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Higher air temperature and increased ambient ozone (O₃) concentration have been associated with childhood rhinitis risk. However, the potential mediating role of elevated O₃ in the increased childhood rhinitis risk due to higher air temperature exposure has not been examined. This large-scale cross-sectional study included 40,103 preschool children from 7 Chinese capital cities. Information on ever-rhinitis, current-rhinitis, and doctor-diagnosed allergic rhinitis (AR) was collected using a standardized questionnaire. Average air temperature (TEMavg) and O₃ concentration in the whole year, warm season, and cold season were estimated at 1 km spatial resolution. The findings revealed that exposure to higher air temperature (annual TEMavg, warm season TEMavg, and cold season TEMavg) and ambient O₃ (annual O₃, and warm season O₃) were associated with an elevated risk of ever-rhinitis, current-rhinitis, and doctor-diagnosed AR. Moreover, elevated O₃ concentration played important mediation effects on the relationships between higher air temperature and childhood rhinitis risk, with the mediated proportions ranging from 19.92% to 35.14% for the whole year, 18.62% to 32.82% for the warm season, and 3.85% to 13.32% for the cold season. Our study highlighted that controlling O₃ pollution may be an effective approach to mitigate the increasing childhood rhinitis risk due to global warming.

There is currently a paucity of research on the effects of early life exposure to particulate matter (PM) of various size fractions on pneumonia in preschool-aged children. We explored the connections between antenatal and postnatal exposure to atmospheric pollutants and diagnosed pneumonia among 4814 offspring children in Taiyuan City, northern China. Outdoor air pollutant concentrations and ambient temperature were collected. A machine learning-based model was utilized to compute daily mean concentrations of PM10, PM2.5, and PM1 at the home address. Associations were calculated using generalized linear mixed models, and stratified analysis was used to detect sensitive subpopulations. We observed significant associations between prenatal exposure to atmospheric pollutants and the incidence of pneumonia in children. For every 10 mu g/m3 increase, the odds ratios (ORs) were 1.06 for PM10, 1.15 for PM2.5, 1.24 for PM1, and 1.05 for SO2 for the whole pregnancy period. In midpregnancy, the most vital connections were found for PM10, PM2.5, and PM1 exposure. Girls showed higher sensitivity to exposure to PM2.5 and PM10. The most significant connections between PM and pneumonia were observed at high SO2 exposure. Connections between PM1, PM2.5 and pneumonia were stronger in children without environmental tobacco smoke (ETS) at home. Associations between PM10 and pneumonia were stronger in children with ETS at home. The synthesis of the data suggests that exposure to PM10, PM2.5, PM1, and SO2 during pregnancy contributes to an elevated susceptibility to childhood pneumonia. The second trimester period is significant and represents a critical window of vulnerability. PM1 may have the strongest impact. Exposure to SO2 can further enhance the PM related risks of pneumonia. Gender and ETS exposure at home can modify associations between outdoor PM and pneumonia. Further reductions in outdoor PM, especially PM1, are needed to reduce childhood pneumonia in China.

The adverse health effects of indoor PM_2.5 are considerably influenced by its elemental composition. Here, we evaluated indoor PM_2.5 elements in preschools in Taiyuan, China, and assessed the lifetime carcinogenic and non-carcinogenic risks of 11 selected elements in children. Additionally, we assessed the association between these elements and fractional exhaled nitric oxide (FeNO), a non-invasive biomarker of respiratory symptoms. We randomly selected 10 preschools in Taiyuan and measured FeNO levels in 507 5-year-old children. Elemental analysis of the PM_2.5 samples was conducted using inductively coupled plasma-mass spectrometry. Associations between PM_2.5-bound elements and FeNO were calculated using linear mixed models. Health risk assessments revealed that Cr and Mn have hazard quotient > 1, indicating they pose a non-carcinogenic risk in the study area. Meanwhile, Cr, Ni, As, Cd, and Co presented carcinogenic health risks with R_i > 10⁻⁶. The risks of other toxic heavy metals were within acceptable limits. The indoor levels of most elements in PM_2.5 correlated with elevated FeNO levels. This study provides novel insights into the associations between PM_2.5-bound elements in classrooms and FeNO among children. It is crucial to implement strategies controlling heavy-metal pollution in preschools and ensuring the protection of children who may be exposed.

Rhinitis is one of the most common respiratory diseases, influenced by various environmental factors such as green space, air pollution and indoor microbiomes. However, their interactions and combined effects have not been reported. We recruited 1121 preschool children from day care centers in a northern city of China. Health and demographic data were collected through questionnaires answered by the children's parents. Surrounding green space was assessed by Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and land cover data of grassland proportion within 1500/3000 m. Ambient air pollution was estimated using the inverse distance weighted (IDW), and the indoor microbiome in classroom vacuum dust was profiled by bacterial 16S rRNA and fungal ITS amplicon sequencing. Mixed-effect logistic regression revealed the proportion of natural grassland, grassland leaf-off and total grassland was negatively associated with current rhinitis. Stratified analysis indicated that greater green space exposure was associated with a reduced current rhinitis in children at high levels of air pollution. Additionally, grassland also protects children against environmental tobacco smoke at home. Indoor microbiome analysis showed Haemophilus and Dolosigranulum were enriched in low-rhinitis day care centers, while Amaricoccus, Blautia and Mycosphaerella were enriched in high-rhinitis day care centers. Mediation analysis indicated that the indoor microbiome did not have significant mediating effects on the relationship between green space and children's current rhinitis. This is the first study to reveal interactions of green space, air pollution and indoor microbiome on rhinitis, providing new insights into how environmental factors collectively influence respiratory health in children.

Exposure to higher surface air temperatures (SAT) and indoor dampness-mold can be associated with increased childhood asthma risk. However, the combined effect of heat and humidity on asthma risk, and the relationship between humid-heat and indoor dampness-mold remain unexplored. Based on a multi-city study of 37,206 Chinese preschool children, we investigated the relationships of exposure to humid-heat (SAT, heat index (HI), humidex (HMI), wet-bulb temperature (WBT)), indoor dampness-mold (dampness-mold in dwelling (DMD), and dampness-mold in clothing and bedding (DMCB)) during infancy with asthma risk. For each 1 °C increase in SAT, HI, HMI, and WBT, the odds ratio (OR) for asthma was 1.104 (95 %CI: 1.078, 1.131), 1.078 (95 %CI: 1.058, 1.099), 1.062 (95 %CI: 1.047, 1.078), and 1.085 (95 %CI: 1.063, 1.107), respectively. Exposure-response analysis showed nearly linear increasing relationships. Higher SAT, HI, HMI, and WBT were significantly associated with increased DMD and DMCB risk. Compared with those with neither DMD nor DMCB, the OR for asthma was 1.663 (95 %CI: 1.423, 1.935) among children with either DMD or DMCB, and 2.223 (95 %CI: 1.788, 2.735) among children with both DMD and DMCB. Our study highlights the importance of reducing humid-heat and indoor dampness-mold exposure during infancy to mitigate the high prevalence of childhood asthma.

Students spend most of their daytime in classrooms to perform academic activities. The indoor climate, PM2.5 levels and ventilation rates in these classrooms are essential to students' health and learning efficiency. The present study aimed to investigate the indoor climate, PM2.5 levels and ventilation rates in Chinese elementary school classrooms. Investigations and measurements were conducted in 47 classrooms across 10 elementary schools in the Tianjin area of China. We continuously monitored air temperature, relative humidity, PM2.5 concentration, CO2 concentration and ventilation rate from January 2019 to June 2021. The study also included short-term measurements of formaldehyde, total volatile organic compounds (TVOCs), and ultrafine particles during different seasons. Key findings indicate that the median ventilation rate was below the Chinese standard requirement in most classrooms. Following the outbreak of the COVID-19 pandemic, an increase in ventilation rates was observed. Further analysis revealed that changes in temperature cannot fully account for these variations. The increase may be related to heightened ventilation awareness. The median CO2 ranged from 1043 to 2237 ppm, emphasizing the need for improved ventilation. The concentrations of the air pollutants (TVOC, formaldehyde, PM2.5) in all classrooms were generally below their respective guideline values. The median ultrafine particle concentration ranged from 5297 to 9148 particles/cm3. The study also highlighted the impact of seasonal variations on indoor air quality, with winter months presenting higher pollutant levels due to limited ventilation.

Background/Objectives:

The integration of microbiome and metabolome data could unveil profound insights into biological processes. However, widely used multi-omic data analyses often employ a stepwise mining approach, failing to harness the full potential of multi-omic datasets and leading to reduced detection accuracy. Synergistic analysis incorporating microbiome/metabolome data are essential for deeper understanding.

Method:

This study introduces a Coupled Matrix and Tensor Factorization (CMTF) framework for the joint analysis of microbiome and metabolome data, overcoming these limitations. Two CMTF frameworks were developed to factorize microbial taxa, functional pathways, and metabolites into latent factors, facilitating dimension reduction and biomarker identification. Validation was conducted using three diverse microbiome/metabolome datasets, including built environments and human gut samples from inflammatory bowel disease (IBD) and COVID-19 studies.

Results:

Our results revealed biologically meaningful biomarkers, such as Bacteroides vulgatus and acylcarnitines associated with IBD and pyroglutamic acid and p-cresol associated with COVID-19 outcomes, which provide new avenues for research. The CMTF framework consistently outperformed traditional methods in both dimension reduction and biomarker detection, offering a robust tool for uncovering biologically relevant insights.

Conclusions:

Despite its stringent data requirements, including the reliance on stratified microbial-based pathway abundances and taxa-level contributions, this approach provides a significant step forward in multi-omics integration and analysis, with potential applications across biomedical, environmental, and agricultural research.

House dust mite (HDM) allergen is a risk factor for children's health. There are few studies of associations of house dust mites with childhood asthma, wheeze, rhinitis and eczema in northern China. During 2013-2016, we performed a nested case-control study involving 410 children from 399 homes. The concentration of Dermato-phagoides farina class I allergen (Der f 1) was measured in dust samples from mattresses in children's bedroom by enzyme-linked immunosorbent assay (ELISA). The indoor environmental parameters such as pets keeping and environmental tobacco smoke (ETS) were collected by a questionnaire. Adjusted odds ratios (AOR) of Der f 1 to children's allergic symptoms was estimated by logistic regression. A non-linear trend was found on the associ-ation between asthma and HDM exposure, and the risk of wheezing rose at low levels of Der f 1 exposure and the risk attenuated thereafter. A dose-response trend with the prevalence of rhinitis and eczema among children was observed with the increase of concentration of house dust mite allergen Der f 1 in bed mattress. When con-centration of Der f 1 was above 4500 ng/g, the adjusted odds ratios of rhinitis current (AOR = 2.40), eczema ever (AOR = 12.23), eczema current (AOR = 2.52) and diagnosed eczema (AOR = 6.41) reached significance (p < 0.05).

The available information on endotoxin in Chinese households is limited and there is inconsistency regarding its impact on asthma and allergies in children. A case-control study was performed in 324 homes in Tianjin, China. Linear regression analysis was performed to identify the determinants of endotoxin concentrations in household dust. Logistic regression models were employed to investigate the associations of endotoxin concentrations with asthma and allergies in children. Endotoxin concentrations were determined from 284 valid dust samples, ranging from 94 to 11,625 EU/g, with a mean concentration of 3638 EU/g. We found a significant positive association between endotoxin concentrations and children's current asthma. Old houses, ventilation systems without exhaust fans and windows opened infrequently were related to higher concentrations of endotoxins. In conclusion, endotoxin exposure in the home might be a risk factor for current asthma in children. Strategies for controlling endotoxin concentrations such as building maintenance and ventilation improvements are recommended.

Objective: To study associations between fractional exhaled nitric oxide (FeNO) and asthma, airway symptoms, sensitization to common allergens, outdoor pollution and home environment among 380 students in eight junior high schools in two areas in Indonesia.

Methods: Data on health and home were collected by a face-to face interview before measuring FeNO and performing skin prick test against common allergens. Exploratory linear mixed and logistic regression models were employed.

Results: Geometric mean of FeNO was 17.8 ppb (GSD 2.09) and 139 students (36.6%) had elevated FeNO (>20 ppb). In total, 107 students (28.2%) were sensitized to house dust mite (HDM) (Der p1 or Der f1), 4 (1.1%) to cat and 3 (0.8%) to mold (Cladosporium or Alternaria). Moreover, 20 students (5.3%) had diagnosed asthma, 38 (10.0%) had current wheeze, and 107 (28.2%) had current rhinitis. HDM sensitization, diagnosed asthma, current wheeze, and current rhinitis were associated with FeNO. In total, 281 students (73.9%) had mold or dampness, 232 (61.1%) had environmental tobacco smoke (ETS) and 43 (11.3%) had other odor at home. Indoor mold or dampness and other odor at home were associated with FeNO. ETS was negatively associated with FeNO.

Conclusion: HDM sensitization and elevated FeNO can be common among children in this part of Indonesia. The high prevalence of elevated FeNO indicate that undiagnosed childhood asthma is common. Dampness, mold and odor at home can be associated with increased FeNO while ETS can be associated with decreased FeNO.