Particulate air pollution is a continuing challenge in China, and its adverse effects on chronic obstructive pulmonary disease (COPD) have been widely reported. However, epidemiological evidence on the associations between size-fractionated particle number concentrations (PNCs) and COPD mortality is limited. In this study, we utilized a time-series approach to investigate the associations between PNCs of particles at 0.25–10 μm in diameter and COPD mortality in Shanghai, China. Quasi-Poisson regression generalized additive models were applied to evaluate these associations, with adjustment of time trend, day of week, holidays, temperature and relative humidity. Stratification analyses were performed by season and gender. There were a total of 3238 deaths due to COPD during the study period. We found that daily COPD deaths were significantly associated with PNCs of particles <0.5 μm, and the magnitude of associations increased with decreasing particle size. An interquartile range (IQR) increase in PNC₀.₂₅—₀.₂₈, PNC₀.₂₈—₀.₃, PNC₀.₃—₀.₃₅, PNC₀.₃₅—₀.₄, PNC₀.₄—₀.₄₅ and PNC₀.₄₅—₋₀.₅ was associated with increments of 7.51% (95%CI: 2.45%, 12.81%), 7.22% (95%CI: 2.16%, 12.53%), 6.95% (95%CI: 1.81%, 12.35%), 6.26% (95%CI: 1.25%, 11.52%), 5.24% (95%CI: 0.56%, 10.13%) and 4.15% (95%CI: 0.14%, 8.32%), respectively. The associations remained robustness after controlling for the mass concentrations of gaseous air pollutants. In stratification analyses, significant associations between PNCs and COPD mortality were observed in the cold seasons, and in males. Our results suggested that particles <0.5 μm in diameter might be most responsible for the adverse effects of particulate air pollution on COPD mortality, and COPD patients are more susceptible to PM air pollution in the cold seasons, especially for males.

This study aimed to provide a comprehensive characterisation of the indoor air quality during the sleeping period of 10 couples at Lisbon dwellings, using a multi-pollutant approach, and to understand how the compliance with legislation and guidelines was to assure a good indoor air quality. The assessment of indoor air quality was conducted in the cold season using real time monitors during the sleeping period for comfort parameters (temperature and relative humidity) and air pollutants (carbon dioxide – CO₂, carbon monoxide – CO, formaldehyde – CH₂O, total volatile organic compounds – VOCs, and particulate matter – PM₂.₅ and PM₁₀), together with active sampling of bioaerosols (fungi and bacteria) before and after the sleeping period. Lower compliance (less than 50% of the cases) with the Portuguese legislation was found for temperature, CO₂ (3440 ± 1610 mg m⁻³), VOCs (1.79 ± 0.99 mg m⁻³) and both bioaerosol types. In 70% of the cases, PM₂.₅ (15.3 ± 9.1 μg m⁻³) exceeded the WHO guideline of 10 μg m⁻³. All bedrooms presented air change rates above the recommended minimum value of 0.7 h⁻¹, highlighting that a good indoor air quality during sleep is not guaranteed.

Marine fishes are exposed to great human-induced alterations due to the indiscriminate discharges into the sea, increasing marine pollution. For this study, 324 specimens of Sardina pilchardus from the Canary Islands were analized during a period of 2 years (June 2016 to May 2018). The concentration of 11 metals and trace elements (Al, B, Cd, Cr, Cu, Fe, Li, Ni, Pb, V and Zn) was determined in each individual using the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. Statistical analyses were carried out considering the following factors: oceanographic season, maturity of the gonads in the seasons, size of the specimens. Sardina pilchardus specimens captured in the hot season presented higher Ni, Li and Pb levels than the specimens caught in the cold season. Immature specimens had higher concentration in more metals than the mature specimens. This fact may be due to the fact that these specimens require a much higher metabolic rate due to their growth and do not detoxify like mature specimens. Significant differences were found in the concentration of metals in all the analyzes performed.

Odor concentrations (OC) and emissions (OE) were measured for a commercial broiler barn and a cage-layer barn in a cold region (the Canadian Prairies). Seasonal OC and OE profiles were plotted by monthly measurements over the course of a year from March 2015 to February 2016, and diurnal profiles were generated by 2-day measurements in cold, mild, and warm seasons, respectively. Seasonal OC and OE varied for both barns; OC was higher in the cold season, but OE was higher in the mild and warm seasons. The broiler barn had higher annual average OC (718 OU m⁻³) but slightly lower annual average OE (127 OU s⁻¹ AU⁻¹; AU is per 500 kg of body mass) than the layer barn (574 OU m⁻³ and 140 OU s⁻¹ AU⁻¹). For the layer barn, OC and OE were reduced by 31% and 33% in the cold season and by 30% and 26% in the mild season after manure removal compared with before manure removal. Statistical results showed increased outdoor temperature and ventilation rate (VR) were associated with decreased OC but increased OE for both barns. Finally, both single linear and multi-linear regression models of OE were developed.

Several epidemiological studies have investigated the adverse health effects of air pollution, but studies reporting its effects on allergic rhinitis (AR) are limited, especially in developing countries having the most severe pollution. Limited studies have been conducted in China, but their results were inconsistent. So, we conducted a time-series study to evaluate the acute effect of six air pollutants (fine particulate matter [PM₂.₅], particulate matter with diameter less than 10 μm [PM₁₀], sulfur dioxide [SO₂], nitrogen dioxide [NO₂], ozone [O₃], and carbon monoxide [CO]) on hospital outpatient visits for AR in Xinxiang, China from January 1, 2015, to December 31, 2018. An over-dispersed Poisson generalized additive model adjusting for weather conditions, long-term trends, and day of the week was used. In total, 14,965 AR outpatient records were collected during the study period. Results found that each 10 μg/m³ increase in PM₂.₅, PM₁₀, SO₂, NO₂, O₃, and CO corresponded to 0.70% (95% confidence interval 0.00–1.41%), 0.79% (0.35–1.23%), 3.43% (1.47–5.39%), 4.54% (3.01–6.08%), 0.97% (− 0.11–2.05%), and 0.07% (0.02–0.12%) increments in AR outpatients on the current day, respectively. In the stratification analyses, statistically stronger associations were observed with PM₂.₅, PM₁₀, SO₂, NO₂, and CO for AR outpatients < 15 years of age than in those 15–65 and ≥ 65 years of age, whereas the opposite result was found with O₃. Associations between PM₁₀, SO₂, NO₂, O₃, and AR outpatients were higher in the warm season than those in the cool season. This study suggests that exposure to PM₂.₅, PM₁₀, SO₂, NO₂, and CO was associated with increased AR risk and children younger than 15 years might be more vulnerable.

Ambient air pollution (AAP) has been widely associated with increased morbidity of ischemic heart disease (IHD). However, no prior studies have investigated the effects of AAP exposure on the length of stay (LOS) due to IHD. Hospital data during 2015–2017 were obtained from hospital information system in five cities of Hubei province, China. We collected daily mean concentrations of air pollutants, including PM₂.₅, PM₁₀, SO₂, NO₂, O₃, and CO, and meteorological data during the same time period. Poisson regression was applied to estimate the acute impacts of AAP on the LOS of IHD inpatients. A total of 42,114 inpatients with primary diagnosis of IHD were included, 50.63% of which were chronic IHD inpatients. Annual average concentrations of PM₂.₅, PM₁₀, SO₂, NO₂, O₃, and CO were 61.93 μg/m³, 95.47 μg/m³, 18.59 μg/m³, 35.87 μg/m³, 100.30 μg/m³, and 1.117 mg/m³, respectively. After adjusting for temperature, relative humidity, gender, age group, payment method, number of hospital beds, location of hospital, and surgery or not, exposures to PM₂.₅, PM₁₀, SO₂, O₃, and CO were associated with increased LOS for all IHD patients in both single- and multi-pollutant models, and stronger associations were observed among chronic IHD patients. In addition, subgroup analyses demonstrated that males and the group aged 65+ years were more vulnerable to air pollution, and the adverse effects were also promoted by low temperature in cold season. This study provides the first investigation of the adverse effects of AAP on the LOS for IHD patients. In order to shorten the LOS of IHD, measures should be taken to strengthen the AAP management and protect the high-risk population.

Sudden temperature changes between neighboring days (T₂₄ₕ) have adverse effects on human health. In this study, we used a time series analysis to evaluate the impact of T₂₄ₕ on the number of hospital admissions for chronic obstructive pulmonary disease (COPD) from 2009 to 2012 in Changchun (the capital of Northeast China’s Jilin province). We performed the analysis in a generalized additive model (GAM), and the controlling factors included long-term trends, day of the week effect, and the selected weather elements. We divided the entire study group into two gender subgroups (males and females) and two age subgroups (aged < 65 years and aged ≥ 65 years). T₂₄ₕ showed the greatest effect on the entire study group at lag 3 days. In particular, the greatest effect of T₂₄ₕ on females (males) occurred at lag 1 day (lag 3 days); the greatest effect of T₂₄ₕ on the aged ≥ 65 years (aged < 65 years) occurred at lag 1 day (lag 6 days). This indicates that temperature changes between neighboring days have a relatively more acute effect on the elderly and the females than on the younger people and the males. When T₂₄ₕ is less than zero, the highest RR of the number of hospital admissions for COPD occurred at lag 4 days during the warm season (1.025, 95% CI: 0.981, 1.069) and lag 3 days during the cold season (1.019, 95% CI: 0.988, 1.051). When T₂₄ₕ is greater than zero, the highest RR of the number of hospital admissions for COPD occurred at lag 6 days during the warm season (1.026, 95% CI: 0.977, 1.077) and lag 5 days during the cold season (1.021, 95% CI: 0.986, 1.057). The results of this study could be provided to local health authorities as scientific guidelines for controlling and preventing COPD in Changchun, China.

This study was concerned with the temporal analysis of benzene, toluene, ethylbenzene, xylenes (BTEXs), and ozone in Rochester, New York, between 2012 and 2018. Additionally, the influence of ozone precursors (e.g., BTEXs and NO₂) and meteorological variables (e.g., relative humidity (RH), temperature along with wind speed) on ozone dispersion was investigated in the eastern half of the USA using the integrated nested Laplace approximation and stochastic partial differential equation (INLA-SPDE). The benzene variability at seasonal scale was characterized by higher values during the cold seasons. On the contrary, the long-term temporal trend of ozone depicted a repetitive cyclic behavior while an episode, with values exceeding 5 μg/m³, was detected associated with benzene in 2015. The spatial analysis by INLA-SPDE indicated that 1,3,5-trimethylbenzene and benzene were the key ozone precursors influencing ozone formation. It was demonstrated that increase of temperature had a considerable impact on ozone build-up whereas the increment of RH leads to decrease in ambient values of ozone. The amounts of root mean squared error (RMSE), mean absolute error (MAE), and bias for the validation data (e.g., 32 samples) were 0.005, 0.004, and 0.0008, exhibiting a reasonable out-of-sample forecasting by the INLA-SPDE model. The distribution map of ozone highlighted a hot spot in the state of Florida.

Ambient particulate matter is one of the main risk factors of chronic obstructive pulmonary disease (COPD) in developing countries. However, the studies were scant in China concerning the health effects of the fine particulate matter (PM₂.₅; particulate matter ≤ 2.5 μm in diameter) on hospital visits for COPD. We applied a generalized additive model (GAM) to calculate relative risks (RRs) with 95% confidence intervals (CIs) for the associations between hospital visits for COPD and an interquartile range (24.50 μg/m³) increment of ambient PM₂.₅ concentrations in Yinzhou District between 2016 and 2018. The ambient PM₂.₅ concentration was positively associated with hospital visits for COPD at a distributed lag of 0–7 days (RR = 1.073, 95% CI, 1.016, 1.133). In the stratified analysis, we found that the association between ambient PM₂.₅ and COPD was stronger during the warm season (April to September) than that during the cold season (October to March), but we did not observe statistically significant differences in age groups (< 60 years and ≥ 60 years) or gender groups (male and female) related to the effects of PM₂.₅. The associations between ambient PM₂.₅ and COPD became partially attenuated after the adjustment for gaseous pollutants in subgroups. Our findings could provide evidence that regulations for controlling both PM₂.₅ and gaseous pollutants should be implemented to protect the overall population.

Cardiovascular disease (CVD) has been the leading cause of death in China. Identifying the relationship between particulate matter (PM) and CVD in China is a significant challenge. In this study, daily CVD emergency room visit, environmental monitoring, and weather data from January 1, 2017, to December 31, 2018, in Lanzhou were collected. Generalized additive models (GAMs) were constructed to estimate the short-term effects of daily PM₂.₅, PMC, and PM₁₀ concentrations on CVD emergency room visits with different lag structures after controlling for the influence of meteorological elements and gaseous pollutants. Stratified analyses were conducted according to age (≥ 65 years and < 65 years), sex (male and female), cold season (from November to April), and warm season (from May to October). The results showed that each 10 μg/m³ increase in PM₂.₅ was associated with a 1.93% (95% CI 0.12–3.78%) increase in CVD emergency room visits at lag03, and no single lag model was statistically significant. The excess relative risks (ERRs) of PM₁₀ and PMC were not statistically significant at any lag pattern. The exposure-response curves demonstrated a nonlinear upward trend for these three PM pollutants. When adjusting for other gaseous pollutants, such as NO₂, SO₂, CO, and O₃, in the two-pollutant models, the associations between PM₁₀ and PMC and CVD emergency room visits did not change compared with the single-pollutant models. The ERRs of PM₂.₅ were 1.67% (95% CI 0.03–3.34%) at lag02 after adjustment for NO₂ and 1.65% (95% CI 0.02–3.30%) at lag02 after adjustment for SO₂. The ERRs of PM₂.₅ were still statistically significant at lag03 when we adjusted for any one of the gaseous pollutants. Susceptibility to PM₂.₅ was increased in people aged < 65 years, in males, and in the warm season. The findings are very important for local governments to develop environmental policies and strategies to reduce ambient PM₂.₅ levels.