5<24.08, 24.08≤PM10-2.5<29.27, and PM10-2.5≥29.27 μg/m3, respectively. In conclusion, PM10-2.5 was significantly associated with a higher risk of NPC in Taiwanese men.

Hourly associations between ambient air pollution and emergency ambulance calls in one central Chinese city: Implications for hourly air quality standards

BACKGROUND

Most studies on the short-term health effects of air pollution have been conducted on a daily time scale, while hourly associations remain unclear.

METHODS

We collected the hourly data of emergency ambulance calls (EACs), ambient air pollution, and meteorological variables from 2014 to 2016 in Luoyang, a central Chinese city in Henan Province. We used a generalized additive model to estimate the hourly effects of ambient air pollutants (PM_2.5, PM₁₀, SO₂, and NO₂) on EACs for all natural causes and cardiovascular and respiratory morbidity, with adjustment for potential confounding factors. We further examined the effect modification by temperature, relative humidity, wind speed, and atmospheric pressure using stratified analyses.

RESULTS

In the single-pollutant models, PM_2.5, PM₁₀, SO₂, and NO₂ were associated with an immediate increase in all-cause morbidity at 0, 0, 12, 10 h, separately, after exposure to these pollutants (excess risks: 0.19% (95% confidence interval (CI): 0.03%, 0.35%), 0.13% (95% CI: 0.02%, 0.24%), 0.28% (95% CI: 0.01%, 0.54%) and 0.52% (95% CI: 0.06%, 0.99%), respectively). These effects remained generally stable in two-pollutant models. SO₂ and NO₂ were significantly associated with an immediate increase in risk of cardiovascular morbidity, but the effects on respiratory morbidity were relatively more delayed. The stratified analyses suggested that temperature could modify the association between PM_2.5 and EACs, humidity and atmospheric pressure could modify the association between SO₂ and EACs.

CONCLUSIONS

Our study provides new evidence that higher concentrations of PM_2.5, PM₁₀, SO₂, and NO₂ may have transiently acute effects on all-cause morbidity and subacute effects on respiratory morbidity. SO₂ and NO₂ may also have immediate effects on cardiovascular morbidity. Findings of this study have important implications for the formation of hourly air quality standards.

The impact of air pollutants on ambulance dispatches: A systematic review and meta-analysis of acute effects

A number of systematic reviews have investigated the association between air pollutants and health impacts, these mostly focus on morbidity and mortality from hospital data. Previously, no reviews focused solely on ambulance dispatch data. These data sets have excellent potential for environmental health research. For this review, publications up to April 2019 were identified using three main search categories covering: ambulance services including dispatches; air pollutants; and health outcomes. From 308 studies initially identified, 275 were excluded as they did not relate to ambulance service dispatches, did not report the air pollutant association, and/or did not study ambient air pollution. The main health outcomes in the remaining 33 studies were cardiac arrest (n = 14), cardiovascular (n = 11) and respiratory (n = 10) dispatches. Meta-analyses were performed to summarise pooled relative risk (RR) of pollutants: particulate matter less than 2.5 and 10 μm (PM_2.5, PM₁₀), the fraction between PM₁₀ and PM_2.5 (coarse) and suspended particulate matter (SPM) per 10 μg/m³ increase, carbon monoxide (CO) per 1 ppm increase and of sulphur dioxide (SO₂), nitrogen dioxide (NO₂), and ozone (O₃) per 10 ppb increment and ambulance dispatches. Statistically significant associations were found for ambulance dispatch data for all-respiratory and PM_2.5 at 1.03 (95% CI:1.02-1.04) and at 1.10 (95% CI:1.00-1.21) for asthma and NO₂ associations. For dispatches with subsequent paramedic assessment for cardiac arrest with PM_2.5, CO and coarse dispatches at 1.05 (95% CI:1.03-1.08), 1.10 (95% CI:1.02-1.18) and 1.04 (95% CI:1.01-1.06) respectively. For dispatches with subsequent physician diagnosis for all-respiratory and PM_2.5 at 1.02 (95% CI:1.01-1.03). In conclusion, air pollution was significantly associated with an increase in ambulance dispatch data, including those for cardiac arrest, all-respiratory, and asthma dispatches. Ambulance services should plan accordingly during pollution events. Furthermore, efforts to improve air quality should lead to decreases in ambulance dispatches.

Ambient Particulate Matter and Paramedic Assessments of Acute Diabetic, Cardiovascular, and Respiratory Conditions

Supplemental Digital Content is available in the text.

Background:

Ambulance data provide a useful source of population-based and spatiotemporally resolved information for assessing health impacts of air pollution in nonhospital settings. We used the clinical records of paramedics to quantify associations between particulate matter (PM_2.5) and diabetic, cardiovascular, and respiratory conditions commonly managed by those responding to calls for emergency ambulance services.

Methods:

We evaluated 394,217 paramedic assessments from three states in Southeastern Australia (population 13.2 million) and daily PM_2.5 concentrations modeled at 5 km resolution from 2009 to 2014. We used a time-stratified, case-crossover analysis adjusted for daily meteorology to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for each clinical outcome per 10 µg/m³ increase in daily PM_2.5 at lags from 0 to 2 days.

Results:

Increased PM_2.5 was associated with increased odds of paramedic assessments of hypoglycemia (OR = 1.07; 95% CI = 1.02, 1.12, lag 0), arrhythmia (OR = 1.05; 95% CI = 1.02, 1.09, lag 0), heart failure (OR = 1.07; 95% CI = 1.02, 1.12, lag 1), faint (OR = 1.09; 95% CI = 1.04–1.13, lag 0), asthma (OR = 1.06; 95% CI = 1.01, 1.11, lag 1), chronic obstructive pulmonary disease (OR = 1.07; 95% CI = 1.01, 1.13, lag 1), and croup (OR = 1.09; 95% CI = 1.02, 1.17). We did not identify associations with cerebrovascular outcomes.

Conclusions:

Ambulance data enable the evaluation of important clinical syndromes that are often initially managed in nonhospital settings. Daily PM_2.5 was associated with hypoglycemia, faint, and croup in addition to the respiratory and cardiovascular outcomes that are better established.

Meteorological effects on severe hemoptysis: A hospital-based observational study

BACKGROUND

Although some meteorological factor are likely to contribute to the onset of hemoptysis, few studies have investigated this issue, with none conducted in the Asia-Pacific region. Therefore, the present study aimed to evaluate the associations of meteorological factors with the occurrence of hemoptysis. Differences in the frequency of hemoptysis among several calendar variables were also assessed.

METHODS

A total of 47 hemoptysis patients aged ≥ 20 years undergoing bronchial artery embolization in Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers from January 2012 to December 2017 were included in the study. All hemoptysis events were assembled in a single time series, and the proportion of hemoptysis days was 2.1%. The associations of meteorological variables with hemoptysis days were estimated as odds ratios with 95% confidence intervals by using multivariable-adjusted logistic regression models. The frequency of hemoptysis days was compared among several calendar variables using a chi-square test.

RESULTS

Mean relative humidity was negatively associated with hemoptysis (P for trend = 0.02). The inverse association remained significant when only the hemoptysis events with no infectious lung diseases were used (P for trend=0.02). No significant difference was observed in the occurrence of hemoptysis among seasons, months, or other calendar variables (all P ≥ 0.21).

CONCLUSIONS

Lower relative humidity was a significant risk factor for the development of hemoptysis. Clinicians should be aware of the potential for increases in hemoptysis events on days with low ambient humidity.

Association between gaseous pollutants and emergency ambulance dispatches for asthma in Chengdu, China: a time-stratified case-crossover study

Objectives

The association between concentrations of sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), ozone (O₃), and emergency ambulance dispatches (EADs) for asthma was explored in the central Sichuan Basin of southwestern China for the first time.

Methods

EADs for asthma were collected from the Chengdu First-Aid Command Center. Pollutant concentrations were collected from 24 municipal environmental monitoring centers and including SO₂, NO₂, CO, daily 8-h mean concentrations of O₃ (O₃-8 h), and particulate matter less than 2.5 μm in aerodynamic diameter (PM_2.5). The climatic data were collected from the Chengdu Municipal Meteorological Bureau. All data were collected from years spanning 2013–2017. A time-stratified case-crossover design was used to analyze the data.

Results

After controlling for temperature, relative humidity, and atmospheric pressure, IQR increases in SO₂ (13 μg/m³), NO₂ (17 μg/m³), and CO (498 μg/m³) were associated with 18.8%, 11.5%, and 3.1% increases in EADs for asthma, respectively. The associations were strongest for EADs and SO₂, NO₂, and CO levels with 3-, 5-, and 1-day lags, respectively.

Conclusions

This study provides additional data to the limited body of literature for potential health risks arising from ambient gaseous pollutants. The results of the study suggest that increased concentrations of SO₂, NO₂, and CO were positively associated with emergency ambulance dispatches for asthma in Chengdu, China. Further studies are needed to investigate the effects of individual air pollutants on asthma.

Seasonal and meteorological impacts on primary spontaneous pneumothorax

Background

Although several studies have suggested that primary spontaneous pneumothorax (PSP) might occur in clusters, only a few studies have found seasonal variations in PSP occurrence. Some meteorological parameters might be related to the occurrence of PSP occurrence, however, the effects of weather variations on the onset of PSP are still controversial.

Methods

We examined seasonal differences in the occurrence of PSP and the meteorological risk factors for PSP. All PSP patients aged <40 years who were admitted to Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers from April 2007 through March 2013 were included in the study.

Results

The incidence rates of PSP were 16.7 and 2.1 per 100,000 person-years in men and women, respectively. The frequency of PSP days among months and seasons was significantly different with a peak in September and autumn. Daily changes in maximum wind speed had positive associations with PSP days [crude OR =1.11 (95% CI: 1.02-1.21) per 1 m/s, P=0.02; multivariable-adjusted OR =1.11 (95% CI: 1.00-1.23) per 1 m/s, P=0.05].

Conclusions

PSP tends to cluster seasonally. Increased wind speed may play a role in the development of PSP.

The relationship between airborne fine particle matter and emergency ambulance dispatches in a southwestern city in Chengdu, China

High levels of fine particulate matter (PM_2.5) are known to cause adverse effects to human health. The goal of this study was to estimate the acute health effects of short-term exposure to ambient PM_2.5 by analyzing cause-specific emergency ambulance dispatches as the endpoint in Chengdu, a city in Sichuan Province in southwest China. The ambient PM_2.5 concentration of Chengdu reached 63 μg/m³ in 2015. Data related to the causes of specific emergency ambulance dispatches, air pollution, and meteorological conditions were collected from 2013 to 2015 (1095 days). A generalized additive model (GAM) was constructed to control the confounding conditions and to estimate the effects of PM_2.5 on human health conditions. Emergency ambulance dispatches for all causes with (RR for lag0 = 1.0010, 95%CI: 1.0002, 1.0019) or without injuries (RR for lag0 = 1.0012, 95%CI: 1.0002, 1.0022), respiratory diseases (RR for lag0 = 1.0051, 95%CI: 1.0012, 1.0089), and cardiovascular diseases (RR for lag0 = 1.0041, 95%CI: 1.0009, 1.0074) were associated with ambient PM_2.5 concentrations in Chengdu. In addition, the effects of PM_2.5 were not confounded by ozone.

Effects of noise on telephone calls to the Madrid Regional Medical Emergency Service (SUMMA 112)

BACKGROUND

Although the effects of noise on population morbidity and mortality have been observed both in the short and long term, the morbidity and mortality indicators used to date have not enabled information on such health effects to be accessed in real time. At an international level, there are relatively few studies, mostly recent, which have considered an alternative indicator, such as the demand for medical attention provided by emergency services, taking into account environmental factors other than noise.

OBJECTIVES

To ascertain the short-term effect of road-traffic noise levels on medical care, broken down by organic, circulatory and respiratory causes, provided by the Madrid Regional Medical Emergency Service (Servicio de Urgencia Médica de Madrid/SUMMA 112).

METHODS

We used an ecological time-series study and fitted Poisson regression models, to analyse the number of daily, cause-specific episodes of care provided in situ by SUMMA 112, via emergency ambulance dispatches, across the period 01/01/2008-31/12/2009. To this end, we considered diurnal (Leqd: 7-23h), nocturnal (Leqn: 23-7h) and daily (Leq24: 24h) noise (in db(A)) as the principal factor, and chemical air pollution (µg/m³) and temperature (°C) as the control variables. We also controlled for trend and seasonalities, the autoregressive nature of the series, and day of the week.

RESULTS

Nocturnal noise exceeded the WHO threshold (55 db(A)) on 100% of nights, despite displaying a downward trend across the study period. For all causes, with the exception of emergency calls due to ischaemic disease, it was nocturnal rather than diurnal noise levels that had a short-term effect (lags 0-1) on SUMMA 112 calls, with this impact being greater for respiratory than for circulatory causes. Hence, for every increase of 1db in Leqn, the relative risks (RRs) were as follows: 1.11 (95% CI 1.09-1.13) for organic causes; 1.14 (95% CI: 1.11-1.18) for respiratory causes; and 1.08 (95% CI: 1.05-1.10) for circulatory causes.

CONCLUSION

SUMMA 112 data give access to real-time information on the health effects associated with increases in noise levels, which cannot be obtained via mortality or hospital-admission data, since these are collected in the longer term. Accordingly, this is something that would be immediately applicable in any future implementation of a syndromic surveillance system focusing on the effects of environmental pollutants on health.

Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan

Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7μg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10μg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in <3weeks hospitalization or no hospitalization) when compared to severe medical conditions (e.g. critical cases, and cases that led to >3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being.