Air Quality Atmosphere and Health最新文献

To investigate the associations between particulate matter (PM) and hospital admissions for stroke and its subtypes among hypertension patients. We proposed a new modifier named high-concentration duration (HCD). Data on daily hospital admissions, air pollution, and meteorological factors were collected from 2014 to 2018 in Beijing, China. We included all patients with hypertension who were admitted to hospitals of secondary-level and above for stroke. Time-series analysis was conducted by fitting a generalized additive model. An interaction term of daily concentration and an HCD stratum indicator were included in the model. Sex subgroup analysis was performed in four age groups to detect vulnerable populations. A total of 358,577 admissions were identified. The PM was significantly associated with stroke admissions in patients with hypertension. The maximum excess risk (ER) (%) per 10 μg/m³ increase in fine particulate matter (PM_2.5) was 0.23% (95% confidence interval (CI): 0.15%, 0.31%) for overall stroke, 0.25% (95% CI: 0.16%, 0.33%) for ischemic stroke (IS). The maximum ER (%) per 10 μg/m³ increase in inhalable particle (PM₁₀) was 0.14% (95% CI: 0.06%, 0.23%) for overall stroke, 0.15% (95% CI: 0.06%, 0.23%) for IS. For hemorrhagic stroke, significant associations were also observed among males and patients < 55 years. ER (%) in long-HCD strata was significantly larger than that in short-HCD strata. The effects of PM_2.5 were significant in long-HCD strata, but insignificant in short-HCD strata. HCD might be a modifier in the association between air pollution and health effects. While controlling the daily average concentration, it is also important to reduce HCD on a given day.

The evidence of non-optimum ambient temperature and humidity-related mortality is widely reported. However, the joint effects of high humidity and extreme temperatures on mortality remain to understand. We collected mortality data and meteorological variables for 91 counties in central China, from 2017 to 2020. A traditional time-series model with a distributed lag non-linear model was first employed to estimate the location-specific associations between extreme temperatures or high humidity and extreme temperatures and mortality. Then, we conducted a meta-analysis to pool the county-specific estimated effect values. A total of 1,196,916 non-accidental deaths occurred during the study period. Extreme heat increased non-accidental mortality with a relative risk (RR) of 1.071 ((95% confidence interval (CI):1.022, 1.121), while extreme cold worsened the risk of stroke mortality by 2.817 (95 CI%: 1.084, 7.321). For the effect of extreme cold, high humidity increased the RR of 3.908 (95 CI%: 2.721, 5.612) in non-accidental mortality and the effect was strongest in stroke with 5.320 (95 CI%: 3.395 vs 8.338). Under the joint effect of extreme cold and high humidity, there is a lagged association with the mortality risks peaked at 12d for non-accidental mortality. High humidity significantly enhances the risk of extreme cold-related non-accidental mortality, especially regarding stroke. Our findings will assist in the development of preparedness and prevention strategies in Hunan Province and even throughout China to reduce the immediate weather-related impacts.

Extremely low frequency oscillating magnetic field (OMF-ELF) can stimulate the growth of pathogenic fungi. This work aims to assess the tropic response of a dimorphic pathogenic strain Candida guilliermondii by the effect of OMF-ELF. The pathogenic strain C. guilliermondii was isolated from an indoor environment and a brewing strain Saccharomyces cerevisiae was used as a positive control. OMF-ELF of 3 mT of 60 Hz for 2 h was applied to the cultures of both strains. After treatment, images were taken every 30 min for 24 h using Digital Image Processing (DIP) to determine the superficial growth rate of both strains and the length of the pseudohyphae, and the tropic response of C. guilliermondii. However, C. guilliermondii showed a tropic response depending on the OMF-ELF applied growing 3 to 60 times faster than the control strain, with a maximum value of 1.27 μm²/min between 1.5 and 2.5 h. C. guillermondii is resistant to OMF-ELF, a factor that stimulated its superficial growth rate and the elongation of its pseudohyphae, facilitated its cellular dimorphism, and oriented its ramifications to increase reproduction. This increase constitutes a risk to human health indoor environments where there is microbiological and electromagnetic contamination. Due to the use of DIP in real time with an adapted microculture technique, this is the first study to analyze “in vivo” magnetotropism of C. guilliermondii, as indicative of its invasive behavior for a possible infestation to humans exposed to this type of non-ionizing radiation in an indoor environment.

Polycyclic aromatic hydrocarbons (PAHs) were measured in size-segregated particulate matters (PMs) in a range of 0.43 to 10.0 μm, categorized into two as fine particles (0.43 μm < d < 2.1 μm) and coarse particles (2.1 μm < d < 10.0 μm), during summer and winter seasons in an urban atmosphere of Aksaray, Turkey. The primary purpose of this study was to investigate size distribution, temporal variation, and related health risks of PAHs. During the winter season, concentrations of PAHs in the sampling site were almost ten times higher than in summer, and approximately 85% of the PAHs belonged to the fine PM fraction. On the other hand, it was determined that the emission sources of the detected PAHs in the summer season were traffic-related emissions. The smallest particle size range (0.45–0.63 μm) consisted of the maximum PAH concentration (1.22±0.05 ng m⁻³) about other particle sizes during the summer season. Fluoranthene (Flt) was the main PAH species determined during winter, indicating that coal combustion is a dominant pollution source. The size distribution properties of PAHs showed similar characteristics for coarse particles, which was also the case for fine particles. In addition, as the ring number of PAHs increases, the height of the peaks decreases in the size distribution plots of coarse particles. Higher molecular weight (HMW) PAHs show higher carcinogenicity potential, mainly found in the fine PM fraction. A health risk assessment was estimated by toxicity equivalent quantity (TEQ) and inhalation cancer risk (ICR), indicating medium risk for the fine PMs and low risk for the coarse PMs.

Due to a paucity of human movement data, the traditional method for estimating pollution exposure is static: Exposure is based on place of residence. However, local air quality varies over both time and space. This study explores exposure measurement errors associated with ignoring human mobility and its impact on exposure-health effect estimates. Using a random forest classification model, this study examines the impact of a variety of factors on potential measurement errors in personal exposure to outdoor PM_2.5. Mobility data at the individual level was combined with hourly PM_2.5 surfaces at the neighborhood level to estimate and compare residence-based and mobility-based exposures for 100,784 Los Angeles County residents. The results show that exposure measurement errors increase for individuals with high mobility levels. Significant sociodemographic disparities are observed across different exposure classification groups. Exposures of low-income people who have high mobility and reside in polluted neighborhoods tend to be overestimated. In contrast, exposures of high-income people living in neighborhoods with cleaner air are likely to be underestimated. The result on the exposure-health effect suggests that health risks of the socially disadvantaged after exposure to PM_2.5 is likely to be underestimated due to the exposure measurement error introduced by ignoring human mobility.

The rather complex terrain in Austria requires that wind fields with sub-kilometer resolutions have to be generated prior to any kind of dispersion modeling due to the large demand on computation times required by non-hydrostatic prognostic mesoscale models. Proper modeling of highly resolved flows in Alpine regions is still a matter of research, and no harmonized methodology is available at the moment. In order to harmonize the meteorological input for dispersion modeling at the regional level, authorities in Austria aim at providing so-called wind-field libraries for a certain reference year for all stakeholders involved in air quality assessments for regulatory purposes. The region of Styria was the first to establish such a library using the prognostic, non-hydrostatic mesoscale model GRAMM with a horizontal resolution of 300 m in 2015. Over the years, attempts have been made for improving the quality of the wind fields. One of the most challenging issues is the interaction between synoptic-scale flows and local thermally driven winds. In this work, the newly developed mesoscale model GRAMM-SCI is presented, which is driven by ERA5 reanalysis data. Especially, novel nudging techniques allow for nesting and dynamic downscaling wind fields with a horizontal resolution of 100–200 m. Moreover, a methodology called “match-to-observation” (MTO) is presented, which greatly improves the final quality of wind fields. For the first time, a wind-field library for the reference year 2017 has been generated for Styria with this new approach.

The study of persistent organic pollutants (POPs) in different environments has helped to understand the behavior and distribution of these pollutants worldwide. Many developed and developing countries have extensive data on the presence of these pollutants, especially in ambient air and soil. However, the simultaneous measurement of air and soil is less frequent, despite offering the opportunity to characterize air-soil exchange. Moreover, such measurements in upper-middle-income countries such as Turkey are very limited and null in Peru. Both countries also offer unique opportunities to characterize the air-soil exchange since Peru has a semi-arid subtropical desert climate and Turkey has a Mediterranean climate. Therefore, the aim of this study is to determine the simultaneous POP concentrations (polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs)) in ambient air and soil in Turkey and Peru and to reveal the POP exchange between air and soil and flux amounts in the gas phase. POP concentrations in ambient air were measured higher at sampling points in Turkey, while POPs in soil were measured similarly in both countries. Also, the air-soil fugacity fractions indicated net volatilization for low molecular weight PAH and PCB congeners, but net deposition for high molecular weight congeners; equilibrium states were found for medium molecular weight congeners. Fugacity fractions did not change with their molecular weights for OCPs. It has been determined that soil acts as a “secondary source” for low molecular weight PAH and PBC congeners in the atmosphere, while the atmosphere acts as a “sink” for high molecular weight PAH and PCB congeners in the soil. Finally, cancer risk calculations for adults and children have been made, both via inhalation of atmospheric POPs and uptake of POPs from the soil. According to the calculations, no health risks were found for both air and soil for adults and children.