Maternal exposure to PM2.5/BC during pregnancy predisposes children to allergic rhinitis which varies by regions and exclusive breastfeeding

Exposure to Anthropogenic Heat Was Associated with the Increased Risks of Respiratory Allergy Symptoms in Preschool Children: A New Insight into the Urban Heat Island Effect

Anthropogenic heat (AH) exerts a substantial influence on the local urban climate and intensifies the urban heat island (UHI) effect. However, the impact of AH exposure on respiratory allergy symptoms in preschool children has not been investigated. This study conducted a cross-sectional study of 39088 Chinese preschool children to investigate the associations between multisource AH exposure (building heat, industrial heat, metabolic heat, transportation heat, and total heat) and the risks of respiratory allergy symptoms (wheezing, night-cough, and rhinitis). Exposure to higher levels of AH was associated with increased risks of wheezing (building heat, transportation heat, and total heat), night-cough (building heat), and rhinitis (building heat, metabolic heat, transportation heat, and total heat) symptoms. Exposure-response relationships demonstrated positive relationships between AH with wheezing, night-cough, and rhinitis symptoms, with nearly linear and inverted "J" shapes. Building heat contributed most to the impact of multisource AH on wheezing, night-cough, and rhinitis symptoms, with weighted quantile sum weights ranging from 0.513 to 0.887. Our study provided new epidemiological insights into the impact of the UHI effect on childhood respiratory allergies and highlighted that mitigating AH exposure, specifically from building heat, could be an effective strategy for reducing the disease burden of respiratory allergies in children.

Association of multiple environmental exposures with rhinitis and asthma symptoms in preschool children: Identifying critical risk factor

BACKGROUND

The concept "one airway, one disease" for childhood rhinitis and asthma has been challenged in recent years. This study aimed to evaluate associations of environmental exposures with alone and co-morbid symptoms of rhinitis and asthma and identify critical risk factor.

METHODS

5828 children aged 3-6 years in Shanghai were surveyed in 2019. Rhinitis and wheezing symptoms in the past 12 months were collected using questionnaire. 11 outdoor environment exposure factors were assessed by high-resolution spatial-temporal model based on residences. Logistic regression and random forest were applied to evaluate and rank the association of environmental exposure with rhinitis and wheezing symptoms.

RESULTS

The proportions of children with rhinitis alone, wheezing & rhinitis, and wheezing alone were 37.2 %, 4.6 %, and 2.6 %, respectively. Regression modeling of two exposure factors adjusted for each other showed that PM1, PM2.5 and nighttime light(NTL) remained the robust significant associations with rhinitis alone, whereas NO2 had the robust significant association with wheezing & rhinitis and wheezing alone. Random forest ranking analysis further corroborated the most significant environmental exposure for rhinitis alone was PM1, and for wheezing symptoms (both wheezing & rhinitis and wheezing alone) was NO2. Significant additive and multiplicative interactions were examined between indoor dampness and PM1 exposure on rhinitis alone.

CONCLUSION

Children's current rhinitis alone was more susceptible to ambient PM1 and PM2.5, while asthmatic wheezing symptom, either with or without rhinitis, was more susceptible to NO2. Co-exposure to indoor dampness and PM1 exposure had synergistic effects on rhinitis alone.

Prenatal and postnatal early life exposure to greenness and particulate matter of different size fractions in relation to childhood rhinitis - A multi-center study in China

The impact of early life exposure to residential greenness on childhood rhinitis and its interaction with particulate matter (PM) of different size fractions remain inconsistent. Herein, we recruited 40,486 preschool children from randomly selected daycare centers in 7 cities in China from 2019 to 2020, and estimated exposure to residential greenness by the normalized difference vegetation index (NDVI) with a 500 m buffer. Exposure to ambient PM (PM1, PM2.5, and PM10) was evaluated using a satellite-based prediction model (daily, at a resolution of 1 km × 1 km). By mixed-effect logistic regression, NDVI values during pregnancy, in the first (0-1 year old) and the second (1-2 years old) year of life were negatively associated with lifetime rhinitis (LR) and current rhinitis (CR) (P < 0.001). PM in the same time windows was associated with increased risks of LR and CR in children, with smaller size fraction of PM showing greater associations. The negative associations between prenatal and postnatal NDVI and LR and CR in preschool children remained robust after adjusting for concomitant exposure to PM, whereas the associations of postnatal NDVI and rhinitis showed significant interactions with PM. At lower levels of PM, postnatal NDVI remained negatively associated with rhinitis and was partly mediated by PM (10.0-40.9 %), while at higher levels of PM, the negative associations disappeared or even turned positive. The cut-off levels of PM were identified for each size fraction of PM. In conclusion, prenatal exposure to greenness had robust impacts in lowering the risk of childhood rhinitis, while postnatal exposure to greenness depended on the co-exposure levels to PM. This study revealed the complex interplay of greenness and PM on rhinitis in children. The exposure time window in prenatal or postnatal period and postnatal concomitant PM levels played important roles in influencing the associations between greenness, PM and rhinitis.

An Inflammatory Question? Prenatal Air Pollution, Childhood Allergic Rhinitis, and Healthy Fats

A study of more than 650 toddlers found that two polyunsaturated fatty acids were associated with fewer cases of allergic rhinitis (hay fever) in children who had been exposed prenatally to higher levels of PM2.5.

Greenness and its composition and configuration in association with allergic rhinitis in preschool children

BACKGROUND

Few studies focus on the associations of green space composition and configuration with children's allergic rhinitis (AR).

METHODS

A multi-center population-based cross-sectional study was performed in 7 cities in mainland of China between 2019 and 2020, recruiting 36,867 preschool children. Information on the current AR symptoms and demographics were collected by questionnaire. Exposure to residential greenness was estimated by Normalized Difference Vegetation Index (NDVI, 1000 m buffer) around the residences. Greenness composition was estimated in 3 main categories: forest, grassland, shrubland. Configuration of each category and total greenness (a spatial resolution of 10 m × 10 m) was estimated by 6 landscape pattern metrics to quantify their area, shape complexity, aggregation, connectivity, and patch density. Exposure to daily ambient particulate matter (PM1, PM2.5 and PM10, a spatial resolution of 1 km × 1 km) was estimated. Multilevel logistic regression models were applied to analyze the associations of greenness and its composition and configuration with AR, and mediation effects by PMs were examined by mediation analysis models.

RESULTS

The prevalence of self-reported current AR in preschool children was 33.1%. Two indicators of forest, Aggregation Index of forest patches (AIforest) (odds ratio (OR):0.92, 95% Confidential Interval (CI): 0.88-0.97), and Patch Cohesion of forest (COHESIONforest) (OR: 0.93, 95% CI:0.89-0.98) showed significantly negative associations with AR symptoms. Mediation analyses found the associations were partially mediated by PMs. Age, exclusive breastfeed duration and season were the potential effect modifiers. The associations varied across seven cities.

CONCLUSION

Our findings suggest the inverse associations of the aggregation and connectivity of forest patches surrounding residence addresses with AR symptoms. Since the cross-sectional study only provides associations rather than causation, further studies are needed to confirm our results as well as the underlying mechanisms.

Improved ambient air quality is associated with decreased prevalence of childhood asthma and infancy shortly after weaning is a sensitive exposure window

BACKGROUND

The urban ambient air quality has been largely improved in the past decade. It is unknown whether childhood asthma prevalence is still increasing in ever top-ranking city of Shanghai, whether the improved air quality is beneficial for children's asthma and what time window of exposure plays critical roles.

METHODS

Using a repeat cross-sectional design, we analyzed the association between early life exposure to particles and wheezing/asthma in each individual and combined surveys in 2011 and 2019, respectively, in 11,825 preschool children in Shanghai.

RESULTS

A significantly lower prevalence of doctor-diagnosed asthma (DDA) (6.6% vs. 10.5%, p < 0.001) and wheezing (10.5% vs. 23.2%, p < 0.001) was observed in 2019 compared to 2011. Exposure to fine particulate matter (PM2.5), coarse particles (PM2.5-10) and inhalable particles (PM10) was decreased in 2019 by 6.3%, 35.4%, and 44.7% in uterus and 24.3%, 20.2%, and 31.8% in infancy, respectively. Multilevel log-binomial regression analysis showed exposure in infancy had independent association with wheezing/DDA adjusting for exposure in uterus. For each interquartile range (IQR) increase of infancy PM2.5, PM2.5-10 and PM10 exposure, the odds ratios were 1.39 (95% confidence interval (CI): 1.24-1.56), 1.51 (95% CI:1.15-1.98) and 1.53 (95% CI:1.27-1.85) for DDA, respectively. The distributed lag non-linear model showed the sensitive exposure window (SEW) was 5.5-11 months after birth. Stratified analysis showed the SEWs were at or shortly after weaning, but only in those with <6 months of exclusive breastfeeding.

CONCLUSIONS

Improved ambient PM benefits in decreasing childhood asthma prevalence. We firstly reported the finding of SEW to PM at or closely after weaning on childhood asthma.

The Associations of Prenatal Exposure to Fine Particulate Matter and Its Chemical Components with Allergic Rhinitis in Children and the Modification Effect of Polyunsaturated Fatty Acids: A Birth Cohort Study

BACKGROUND

Polyunsaturated fatty acids (PUFAs) have been shown to protect against fine particulate matter < 2.5 μ m in aerodynamic diameter (PM 2.5 )-induced hazards. However, limited evidence is available for respiratory health, particularly in pregnant women and their offspring.

OBJECTIVES

We aimed to investigate the association of prenatal exposure to PM 2.5 and its chemical components with allergic rhinitis (AR) in children and explore effect modification by maternal erythrocyte PUFAs.

METHODS

This prospective birth cohort study involved 657 mother-child pairs from Guangzhou, China. Prenatal exposure to residential PM 2.5 mass and its components [black carbon (BC), organic matter (OM), sulfate (SO 4 2 - ), nitrate (NO 3 - ), and ammonium (NH 4 + )] were estimated by an established spatiotemporal model. Maternal erythrocyte PUFAs during pregnancy were measured using gas chromatography. The diagnosis of AR and report of AR symptoms in children were assessed up to 2 years of age. We used Cox regression with the quantile-based g-computation approach to assess the individual and joint effects of PM 2.5 components and examine the modification effects of maternal PUFA levels.

RESULTS

Approximately 5.33 % and 8.07% of children had AR and related symptoms, respectively. The average concentration of prenatal PM 2.5 was 35.50 ± 5.31   μ g / m 3 . PM 2.5 was positively associated with the risk of developing AR [hazard ratio ( HR ) = 1.85 ; 95% confidence interval (CI): 1.16, 2.96 per 5   μ g / m 3 ] and its symptoms (HR = 1.79 ; 95% CI: 1.22, 2.62 per 5   μ g / m 3 ) after adjustment for confounders. Similar associations were observed between individual PM 2.5 components and AR outcomes. Each quintile change in a mixture of components was associated with an adjusted HR of 3.73 (95% CI: 1.80, 7.73) and 2.69 (95% CI: 1.55, 4.67) for AR and AR symptoms, with BC accounting for the largest contribution. Higher levels of n-3 docosapentaenoic acid and lower levels of n-6 linoleic acid showed alleviating effects on AR symptoms risk associated with exposure to PM 2.5 and its components.

CONCLUSION

Prenatal exposure to PM 2.5 and its chemical components, particularly BC, was associated with AR/symptoms in early childhood. We highlight that PUFA biomarkers could modify the adverse effects of PM 2.5 on respiratory allergy. https://doi.org/10.1289/EHP13524.

Prenatal Exposure to Air Pollutants Associated with Allergic Diseases in Children: Which Pollutant, When Exposure, and What Disease? A Systematic Review and Meta-analysis

This systematic review aims to identify the association between prenatal exposure to air pollutants and allergic diseases in children, focusing on specific pollutants, timing of exposure, and associated diseases. We searched PubMed, Scopus, and Web of Science for English articles until May 1, 2023, examining maternal exposure to outdoor air pollutants (PM1, PM2.5, PM10, NO, NO2, SO2, CO, and O3) during pregnancy and child allergic diseases (atopic dermatitis (AD), food allergy (FA), asthma (AT) and allergic rhinitis (AR)/hay fever (HF)). The final 38 eligible studies were included in the meta-analysis. Exposure to PM2.5 and NO2 during pregnancy was associated with the risk of childhood AD, with pooled ORs of 1.34 (95% confidence interval (CI), 1.10-1.63) and 1.10 (95%CI, 1.05-1.15) per 10 µg/m3 increase, respectively. Maternal exposure to PM1, PM2.5, and NO2 with a 10 µg/m3 increase posed a risk for AT, with pooled ORs of 1.34 (95%CI, 1.17-1.54), 1.11 (95%CI, 1.05-1.18), and 1.07 (95%CI, 1.02-1.12), respectively. An increased risk of HF was observed for PM2.5 and NO2 with a 10 µg/m3 increase, with ORs of 1.36 (95%CI, 1.17-1.58) and 1.26 (95%CI, 1.08-1.48), respectively. Traffic-related air pollutants (TRAP), particularly PM2.5 and NO2, throughout pregnancy, pose a pervasive risk for childhood allergies. Different pollutants may induce diverse allergic diseases in children across varying perinatal periods. AT is more likely to be induced by outdoor air pollutants as a health outcome. More research is needed to explore links between air pollution and airway-derived food allergies.

Association of urinary nickel levels with diabetes and fasting blood glucose levels: A nationwide Chinese population-based study

Some epidemiological studies support a relationship between nickel exposure and diabetes in the general population. To address this, we tested the association of nickel exposure with diabetes in 10,890 adults aged ≥ 18 years old from the China National Human Biomonitoring study conducted in 2017-2018. Urinary nickel concentrations and fasting blood glucose (FBG) were measured, and lifestyle and demographic data were collected. Weighted logistic and linear regressions were used to estimate the associations of urinary nickel levels with diabetes prevalence and FBG. Restricted cubic splines (RCS) were used to test for the dose-response relationship. The odd ratio (95% confidence interval [CI]) of diabetes for the highest versus lowest quartiles of urinary nickel concentrations was 1.74 (1.28, 2.36) in the multivariate model (p _trend =0.001). Each one-unit increase in log-transformed urinary nickel concentrations was associated with a 0.36 (0.17, 0.55) mmol/L elevation in FBG. The RCS curves showed a monotonically increasing dose-response relationship of urinary nickel with diabetes as well as FBG levels, and then tended to flatten after about 4.75 μg/L of nickel exposure. The nickel-diabetes association was stronger in individuals with lower than those with higher rice consumption (OR: 2.39 vs. 1.72). Our study supports a positive association between nickel exposure and diabetes prevalence in Chinese adults, especially in individuals with lower rice consumption. Further large-scale prospective studies are needed to validate our findings.

Adverse Effects of Black Carbon (BC) Exposure during Pregnancy on Maternal and Fetal Health: A Contemporary Review

Black carbon (BC) is a major component of ambient particulate matter (PM), one of the six Environmental Protection Agency (EPA) Criteria air pollutants. The majority of research on the adverse effects of BC exposure so far has been focused on respiratory and cardiovascular systems in children. Few studies have also explored whether prenatal BC exposure affects the fetus, the placenta and/or the course of pregnancy itself. Thus, this contemporary review seeks to elucidate state-of-the-art research on this understudied topic. Epidemiological studies have shown a correlation between BC and a variety of adverse effects on fetal health, including low birth weight for gestational age and increased risk of preterm birth, as well as cardiometabolic and respiratory system complications following maternal exposure during pregnancy. There is epidemiological evidence suggesting that BC exposure increases the risk of gestational diabetes mellitus, as well as other maternal health issues, such as pregnancy loss, all of which need to be more thoroughly investigated. Adverse placental effects from BC exposure include inflammatory responses, interference with placental iodine uptake, and expression of DNA repair and tumor suppressor genes. Taking into account the differences in BC exposure around the world, as well as interracial disparities and the need to better understand the underlying mechanisms of the health effects associated with prenatal exposure, toxicological research examining the effects of early life exposure to BC is needed.