Two-way effect modifications of air pollution and air temperature on total natural and cardiovascular mortality in eight European urban areas

City-level impact of extreme temperatures and mortality in Latin America

Climate change and urbanization are rapidly increasing human exposure to extreme ambient temperatures, yet few studies have examined temperature and mortality in Latin America. We conducted a nonlinear, distributed-lag, longitudinal analysis of daily ambient temperatures and mortality among 326 Latin American cities between 2002 and 2015. We observed 15,431,532 deaths among ≈2.9 billion person-years of risk. The excess death fraction of total deaths was 0.67% (95% confidence interval (CI) 0.58-0.74%) for heat-related deaths and 5.09% (95% CI 4.64-5.47%) for cold-related deaths. The relative risk of death was 1.057 (95% CI 1.046-1.067%) per 1 °C higher temperature during extreme heat and 1.034 (95% CI 1.028-1.040%) per 1 °C lower temperature during extreme cold. In Latin American cities, a substantial proportion of deaths is attributable to nonoptimal ambient temperatures. Marginal increases in observed hot temperatures are associated with steep increases in mortality risk. These risks were strongest among older adults and for cardiovascular and respiratory deaths.

Contribution of heavy metals in PM2.5 to cardiovascular disease mortality risk, a case study in Guangzhou, China

Heavy metals play an important role in inducing fine particulate matter (PM_2.5) related cardiovascular disease (CVD). However, most of the past researches concerned the associations between CVD mortality and the PM_2.5 mass, which may not reveal the CVD mortality risk contributed by heavy metals in PM_2.5. This study explored the correlations between individual heavy metals in PM_2.5 and CVD mortality, identified the heavy metals that significantly contribute to PM_2.5-related CVD, heart disease (HD), and cerebrovascular disease (CEV) mortality, and attempted to establish corresponding source control measures. Over a 2-year study period, PM_2.5 was sampled daily in Guangzhou, China and analyzed for heavy metals. The airborne pollution and weather data, along with CVD, HD, and CEV mortality, were obtained at the same time. The excess risk (ER) of mortality was linked to the individual heavy metals using a distributed lag non-linear model. PM_2.5 and most heavy metals showed significant correlations with the CVD, HD, and CEV mortality; the largest cumulative ER (LCER) values of CVD mortality associated with an interquartile range increase in the levels of lead, cadmium, arsenic, selenium, antimony, nickel, thallium, aluminum, iron, and PM_2.5 were 2.43%, 2.23%, 1.66%, 2.39%, 1.19%, 1.21%, 2.69%, 3.29%, 1.74%, and 2.40%, respectively. Most heavy metals showed comparable LCER values of HD and CEV mortality. Heavy metals with the addition of PM_2.5 were divided into three groups following their LCER values; lead, cadmium, arsenic, antimony, thallium, zinc, aluminum, and iron, whose contributions were greater than or equal to the average effect of the PM_2.5 components, should be limited on a priority basis. These findings indicated that heavy metals play roles in the CVD, HD, and CEV mortality risk of PM_2.5, and specific control measures which aimed at the emission sources should be taken to reduce the CVD mortality risk of PM_2.5.

Cause-specific cardiovascular disease mortality attributable to ambient temperature: A time-stratified case-crossover study in Jiangsu province, China

BACKGROUND

Exposure to non-optimum ambient temperature has been linked to increased risk of total cardiovascular disease (CVD) mortality; however, the adverse effects on mortality from specific types of CVD remain less understood.

OBJECTIVES

To comprehensively investigate the association of ambient temperature with cause-specific CVD mortality, and to estimate and compare the corresponding mortality burden.

METHODS

We conducted a time-stratified case-crossover study of 1000,014 CVD deaths in Jiangsu province, China during 2015-2019 using data from the China National Mortality Surveillance System. Residential daily 24-hour average temperature for each subject was extracted from a validated grid data at a spatial resolution of 0.0625° × 0.0625°. We fitted distributed lag non-linear models (DLNM) based on conditional logistic regression to quantitatively investigate the association of ambient temperature with total and cause-specific CVD mortality, which was used to further estimate mortality burden attributable to non-optimum ambient temperatures.

RESULTS

With adjustment for relative humidity, we observed reverse J-shaped exposure-response associations of ambient temperature with total and cause-specific CVD mortality, with minimum mortality temperatures ranging from 19.5 °C to 23.0 °C. An estimated 20.3% of the total CVD deaths were attributable to non-optimum temperatures, while the attributable fraction (AF) of mortality from chronic rheumatic heart diseases, hypertensive diseases, ischemic heart diseases (IHD), pulmonary heart disease, stroke, and sequelae of stroke was 22.4%, 23.2%, 23.3%, 20.9%, 17.6% and 21.3%, respectively. For total and cause-specific CVDs, most deaths were attributable to moderate cold temperature. We observed significantly higher mortality burden from total and certain cause-specific CVDs in adults 80 years or older and those who were widowed.

CONCLUSION

Exposure to ambient temperature was significantly associated with increased risk of cause-specific CVD mortality. The burden of CVD mortality attributable to non-optimum temperature was substantial especially in older and widowed adults, and significantly varied across specific types of CVD.

Seasonal characteristics of temperature variability impacts on childhood asthma hospitalization in Hefei, China: Does PM2.5 modify the association?

OBJECTIVES

Evidence of childhood asthma hospitalizations associated with temperature variability (TV) and the attributable risk are limited in China. We aim to use a comprehensive index that reflected both intra- and inter-day TV to assess the TV-childhood asthma relationship and disease burden, further to identify seasonality vulnerable populations, and to explore the effect modification of PM_2.5.

METHODS

A quasi-distributed lagged nonlinear model (DLNM) combined with a linear threshold function was applied to estimate the association between TV and childhood asthma hospitalizations during 2013-2016 in Hefei, China. Subgroup analysis was conducted by age and sex. Disease burden is reflected by the attributable fraction and attributable number. Besides, modifications of PM_2.5 were tested by introducing the cross-basis of TV and binary PM_2.5 as an interaction term.

RESULTS

The risk estimates peaked at TV_0-3 and TV_0-4 in the cool and the warm season separately, with RR of 1.051 (95%CI: 1.021-1.081) and 1.072 (95%CI: 1.008-1.125), and the effects lasted longer in the cool season. The school-age children in the warm season and all subgroups except pre-school children in the cool season were vulnerable to TV. It is estimated that the disease burden related to TV account for 6.2% (95% CI: 2.7%-9.4%) and 4% (95% CI: 0.6%-7.1%) during the cool and warm seasons in TV_0-3. In addition, the risks of TV were higher under the high PM_2.5 level compared with the low PM_2.5 level in the cool season, although no significant differences between them.

CONCLUSIONS

TV exposure significantly increases the risk and disease burden of childhood asthma hospitalizations, especially in the cool season. More medical resources should be allocated to school-age children. Giving priority to pay attention to TV in the cool season in practice could obtain the greatest public health benefits and those days with high TV and high PM_2.5 need more attention.

Association of population migration with air quality: Role of city attributes in China during COVID-19 pandemic (2019-2021)

Atmospheric pollution studies have linked diminished human activity during the COVID-19 pandemic to improve air quality. This study was conducted during January to March (2019-2021) in 332 cities in China to examine the association between population migration and air quality, and examined the role of three city attributes (pollution level, city scale, and lockdown status) in this effect. This study assessed six air pollutants, namely CO, NO₂, O₃, PM₁₀, PM_2.5, and SO₂, and measured meteorological data, with-in city migration (WCM) index, and inter-city migration (ICM) index. A linear mixed-effects model with an autoregressive distributed lag model was fitted to estimate the effect of the percent change in migration on air pollution, adjusting for potential confounding factors. In summary, lower migration was associated with decreased air pollution (other than O₃). Pollution change in susceptibility is more likely to occur in NO₂ decrease and O₃ increase, but unsusceptibility is more likely to occur in CO and SO₂, to city attributes from low migration. Cities that are less air polluted and population-dense may benefit more from decreasing PM₁₀ and PM_2.5. The associations between population migration and air pollution were stronger in cities with stringent traffic restrictions than in cities with no lockdowns. Based on city attributes, an insignificant difference was observed between the effects of ICM and WCM on air pollution. Findings from this study may gain knowledge about the potential interaction between migration and city attributes, which may help decision-makers adopt air-quality policies with city-specific targets and paths to pursue similar air quality improvements for public health but at a much lower economic cost than lockdowns.

Interactive effects of cold spell and air pollution on outpatient visits for anxiety in three subtropical Chinese cities

BACKGROUND

Although low temperature and air pollution exposures have been associated with the risk of anxiety, their combined effects remain unclear.

OBJECTIVE

To investigate the independent and interactive effects of low temperature and air pollution exposures on anxiety.

METHOD

Using a case-crossover study design, the authors collected data from 101,636 outpatient visits due to anxiety in three subtropical Chinese cities during the cold season (November to April in 2013 through 2018), and then built conditional logistic regression models based on individual exposure assessments [temperature, relative humidity, particulate matter (PM_2.5, PM₁₀), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂)] and twelve cold spell definitions. Additive-scale interactions were assessed using the relative excess risk due to interaction (RERI).

RESULTS

Both cold spell and air pollution were significantly associated with outpatients for anxiety. The effects of cold spell increased with its intensity, ranging from 8.98% (95% CI: 2.02%, 16.41%) to 15.24% (95% CI: 6.75%, 24.39%) in Huizhou. Additionally, each 10 μg/m³ increase of PM_2.5, PM₁₀, NO₂ and SO₂ was associated with a 1.51% (95% CI: 0.61%, 2.43%), 1.58% (95% CI: 0.89%, 2.28%), 13.95% (9.98%, 18.05%) and 11.84% (95% CI: 8.25%, 15.55%) increase in outpatient visits for anxiety. Synergistic interactions (RERI >0) of cold spell with all four air pollutants on anxiety were observed, especially for more intense cold spells. For particulate matters, these interactions were found even under mild cold spell definitions [RERI: 0.11 (95% CI: 0.02, 0.21) for PM_2.5, and 0.24 (95% CI: 0.14, 0.33) for PM₁₀]. Stratified analyses yielded a pronounced results in people aged 18-65 years.

CONCLUSIONS

These findings indicate that both cold spell and air pollution are important drivers of the occurrence of anxiety, and simultaneous exposure to these two factors might have synergistic effects on anxiety. These findings highlight the importance of controlling air pollution and improving cold-warning systems.

Climatic influences on cardiovascular diseases

Classical risk factors only partially account for variations in cardiovascular disease incidence; therefore, also other so far unknown features, among which meteorological factors, may influence heart diseases (mainly coronary heart diseases, but also heart failure, arrhythmias, aortic dissection and stroke) rates. The most studied phenomenon is ambient temperature. The relation between mortality, as well as cardiovascular diseases incidence, and temperature appears graphically as a ‘‘U’’ shape. Exposure to cold, heat and heat waves is associated with an increased risk of acute coronary syndromes. Other climatic variables, such as humidity, atmospheric pressure, sunlight hours, wind strength and direction and rain/snow precipitations have been hypothesized as related to fatal and non-fatal cardiovascular diseases incidence. Main limitation of these studies is the unavailability of data on individual exposure to weather parameters. Effects of weather may vary depending on other factors, such as population disease profile and age structure. Climatic stress may increase direct and indirect risks to human health via different, complex pathophysiological pathways and exogenous and endogenous mechanisms. These data have attracted growing interest because of the recent earth’s climate change, with consequent increasing ambient temperatures and climatic fluctuations. This review evaluates the evidence base for cardiac health consequences of climate conditions, and it also explores potential further implications.

Combined effects of air pollution and extreme heat events among ESKD patients within the Northeastern United States

BACKGROUND

Increasing number of studies have linked air pollution exposure with renal function decline and disease. However, there is a lack of data on its impact among end-stage kidney disease (ESKD) patients and its potential modifying effect from extreme heat events (EHE).

METHODS

Fresenius Kidney Care records from 28 selected northeastern US counties were used to pool daily all-cause mortality (ACM) and all-cause hospital admissions (ACHA) counts. County-level daily ambient PM_2.5 and ozone (O₃) were estimated using a high-resolution spatiotemporal coupled climate-air quality model and matched to ESKD patients based on ZIP codes of treatment sites. We used time-stratified case-crossover analyses to characterize acute exposures using individual and cumulative lag exposures for up to 3 days (Lag 0-3) by using a distributed lag nonlinear model framework. We used a nested model comparison hypothesis test to evaluate for interaction effects between air pollutants and EHE and stratification analyses to estimate effect measures modified by EHE days.

RESULTS

From 2001 to 2016, the sample population consisted of 43,338 ESKD patients. We recorded 5217 deaths and 78,433 hospital admissions. A 10-unit increase in PM_2.5 concentration was associated with a 5% increase in ACM (rate ratio [RR_Lag0-3]: 1.05, 95% CI: 1.00-1.10) and same-day O₃ (RR_Lag0: 1.02, 95% CI: 1.01-1.03) after adjusting for extreme heat exposures. Mortality models suggest evidence of interaction and effect measure modification, though not always simultaneously. ACM risk increased up to 8% when daily ozone concentrations exceeded National Ambient Air Quality Standards established by the United States, but the increases in risk were considerably higher during EHE days across lag periods.

CONCLUSION

Our findings suggest interdependent effects of EHE and air pollution among ESKD patients for all-cause mortality risks. National level assessments are needed to consider the ESKD population as a sensitive population and inform treatment protocols during extreme heat and degraded pollution episodes.

Association between air pollution and emergency room visits for eye diseases and effect modification by temperature in Beijing, China

The growing burden of eye disease worldwide has aroused increasing concern upon its environmental etiology. This study aims to evaluate the associations of air pollutants with emergency room visits for eye diseases and the effect modification by temperature. Based on 24,389 cases from a general hospital during 2014-2019 in Beijing, China, this study used generalized additive models to examine the associations of air pollutants and emergency room visits for total eye diseases (ICD10: H00-H59) and conjunctivitis (ICD10: H10). Short-term exposures to PM2.5, PM10, CO, and NO2 were associated with increased visits for total eye diseases and conjunctivitis, and stronger effect estimates were observed in high (>75th) temperature group for PM2.5, PM10, CO, and NO2 and low (<75th) temperature group for CO and NO2. For instance, a 10 μg/m3 increase in PM2.5 at lag0-1 were associated with a 0.73% (95% CI: 0.23%, 1.24%) increase in total eye disease visits and a 1.34% (95% CI: 0.55%, 2.13%) increase in conjunctivitis visits, respectively. Meanwhile, a 10 μg/m3 increase in PM2.5 was associated with a 1.57% (95% CI: 0.49%, 2.64%) change in high temperature group and a 0.48% (95% CI: -0.24%, 1.19%) change in medium temperature group (P for interaction = 0.04) in total eye disease visits. Our study emphasizes the importance of controlling the potential hazards of air pollutants on eyes, especially on days with relatively higher or colder temperature.

Modeling complex effects of exposure to particulate matter and extreme heat during pregnancy on congenital heart defects: A U.S. population-based case-control study in the National Birth Defects Prevention Study

BACKGROUND/OBJECTIVE

Research suggests gestational exposure to particulate matter ≤2.5 μm (PM2.5) and extreme heat may independently increase risk of birth defects. We investigated whether duration of gestational extreme heat exposure modifies associations between PM2.5 exposure and specific congenital heart defects (CHDs). We also explored nonlinear exposure-outcome relationships.

METHODS

We identified CHD case children (n = 2824) and non-malformed live-birth control children (n = 4033) from pregnancies ending between 1999 and 2007 in the National Birth Defects Prevention Study, a U.S. population-based multicenter case-control study. We assigned mothers 6-week averages of PM2.5 exposure during the cardiac critical period (postconceptional weeks 3-8) using the closest monitor within 50 km of maternal residence. We assigned a count of extreme heat days (EHDs, days above the 90th percentile of daily maximum temperature for year, season, and weather station) during this period using the closest weather station. Using generalized additive models, we explored logit-nonlinear exposure-outcome relationships, concluding logistic models were reasonable. We estimated joint effects of PM2.5 and EHDs on six CHDs using logistic regression models adjusted for mean dewpoint and maternal age, education, and race/ethnicity. We assessed multiplicative and additive effect modification.

RESULTS

Conditional on the highest observed EHD count (15) and at least one critical period day during spring/summer, each 5 μg/m3 increase in average PM2.5 exposure was significantly associated with perimembranous ventricular septal defects (VSDpm; OR: 1.54 [95% CI: 1.01, 2.41]). High EHD counts (8+) in the same population were positively, but non-significantly, associated with both overall septal defects and VSDpm. Null or inverse associations were observed for lower EHD counts. Multiplicative and additive effect modification estimates were consistently positive in all septal models.

CONCLUSIONS

Results provide limited evidence that duration of extreme heat exposure modifies the PM2.5-septal defects relationship. Future research with enhanced exposure assessment and modeling techniques could clarify these relationships.

Effects of prenatal exposures to air sulfur dioxide/nitrogen dioxide on toddler neurodevelopment and effect modification by ambient temperature

Emerging evidence suggests that prenatal exposure to ambient SO2 or NO2 induces fetal brain-damage. However, effects of prenatal exposure to SO2 or NO2 on toddler neurodevelopment and the effect-modification by ambient temperature remain unclear. Therefore, a prospective birth-cohort study was conducted from 2010 to 2012 in Shanghai, and 225 mother-child pairs were followed-up from mid-to-late pregnancy until 24-36 months postpartum. During the whole pregnancy, daily SO2/NO2 and temperature levels were obtained for each woman. Gesell-Development-Schedule was used to assess toddler neurodevelopment in the domains of gross-motor, fine-motor, adaptive-behavior, language and social-behavior. Distributed-lag-nonlinear-models simultaneously accounting for exposure-response and lag-response associations were applied to assess the impacts of prenatal SO2/NO2 exposure on neurodevelopment. Each 10-μg/m3 increase in weekly average SO2 concentrations had adverse associations with gross-motor in gestational-weeks 1-6, with adaptive-behavior in weeks 26-30, and with language in weeks 30-36 (developmental-quotient changes: - 1.17% to - 0.12%, P-values < 0.05). Each 10-μg/m3 increase in weekly average NO2 concentrations had adverse associations with gross-motor in gestational-weeks 33-36, with fine-motor in weeks 26-36 and with social-behavior in weeks 31-36 (developmental-quotient changes: - 0.91% to - 0.20%, P-values < 0.05). The cumulative effects for the whole pregnancy showed that each 10-μg/m3 increase in SO2 induced significant deficits in gross-motor and adaptive-behavior (developmental-quotient changes: - 4.71% and - 4.06%, respectively, P < 0.05). We found prenatal cumulative SO2 exposure induced more deficits in low temperature in language and adaptive-behavior than in high/moderate temperature. Thus, prenatal ambient SO2/NO2 exposure in specific time-windows (1st and 3rd trimesters for SO2; 3rd trimester for NO2) could impair toddler neurodevelopment and low temperature may aggravate the SO2-induced neurotoxicity.

Acute effects of ambient nitrogen oxides and interactions with temperature on cardiovascular mortality in Shenzhen, China

BACKGROUND

Though inconsistent, acute effects of ambient nitrogen oxides on cardiovascular mortality have been reported. Whereas, interactive roles of temperature on their relationships and joint effects of different indicators of nitrogen oxides were less studied. This study aimed to extrapolate the independent roles of ambient nitrogen oxides and temperature interactions on cardiovascular mortality.

METHODS

Data on mortality, air pollutants, and meteorological factors in Shenzhen from 2013 to 2019 were collected. Three indicators including nitric oxide (NO), nitrogen dioxide (NO₂), and nitrogen oxides (NO_X) were studied. Adjusted generalized additive models (GAMs) were applied to analyse their associations with cardiovascular mortality in different groups.

RESULTS

The average daily concentrations of NO, NO₂, and NO_X were 11.7 μg/m³, 30.7 μg/m³, and 53.2 μg/m³, respectively. Significant associations were shown with each indicator. Cumulative effects of nitrogen oxides were more obvious than distributed lag effects. Males, population under 65 years old, and population with stroke-related condition were more susceptible to nitrogen oxides. Adverse effects of nitrogen oxides were more significant at low temperature. Impacts of NO₂ on cardiovascular mortality, and NO on stroke mortality were the most robust in the multi-pollutant models, whereas variations were shown in the other relationships.

CONCLUSIONS

Low levels of nitrogen oxides showed acute and adverse impacts and the interactive roles of temperature on cardiovascular mortality. Cumulative effects were most significant and joint effects of nitrogen oxides required more attention. Population under 65 years old and population with stroke-related health condition were susceptible, especially days at lower temperature.

The impact of extreme temperatures on human mortality in the most populated cities of Romania

The impact of extreme weather conditions on humans is one of the most important topics in biometeorology studies. The main objective of this study is to analyze the relationship between temperature-related weather conditions and natural mortality in the five most populated cities of Romania, namely, Bucharest, Cluj-Napoca, Constanța, Iași, and Timișoara. The results of this study aim to bridge a gap in national research. In the present paper, we used daily natural mortality data and daily minimum and maximum air temperatures. The distributed lag nonlinear model (DLNM) allowed us to identify weather conditions associated with natural mortality. The most important results are as follows: (i) a higher daily mortality is related to a high frequency of heat stress conditions; (ii) a higher maximum temperature increases the relative risk (RR) of natural mortality; (iii) the maximum number of fatalities is recorded on the first day of high-temperature events; and (iv) individuals much more easily adapt to cold stress conditions. The main conclusion in this study is that the inhabitants of the most populated cities in Romania are more sensitive to high-temperature stress than to low-temperature stress.

[Climate crisis and its impact on human health]

The climate crisis and its consequences represent the greatest challenge facing human health and health care system in the 21st century. It threatens to undermine the last decades of health gains. Rising temperatures, fires, floods and droughts can directly and indirectly cause human pathologies, that are physical and mental. Extreme weather events lead to loss of life, basic life resources and cause severe mental burden. More intense and frequent heat waves due to global warming impact human health and increase mortality, especially for those most vulnerable. The heat-related health risk depends on individual state of health as well as environmental and socioeconomic characteristics of residential areas. Increasing exposure to air pollutants, due to wildfires and anthropogenic emissions, raises respiratory and cardiovascular mortality. Climate warming changes ecosystems and enhances biological invasions that can better adapt to warm environments. Pathogen profiles are changing, transmission and spread of vector-borne diseases as Malaria or Dengue are increasing. Further, rising temperatures and air pollution increase the production and allergenicity of pollen, associated with higher prevalence of allergic diseases. Protective environmental factors, as biodiversity or diverse microbiome, should be given greater consideration in future research.Health sector has the central responsibility as the fifth-largest greenhouse gas emitter to transform in a climate-neutral and sustainable way, e. g. by efficient use of resources. Further education and training in this area should be intensified and included in curricula for medical staff. Furthermore, medical professionals must educate patients about the burden of climate change, climate resilience, and the benefits of CO2 reduction - for human but also for planetary health.

Personal exposure to particulate matter and heart rate variability among informal electronic waste workers at Agbogbloshie: a longitudinal study

BACKGROUND

Informal electronic waste recycling activities are major contributors to ambient air pollution, yet studies assessing the effects or relationship between direct/continuous exposure of informal e-waste workers to particulate matter and cardiovascular function are rare.

METHODS

Repeated measurements of fractions of PM_2.5, PM_10-2.5, and PM₁₀ in personal air of informal e-waste workers, (n = 142) and a comparable group (n = 65) were taken over a period of 20 months (March 2017 to November, 2018). Concurrently, 5-min resting electrocardiogram was performed on each participant to assess resting heart rate variability indices. Linear mixed-effects models were used to assess the association between PM fractions and cardiac function.

RESULTS

SDNN, RMSSD, LF, HF and LH/HF ratio were all associated with PM. Significant associations were observed for PM_2.5 and Mean NN (p = 0.039), PM10 and SDNN (p = 0.035) and PM 10-2.5 and LH/HF (p = 0.039). A 10 μg/m³ increase in the concentrations of PM _2.5, PM_10-2.5, and PM₁₀ in personal air was associated with reduced HRV indices and increased resting HR. A 10 μg/m³ per interquartile (IQR) increase in PM_10-2.5 and PM₁₀, decreased SDNN by 11% [(95% CI: - 0.002- 0.000); (p = 0.187)] and 34% [(95% CI: - 0.002-0.001); (p = 0.035)] respectively. However, PM_2.5 increased SDNN by 34% (95% CI: - 1.32-0.64); (p = 0.493). Also, 10 μg/m³ increase in PM_2.5, PM_10-2.5 and PM₁₀ decreased RMSSD by 27% [(- 1.34-0.79); (p = 0.620)], 11% [(- 1.73, 0.95); (p = 0.846)] and 0.57% [(- 1.56-0.46); (p = 0.255%)].

CONCLUSION

Informal e-waste workers are at increased risk of developing cardiovascular disease from cardiac autonomic dysfunction as seen in reduced HRV and increased heart rate.

Temperature-Modified Acute Effects of Ozone on Human Mortality - Beijing Municipality, Tianjin Municipality, Hebei Province, and Surrounding Areas, China, 2013-2018

What is already known about this topic?

Ozone (O₃) is a weather-driven photochemical ambient pollutant, and its harm to human health may be affected by meteorological factors such as temperature. However, there is conflicting evidence regarding whether temperature can modify the effects of ozone on health.

What is added by this report?

Short-term exposure to O₃ in the Beijing Municipality, Tianjin Municipality, Hebei Province, and surrounding areas was associated with an increased risk of human mortality and that association was positive modified by relatively higher (>75th 24 h-average temperature) or extreme cold temperature (<10th 24 h-average temperature). Under extreme temperatures (>90th 24 h-average temperature) modification, the associations were further increased. Cardiopulmonary diseases, as vulnerable diseases of air pollution, their mortality risks associated with O₃ were markedly strengthened by uncomfortable temperatures.

What are the implications for public health practice?

This study suggests that policymakers should pay attention to the synergistic effect between ozone and heat or extreme cold on human health, as well as provide evidence for establishing an integrated early-warning system to protect the public against both uncomfortable temperature and air pollution.

Heterogeneity and threshold effects of environmental regulation on health expenditure: Considering the mediating role of environmental pollution

A comprehensive understanding of the heterogeneity and threshold effects of environmental regulation on health expenditure is essential for policy design and decision-making. This case study seeks to analyze the heterogeneity and threshold effects using panel data, which covers 30 Chinese provinces from 2007 to 2017. We examine the linear and nonlinear impacts of environmental regulation on health expenditure by using the Bayesian quantile regression and panel threshold regression, respectively. The empirical research results indicate a significant heterogeneous effect of environmental regulation on health expenditure in provinces where health expenditure falls in different quintiles. It shows mainly two effects: a positive effect of environmental regulation on health expenditure in provinces in the low quintiles and high quintiles of health expenditure; and a negative interrelationship between environmental regulation and health expenditure for provinces in the medium quintiles of health expenditure. A single threshold effect of environmental regulation on health expenditure is found to be different among three regions: the eastern, central and western regions. Specifically, in eastern and western China, the environmental regulations are stricter, and this helps reduce the health expenditures relating to environmental pollution. However, it was found that stricter environmental regulations do not reduce health expenditures in central China.

Air pollution and cardiovascular disease hospitalization - Are associations modified by greenness, temperature and humidity?

BACKGROUND

Studies have observed associations between long-term air pollution and cardiovascular disease hospitalization. Little is known, however, about effect modification of these associations by greenness, temperature and humidity.

METHODS

We constructed an open cohort consisting of all fee-for-service Medicare beneficiaries, aged ≥ 65, living in the contiguous US from 2000 through 2016 (~63 million individuals). We assigned annual average PM2.5, NO2 and ozone zip code concentrations. Cox-equivalent Poisson models were used to estimate associations with first cardiovascular disease (CVD), coronary heart disease (CHD) and cerebrovascular disease (CBV) hospitalization.

RESULTS

PM2.5 and NO2 were both positively associated with CVD, CHD and CBV hospitalization, after adjustment for potential confounders. Associations were substantially stronger at the lower end of the exposure distributions. For CVD hospitalization, the hazard ratio (HR) of PM2.5 was 1.041 (1.038, 1.045) per IQR increase (4.0 µg/m3) in the full study population and 1.327 (1.305, 1.350) per IQR increase for a subgroup with annual exposures always below 10 µg/m3 PM2.5. Ozone was only positively associated with CVD, CHD and CBV hospitalization for the low-exposure subgroup (<40 ppb). Associations of PM2.5 were stronger in areas with higher greenness, lower ozone and Ox, lower summer and winter temperature and lower summer and winter specific humidity.

CONCLUSION

PM2.5 and NO2 were positively associated with CVD, CHD and CBV hospitalization. Associations were more pronounced at low exposure levels. Associations of PM2.5 were stronger with higher greenness, lower ozone and Ox, lower temperature and lower specific humidity.

Urban heat: an increasing threat to global health

Shilu Tong and colleagues describe the health consequences of extreme urban heat and the priorities for action and research to mitigate the harms

Fuel feedstock determines biodiesel exhaust toxicity in a human airway epithelial cell exposure model

BACKGROUND

Biodiesel is promoted as a sustainable replacement for commercial diesel. Biodiesel fuel and exhaust properties change depending on the base feedstock oil/fat used during creation. The aims of this study were, for the first time, to compare the exhaust exposure health impacts of a wide range of biodiesels made from different feedstocks and relate these effects with the corresponding exhaust characteristics.

METHOD

Primary airway epithelial cells were exposed to diluted exhaust from an engine running on conventional diesel and biodiesel made from Soy, Canola, Waste Cooking Oil, Tallow, Palm and Cottonseed. Exhaust properties and cellular viability and mediator release were analysed post exposure.

RESULTS

The exhaust physico-chemistry of Tallow biodiesel was the most different to diesel as well as the most toxic, with exposure resulting in significantly decreased cellular viability (95.8 ± 6.5%) and increased release of several immune mediators including IL-6 (+223.11 ± 368.83 pg/mL) and IL-8 (+1516.17 ± 2908.79 pg/mL) above Air controls. In contrast Canola biodiesel was the least toxic with exposure only increasing TNF-α (4.91 ± 8.61).

CONCLUSION

This study, which investigated the toxic effects for the largest range of biodiesels, shows that exposure to different exhausts results in a spectrum of toxic effects in vitro when combusted under identical conditions.

Effect of extreme temperatures on daily emergency room visits for mental disorders

Relatively few studies investigated the effects of extreme temperatures (both heat and cold) on mental health (ICD-9: 290-319; ICD-10: F00-F99) and the potential effect modifications by individuals' age, sex, and race. We aimed to explore the effect of extreme temperatures of both heat and cold on the emergency room (ER) visits for mental health disorders, and conducted a stratified analysis to identify possible susceptible population in Erie and Niagara counties, NY, USA. To assess the short-term impacts of daily maximum temperature on ER visits related to mental disorders (2009-2015), we applied a quasi-Poisson generalized linear model combined with a distributed lag non-linear model (DLNM). The model was adjusted for day of the week, precipitation, long-term time trend, and seasonality. We found that there were positive associations between short-term exposure to extreme ambient temperatures and increased ER visits for mental disorders, and the effects can vary by individual factors. We found heat effect (relative risk (RR) = 1.16; 95% confidence intervals (CI), 1.06-1.27) on exacerbated mental disorders became intense in the study region and subgroup of population (the elderly) being more susceptible to extreme heat than any other age group. For extreme cold, we found that there is a substantial delay effect of 14 days (RR = 1.25; 95% CI = 1.08-1.45), which is particularly burdensome to the age group of 50-64 years old and African-Americans. Our findings suggest that there is a positive association between short-term exposure to extreme ambient temperature (heat and cold) and increased ER visits for mental disorders, and the effects vary as a function of individual factors, such as age and race.

Suicide and Associations with Air Pollution and Ambient Temperature: A Systematic Review and Meta-Analysis

Given health threats of climate change, a comprehensive review of the impacts of ambient temperature and ar pollution on suicide is needed. We performed systematic literature review and meta-analysis of suicide risks associated with short-term exposure to ambient temperature and air pollution. Pubmed, Scopus, and Web of Science were searched for English-language publications using relevant keywords. Observational studies assessing risks of daily suicide and suicide attempts associated with temperature, particulate matter with aerodynamic diameter ≤10 μm (PM₁₀) and ≤2.5 mm (PM_2.5), ozone (O₃), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO) were included. Data extraction was independently performed in duplicate. Random-effect meta-analysis was applied to pool risk ratios (RRs) for increases in daily suicide per interquartile range (IQR) increase in exposure. Meta-regression analysis was applied to examine effect modification by income level based on gross national income (GNI) per capita, national suicide rates, and average level of exposure factors. In total 2274 articles were screened, with 18 studies meeting inclusion criteria for air pollution and 32 studies for temperature. RRs of suicide per 7.1 °C temperature was 1.09 (95% CI: 1.06, 1.13). RRs of suicide per IQR increase in PM_2.5, PM₁₀, and NO₂ were 1.02 (95% CI: 1.00, 1.05), 1.01 (95% CI: 1.00, 1.03), and 1.03 (95% CI: 1.00, 1.07). O₃, SO₂, and CO were not associated with suicide. RR of suicide was significantly higher in higher-income than lower-income countries (1.09, 95% CI: 1.07, 1.11 and 1.20, 95% CI: 1.14, 1.26 per 7.1 °C increased temperature, respectively). Suicide risks associated with air pollution did not significantly differ by income level, national suicide rates, or average exposure levels. Research gaps were found for interactions between air pollution and temperature on suicide risks.

Association between ambient temperature and childhood respiratory hospital visits in Beijing, China: a time-series study (2013-2017)

Little is known on the potential impact of temperature on respiratory morbidity, especially for children whose respiratory system can be more vulnerable to climate changes. In this time-series study, Poisson generalized additive models combined with distributed lag nonlinear models were used to assess the associations between ambient temperature and childhood respiratory morbidity. The impacts of extreme cold and hot temperatures were calculated as cumulative relative risks (cum.RRs) at the 1st and 99th temperature percentiles relative to the minimum morbidity temperature percentile. Attributable fractions of respiratory morbidity due to cold or heat were calculated for temperatures below or above the minimum morbidity temperature. Effect modifications by air pollution, age, and sex were assessed in stratified analyses. A total of 877,793 respiratory hospital visits of children under 14 years old between 2013 and 2017 were collected from Beijing Children's Hospital. Overall, we observed J-shaped associations with greater respiratory morbidity risks for exposure to lower temperatures, and higher fraction of all-cause respiratory hospital visits was caused by cold (33.1%) than by heat (0.9%). Relative to the minimum morbidity temperature (25 °C, except for rhinitis, which is 31 °C), the cum.RRs for extreme cold temperature (-6 °C) were 2.64 (95%CI: 1.51-4.61) for all-cause respiratory hospital visits, 2.73 (95%CI: 1.44-5.18) for upper respiratory infection, 2.76 (95%CI: 1.56-4.89) for bronchitis, 2.12 (95%CI: 1.30-3.47) for pneumonia, 2.06 (95%CI: 1.27-3.34) for rhinitis, and 4.02 (95%CI: 2.14-7.55) for asthma, whereas the associations between extreme hot temperature (29 °C) and respiratory hospital visits were not significant. The impacts of extreme cold temperature on asthma hospital visits were greater at higher levels of ozone (O₃) exposure (> 50th percentile). Our findings suggest significantly increased childhood respiratory morbidity risks at extreme cold temperature, and the impact of extreme cold temperature on asthma hospital visits can be enhanced under higher level exposure to O₃.

Climatic modification effects on the association between PM1 and lung cancer incidence in China

Background

Nationwide studies that examine climatic modification effects on the association between air pollution and health outcome are limited in developing countries. Moreover, few studies focus on PM1 pollution despite its greater health effect.

Objectives

This study aims to determine the modification effects of climatic factors on the associations between PM1 and the incidence rates of lung cancer for males and females in China.

Methods

We conducted a nationwide analysis in 345 Chinese counties (districts) from 2014 to 2015. Mean air temperature and relative humidity over the study period were used as the proxies of climatic conditions. In terms of the multivariable linear regression model, we examined climatic modification effects in the stratified and combined datasets according to the three-category and binary divisions of climatic factors. Moreover, we performed three sensitivity analyses to test the robustness of climatic modification effects.

Results

We found a stronger association between PM1 and the incidence rate of male lung cancer in counties with high levels of air temperature or relative humidity. If there is a 10 μg/m³ shift in PM1, then the change in male incidence rate relative to its mean was higher by 4.39% (95% CI: 2.19, 6.58%) and 8.37% (95% CI: 5.18, 11.56%) in the middle and high temperature groups than in the low temperature group, respectively. The findings of climatic modification effects were robust in the three sensitivity analyses. No significant modification effect was discovered for female incidence rate.

Conclusions

Male residents in high temperature or humidity counties suffer from a larger effect of PM1 on the incidence rate of lung cancer in China. Future research on air pollution-related health impact assessment should consider the differential air pollution effects across different climatic conditions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10912-8.

Long-term exposure to ambient PM2.5 and stroke mortality among urban residents in northern China

Evidence is still limited for the role of long-term PM_2.5 exposure in cerebrovascular diseases among residents in high pollution regions. The study is aimed to investigate the long-term effects of PM_2.5 exposure on stroke mortality, and further explore the effect modification of temperature variation on the PM_2.5-mortality association in northern China. Based on a cohort data with an average follow-up of 9.8 years among 38,435 urban adults, high-resolution estimates of PM_2.5 derived from a satellite-based model were assigned to each participant. A Cox regression model with time-varying exposures and strata of geographic regions was employed to assess the risks of stroke mortality associated with PM_2.5, after adjusting for individual risk factors. The cross-product term of PM_2.5 exposure and annual temperature range was further added into the regression model to test whether the long-term temperature variation would modify the association of PM_2.5 with stroke mortality. Among the study participants, the annual mean level of PM_2.5 concentration was 66.3 μg/m³ ranging from 39.0 μg/m³ to 100.6 μg/m³. For each 10 μg/m³ increment in PM_2.5, the hazard ratio (HR) was 1.31 (95% CI: 1.04-1.65) for stroke mortality after multivariable adjustment. In addition, the HRs of PM_2.5 decreased gradually as the increase of annual temperature range with the HRs of 1.95 (95% CI: 1.36-2.81), 1.53 (95% CI: 1.06-2.22), and 1.11 (95% CI: 0.75-1.63) in the low, middle, and high group of annual temperature range, respectively. The findings provided further evidence of long-term PM_2.5 exposure on stroke mortality in high-exposure settings such as northern China, and also highlighted the view that assessing the adverse health effects of air pollution might not ignore the role of temperature variations in the context of climate change.

Basic Aspects of Seasonal Cardiovascular Mortality

The review demonstrates the main aspects of seasonal cardiovascular mortality. Climatic factors, including seasonal weather changes, have a significant impact on the biosphere. People are also characterized by the seasonal dynamics of the activity of many organs and systems, biochemical parameters, and mortality. Cardiovascular mortality is also characterized by seasonal fluctuations: in winter it is maximum, in summer it is minimal. The same patterns are characteristic of mortality from cardiovascular diseases (myocardial infarction, stroke, cardiac arrhythmias, etc.). The article presents the basic patterns of seasonal cardiovascular mortality in various climatic zones, the cardiovascular mortality of countries located in the equatorial and subequatorial climatic region. In addition, the mortality displacement phenomenon, the paradox of winter mortality. The main trends in changes in cardiovascular mortality over a long period of time are demonstrated. The paper discusses some of the mechanisms that underlie the dynamics of cardiovascular mortality during the year: seasonal fluctuations in the level of vitamin D, lipids in the blood plasma, changes in hemodynamic parameters, the effects of microbial and viral infections in the cold season, etc. In addition, data on seasonal the dynamics of risk factors for cardiovascular diseases is considered: an increase in body weight, a physical activity decrease, a change in the nutrition structure in the winter, the seasonal dynamics of depression, anxiety, hostility, the relationship of seasonal cardiovascular mortality with socio-economic, demographic and other factors. In conclusion, the main ways of development and prevention of seasonal CV cardiovascular mortality M, taking into account modern technologies at the international level, for state health departments, for specific patients, are demonstrated.

Do socioeconomic factors modify the effects of PM1 and SO2 on lung cancer incidence in China?

BACKGROUND

It remains uncertain whether socioeconomic factors modify the effect of air pollution on human health. Moreover, studies investigating socioeconomic modifying roles on the effect of PM1 are quite limited, especially in developing countries.

OBJECTIVES

The present study aims to investigate socioeconomic modification effects on the associations of the incidence rate of male lung cancer with ambient PM1 and SO2 in China.

METHODS

We conducted a nationwide analysis in 345 Chinese counties (districts) between 2014 and 2015. In terms of multivariable linear regression models, we examined the modification effects of urban-rural division, education level and proportion of construction workers in the stratified and combined datasets according to the tertile and binary divisions of the three factors. Moreover, we performed three sensitivity analyses to test the robustness of socioeconomic modification effects.

RESULTS

We found a larger effect of PM1 on the incidence rate of male lung cancer in urban areas than in rural areas. The association between PM1 (or SO2) and the incidence rate of male lung cancer was stronger in counties with low education levels than in those with high education levels. The findings of the significant modification effects of urban-rural division and education level were robust in the three sensitivity analyses. No significant modification effect was observed for the proportion of construction workers.

CONCLUSIONS

Male residents in urban areas have a high risk of lung cancer incidence associated with ambient PM1. Male residents with low education levels suffer from larger effects of PM1 and SO2 on the incidence rate of lung cancer. Area- and population-specific strategies should be developed to reduce the urban-rural and educational disparities in air pollution effects, which thereby alleviates air pollution-associated health disparities in China.

Synergistic health effects of air pollution, temperature, and pollen exposure: a systematic review of epidemiological evidence

BACKGROUND

Exposure to heat, air pollution, and pollen are associated with health outcomes, including cardiovascular and respiratory disease. Studies assessing the health impacts of climate change have considered increased exposure to these risk factors separately, though they may be increasing simultaneously for some populations and may act synergistically on health. Our objective is to systematically review epidemiological evidence for interactive effects of multiple exposures to heat, air pollution, and pollen on human health.

METHODS

We systematically searched electronic literature databases (last search, April 29, 2019) for studies reporting quantitative measurements of associations between at least two of the exposures and mortality from any cause and cardiovascular and respiratory morbidity and mortality specifically. Following the Navigation Guide systematic review methodology, we evaluated the risk of bias of individual studies and the overall quality and strength of evidence.

RESULTS

We found 56 studies that met the inclusion criteria. Of these, six measured air pollution, heat, and pollen; 39 measured air pollution and heat; 10 measured air pollution and pollen; and one measured heat and pollen. Nearly all studies were at risk of bias from exposure assessment error. However, consistent exposure-response across studies led us to conclude that there is overall moderate quality and sufficient evidence for synergistic effects of heat and air pollution. We concluded that there is overall low quality and limited evidence for synergistic effects from simultaneous exposure to (1) air pollution, pollen, and heat; and (2) air pollution and pollen. With only one study, we were unable to assess the evidence for synergistic effects of heat and pollen.

CONCLUSIONS

If synergistic effects between heat and air pollution are confirmed with additional research, the health impacts from climate change-driven increases in air pollution and heat exposure may be larger than previously estimated in studies that consider these risk factors individually.

Temperature, precipitation, ozone pollution, and daily fatal unintentional injuries in Jiangsu Province, China during 2015–2017

Background

The correlation of unintentional injury mortality to rising temperatures found in several studies could result from changes in behavior that increases exposure to hazards or risk when exposed. Temperature, precipitation and air pollutants may contribute to symptoms and distractions that increase risk or avoidance behavior that reduces risk. This study examines data that allows estimates of the relation of daily maximum temperature, precipitation and ozone pollution to injury mortality risk, each corrected statistically for the correlation with the others.

Methods

Daily data on unintentional injury deaths and exposures to temperature, precipitation and ozone in 9 cities in Jiangsu Province, China during 2015–2017 were analyzed using Poisson regression. The regression estimates were adjusted for weekends, holidays, an anomalous difference in death rates in Nanjing, and population size.

Results

Non transport injury death risk increased substantially in relation to higher temperatures when temperatures were in the moderate range and even more so at temperatures 35 degrees (C) and higher. Transport deaths were related to increasing deaths when temperatures were low but the correlation reversed at higher temperatures. Deaths were lower on rainy days when temperatures were cool and moderate with the exception of non-transport injuries when temperatures were moderate. Higher ozone concentrations were associated with more deaths except when temperatures were low.

Conclusions

The variations in deaths in relation to temperature, precipitation and ozone suggest that people are behaving differently or are in different environments when specific combinations of the predictor variables are prevalent, putting them at greater or less risk. More study of the behaviors and circumstances that result in injury under those conditions is needed.

Deep learning for predicting the occurrence of cardiopulmonary diseases in Nanjing, China

The efficiency of disease prevention and medical care service necessitated the prediction of incidence. However, predictive accuracy and power were largely impeded in a complex system including multiple environmental stressors and health outcome of which the occurrence might be episodic and irregular in time. In this study, we established four different deep learning (DL) models to capture inherent long-term dependencies in sequences and potential complex relationships among constituents by initiating with the original input into a representation at a higher abstract level. We collected 504,555 and 786,324 hospital outpatient visits of grouped categories of respiratory (RESD) and circulatory system disease (CCD), respectively, in Nanjing from 2013 through 2018. The matched observations in time-series that might pose risk to cardiopulmonary health involved conventional air pollutants concentrations and metrological conditions. The results showed that a well-trained network architecture built upon long short-term memory block and a working day enhancer achieved optimal performance by three quantitative statistics, i.e., 0.879 and 0.902 of Nash-Sutcliffe efficiency, 0.921% and 0.667% of percent bias, and 0.347 and 0.312 of root mean square error-standard deviation ratio for RESD and CCD hospital visits, respectively. We observed the non-linear association of nitrogen dioxide and ambient air temperature with CCD hospital visits. Furthermore, these two environmental stressors were identified as the most sensitive predictive variables, and exerted synergetic effect for two health outcomes, particular in winter season. Our study indicated that high-quality surveillance data of atmospheric environments could provide novel opportunity for anticipating temporal trend of cardiopulmonary health outcomes based on DL model.

Modification of the effect of ambient air temperature on cardiovascular and respiratory mortality by air pollution in Ahvaz, Iran

OBJECTIVES

This study investigated the modification of temperature effects on cardiovascular and respiratory mortality by air pollutants (particulate matter less than 2.5 and 10 µm in diameter [respectively], ozone, nitrogen dioxide, carbon monoxide, and sulfur dioxide).

METHODS

Poisson additive models with a penalized distributed lag non-linear model were used to assess the association of air temperature with the daily number of deaths from cardiovascular and respiratory diseases in Ahvaz, Iran from March 21, 2014 to March 20, 2018, controlling for day of the week, holidays, relative humidity, wind speed, air pollutants, and seasonal and long-term trends. Subgroup analyses were conducted to evaluate the effect modification for sex and age group. To assess the modification of air pollutants on temperature effects, the level of each pollutant was categorized as either greater than the median value or less than/equal to the median value.

RESULTS

We found no significant associations between temperature and cardiovascular and respiratory mortality. In the subgroup analyses, however, high temperatures were significantly associated with an increased risk of cardiovascular mortality among those 75 years old and older, with the strongest effect observed on day 0 relative to exposure. The results revealed a lack of interactive effects between temperature and air pollutants on cardiovascular and respiratory mortality.

CONCLUSIONS

A weak but significant association was found between high temperature and cardiovascular mortality, but only in elderly people. Air pollution did not significantly modify the effect of ambient temperature on cardiovascular and respiratory mortality.

[Combined effects of different environmental factors on health: air pollution, temperature, green spaces, pollen, and noise]

Environmental factors affect the health and wellbeing of urban residents. However, they do not act individually on humans, but instead show potential synergistic or antagonistic effects. Questions that arise from this are: How does a combination of air pollutants with other environmental factors impact health? How well are these associations evidenced? What methods can we use to look at them? In this article, methodical approaches regarding the effects of a combination of various environmental factors are first described. Environmental factors are then examined, which together with different air pollutants, have an impact on human health such as ambient temperature, noise, and pollen as well as the effect of green spaces. Physical activity and nutrition are addressed regarding the attenuation of health effects from air pollution.While there is often clear evidence of health effects of single environmental stressors, there are still open questions in terms of their interaction. The research methods required for this still need to be further developed. The interrelationship between the different environmental factors make it clear that (intervention) measures for reducing single indicators are also interlinked. Regarding traffic, switching from passive to active transport (e.g., due to safe cycle paths and other measures) leads to less air pollutants, smaller increases in temperature in the long term, and at the same time improved health of the individual. As a result, sensible planning of the built environment has great potential to reduce environmental stressors and improve people's health and wellbeing.

The simultaneous effects of thermal stress and air pollution on body temperature of Tehran traffic officers

PURPOSE

Global warming and air pollution are among the most important problems all over the world. Considering the key role of traffic officers who saliently deal with traffic management and are in full, constant and direct exposure to thermal stress and air pollution index, this study aims to investigate the simultaneous effects of these factors on the body temperature of traffic officers in the main squares of Tehran.

METHODS

This study was conducted among 119 traffic officers who were working in 29 squares of Tehran, located near the active pollutant's stations during 2017. Samples were selected by the census method. Environmental parameters such as air temperature (dry and wet), radiation temperature, the level of air pollution in the main squares and characteristics of officers such as body temperature and the Wet-Bulb-Globe-Temperature (WBGT) index were evaluated. Data were analyzed through independent samples t-test and factorial ANOVA with a p value of p ≤ 0.05 in SPSS software.

RESULTS

There was no significant relationship between air pollution and ear temperature, but there was a statistically significant difference between the wet-bulb temperature and the ear temperature (t = 26.4, P < 0.001). The interaction effect of air pollution and wet-bulb temperature on the ear temperature was also significant (F = 3.98, P = 0.048).

CONCLUSION

Exposure to heat and air pollution affects body temperature, with its greatest impact on the temperature of the ear. More studies are recommended to be conducted in these field and other factors such as demographic and environmental factors at different times of the year should be investigated. Accordingly, some interventions should be implemented to reduce the vulnerability of officers based on the findings of the research.

Particulate matter pollution and hospital outpatient visits for endocrine, digestive, urological, and dermatological diseases in Nanjing, China

Clinical or pathological evidence demonstrated that air pollution could undermine other organ systems of human body besides respiratory and circulation systems. Investigations that directly relate hospital outpatient visits for endocrine (ENDO), digestive (DIGE), urological (UROL), and dermatological (DERM) diseases categories with ambient particulate matter (PM) are still lacking, particularly in heavily polluted cities. Here, we conducted a time-series analysis using 812,624, 1,111,342, 539,803, and 741,662 hospital visits for ENDO, DIGE, UROL, and DERM, respectively, in Nanjing, China from 2013 to 2019. A generalized additive model was applied to estimate the exposure-response associations. Results showed that a 10 μg/m³ increase in PM_2.5 concentration on lag 0 day was significantly associated with 0.59% (95% CI: 0.30%, 0.88%), 0.43% (0.15%, 0.70%), 0.36% (0.06%, 0.66%), and 0.65% (0.42%, 0.87%) increase for ENDO, DIGE, UROL, and DERM hospital visits, respectively. The estimated effects of PM₁₀ were slightly smaller but still statistically significant. The magnitude and significance of the associations between PM and four health outcomes were sensitive to additional adjustment for co-pollutants. Exposure-response relationships were linear for PM concentrations lower than 100 μg/m³ but the curves became nonlinear across the full range of exposures due to a flatten slope at higher concentrations. We also explored the effect modifications by season (cold or warm), age (5-18, 18-64, 65-74, or 75+ years), and sex (male or female). Results showed that the DERM-related population aged 65 years or older was more vulnerable to PM exposure, compared with the 5 to 17-year age group; the DERM-related population aged 75 years or older and 65 years or older was more vulnerable to PM_2.5 and PM₁₀ exposure, respectively, compared with the 18 to 64-year age group. Our study provided suggestive evidence that ambient PM pollution was associated with ENDO, DIGE, UROL, and DERM outpatient hospital visits in Nanjing, China.

Developing Vulnerability Index to Quantify Urban Heat Islands Effects Coupled with Air Pollution: A Case Study of Camden, NJ

Extreme heat events at urban centers in combination with air pollution pose a serious risk to human health. Among these are financially distressed cities and neighborhoods that are facing enormous challenges without the scientific and technical capacity for planning and mitigation. The city of Camden is one of those economically distressed areas with a predominantly minority population, a high unemployment rate, high poverty rates, and poor air quality (PM2.5 and ozone), and it remains vulnerable to heat events. This paper focuses on studying a coupled effect of Urban Heat Islands (UHIs) and Ozone-PM2.5 pollution at the neighborhood-scale in the city of Camden, using fine scale remotely sensed land-surface temperature and air quality data from the Community Multiscale Air Quality (CMAQ) Modelling System in the Geographic Information Systems (GIS) platform. To assess the impact of urban microclimate on the city of Camden, NJ, residents’ health, we identified several environmental and social parameters as the root causes of vulnerability imposed by extreme-heat and poor air quality. Vulnerability in terms of environment and social wellbeing was spatially quantified as two conceptual vulnerability-index models (i.e., environmental vulnerability index (EVI) and a social vulnerability index (SVI)) using multiple linear regression algorithm. Factors such as remotely sensed earth surface properties, built-environment components, air quality, and socio-economic data were incorporated in a holistic geographic approach to quantify the combined effect. Surface temperature gradient and Proportional Vegetation (Pv) generated from 30 m resolution Landsat 8 were sampled along with other variables in the city of Camden, NJ. Models incorporating Pv suggest better fit than models with normalized difference vegetation index (NDVI). Water fraction (33.5%, 32.4%), percentage imperviousness (32.5%, 32%), Pv (20.5%, 19.6%), and digital elevation model (DEM) (9%, 8%) have the highest contributions in both models. Two output maps identified the vulnerable neighborhoods in the city through comprehensive GIS analysis: Lanning Square, Bergen Square, Central Waterfront, Gateway, Liberty Park, and Parkside. This can provide useful information for planners and health officials in targeting areas for future interventions and mitigations.

Temperature as a modifier of the effects of air pollution on cardiovascular disease hospital admissions in Cape Town, South Africa

Climate change and air pollution are two independent risk factors to cardiovascular diseases (CVD). Few studies investigated their interaction and potential effect modification of one another in developing countries. Individual level CVD hospital admission (ICD10: I00-I99) data for 1 January 2011 to 31 October 2016 were obtained from seven private hospitals in Cape Town. NO₂, SO₂, PM₁₀, temperature and relative humidity data were obtained from the South African Weather Services and the City of Cape Town. A case-crossover epidemiological study design and conditional logistic regression model were applied. Various cut-off values were applied to classify cold and warm days. In total, 54,818 CVD hospital admissions were included in the study. In general, on warm and cold days the 15-64 years old group was more at risk for CVD hospitalization with increasing air pollution levels compared to all ages combined or the ≥ 65 years old group. Females appeared to be more at risk than males with increasing PM₁₀ levels. In contrast, males were more vulnerable to the effects of NO₂ and SO₂ than females. The study showed the modification effect of temperature on air pollution associated with CVD hospital admissions. The consideration of such interaction will help in policy making and public health interventions dealing with climate change-related health risks.

Air-Pollution Control in an Emergent Market: Does It Work? Evidence from Romania

Economic development in a national and international context must be based on a sustainability strategy established on the systemic interaction between the economic, sociocultural, and ecological environments. Today, the world is confronted by many challenges related to climate change and natural-resource flows, including waste streams resulting from economic activity. The need for national and European environmental standards and the work of an environment monitoring authority to reduce air pollution are highlighted by economic and industrial activities. Thus, our research focused on determining if emissions of sulfur dioxide (SO₂), nitrogen (NO₂), and particulate matter 10 (PM₁₀) are influenced by planned and unplanned inspections made by competent authorities from Romania. We built a regression model that estimates the influence of economic measures imposed by the authorities on reducing industrial air pollution. Preliminary results showed that the number of inspections negatively influences air pollution, indicating that national and local authorities in Romania are striving to maintain air quality and are conducting more inspections when air pollution is high.

Predicted Future Mortality Attributed to Increases in Temperature and PM10 Concentration under Representative Concentration Pathway Scenarios

As climate change progresses, understanding the impact on human health associated with the temperature and air pollutants has been paramount. However, the predicted effect on temperature associated with particulate matter (PM₁₀) is not well understood due to the difficulty in predicting the local and regional PM₁₀. We compared temperature-attributable mortality for the baseline (2003-2012), 2030s (2026-2035), 2050s (2046-2055), and 2080s (2076-2085) based on a distributed lag non-linear model by simultaneously considering assumed levels of PM₁₀ on historical and projected temperatures under representative concentration pathway (RCP) scenarios. The considered projected PM₁₀ concentrations of 35, 50, 65, 80, and 95 μg/m³ were based on historical concentration quantiles. Our findings confirmed greater temperature-attributable risks at PM₁₀ concentrations above 65 μg/m³ due to the modification effect of the pollutants on temperature. In addition, this association between temperature and PM₁₀ was higher under RCP8.5 than RCP4.5. We also confirmed regional heterogeneity in temperature-attributable deaths by considering PM₁₀ concentrations in South Korea with higher risks in heavily populated areas. These results demonstrated that the modification association of air pollutants on health burdens attributable to increasing temperatures should be considered by researchers and policy makers.

Health impact assessment by the implementation of Madrid City air-quality plan in 2020

OBJECTIVES

Air pollutant concentrations in many urban areas are still above the legal and recommended limits that are set to protect the citizens' health. Madrid is one of the cities where traffic causes high NO₂ levels. In this context, Madrid City Council launched the Air Quality and Climate Change Plan for the city of Madrid (Plan A), a local strategy approved by the previous government in 2017. The aim of this study was to conduct a quantitative health impact assessment to evaluate the number of premature deaths that could potentially be prevented by the implementation of Plan A in Madrid in 2020, at both citywide and within-city level. The main purpose was to support decision-making processes in order to maximize the positive health impacts from the implementation of Plan A measures.

METHODS

The Regional Statistical Office provided information on population and daily mortality in Madrid. For exposure assessment, we estimated PM_2.5, NO₂ and O₃ concentration levels for Madrid city in 2012 (baseline air-quality scenario) and 2020 (projected air-quality scenario based on the implementation of Plan A), by means of an Eulerian chemical-transport model with a spatial resolution of 1 km × 1 km and 30 vertical levels. We used the concentration-response functions proposed by two relevant WHO projects to calculate the number of attributable annual deaths corresponding to all non-accidental causes (ICD-10: A00-R99) among all-ages and the adult population (>30 years old) for each district and for Madrid city overall. This health impact assessment was conducted dependant on health-data availability.

RESULTS

In 2020, the implementation of Plan A would imply a reduction in the Madrid citywide annual mean PM_2.5 concentration of 0.6 μg/m³ and 4.0 μg/m³ for NO₂. In contrast, an increase of 1 μg/m³ for O₃ would be expected. The annual number of all-cause deaths from long-term exposure (95% CI) that could be postponed in the adult population by the expected air-pollutant concentration reduction was 88 (57-117) for PM_2.5 and 519 (295-750) for NO₂; short-term exposure accounted for 20 (7-32) for PM_2.5 and 79 (47-111) for NO₂ in the total population. According to the spatial distribution of air pollutants, the highest mortality change estimations were for the city centre - including Madrid Central and mainly within the M-30 ring road -, as compared to peripheral districts. The positive health impacts from the reductions in PM_2.5 and NO₂ far exceeded the adverse mortality effects expected from the increase in O₃.

CONCLUSIONS

Effective implementation of Plan A measures in Madrid city would bring about an appreciable decline in traffic-related air-pollutant concentrations and, in turn, would lead to significant health-related benefits.

Modification Effects of Temperature on the Ozone-Mortality Relationship: A Nationwide Multicounty Study in China

Both ozone exposure and extreme temperatures are found to be significantly associated with mortality; however, inconsistent results have been obtained on the modification effects of temperature on the ozone-mortality association. In the present study, we conducted a nationwide time-series analysis in 128 counties from 2013-2018 to examine whether temperature modifies the association between short-term ozone exposure with nonaccidental and cause-specific mortality in China. First, we analyzed the effects of ozone exposure on mortality at different temperature levels. Then, we calculated the pooled effects through a meta-analysis across China. We found that high-temperature conditions (>75th percentile in each county) significantly enhanced the effects of ozone on nonaccidental, cardiovascular, and respiratory mortality, with increases of 0.44% (95% confidence interval (CI): 0.36 and 0.51%), 0.42% (95% CI: 0.32 and 0.51%) and 0.50% (95% CI: 0.31 and 0.68%), respectively, for a 10 μg/m³ increase in ozone at high temperatures. Stronger effects on nonaccidental and cardiovascular mortality were observed at high temperatures among elderly individuals aged 65 years and older compared with the younger people. Our findings provide evidence that health damage because of ozone may be influenced by the impacts of increasing temperatures, which point to the importance of mitigating ozone exposure in China under the context of climate change to further reduce the public health burden.

Climate change and the projected burden of future health impacts – The Project EXHAUSTION

Climate change, foreseen to cause adverse effects on human health, is an emerging global public health threat. Several studies have projected an increasing burden of health effects in the future as a result of global warming. Nevertheless, research in this field is comparatively young and so far there are no concrete answers about the future climate change related health impacts. This article discusses existing research gaps and introduces the EU project EXHAUSTION which aims to fill at least some of them.

Ambient PM2.5 and Annual Lung Cancer Incidence: A Nationwide Study in 295 Chinese Counties

Most studies have examined PM2.5 effects on lung cancer mortalities, while few nationwide studies have been conducted in developing countries to estimate the effects of PM2.5 on lung cancer incidences. To fill this gap, this work aims to examine the effects of PM2.5 exposure on annual incidence rates of lung cancer for males and females in China. We performed a nationwide analysis in 295 counties (districts) from 2006 to 2014. Two regression models were employed to analyse data controlling for time, location and socioeconomic characteristics. We also examined whether the estimates of PM2.5 effects are sensitive to the adjustment of health and behaviour covariates, and the issue of the changing cancer registries each year. We further investigated the modification effects of region, temperature and precipitation. Generally, we found significantly positive associations between PM2.5 and incidence rates of lung cancer for males and females. If concurrent PM2.5 changes by 10 g/m³, then the incidence rate relative to its baseline significantly changes by 4.20% (95% CI: 2.73%, 5.88%) and 2.48% (95% CI: 1.24%, 4.14%) for males and females, respectively. The effects of exposure to PM2.5 were still significant when further controlling for health and behaviour factors or using 5 year consecutive data from 91 counties. We found the evidence of long-term lag effects of PM2.5. We also found that temperature appeared to positively modify the effects of PM2.5 on the incidence rates of lung cancer for males. In conclusion, there were significantly adverse effects of PM2.5 on the incidence rates of lung cancer for both males and females in China. The estimated effect sizes might be considerably lower than those reported in developed countries. There were long-term lag effects of PM2.5 on lung cancer incidence in China.

Ambulance Services Associated with Extreme Temperatures and Fine Particles in a Subtropical Island

This study evaluated the association between the risk of events requiring ambulance services and the ambient temperature and particulate matter of 2.5 μm (PM_2.5) and 10 μm (PM₁₀) for populations living in subtropical Taiwan. We used a distributed lag nonlinear model with a quasi-Poisson function to assess the roles of ambient temperature, PM₁₀ and PM_2.5 in the use of ambulance services for respiratory distress, coma and unconsciousness, chest pain, lying down in public, headaches/dizziness/vertigo/fainting/syncope and out-of-hospital cardiac arrest (OHCA). The relative risk (RR) and 95% confidence interval (CI) of each specific event were calculated in association with the ambient conditions. In general, the events that required ambulance services had a V-shaped or J-shaped association with the temperature, where the risks were higher at extreme temperatures. The RR of each event was significant when the patients were exposed to temperatures in the 5^th percentile (<15 °C); patients with OHCA had the highest adjusted RR of 1.61 (95% CI = 1.47–1.77). The risks were also significant for coma/unconsciousness, headaches/dizziness/vertigo/fainting/syncope, and OHCA but not for respiratory distress, chest pain and lying down in public, after exposure to the 99^th percentile temperatures of >30 °C. The risks for use of ambulance services increased with PM exposure and were significant for events of respiratory distress, chest pain and OHCA after exposure to the 99^th percentile PM_2.5 after controlling for temperatures. Events requiring ambulance services were more likely to occur when the ambient temperature was low than when it was high for the population on the subtropical island of Taiwan. The association of the risk of events requiring ambulance services with PM were not as strong as the association with low temperatures.

Short-Term Associations of Fine Particulate Matter and Synoptic Weather Types with Cardiovascular Mortality: An Ecological Time-Series Study in Shanghai, China

Background: Exposures to both ambient fine particulate matter (PM_2.5) and extreme weather conditions have been associated with cardiovascular disease (CVD) deaths in numerous epidemiologic studies. However, evidence on the associations with CVD deaths for interaction effects between PM_2.5 and weather conditions is still limited. This study aimed to investigate associations of exposures to PM_2.5 and weather conditions with cardiovascular mortality, and further to investigate the synergistic or antagonistic effects of ambient air pollutants and synoptic weather types (SWTs). Methods: Information on daily CVD deaths, air pollution, and meteorological conditions between 1 January 2012 and 31 December 2014 was obtained in Shanghai, China. Generalized additive models were used to assess the associations of daily PM_2.5 concentrations and meteorological factors with CVD deaths. A 15-day lag analysis was conducted using a polynomial distributed lag model to access the lag patterns for associations with PM_2.5. Results: During the study period, the total number of CVD deaths in Shanghai was 59,486, with a daily mean of 54.3 deaths. The average daily PM_2.5 concentration was 55.0 µg/m³. Each 10 µg/m³ increase in PM_2.5 concentration was associated with a 1.26% (95% confidence interval (CI): 0.40%, 2.12%) increase in CVD mortality. No SWT was statistically significantly associated with CVD deaths. For the interaction between PM_2.5 and SWT, statistically significant interactions were found between PM_2.5 and cold weather, with risk for PM_2.5 in cold dry SWT decreasing by 1.47% (95% CI: 0.54%, 2.39%), and in cold humid SWT the risk decreased by 1.45% (95% CI: 0.52%, 2.36%). In the lag effect analysis, statistically significant positive associations were found for PM_2.5 in the 1-3 lag days, while no statistically significant effects were found for other lag day periods. Conclusions: Exposure to PM_2.5 was associated with short-term increased risk of cardiovascular deaths with some lag effects, while the cold weather may have an antagonistic effect with PM_2.5. However, the ecological study design limited the possibility to identify a causal relationship, so prospective studies with individual level data are warranted.

Impact of Environmental Regulations on Environmental Quality and Public Health in China: Empirical Analysis with Panel Data Approach

Achieving high-quality environmental development through environmental regulations and thus enhancing public health is a goal of the Chinese government. Based on the panel data of 30 Chinese provinces from 1998 to 2017, this study demonstrates the co-benefits of environmental regulations on air quality, water, and public health through a panel Granger causality model and mediation effect model. The findings indicate that environmental regulations have a Granger causal effect on public health costs and air and water pollution. Furthermore, the results from the mediation effect model suggest that waste gas treatment could improve air quality, thus reducing public health costs; wastewater treatments could not only reduce public health costs through improvement of the water environment but also increase social welfare. Additionally, air pollution exhibits a greater negative externality impact on health than water pollution. Thus, environmental regulation policies should pay more attention to air pollution control. The findings of this study indicate that environmental regulations have a significant co-benefit on high-quality environmental development and public health.

Hourly Exposure to Ultrafine Particle Metrics and the Onset of Myocardial Infarction in Augsburg, Germany

BACKGROUND

Epidemiological evidence on the health effects of ultrafine particles (UFP) remains insufficient to infer a causal relationship that is largely due to different size ranges and exposure metrics examined across studies. Moreover, evidence regarding the association between UFP and cardiovascular disease at a sub-daily timescale is lacking.

OBJECTIVE

We investigated the relationship between different particle metrics, including particle number (PNC), length (PLC), and surface area (PSC) concentrations, and myocardial infarction (MI) at an hourly timescale.

METHODS

We collected hourly air pollution and meteorological data from fixed urban background monitoring sites and hourly nonfatal MI cases from a MI registry in Augsburg, Germany, during 2005-2015. We conducted a time-stratified case-crossover analysis with conditional logistic regression to estimate the association between hourly particle metrics and MI cases, adjusted for air temperature and relative humidity. We also examined the independent effects of a certain particle metric in two-pollutant models by adjusting for copollutants, including particulate matter (PM) with an aerodynamic diameter of ≤10μm or 2.5μm (PM10 and PM2.5, respectively), nitrogen dioxide, ozone, and black carbon.

RESULTS

Overall, a total of 5,898 cases of nonfatal MI cases were recorded. Exploratory analyses showed similar associations across particle metrics in the first 6-12 h. For example, interquartile range increases in PNC within the size range of 10-100 nm, PLC, and PSC were associated with an increase of MI 6 h later by 3.27% [95% confidence interval (CI): 0.27, 6.37], 5.71% (95% CI: 1.79, 9.77), and 5.84% (95% CI: 1.04, 10.87), respectively. Positive, albeit imprecise, associations were observed for PNC within the size range of 10-30 nm and 100-500 nm. Effect estimates for PLC and PSC remained similar after adjustment for PM and gaseous pollutants.

CONCLUSIONS

Transient exposure to particle number, length, and surface area concentrations or other potentially related exposures may trigger the onset of nonfatal myocardial infraction. https://doi.org/10.1289/EHP5478.

Effect of changes in season and temperature on cardiovascular mortality associated with nitrogen dioxide air pollution in Shenzhen, China

BACKGROUND

The intricate association of mortality risk with ambient air pollution and temperature is of growing concern. Little is known regarding effect of changes in season and temperature on daily cardiovascular mortality associated with air pollutant nitrogen dioxide (NO₂).

OBJECTIVES

Our study aimed to assess the effect of NO₂ on cardiovascular mortality modified by season and daily air temperature in the effect, and further to identify the population highly susceptible to cardiovascular mortality associated with NO₂ and air temperature.

METHODS

We collected daily cause-specific death data, weather conditions, and air pollutant concentrations in Shenzhen from 2013 to 2017. Distributed-lag linear models were employed to analyze the effect of season on the NO₂-associated mortality. Furthermore, generalized additive models were combined with stratification parametric analysis to estimate the interaction effect of NO₂ with air temperature on cardiovascular mortality.

RESULTS

In the cold season, the percentage increase in daily mortality for every 10 μg/m³ increment in NO₂ concentration over lags of 0-2 days was 4.45% (95% CI: 2.71-6.21%). However, no statistically significant effect of NO₂ was observed in the warm season. Compared with high-temperature days (>median temperature), a 3.51% increase in mortality (95% CI: 2.04-5.01%) over low-temperature days (≤median temperature) for the same increase in NO₂ was significant. Air temperature modified the effect of NO₂ on daily mortality by 4.08% (95% CI: 2.28-5.91%) for the elderly (age ≥ 65 years) on low-temperature days vs. -0.82% (95% CI: -3.88-2.34%) on high-temperature days, and 3.38% (95% CI: 1.50-5.29%) for males on low-temperature days vs. -0.73% (95% CI: -3.83-2.47%) on high air temperature days.

CONCLUSIONS

The cold season and low temperatures could significantly enhance the effect of NO₂ on cardiovascular mortality. The elderly and males suffering from cardiovascular disease should take precautions against low temperature and NO₂ air pollution.

Short-term effects of ambient air pollution and outdoor temperature on biomarkers of myocardial damage, inflammation and oxidative stress in healthy adults

Supplemental Digital Content is available in the text.

The mechanisms whereby ambient air pollution and temperature changes promote cardiac events remain incompletely described. Seventy-three nonsmoking healthy adults (mean age 23.3, SD 5.4 years) were followed with up to four repeated visits across 15 months in Beijing in 2014–2016. Biomarkers relevant to myocardial damage (high-sensitivity cardiac troponin I [hs-cTnI]), inflammation (growth differentiation factor-15 [GDF-15]), and oxidative stress (8-hydroxy-2′-deoxyguanosine [8-OHdG]) were measured at each visit, while ambient air pollution and temperature were monitored throughout the study. Linear mixed-effects models coupled with distributed lag nonlinear models were used to assess the impacts of each exposure measure on study outcomes. During follow-up, average daily concentrations of fine particulate matter and outdoor temperature were 62.9 µg/m³ (8.1–331.0 µg/m³) and 10.1 °C (−6.5°C to 29.5°C). Serum hs-cTnI levels were detectable in 18.2% of blood samples, with 27.4% of individuals having ≥1 detectable values. Higher levels of ambient particulates and gaseous pollutants (per interquartile range) up to 14 days before clinical visits were associated with significant alterations in hs-cTnI levels of 22.9% (95% CI, 6.4, 39.4) to 154.7% (95% CI, 94.4, 215.1). These changes were accompanied by elevations of circulating GDF-15 and urinary 8-OHdG levels. Both low (5th percentile, −2.5 °C) and high (95th percentile, 24.8°C) outdoor temperatures, with breakpoint at ~13.0°C as the reference level, were also associated with elevations of hs-cTnI levels. Short-term exposure to ambient air pollution and temperature was associated with cardiac troponin, a biomarker of myocardial damage, along with increased inflammation and oxidative stress responses. These findings extend our understanding of the biological mechanisms linking pervasive environmental exposure to adverse cardiac events.

Impact of weather changes on air quality and related mortality in Spain over a 25 year period [1993-2017]

Climate change is a major public health concern. In addition to its direct impacts on temperature patterns and extreme weather events, climate change affects public health indirectly through its influence on air quality. Pollution trends are not only affected by emissions changes but also by weather changes. In this paper we analyze air quality trends in Spain of important air pollutants (C₆H₆, CO, NO₂, NO_x, O₃, PM₁₀, PM_2.5, and SO₂) recorded during the last 25 years, from 1993 to 2017. We found substantial reductions in ambient concentration levels for all the pollutants studied except for O₃. To assess the influence of recent weather changes on air quality trends we applied generalized additive models (GAMs) using nonparametric smoothing; with and without adjusting for weather parameters including temperature, wind speed, humidity and precipitation frequency. The difference of annual slopes estimated by the models without and with adjusting for these meteorological variables represents the impact of weather changes on pollutant trends, i.e. the 'weather penalty'. The analyses were seasonally and geographically stratified to account for temporal and regional differences across Spain. The results were meta-analyzed to estimate weather penalties on ambient concentration trends at a national level as well as the impact on mortality for the most relevant pollutants. We found significant penalties for most pollutants, implying that air quality would have improved even more during our study period if weather conditions had remained constant. The largest weather influences were found for PM₁₀, with seasonal penalties up to 22 μg⋅m^-3 accumulated over the 25-year period in some regions. The national meta-analysis shows penalties of 0.060 μg⋅m^-3 per year (95% Confidence Interval, CI: 0.004, 0.116) in cold months and 0.127 μg⋅m^-3 per year (95% CI: 0.089, 0.164) in warm months. Penalties of this magnitude would correspond to 129 annual deaths (95% CI: 25, 233), i.e. approximately 3200 deaths over the 25-year period in Spain. According to our results, the health benefits of recent emission abatements for this pollutant in Spain would have been up to 10% greater if weather conditions had remained constant during the last 25 years.

A Case-Crossover Study to Investigate the Effects of Atmospheric Particulate Matter Concentrations, Season, and Air Temperature on Accident and Emergency Presentations for Cardiovascular Events in Northern Italy

Atmospheric particulate matter (PM) has multiple adverse effects on human health, high temperatures are also associated with adverse health outcomes, and the frequency of cardiovascular events (CVEs) varies with season. We investigated a hypothesized increase in PM-related accident and emergency (A&E) presentations for CVE with high temperature, warm season, days of high influenza incidence, and in people with a cancer diagnosis, using a time-stratified case-crossover study design. Outcomes were associations of A&E presentation for CVE with atmospheric PM ≤ 10 μm (PM₁₀), season, and air temperature. PM₁₀ levels in the municipality of residence (exposure variable) were estimated by modeling data from local monitoring stations. Conditional logistic regression models estimated odds ratios (OR) with 95% confidence intervals (CI) for presentations in relation to supposed influencers, adjusting for confounders. Study participants were all who presented at the A&E of a large hospital near Milan, Italy, for a CVE (ICD-9: 390–459) from 1st January 2014 to 31st December 2015. There were 1349 A&E presentations for CVE in 2014–2015 and 5390 control days. Risk of A&E presentation was significantly increased on hot days with OR 1.34 (95%CI 1.05–1.71) per 10 μg/m³ PM₁₀ increment (as mean PM₁₀ on day of presentation, and 1 and 2 days before (lags 0–2)), and (for lag 0) in autumn (OR 1.23, 95%CI 1.09–1.37) and winter (OR 1.18, 95%CI 1.01–1.38). Risks were also significantly increased when PM₁₀ was on lag 1, in people with a cancer diagnosis in the spring and summer months (1.88, 95%CI 1.05–3.37), and on days (lags 0–2) of high influenza incidence (OR 2.34, 95%CI 1.01–5.43). PM₁₀ levels exceeded the 50 μg/m³ “safe” threshold recommended by the WHO and Italian legislation for only 3.8% of days during the warm periods of 2014–2015. Greater risk of A&E presentation for CVE in periods of high PM₁₀ and high temperature suggests that “safe” thresholds for PM₁₀ should be temperature-dependent and that the adverse effects of PM₁₀ will increase as temperatures increase due to climate change.