Indoor air最新文献

Indoor environments affect occupant hygiene, comfort, and productivity. Special treatments, such as spraying essential oils, disinfectant gases, and water vapor or droplets, have been proposed to improve indoor comfort in recent years. Therefore, a method to control the concentrations of these beneficial substances is required. To control the indoor concentration distribution of various degradable substances emitted indoors, this article proposes a novel method that uses the linear relationship between the source and concentration distributions. The method was evaluated through numerical experiments using CFD. Furthermore, the effects of the deposition (Dep) and decomposition (Dec) of the substances on the performance were assessed. The method successfully determined the optimal emission intensities for each emission source to make the concentration field close to the objective—the uniform distribution—in the experiment. When substances decomposed in the air or were deposited on the walls, the performance of the optimal control decreased compared to the case without Dec or Dep. This indicated that the occurrence of Dec or Dep lowered the optimization performance by enhancing the unevenness of the concentration field in the area near the emission source and far from the source. The Dep case showed relatively lower performance than the Dec case because the Dep occurred more spatially unevenly than the Dec. In addition, the more emission sources employed, the smaller the gap between the objective and the optimized concentration field. This method will help control indoor air quality more efficiently.

Background: Little is known about how exposure to different types of pollution is associated with motor development in children or how pollution may be related to time spent in physical activity, sedentary behaviour—including screen time, and sleep. The purpose of this study was to review the evidence on these associations, especially in light of the World Health Organization (WHO) Guidelines for these behaviours.

Methods: We searched eight electronic databases: CINAHL, Embase, ERIC, Global Health, MEDLINE, PsycINFO, Scopus, and Web of Science, from inception to May 2023. Studies that reported an association between a pollution measure (air, water, noise, or land) and at least one movement behaviour (physical activity, sleep, or sedentary time) or motor development outcome (fine or gross motor) among apparently healthy children from birth to 12 years were included. Eligibility of the studies was assessed, and extracted data was based on the study design, sample characteristics, pollution type, and type of association reported.

Results: The search returned 5358 studies, of which 18 were eligible for inclusion. Most studies were conducted in high-income countries (n = 13). Studies reported measures of outdoor air (n = 7), indoor air (n = 4), land (n = 3), and noise pollution (n = 4). Findings from the review were mixed and inconsistent. Most studies reported associations between a pollution measure and motor development outcomes (n = 12), followed by sleep (n = 5) and physical activity and sedentary behaviour (n = 1).

Conclusions: There is limited evidence regarding associations between pollution measures, 24-h movement behaviours, and motor development. Future research should pay more attention to postnatal exposure to different types of pollution and its impact on healthy levels of physical activity, sedentary behaviour, sleep, and motor development and consider confounders such as geographic location, weather conditions, and country income level.

Trial Registration: PROSPERO: CRD42022340130.

A method was developed to analytically distinguish between the ventilated (v) and nonventilated (nv) fractions of water-soluble ions in deposits of particle indoors. The indicative method was based on low-cost passive outdoor and indoor sampling of the particle and ion deposits and NO₂ gas and analysis of the regression values and residuals of the correlations between these parameters. The method was applied to measurements in the Pieskowa Skała Castle Museum in Poland. A dominating source of “soil and building dust” was indicated all year round, probably partly from renovation works of the castle, with larger total infiltration in the winter–spring (W-S) but with a higher proportion of ventilation ingress in the summer–autumn (S-A). About 60%–80%, by mass, of the water-soluble ions in the soil and building dust were calcium and probably some magnesium bicarbonate (Ca(HCO₃)₂, Mg(HCO₃)₂) and about 10%–20% sulfates (SO₄⁻⁻) with calcium (Ca⁺⁺) and several other cations. The other main source of the ion deposits was indicated to be air pollution, with chloride (Cl⁻), sulfate (SO₄⁻⁻), and nitrate (NO₃⁻), from outdoor combustion sources, like traffic, residential heating, and industry. These were mainly v from outdoors in the colder parts of the year, but also to the more open locations in the S-A. A small source of nv sulfate (SO₄⁻⁻) was identified inside two showcases in the S-A. The study showed good enclosure protection of the museum objects against exposure to particle pollution, but also the need to avoid the trapping of particle pollution inside showcases or closed rooms. The identification of the probable different amounts and sources of v and nv ions in the castle aided preventive actions to reduce the pollution exposure.

Nowadays, dust exposure pollution is receiving a lot of attention due to its significant impact on public health. To investigate the impact of dust particle size and human respiratory strength on respiratory particle deposition patterns, data was collected through on-site surveys. The study analyzed the equivalent respiratory strength, dust environment characteristics, and bronchial particle escape and deposition patterns of humans in fully mechanized mining faces at various operating times. This was done using ergonomic energy consumption simulation experiments and a fluid–solid interaction method of CFD-DEM. The findings revealed that as humans worked continuously for 5, 15, 30, 45, and 60 min, their respiratory intensity corresponded to 8, 18, 30, 42, and 50 L/min, respectively. According to the field investigation and particle size analysis, the particle size distribution of 1~5, 5~10, 10~20, 20~30, and 30~40 μm particles accounted for 36%, 26%, 15%, 11%, and 10%, respectively. In general, the deposition rate of dust was highest in the main bronchus of the respiratory tract, followed by the trachea area. Particles ranging from 5 to 10 μm in size were observed to have a higher likelihood of escaping from the tertiary bronchioles and entering the secondary bronchial regions. Conversely, particles larger than 20 μm exhibited a deposition rate of up to 80% in the tertiary bronchial regions. It was noted that the bronchial deposition rate of particles of varying sizes increased with respiratory strength, with smaller particles showing greater sensitivity to changes in respiratory strength in terms of the deposition fraction. Among the different particle sizes, the deposition rate of 5–10 μm particles exhibited the most variation with increasing respiration intensity, ranging up to 17%.

We use air pollution exposure measurements and household survey data from four studies conducted across three countries in sub-Saharan Africa (SSA) to analyze the association between carbon monoxide (CO) exposure from cooking with biomass and indicators of cognitive impairment. While there is strong evidence on the relationship between ambient air pollution exposure and cognitive impairment from studies in high-income countries, relatively little research has focused on household air pollution (HAP) in low-income country settings where risks of HAP exposure are high. This study is the first to our knowledge to focus on the association between HAP exposure (specifically CO exposure) and cognitive impairment across diverse settings in SSA. We use 24-hour measurements of primary cooks’ exposure to CO across four study sites: urban Zambia (n = 493); urban Malawi (n = 130); rural Malawi (n = 102); and urban Rwanda (n = 2,576). We model the estimated percent carboxyhemoglobin (%COHb) of cooks and map values to a toxicological profile for risk of cognitive impairment. We find that across all study settings, cooks’ average %COHb levels are below levels of daily concern, but that cooks who use charcoal for preparing greater than 40% of meals are more likely to spend additional time at higher levels of risk. For the urban Zambia sample, we compare %COHb and frequency of charcoal use to a series of cognitive test scores and find no consistent relationships between %COHb and cognitive test scores. High levels of daily CO exposure from cooks across SSA highlight the potential for longer-term negative cognitive (and other) health outcomes motivating additional research and efforts to characterize and mitigate risk.