Systematic Review and Meta-Analysis of Human Skin Diseases Due to Particulate Matter

Clinical Study on the Induction of Psoriasis Flare-Ups by PM2.5 Air Pollutants via Immune Barrier Dysfunction

OBJECTIVE

This study explores the clinical correlation between the air pollutant PM2.5 and the induction of psoriasis flare-ups through the disruption of the immune barrier.

METHODS

Air quality data, the average mass concentration of the primary atmospheric pollutant PM2.5, and meteorological data spanning from November 2023 to March 2024 were gathered from 9 air quality monitoring stations situated within our city, courtesy of the local Meteorological Information Center. Psoriasis cases were sourced from our hospital's dermatology department, encompassing patients diagnosed and treated from November 2023 to March 2024 and residing within the city.

RESULTS

From January 2023 to May 2024, aberrant expression of Th1 cells and Th2 cells was observed in psoriasis flare-up patients. Spearman correlation coefficient analysis revealed a positive correlation between PM2.5, PM10, and Th1 cells, and a negative correlation with Th2 cells, exhibiting significant differences (P < .05). Supplemental Figure 1 illustrates an increase in psoriasis flare-ups on the fifth day following a unit increase in PM2.5 concentration, with an excess risk (ER) value of 0.046 [95% confidence interval (CI): 0.137-0.893]. Conversely, after an increase of 1 unit of PM10, there was a decrease on the third and fourth days, followed by increases on the fifth, sixth, and seventh days, with ER values of 0.038 (95% CI: 0.013-0.067), 0.045 (95% CI: 0.019-0.073), 0.051 (95% CI: 0.034-0.078), 0.057 (95% CI: 0.045-0.083), and 0.061 (95% CI: 0.051-0.087), respectively.

CONCLUSION

Air pollutant PM2.5 could potentially exacerbate psoriasis flare-ups by compromising the immune barrier, suggesting a plausible mechanism linked to the onset of this condition.

Epithelial barrier dysfunction and associated diseases in companion animals: Differences and similarities between humans and animals and research needs

Since the 1960s, more than 350,000 new chemicals have been introduced into the lives of humans and domestic animals. Many of them have become part of modern life and some are affecting nature as pollutants. Yet, our comprehension of their potential health risks for both humans and animals remains partial. The "epithelial barrier theory" suggests that genetic predisposition and exposure to diverse factors damaging the epithelial barriers contribute to the emergence of allergic and autoimmune conditions. Impaired epithelial barriers, microbial dysbiosis, and tissue inflammation have been observed in a high number of mucosal inflammatory, autoimmune and neuropsychiatric diseases, many of which showed increased prevalence in the last decades. Pets, especially cats and dogs, share living spaces with humans and are exposed to household cleaners, personal care products, air pollutants, and microplastics. The utilisation of cosmetic products and food additives for pets is on the rise, unfortunately, accompanied by less rigorous safety regulations than those governing human products. In this review, we explore the implications of disruptions in epithelial barriers on the well-being of companion animals, drawing comparisons with humans, and endeavour to elucidate the spectrum of diseases that afflict them. In addition, future research areas with the interconnectedness of human, animal, and environmental well-being are highlighted in line with the "One Health" concept.

Urban environment and children's health: An umbrella review of exposure response functions for health impact assessment

BACKGROUND

Urban settlements have become the main living environment. Understanding the impact of urban exposures on human health has therefore become a growing area of research. Up-to-date knowledge about the influence of urban exposures on pregnant women's and children's health is especially relevant, as they are particularly vulnerable to certain external influences.

AIM

This review aims to provide a synthesis of systematic reviews with meta-analyses reporting on an association between the urban environmental risk factors and health outcomes in pregnancy, infants, children and adolescents.

METHODS

We conducted an umbrella review, methodically analysing systematic reviews with meta-analyses, published between January 2016 and December 2022 in PubMed or Scopus. Adhering to the PRISMA checklist, we searched for free text using Medical Subject Headings (MeSH) terms related to air pollution, noise pollution, temperature, green space exposure, built and food environment, health outcomes, children (aged 0-18 years), pregnancy and systematic reviews with meta-analyses. We extracted key characteristics of each included study and assessed the quality of the included studies via the R-AMSTAR 2 tool.

RESULTS

Twenty-four studies met our inclusion criteria and identified 104 associations including 15 exposures and 60 health outcomes. The most frequently studied associations were related to air pollutants, followed by the built and food environment and noise. Birth outcomes (including low birth weight, pre-term birth or stillbirth) were the most commonly affected health outcomes, followed by respiratory outcomes such as asthma or respiratory infections. A total of 45 exposure-response function were reported to be statistically significant, including 10 exposures and 23 health effects.

CONCLUSION

This umbrella review provides an overview of the evidence and availability of exposure response functions between selected urban exposures and child health outcomes. This helps to identify research gaps and to build the basis for health impact assessment.

Particulate Matter and Its Molecular Effects on Skin: Implications for Various Skin Diseases

Particulate matter (PM) is a harmful air pollutant composed of chemicals and metals which affects human health by penetrating both the respiratory system and skin, causing oxidative stress and inflammation. This review investigates the association between PM and skin disease, focusing on the underlying molecular mechanisms and specific disease pathways involved. Studies have shown that PM exposure is positively associated with skin diseases such as atopic dermatitis, psoriasis, acne, and skin aging. PM-induced oxidative stress damages lipids, proteins, and DNA, impairing cellular functions and triggering inflammatory responses through pathways like aryl hydrocarbon receptor (AhR), NF-κB, and MAPK. This leads to increased production of inflammatory cytokines and exacerbates skin conditions. PM exposure exacerbates AD by triggering inflammation and barrier disruption. It disrupts keratinocyte differentiation and increases pro-inflammatory cytokines in psoriasis. In acne, it increases sebum production and inflammatory biomarkers. It accelerates skin aging by degrading ECM proteins and increasing MMP-1 and COX2. In conclusion, PM compromises skin health by penetrating skin barriers, inducing oxidative stress and inflammation through mechanisms like ROS generation and activation of key pathways, leading to cellular damage, apoptosis, and autophagy. This highlights the need for protective measures and targeted treatments to mitigate PM-induced skin damage.

Beyond surface: Unveiling ecological and economic ramifications of microplastic pollution in the oceans

Every year, the global production of plastic waste reaches a staggering 400 million metric tons (Mt), precipitating adverse consequences for the environment, food safety, and biodiversity as it degrades into microplastics (MPs). The multifaceted nature of MP pollution, coupled with its intricate physiological impacts, underscores the pressing need for comprehensive policies and legislative frameworks. Such measures, alongside advancements in technology, hold promise in averting ecological catastrophe in the oceans. Mandated legislation represents a pivotal step towards restoring oceanic health and securing the well-being of the planet. This work offers an overview of the policy hurdles, legislative initiatives, and prospective strategies for addressing global pollution due to MP. Additionally, this work explores innovative approaches that yield fresh insights into combating plastic pollution across various sectors. Emphasizing the importance of a global plastics treaty, the article underscores its potential to galvanize collaborative efforts in mitigating MP pollution's deleterious effects on marine ecosystems. Successful implementation of such a treaty could revolutionize the plastics economy, steering it towards a circular, less polluting model operating within planetary boundaries. Failure to act decisively risks exacerbating the scourge of MP pollution and its attendant repercussions on both humanity and the environment. Central to this endeavor are the formulation, content, and execution of the treaty itself, which demand careful consideration. While recognizing that a global plastics treaty is not a panacea, it serves as a mechanism for enhancing plastics governance and elevating global ambitions towards achieving zero plastic pollution by 2040. Adopting a life cycle approach to plastic management allows for a nuanced understanding of possible trade-offs between environmental impact and economic growth, guiding the selection of optimal solutions with socio-economic implications in mind. By embracing a comprehensive strategy that integrates legislative measures and technological innovations, we can substantially reduce the influx of marine plastic litter at its sources, safeguarding the oceans for future generations.

Association Between Atopic Dermatitis and Aging: Clinical Observations and Underlying Mechanisms

As one of the most prevalent chronic inflammatory skin diseases, atopic dermatitis (AD) increasingly affects the aging population. Amid the ongoing global aging trend, it's essential to recognize the intricate relationship between AD and aging. This paper reviews existing knowledge, summarizing clinical observations of associations between AD and aging-related diseases in various systems, including endocrine, cardiovascular, and neurological. Additionally, it discusses major theories explaining the correlation, encompassing skin-mucosal barriers, systemic inflammation and stress, genes, signal transduction, and environmental and behavioral factors. The association between AD and aging holds significant importance, both in population and basic perspectives. While further research is warranted, this paper aims to inspire deeper exploration of inflammation/allergy-aging dynamics and the timely management of elderly patients with AD.

Effects and mechanisms of polycyclic aromatic hydrocarbons in inflammatory skin diseases

Polycyclic aromatic hydrocarbons (PAHs) are hydrocarbons characterized by the presence of multiple benzene rings. They are ubiquitously found in the natural environment, especially in environmental pollutants, including atmospheric particulate matter, cigarette smoke, barbecue smoke, among others. PAHs can influence human health through several mechanisms, including the aryl hydrocarbon receptor (AhR) pathway, oxidative stress pathway, and epigenetic pathway. In recent years, the impact of PAHs on inflammatory skin diseases has garnered significant attention, yet many of their underlying mechanisms remain poorly understood. We conducted a comprehensive review of articles focusing on the link between PAHs and several inflammatory skin diseases, including psoriasis, atopic dermatitis, lupus erythematosus, and acne. This review summarizes the effects and mechanisms of PAHs in these diseases and discusses the prospects and potential therapeutic implications of PAHs for inflammatory skin diseases.

Association of air quality index (AQI) with incidence of atopic dermatitis in Taiwan: A nationwide population-based cohort study

BACKGROUND

Air pollutants may aggravate atopic dermatitis (AD). However, the association between Air Quality Index (AQI) and incidence of AD remains unknown.

OBJECTIVE

To investigate association between AQI and incidence of AD, using the nationwide cohort in the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

We included 21,278,938 participants from the NHIRD not diagnosed with AD before 2008. Long-term average AQI value, obtained from the Taiwan Air Quality Monitoring System Network, before AD diagnosis was calculated and linked for each participant.

RESULTS

199,205 incident cases of AD were identified from 2008 to 2018. Participants were classified into 4 quantiles (Q) by AQI value. With the lowest quantile, Q1, as reference, the AD risk increased significantly in the Q2 group (adjusted hazard ratio [aHR]: 1.29, 95% confidence interval [CI]: 1.04-1.65), Q3 group (aHR: 4.71, 95% CI: 3.78-6.04), and was highest in the Q4 group (aHR: 13.20, 95% CI: 10.86-16.60). As AQI treated as a continuous variable, an increase of 1 unit of AQI value added 7% of AD risk (aHR, 1.07, 95% CI: 1.07-1.08).

LIMITATIONS

The NHIRD lacks detailed information on individual subjects.

CONCLUSIONS

The results demonstrated a significant positive association between AQI and incidence of AD with a clear dose-response relationship.

Aryl hydrocarbon receptor role in chronic inflammatory skin diseases: a narrative review

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that has gained increasing attention in the field of dermatology due to its multifaceted role in skin health and disease. This review provides a comprehensive overview of the current state of knowledge regarding the AHR and its implications in dermatological conditions. The AHR is well known for its involvement in xenobiotic metabolism, particularly in response to polycyclic aromatic hydrocarbons and dioxins. However, recent research has unveiled its pivotal role in the skin immune response, barrier function, and homeostasis. The AHR signalling pathway is intricately linked to various dermatological disorders, including psoriasis, atopic dermatitis, acne and hidradenitis suppurativa. In this review, we delve into the molecular mechanisms through which AHR activation influences skin physiology and highlight how dysregulation can lead to pathological conditions. Moreover, we discuss the emerging therapeutic potential of AHR modulators in the treatment of skin diseases. In conclusion, the AHR is a pivotal player in dermatology, with a multifaceted role in skin physiology and pathology. Understanding the intricacies of AHR signalling in the skin offers promising avenues for the development of novel therapies and preventive strategies for various dermatological conditions. Further research is warranted to elucidate the full scope of AHR's contributions to dermatology and its potential as a therapeutic target.

A combination of three antioxidants decreases the impact of rural particulate pollution in Normal human keratinocytes

OBJECTIVE

It is well established that exposure of human skin to airborne pollution, particularly in the form of particulate matter sized 2.5 μm (PM2.5 ), is associated with oxidative stress, DNA damage and inflammation, leading to premature signs of skin aging. Because much of the damage results from oxidative stress, we examined the effects of a topical composition containing three antioxidants in an in vitro model system to assess the potential for amelioration of premature aging. The use of multiple antioxidants was of interest based on the typical composition of therapeutic skincare products. It is important to determine the efficacy of multiple antioxidants together and develop a short-term assay for larger scale efficacy testing.

METHODS

Normal human epidermal keratinocytes were exposed to a rural-derived source of PM2.5 in the presence and absence of an antioxidant mixture of resveratrol, niacinamide and GHK peptide. Endpoints related to inflammation, premature aging and carcinogenicity were monitored after 5 h of exposure and included IL-6, CXCL10, MMP-1 and NRF2. Differentially expressed genes were monitored by RNA-seq.

RESULTS

Pre-treatment of keratinocytes with the antioxidant preparation in the absence of PM2.5 reduced baseline levels of MMP-1, IL-6 and CYP1A1 and reduced PM2.5 -induced increases in all four endpoints, MMP-1, IL-6, CXCL10 and CYP1A1. Antioxidants significantly increased NRF2 protein in the presence of PM2.5 , indicating a protective response. RNA-seq interrogation of antioxidant-treated cells further showed increased expression of NRF2 inducible genes. The expression of CYP1A1 and genes related to aryl hydrocarbon activation were induced by PM2.5 and suppressed by antioxidants.

CONCLUSIONS

Specific signalling pathways known to be correlated with skin inflammation and aging were examined based on their suitability for use in efficacy testing for the prevention of skin damage due to ambient hydrocarbon pollution. Endpoints examined after only 5 h of exposure provide a useful method amenable to high through-put screening. The results obtained reinforce the concept that a multiple antioxidant preparation, topically applied, may reduce pro-inflammatory signalling and cellular damage and thereby reduce premature skin aging due to exposure to rural-derived airborne pollution.

Tackling microplastics pollution in global environment through integration of applied technology, policy instruments, and legislation

Microplastic pollution is a serious environmental problem that affects both aquatic and terrestrial ecosystems. Small particles with size of less than 5 mm, known as microplastics (MPs), persist in the environment and pose serious threats to various species from micro-organisms to humans. However, terrestrial environment has received less attention than the aquatic environment, despite being a major source of MPs that eventually reaches water body. To reflect its novelty, this work aims at providing a comprehensive overview of the current state of MPs pollution in the global environment and various solutions to address MP pollution by integrating applied technology, policy instruments, and legislation. This review critically evaluates and compares the existing technologies for MPs detection, removal, and degradation, and a variety of policy instruments and legislation that can support the prevention and management of MPs pollution scientifically. Furthermore, this review identifies the gaps and challenges in addressing the complex and diverse nature of MPs and calls for joint actions and collaboration from stakeholders to contain MPs. As water pollution by MPs is complex, managing it effectively requires their responses through the utilization of technology, policy instruments, and legislation. It is evident from a literature survey of 228 published articles (1961-2023) that existing water technologies are promising to remove MPs pollution. Membrane bioreactors and ultrafiltration achieved 90% of MPs removal, while magnetic separation was effective at extracting 88% of target MPs from wastewater. In biological process, one kg of wax worms could consume about 80 g of plastic/day. This means that 100 kg of wax worms can eat about 8 kg of plastic daily, or about 2.9 tons of plastic annually. Overall, the integration of technology, policy instrument, and legislation is crucial to deal with the MPs issues.

Contrasting Health Outcomes following a Severe Smoke Episode and Ambient Air Pollution in Early Life: Findings from an Australian Data Linkage Cohort Study of Hospital Utilization

BACKGROUND

Episodic spikes in air pollution due to landscape fires are increasing, and their potential for longer term health impacts is uncertain.

OBJECTIVE

Our objective is to evaluate associations between exposure in utero and in infancy to severe pollution from a mine fire, background ambient air pollution, and subsequent hospital care.

METHODS

We linked health records of births, emergency department (ED) visits, and hospitalizations of children born in the Latrobe Valley, Australia, 2012-2015, which included a severe pollution episode from a mine fire (9 February 2014 to 25 March 2014). We assigned modeled exposure estimates for fire-related and ambient particulate matter with an aerodynamic diameter of 2.5 μ m (PM 2.5 ) to residential address. We used logistic regression to estimate associations with hospital visits for any cause and groupings of infectious, allergic, and respiratory conditions. Outcomes were assessed for the first year of life in the in utero cohort and the year following the fire in the infant cohort. We estimated exposure-response for both fire-related and ambient PM 2.5 and also employed inverse probability weighting using the propensity score to compare exposed and not/minimally exposed children.

RESULTS

Prenatal exposure to fire-related PM 2.5 was associated with ED presentations for allergies/skin rash [odds ratio ( OR ) = 1.34 , 95% confidence interval (CI): 1.01, 1.76 per 240   μ g / m 3 increase]. Exposure in utero to ambient PM 2.5 was associated with overall presentations (OR = 1.18 , 95% CI: 1.05, 1.33 per 1.4   μ g / m 3 ) and visits for infections (ED: OR = 1.13 , 95% CI: 0.98, 1.29; hospitalizations: OR = 1.23 , 95% CI: 1.00, 1.52). Exposure in infancy to fire-related PM 2.5 compared to no/minimal exposure, was associated with ED presentations for respiratory (OR = 1.37 , 95% CI: 1.05, 1.80) and infectious conditions (any: OR = 1.21 , 95% CI: 0.98, 1.49; respiratory-related: OR = 1.39 , 95% CI: 1.05, 1.83). Early life exposure to ambient PM 2.5 was associated with overall ED visits (OR = 1.17 , 95% CI: 1.05, 1.30 per 1.4   μ g / m 3 increase).

DISCUSSION

Higher episodic and lower ambient concentrations of PM 2.5 in early life were associated with visits for allergic, respiratory, and infectious conditions. Our findings also indicated differences in associations at the two developmental stages. https://doi.org/10.1289/EHP12238.

Early-immune development in asthma: A review of the literature

This review presents a comprehensive examination of the various factors contributing to the immunopathogenesis of asthma from the prenatal to preschool period. We focus on the contributions of genetic and environmental components as well as the role of the nasal and gut microbiome on immune development. Predisposing genetic factors, including inherited genes associated with increased susceptibility to asthma, are discussed alongside environmental factors such as respiratory viruses and pollutant exposure, which can trigger or exacerbate asthma symptoms. Furthermore, the intricate interplay between the nasal and gut microbiome and the immune system is explored, emphasizing their influence on allergic immune development and response to environmental stimuli. This body of literature underscores the necessity of a comprehensive approach to comprehend and manage asthma, as it emphasizes the interactions of multiple factors in immune development and disease progression.

3-Bromo-4,5-dihydroxybenzaldehyde Protects Keratinocytes from Particulate Matter 2.5-Induced Damages

Cellular senescence can be activated by several stimuli, including ultraviolet radiation and air pollutants. This study aimed to evaluate the protective effect of marine algae compound 3-bromo-4,5-dihydroxybenzaldehyde (3-BDB) on particulate matter 2.5 (PM_2.5)-induced skin cell damage in vitro and in vivo. The human HaCaT keratinocyte was pre-treated with 3-BDB and then with PM_2.5. PM_2.5-induced reactive oxygen species (ROS) generation, lipid peroxidation, mitochondrial dysfunction, DNA damage, cell cycle arrest, apoptotic protein expression, and cellular senescence were measured using confocal microscopy, flow cytometry, and Western blot. The present study exhibited PM_2.5-generated ROS, DNA damage, inflammation, and senescence. However, 3-BDB ameliorated PM_2.5-induced ROS generation, mitochondria dysfunction, and DNA damage. Furthermore, 3-BDB reversed the PM_2.5-induced cell cycle arrest and apoptosis, reduced cellular inflammation, and mitigated cellular senescence in vitro and in vivo. Moreover, the mitogen-activated protein kinase signaling pathway and activator protein 1 activated by PM_2.5 were inhibited by 3-BDB. Thus, 3-BDB suppressed skin damage induced by PM_2.5.

The skin is no barrier to mixtures: Air pollutant mixtures and reported psoriasis or eczema in the Personalized Environment and Genes Study (PEGS)

BACKGROUND

Autoimmune (AI) diseases appear to be a product of genetic predisposition and environmental triggers. Disruption of the skin barrier causes exacerbation of psoriasis/eczema. Oxidative stress is a mechanistic pathway for pathogenesis of the disease and is also a primary mechanism for the detrimental effects of air pollution.

METHODS

We evaluated the association between autoimmune skin diseases (psoriasis or eczema) and air pollutant mixtures in 9060 subjects from the Personalized Environment and Genes Study (PEGS) cohort. Pollutant exposure data on six criteria air pollutants are publicly available from the Center for Air, Climate, and Energy Solutions and the Atmospheric Composition Analysis Group. For increased spatial resolution, we included spatially cumulative exposure to volatile organic compounds from sites in the United States Environmental Protection Agency Toxic Release Inventory and the density of major roads within a 5 km radius of a participant's address from the United States Geological Survey. We applied logistic regression with quantile g-computation, adjusting for age, sex, diagnosis with an autoimmune disease in family or self, and smoking history to evaluate the relationship between self-reported diagnosis of an AI skin condition and air pollution mixtures.

RESULTS

Only one air pollution variable, sulfate, was significant individually (OR = 1.06, p = 3.99E-2); however, the conditional odds ratio for the combined mixture components of PM2.5 (black carbon, sulfate, sea salt, and soil), CO, SO2, benzene, toluene, and ethylbenzene is 1.10 (p-value = 5.4E-3).

SIGNIFICANCE

While the etiology of autoimmune skin disorders is not clear, this study provides evidence that air pollutants are associated with an increased prevalence of these disorders. The results provide further evidence of potential health impacts of air pollution exposures on life-altering diseases.

SIGNIFICANCE AND IMPACT STATEMENT

The impact of air pollution on non-pulmonary and cardiovascular diseases is understudied and under-reported. We find that air pollution significantly increased the odds of psoriasis or eczema in our cohort and the magnitude is comparable to the risk associated with smoking exposure. Autoimmune diseases like psoriasis and eczema are likely impacted by air pollution, particularly complex mixtures and our study underscores the importance of quantifying air pollution-associated risks in autoimmune disease.

The characteristics of PM emissions from construction sites during the earthwork and foundation stages: an empirical study evidence

The bulk of the particulate matter (PM) emissions generated during construction projects are significantly released during the earthwork and foundation stages. To reduce and control these emissions, it is necessary to have reliable data on their characteristics. However, construction PM are poorly characterized because their composition depends on several factors (e.g., weather and reduction measures) and various on-site activities whose effects may interact. To address these challenges, a long-term quantitative empirical study using advanced statistical methods was performed on a real construction project during the whole earthwork and foundation stages. The upwind-downwind method was used to collect data on PM emissions throughout the earthwork and foundation construction process, and correlation analysis, paired samples t-test, and partial least squares regression (PLS) were used to analyze TSP, PM₁₀, and PM_2.5 emissions and their relationships with various influencing factors. The results showed that both earthwork and foundation constructions generate substantial PM emissions because there were differences with statistical significances in the PM levels measured upwind and downwind of the construction site. TSP and PM₁₀ emissions correlated moderately with humidity and wind speed. However, temperature and atmospheric pressure did not correlate significantly with any of the measured emissions. The main activities responsible for PM emissions during the earthwork and foundation construction stages were hammer piling, waste stacking, and materials transportation. Water spraying was found to effectively reduce TSP and PM₁₀ emissions, while the use of a fog cannon more effectively reduced PM_2.5 emissions. Construction PM is an important source of atmospheric pollution in cities; the findings presented herein provide cornerstone and knowledge to guide efforts for reducing its impact.

Chlorogenic Acid, a Component of Oenanthe javanica (Blume) DC., Attenuates Oxidative Damage and Prostaglandin E2 Production Due to Particulate Matter 10 in HaCaT Keratinocytes

Oenanthe javanica (OJ) is a perennial herb that grows wildly or is cultivated in Asia, and it is used as food or in traditional medicine. The antioxidant and anti-inflammatory effects of OJ-derived materials have been extensively explored previously, but their effects on the cytotoxicity of air pollution are currently unknown. Therefore, the present study aimed to evaluate the effect of the hot water extract of OJ on atmospheric particulate matter 10 (PM10)-induced cytotoxicity and oxidative damage in human HaCaT keratinocytes, and to identify its active ingredient and mechanism of action. When the hot water extract of OJ was divided into methylene chloride, ethyl acetate (EA), n-butanol (BA), and water fractions, caffeic acid was enriched in the EA fraction and chlorogenic acid was enriched in the BA fraction. PM10 increased reactive oxygen species (ROS) production, lipid peroxidation, protein carbonylation, and inflammatory prostaglandin (PG) E2 production in cells. The BA fraction reduced the PM10-induced ROS production in cells more effectively than the total extract and other solvent fractions. Chlorogenic acid was more effective in reducing ROS levels than caffeic acid and N-acetyl cysteine (NAC). Chlorogenic acid attenuated the increase in lipid peroxidation and the PG E2 production of cells due to PM10 exposure. Of the genes involved in PG E2 production, phospholipase A2 group IVA (PLA2G4A), Prostaglandin-endoperoxide synthase 1 (PTGS1), and 2 (PTGS2) were transcriptionally up-regulated by PM10, whereas phospholipase A2 group IIA (PLA2G2A) was down-regulated and prostaglandin E synthetase 1 (PTGES1) and 2 (PTGES2) were a little altered. The PM10-induced increase in PLA2G4A mRNA was alleviated by chlorogenic acid and NAC. Accordingly, PM10 increased the expression levels of cytosolic phospholipase A2 (cPLA2) protein and its phosphorylated form, which were attenuated by chlorogenic acid and NAC. Thus, chlorogenic acid may attenuate the PM10-induced PG E2 production through the suppression of PLA2G4A mRNA and cPLA2 protein expressions. This study suggests that chlorogenic acid contained in OJ extract may help alleviate the oxidative damage to and inflammatory responses of the skin cells due to exposure to air pollutants.

Epicutaneous Sensitization and Food Allergy: Preventive Strategies Targeting Skin Barrier Repair-Facts and Challenges

Food allergy represents a growing public health and socio-economic problem with an increasing prevalence over the last two decades. Despite its substantial impact on the quality of life, current treatment options for food allergy are limited to strict allergen avoidance and emergency management, creating an urgent need for effective preventive strategies. Advances in the understanding of the food allergy pathogenesis allow to develop more precise approaches targeting specific pathophysiological pathways. Recently, the skin has become an important target for food allergy prevention strategies, as it has been hypothesized that allergen exposure through the impaired skin barrier might induce an immune response resulting in subsequent development of food allergy. This review aims to discuss current evidence supporting this complex interplay between the skin barrier dysfunction and food allergy by highlighting the crucial role of epicutaneous sensitization in the causality pathway leading to food allergen sensitization and progression to clinical food allergy. We also summarize recently studied prophylactic and therapeutic interventions targeting the skin barrier repair as an emerging food allergy prevention strategy and discuss current evidence controversies and future challenges. Further studies are needed before these promising strategies can be routinely implemented as prevention advice for the general population.

Anti-Pollutant Activity of Porphyra yezoensis Water Extract and Its Active Compound, Porphyra 334, against Urban Particulate Matter-Induced Keratinocyte Cell Damage

Urban particulate matter (UPM) causes skin aging and inflammatory reactions by influencing skin cells through the aryl hydrocarbon receptor (AhR) signaling pathway. Porphyra yezoensis (also known as Pyropia yezoensis), a red alga belonging to the Bangiaceae family, is an edible red seaweed. Here, we examined the anti-pollutant effect of P. yezoensis water extract. While UPM treatment induced xenobiotic response element (XRE) promoter luciferase activity, P. yezoensis water extract reduced UPM-induced XRE activity. Next, we isolated an active compound from P. yezoensis and identified it as porphyra 334. Similar to the P. yezoensis water extract, porphyra 334 attenuated UPM-induced XRE activity. Moreover, although UPM augmented AhR nuclear translocation, which led to an increase in cytochrome P450 1A1 (CYP1A1) mRNA levels, these effects were reduced by porphyra 334. Moreover, UPM induced the production of reactive oxygen species (ROS) and reduced cell proliferation. These effects were attenuated in response to porphyra 334 treatment. Furthermore, our results revealed that the increased ROS levels induced by UPM treatment induced transient receptor potential vanilloid 1 (TRPV1) activity, which is related to skin aging and inflammatory responses. However, porphyra 334 treatment reduced this reaction by inhibiting ROS production induced by CYP1A1 activation. This indicates that porphyra 334, an active compound of P. yezoensis, attenuates UP-induced cell damage by inhibiting AhR-induced ROS production, which results in a reduction in TRPV1 activation, leading to cell proliferation. This also suggests that porphyra 334 could protect the epidermis from harmful pollutants.

Air Pollution and Atopic Dermatitis, from Molecular Mechanisms to Population-Level Evidence: A Review

Atopic dermatitis (AD) has increased in prevalence to become the most common inflammatory skin condition globally, and geographic variation and migration studies suggest an important role for environmental triggers. Air pollution, especially due to industrialization and wildfires, may contribute to the development and exacerbation of AD. We provide a comprehensive, multidisciplinary review of existing molecular and epidemiologic studies on the associations of air pollutants and AD symptoms, prevalence, incidence, severity, and clinic visits. Cell and animal studies demonstrated that air pollutants contribute to AD symptoms and disease by activating the aryl hydrocarbon receptor pathway, promoting oxidative stress, initiating a proinflammatory response, and disrupting the skin barrier function. Epidemiologic studies overall report that air pollution is associated with AD among both children and adults, though the results are not consistent among cross-sectional studies. Studies on healthcare use for AD found positive correlations between medical visits for AD and air pollutants. As the air quality worsens in many areas globally, it is important to recognize how this can increase the risk for AD, to be aware of the increased demand for AD-related medical care, and to understand how to counsel patients regarding their skin health. Further research is needed to develop treatments that prevent or mitigate air pollution-related AD symptoms.

[Atopic dermatitis in adults during the COVID-19 pandemic]

OBJECTIVE

To evaluate the clinical course of atopic dermatitis (AD) in adults during the COVID-19 pandemic and to evaluate their comorbidities and cardiovascular risk.

METHODS

A cross-sectional study was conducted in adults with AD. Severity and control of AD, quality of life, levels of psychological stress, depression and cardiovascular risk were measured.

RESULTS

Forty-two patients were included. A decrease in POEM score (11.83 vs 10.12; p=0.004) and PO-SCORAD (37.77 vs 32.49; p= 0.001) was observed in comparison to the scores at pandemic onset. The quality of life correlated with the severity of AD (p<0.0001) while the levels of stress and depression did not show association. Most patients had a low cardiovascular risk.

CONCLUSIONS

The results suggest a decrease in the current severity of AD compared with severity before pandemic. Quality of life is associated with AD severity.

Effects of ambient air pollution on outpatient visits for psoriasis in Wuhan, China: a time-series analysis

BACKGROUND

Psoriasis can be provoked by both external and internal factors. The effects of environmental factors on psoriasis remain unclear.

OBJECTIVES

To investigate the effects of air pollution on outpatient visits for psoriasis.

METHODS

A distributed lag nonlinear model following quasi-Poisson regression was used to evaluate the lag effects of air pollutants on psoriasis outpatient visits, adjusting for potential confounders. Stratified analyses were performed to identify potential effect modifications by sex, age and season.

RESULTS

In total, 13 536 outpatient visits for psoriasis were recorded in Wuhan, China from 1 January 2015 to 31 December 2019. In the single-pollutant model, exposures to particulate matter (PM) smaller than 2.5 μm (PM2.5), PM smaller than 10 μm (PM10), NO2 and SO2 were found to be significantly associated with increased daily psoriasis outpatient visits. For the largest effects, a 10-μg m-3 increase in concentrations of PM2.5 (lag1), PM10 (lag1), NO2 (lag0) and SO2 (lag3) corresponded to 0.32% [95% confidence interval (CI) 0.01-0.63], 0.26% (95% CI 0.05-0.48), 0.98% (95% CI 0.01-1.96) and 2.73% (95% CI 1.01-4.47) increases in psoriasis outpatient visits, respectively. In the two-pollutant model, only NO2 showed significant and stable effects on the outpatient visits for psoriasis.

CONCLUSIONS

Ambient air pollution, especially NO2, appears to be significantly associated with an increased risk of outpatient visits for psoriasis in Wuhan, China. Air pollution control and exposure prevention could be effective measures to relieve the symptoms of psoriasis among these patients.

Exposure to air pollution and incidence of atopic dermatitis in the general population: A national population-based retrospective cohort study

BACKGROUND

To date, little evidence is available to determine whether atopic dermatitis (AD) can be caused by exposure to air pollutants, including gases and particulate matter.

OBJECTIVE

We aimed to evaluate the relationship between air pollutants and incidence of AD using the National Health Insurance Service-National Sample Cohort database.

METHODS

We included 209,168 subjects from the general population previously not diagnosed with AD between 2008 and 2013. Long-term average concentration of air pollutants before diagnosis was calculated for each subject.

RESULTS

For 1,030,324 person-years, incident cases of AD were observed in 3203 subjects. There was a significant positive association between incidence of AD and long-term average concentration of particulate matter smaller than 2.5 μm in diameter (hazard ratio [HR], 1.420; 95% CI, 1.392-1.448; for 1 μg/m³), particulate matter smaller than 10 μm in diameter (HR, 1.333, 95% CI, 1.325-1.341; for 1 μg/m³), sulfur dioxide (HR, 1.626; 95% CI, 1.559-1.695; for 1 parts per billion), nitrogen dioxide (HR, 1.200; 95% CI, 1.187-1.212; for 1 parts per billion), and carbon monoxide (HR, 1.005; 95% CI, 1.004-1.005; for 1 parts per billion) after adjusting for age, sex, income, comorbid diseases, and meteorologic variables.

LIMITATIONS

The National Health Insurance Service database lacks detailed information on individual subjects.

CONCLUSIONS

This study demonstrated that long-term exposure to air pollutants, including gases and particulate matter, is an independent risk factor for developing AD.

Efficacy and Safety of COVID-19 Treatment Using Convalescent Plasma Transfusion: Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials

This study investigated the efficacy and safety of convalescent plasma (CP) transfusion against the coronavirus disease 2019 (COVID-19) via a systematic review and meta-analysis of randomized controlled trials (RCTs). A total of 5467 articles obtained from electronic databases were assessed; however, only 34 RCTs were eligible after manually screening and eliminating unnecessary studies. The beneficial effect was addressed by assessing the risk ratio (RR) and standardized mean differences (SMDs) of the meta-analysis. It was demonstrated that CP therapy is not effective in improving clinical outcomes, including reducing mortality with an RR of 0.88 [0.76; 1.03] (I2 = 68% and p = 0.10) and length of hospitalization with SMD of -0.47 [-0.95; 0.00] (I2 = 99% and p = 0.05). Subgroup analysis provided strong evidence that CP transfusion does not significantly reduce all-cause mortality compared to standard of care (SOC) with an RR of 1.01 [0.99; 1.03] (I2 = 70% and p = 0.33). In addition, CP was found to be safe for and well-tolerated by COVID-19 patients as was the SOC in healthcare settings. Overall, the results suggest that CP should not be applied outside of randomized trials because of less benefit in improving clinical outcomes for COVID-19 treatment.

Detrimental correlation between air pollution with skin aging in Taiwan population

Dissecting the complex relationships between skin aging and air pollution has been an ongoing effort. The increased exposure to air pollution over time imposed a negative effect on skin. This study explores the correlation between skin aging in the Asian population and levels of air pollutants to show different relationship between the two. This study was retrospective and included 389 patients, age between 30 and 74, who planned to receive a session of laser treatment for skin disorders in Kaohsiung Medical University Hospital (KMUH) from 2006 to 2019. Preoperative skin condition quantified by VISIA Complexion Analysis System (Canfield Imaging Systems, Fierfield, NJ, US). Eight air pollutants such as carbon monoxide (CO), non-methane hydrocarbon (NMHC), nitrogen oxides (NO, NO2, and NOx), particulate matters (PM2.5 and PM10), ozone (O3), sulfur dioxide (SO2) and 8 skin condition such as spots, wrinkles, textures, pores, ultraviolet spots (UV spots), brown spots, red area, and porphyrin were analyzed to explore correlation between air pollution and skin aging. Strong correlation was found between NMHC exposure and texture, pores and brown spots formation. A positive correlation between O3 and better VISIA texture and pores scores was found. Brown spots was found to negatively associate with CO, NMHC, NO2, NOx, PM10, PM2.5, and SO2. The skin condition of population over age 45 affected by CO, NMHC, NO2, NOx, PM2.5, PM10, and SO2. Skin condition of the bottom 10% strongly correlates with exposure to PM10 and SO2, whereas skin condition of the top 10% was affected by PM10. Air pollutants such as CO, NO2, NOx, PM2.5, PM10, SO2, and NMHC were found to correlate with negative skin quality strongly. In contrast, O3 exposure is associated with less texture and pores. Future studies are warranted to further appreciate the relationships between air pollutants and skin condition.

Outdoor air quality and human health: An overview of reviews of observational studies

The epidemiological evidence supporting putative associations between air pollution and health-related outcomes continues to grow at an accelerated pace with a considerable heterogeneity and with varying consistency based on the outcomes assessed, the examined surveillance system, and the geographic region. We aimed to evaluate the strength of this evidence base, to identify robust associations as well as to evaluate effect variation. An overview of reviews (umbrella review) methodology was implemented. PubMed and Scopus were systematically screened (inception-3/2020) for systematic reviews and meta-analyses examining the association between air pollutants, including CO, NO_X, NO₂, O₃, PM₁₀, PM_2.5, and SO₂ and human health outcomes. The quality of systematic reviews was evaluated using AMSTAR. The strength of evidence was categorized as: strong, highly suggestive, suggestive, or weak. The criteria included statistical significance of the random-effects meta-analytical estimate and of the effect estimate of the largest study in a meta-analysis, heterogeneity between studies, 95% prediction intervals, and bias related to small study effects. Seventy-five systematic reviews of low to moderate methodological quality reported 548 meta-analyses on the associations between outdoor air quality and human health. Of these, 57% (N = 313) were not statistically significant. Strong evidence supported 13 associations (2%) between elevated PM_2.5, PM₁₀, NO₂, and SO₂ concentrations and increased risk of cardiorespiratory or pregnancy/birth-related outcomes. Twenty-three (4%) highly suggestive associations were identified on elevated PM_2.5, PM₁₀, O₃, NO₂, and SO₂ concentrations and increased risk of cardiorespiratory, kidney, autoimmune, neurodegenerative, cancer or pregnancy/birth-related outcomes. Sixty-seven (12%), and 132 (24%) meta-analyses were graded as suggestive, and weak, respectively. Despite the abundance of research on the association between outdoor air quality and human health, the meta-analyses of epidemiological studies in the field provide evidence to support robust associations only for cardiorespiratory or pregnancy/birth-related outcomes.

Human skin responses to environmental pollutants: A review of current scientific models

Whatever the exposure route, chemical, physical and biological pollutants modify the whole organism response, leading to nerve, cardiac, respiratory, reproductive, and skin system pathologies. Skin acts as a barrier for preventing pollutant modifications. This review aims to present the available scientific models, which help investigate the impact of pollution on the skin. The research question was "Which experimental models illustrate the impact of pollution on the skin in humans?" The review covered a period of 10 years following a PECO statement on in vitro, ex vivo, in vivo and in silico models. Of 582 retrieved articles, 118 articles were eligible. In oral and inhalation routes, dermal exposure had an important impact at both local and systemic levels. Healthy skin models included primary cells, cell lines, co-cultures, reconstructed human epidermis, and skin explants. In silico models estimated skin exposure and permeability. All pollutants affected the skin by altering elasticity, thickness, the structure of epidermal barrier strength, and dermal extracellular integrity. Some specific models concerned wound healing or the skin aging process. Underlying mechanisms were an exacerbated inflammatory skin reaction with the modulation of several cytokines and oxidative stress responses, ending with apoptosis. Pathological skin models revealed the consequences of environmental pollutants on psoriasis, atopic dermatitis, and tumour development. Finally, scientific models were used for evaluating the safety and efficacy of potential skin formulations in preventing the skin aging process or skin irritation after repeated contact. The review gives an overview of scientific skin models used to assess the effects of pollutants. Chemical and physical pollutants were mainly represented while biological contaminants were little studied. In future developments, cell hypoxia and microbiota models may be considered as more representative of clinical situations. Models considering humidity and temperature variations may reflect the impact of these changes.

Ambient air pollutants increase the risk of immunoglobulin E-mediated allergic diseases: a systematic review and meta-analysis

Immunoglobulin E (IgE)-mediated allergic diseases, including eczema, atopic dermatitis (AD), and allergic rhinitis (AR), have increased prevalence in recent decades. Recent studies have proved that environmental pollution might have correlations with IgE-mediated allergic diseases, but existing research findings were controversial. Thus, we performed a comprehensive meta-analysis from published observational studies to evaluate the risk of long-term and short-term exposure to air pollutants on eczema, AD, and AR in the population (per 10-μg/m3 increase in PM2.5 and PM10; per 1-ppb increase in SO2, NO2, CO, and O3). PubMed, Embase, and Web of Science were searched to identify qualified literatures. The Cochran Q test was used to assess heterogeneity and quantified with the I2 statistic. Pooled effects and the 95% confidence intervals (CIs) were used to evaluate outcome effects. A total of 55 articles were included in the study. The results showed that long-term and short-term exposure to PM10 increased the risk of eczema (PM10, RRlong = 1.583, 95% CI: 1.328, 1.888; RRshort = 1.006, 95% CI: 1.003-1.008) and short-term exposure to NO2 (RRshort = 1.009, 95% CI: 1.008-1.011) was associated with eczema. Short-term exposure to SO2 (RRshort: 1.008, 95% CI: 1.001-1.015) was associated with the risk of AD. For AR, PM2.5 (RRlong = 1.058, 95% CI: 1.014-1.222) was harmful in the long term, and short-term exposure to PM10 (RRshort: 1.028, 95% CI: 1.008-1.049) and NO2 (RRshort: 1.018, 95% CI: 1.007-1.029) were risk factors. The findings indicated that exposure to air pollutants might increase the risk of IgE-mediated allergic diseases. Further studies are warranted to illustrate the potential mechanism for air pollutants and allergic diseases.

Comparison of Malassezia spp. colonization between human skin exposed to high and low ambient air pollution

BACKGROUND

The skin microbiota is essential for human health; altered skin microbiome colonization and homeostasis may be associated with several inflammatory skin conditions and other inflammatory diseases. The effects of particulate matter of diameter less than 2.5 micrometers (PM2.5) on the skin and the skin microbiome are poorly understood. Malassezia spp. are commensal fungi commonly found on the human skin, and they also play a pathogenic role in various skin diseases. It is hypothesized that the exposure of human skin to air pollution with a high concentration of PM2.5 might be associated with Malassezia spp. colonization. The aim of this study was to compare Malassezia spp. colonization on healthy human skin between people living in two major cities in Thailand with different air qualities: one city with highly polluted ambient air and the other with less polluted air.

METHODS

Skin microbiome samples from 66 participants were collected using swabbing and scraping techniques. The skin fungal composition was analyzed using high-throughput sequencing based on internal transcribed spacer 2 (ITS2) rDNA.

RESULTS

A significant difference was found in alpha and beta diversities and the relative abundance of fungal profiles between the groups. The relative abundance of Malassezia spp. was found to be significantly higher in the highly polluted area than in the less polluted area.

CONCLUSION

This study demonstrates that ambient air polluted with high concentrations of PM2.5 may alter Malassezia spp. colonization on healthy human skin, which could lead to dysbiosis of the cutaneous ecosystem and eventually result in some skin disorders.

Transepidermal water loss (TEWL): Environment and pollution-A systematic review

Introduction

Transepidermal water loss (TEWL) is an objective measurement of skin integrity measured as the amount of water lost across the stratum corneum. TEWL varies greatly across variables such as age and anatomic location, and disruptions in the skin barrier have been linked to inflammatory dermatoses such as psoriasis and atopic dermatitis. Impact of environmental conditions and pollution on TEWL has yet to be determined. Accordingly, this review summarizes effects of environmental conditions and pollution on TEWL.

Methods

A comprehensive literature search was performed using Embase, PubMed, and Web of Science to find human studies that provided data on environmental conditions and/or pollution and TEWL.

Results

In total, 15 studies were included, with 11 studies examining environmental and seasonal conditions on TEWL and four examining pollution. All studies examining pollution showed increased TEWL in people exposed to particulate matter or NO2. Contradictory results were found on the effects of season and climate across the 11 studies, with no consensus reached.

Conclusion

Exposure to pollution is reported to cause increases in TEWL, likely through free radical damage. Significant discrepancies exist among current literature as to the effects of season and climate on TEWL. There is a need to continue examining environmental variables other than temperature and relative humidity, such as atmospheric and steam pressure, that may impact TEWL.

Epithelial barrier hypothesis: Effect of the external exposome on the microbiome and epithelial barriers in allergic disease

Environmental exposure plays a major role in the development of allergic diseases. The exposome can be classified into internal (e.g., aging, hormones, and metabolic processes), specific external (e.g., chemical pollutants or lifestyle factors), and general external (e.g., broader socioeconomic and psychological contexts) domains, all of which are interrelated. All the factors we are exposed to, from the moment of conception to death, are part of the external exposome. Several hundreds of thousands of new chemicals have been introduced in modern life without our having a full understanding of their toxic health effects and ways to mitigate these effects. Climate change, air pollution, microplastics, tobacco smoke, changes and loss of biodiversity, alterations in dietary habits, and the microbiome due to modernization, urbanization, and globalization constitute our surrounding environment and external exposome. Some of these factors disrupt the epithelial barriers of the skin and mucosal surfaces, and these disruptions have been linked in the last few decades to the increasing prevalence and severity of allergic and inflammatory diseases such as atopic dermatitis, food allergy, allergic rhinitis, chronic rhinosinusitis, eosinophilic esophagitis, and asthma. The epithelial barrier hypothesis provides a mechanistic explanation of how these factors can explain the rapid increase in allergic and autoimmune diseases. In this review, we discuss factors affecting the planet's health in the context of the 'epithelial barrier hypothesis,' including climate change, pollution, changes and loss of biodiversity, and emphasize the changes in the external exposome in the last few decades and their effects on allergic diseases. In addition, the roles of increased dietary fatty acid consumption and environmental substances (detergents, airborne pollen, ozone, microplastics, nanoparticles, and tobacco) affecting epithelial barriers are discussed. Considering the emerging data from recent studies, we suggest stringent governmental regulations, global policy adjustments, patient education, and the establishment of individualized control measures to mitigate environmental threats and decrease allergic disease.

Acute and lag effects of ambient fine particulate matter on the incidence of dyslipidemia in Chengdu, China: A time-series study

High levels of ambient fine particulate matter (PM_2.5) might increase the risk of death due to cardiovascular diseases (CVDs). As a critical risk factor for CVDs, dyslipidemia can cause CVDs or exacerbate pre-existing ones. This study aimed to investigate whether a short-time exposure to PM_2.5 leads to dyslipidemia (HyperTC, HyperLDL-C, HyperTG and HypoHDL-C) in adults. The serum lipid data were provided by the Sichuan Provincial People's Hospital Medical Examination Center. We included 309,654 subjects aged 18-79 between May 10, 2015, and May 10, 2017. An advanced distributed lag nonlinear model (DLNM) was applied to investigate the acute and lag effects of ambient PM_2.5 on the risk of dyslipidemia. This study was also stratified by sex, age, BMI and season to examine potential effect modification. We observed that the associations between an interquartile increase in PM_2.5 (43 μg/m³) and dyslipidemia were [relative risk (RR); 95% confidence interval (CI)]: 1.042 (1.013, 1.071) for HyperLDL-C and 1.027 (1.006, 1.049) for HyperTC at lag0 day. The lag effects were found at lag6 day for HyperLDL-C, in lag4-6 days for HyperTC and lag4-7 days for HyperTG. Short-term exposure to ambient PM_2.5 was related to dyslipidemia and the effect modification was observed in the subgroup analysis. The female and normal-weight populations were more susceptible to the risks of PM_2.5 on HyperLDL-C and HyperTC.

Reducing Construction Dust Pollution by Planning Construction Site Layout

Many construction activities generate fine particles and severely threaten the physical health of construction workers. Although many dust control measures are implemented in the industry, the occupational health risks still exist. In order to improve the occupational health level, this study proposes a new method of reducing the construction dust pollution through a reasonable site layout plan. This method is based on the field measurement and dust diffusion law. The dust diffusion law can be fitted based on the field monitoring data. With diffusion law, the average dust concentration exposed to workers of different site layouts can be simulated. In addition, the cost of the dust control method is a concern for site managers. Therefore, the total transportation cost reduction is another optimization objective. Finally, the multi-objective particle swarm optimization (MOPSO) algorithm is used to search for an optimized site layout that can reduce dust pollution and transportation cost simultaneously. The result shows that average dust concentration exposed to workers and total transportation cost are significantly reduced by 60.62% and 44.3%, respectively. This paper quantifies the construction dust pollution and provides site managers with a practical solution to reduce the construction dust pollution at low cost.

Antioxidant Effects of Korean Propolis in HaCaT Keratinocytes Exposed to Particulate Matter 10

Air pollution causes oxidative stress that leads to inflammatory diseases and premature aging of the skin. The purpose of this study was to examine the antioxidant effect of Korean propolis on oxidative stress in human epidermal HaCaT keratinocytes exposed to particulate matter with a diameter of less than 10 μm (PM₁₀). The total ethanol extract of propolis was solvent-fractionated with water and methylene chloride to divide into a hydrophilic fraction and a lipophilic fraction. The lipophilic fraction of propolis was slightly more cytotoxic, and the hydrophilic fraction was much less cytotoxic than the total extract. The hydrophilic fraction did not affect the viability of cells exposed to PM₁₀, but the total propolis extract and the lipophilic fraction aggravated the toxicity of PM₁₀. The total extract and hydrophilic fraction inhibited PM₁₀-induced ROS production and lipid peroxidation in a concentration-dependent manner, whereas the lipophilic fraction did not show such effects. High-performance liquid chromatography with photodiode array detection (HPLC-DAD) analysis showed that the hydrophilic fraction contained phenylpropanoids, such as caffeic acid, p-coumaric acid, and ferulic acid, whereas the lipophilic faction contained caffeic acid phenethyl ester (CAPE). The former three compounds inhibited PM₁₀-induced ROS production, lipid peroxidation, and/or glutathione oxidation, and ferulic acid was the most effective among them, but CAPE exhibited cytotoxicity and aggravated the toxicity of PM₁₀. This study suggests that Korean propolis, when properly purified, has the potential to be used as a cosmetic material that helps to alleviate the skin toxicity of air pollutants.

Air Pollution and Weather Conditions Are Associated with Daily Outpatient Visits of Atopic Dermatitis in Shanghai, China

BACKGROUND

Non-optimum weather conditions and air pollution have the potential to increase the risk of atopic dermatitis (AD), but the associations are rarely evaluated, especially in developing countries.

OBJECTIVE

To investigate the independent influence and interaction effects of meteorological factors and air pollutants on the onset of AD.

METHODS

Daily data on outpatient visits of AD were obtained from Shanghai Dermatology Hospital and comprised 34,633 patients during the period from January 2013 to December 2018. Meteorological conditions and air pollutant concentrations in Shanghai, China, during the 6-year period were collected. We applied the overdispersed generalized additive model and the distributed lag model to explore the short-term cumulative effects of environmental factors on AD.

RESULTS

AD symptoms were aggravated by extreme low temperature (1st percentile, 0.5°C) (RR = 1.32, 95% CI: 1.16-1.51) and per 10 unit decrease of humidity (RR = 1.10, 95% CI: 1.12-2.47). The increased concentration of air pollutants except ozone (O3) contributed to the increased risk of AD outpatients. A 10 μg/m3 increase in sulfur dioxide (SO2) and nitrogen dioxide (NO2) were associated with 6.03% (95% CI: 2.29%, 9.91%), and 1.96% (95% CI: 0.46%, 3.48%) increase of AD outpatients. AD patients in the 8- to 17-year-old group were most susceptible to extreme low temperature, and patients in the 0- to 7-year-old group were most susceptible to air pollutants, including particulate matter (PM10), SO2, and NO2. Men were more sensitive to the effects of extreme low temperature than women, while women were more vulnerable to air pollutants. The adverse effects of SO2 and NO2 on AD can be enhanced significantly by the warm season or other pollutants.

CONCLUSION

Exposure to a lower temperature, lower humidity, and higher levels of air pollutants is significantly associated with increased risks of AD incidence. These impacts were more pronounced in children less than 7 years old, women, and warm seasons.

A Machine Learning-Based Study of the Effects of Air Pollution and Weather in Respiratory Disease Patients Visiting Emergency Departments

Background. To date, investigating respiratory disease patients visiting the emergency departments related with fined dust is limited. This study aimed to analyze the effects of two variable-weather and air pollution on respiratory disease patients who visited emergency departments. Methods. This study utilized the National Emergency Department Information System (NEDIS) database. The meteorological data were obtained from the National Climate Data Service. Each weather factor reflected the accumulated data of 4 days: a patient’s visit day and 3 days before the visit day. We utilized the RandomForestRegressor of scikit-learn for data analysis. Result. The study included 525,579 participants. This study found that multiple variables of weather and air pollution influenced the respiratory diseases of patients who visited emergency departments. Most of the respiratory disease patients had acute upper respiratory infections [J00–J06], influenza [J09–J11], and pneumonia [J12–J18], on which PM10 following temperature and steam pressure was the most influential. As the top three leading causes of admission to the emergency department, pneumonia [J12–J18], acute upper respiratory infections [J00–J06], and chronic lower respiratory diseases [J40–J47] were highly influenced by PM10. Conclusion. Most of the respiratory patients visiting EDs were diagnosed with acute upper respiratory infections, influenza, and pneumonia. Following temperature, steam pressure and PM10 had influential relations with these diseases. It is expected that the number of respiratory disease patients visiting the emergency departments will increase by day 3 when the steam pressure and temperature values are low, and the variables of air pollution are high. The number of respiratory disease patients visiting the emergency departments will increase by day 3 when the steam pressure and temperature values are low, and the variables of air pollution are high.

The association between short-term ambient air pollution and acne vulgaris outpatient visits: a hospital-based time-series analysis in Xi'an

Recent studies have suggested that exposure to ambient airborne pollutants is associated with inflammatory skin diseases, but the epidemiological evidence regarding the association between air pollution and acne vulgaris is limited. To address that, a hospital-based time-series analysis was conducted in Xi'an, a metropolitan in northwest China. A total of 71,625 outpatient visits for acne from 2010 to 2013 were identified. The mean daily concentrations of PM10, SO2, and NO2 were 142.6 μg/m3, 44.7 μg/m3, and 48.5 μg/m3, and all were higher than WHO air quality guidelines. A generalized additive model was used to analyze the relationship between short-term ambient air pollution exposure and outpatient visits for acne. The gender- and age-specific analyses were conducted as well. The results showed that the increase of SO2 and NO2 concentrations corresponded to a significant rise in the number of outpatient visits for acne at lag 0 in both single-lag and cumulative exposure models. Both SO2 and NO2 were positively associated with acne outpatient visits for both males and females. In age-specific analyses, the effect estimate of PM10 was only significant for adults over 30 years old; SO2 was significantly associated with acne visits in children and adolescents (<21 years) and young adults (21-30 years); and NO2 was significantly associated with acne visits in all age subgroups. In conclusion, short-term exposure to ambient air pollutants (PM10, SO2, or NO2) with the average levels above WHO limits was associated with increased risk of outpatient visits for both teenage acne and adult acne. Moreover, the effects of air pollutants may vary with age.

AHR and NRF2 in Skin Homeostasis and Atopic Dermatitis

Skin is constantly exposed to environmental insults, including toxic chemicals and oxidative stress. These insults often provoke perturbation of epidermal homeostasis and lead to characteristic skin diseases. AHR (aryl hydrocarbon receptor) and NRF2 (nuclear factor erythroid 2-related factor 2) are transcription factors that induce a battery of cytoprotective genes encoding detoxication and antioxidant enzymes in response to environmental insults. In addition to their basic functions as key regulators of xenobiotic and oxidant detoxification, recent investigations revealed that AHR and NRF2 also play critical roles in the maintenance of skin homeostasis. In fact, specific disruption of AHR function in the skin has been found to be associated with the pathogenesis of various skin diseases, most prevalently atopic dermatitis (AD). In this review, current knowledge on the roles that AHR and NRF2 play in epidermal homeostasis was summarized. Functional annotations of genetic variants, both regulatory and nonsynonymous SNPs, identified in the AHR and NRF2 loci in the human genome were also summarized. Finally, the possibility that AHR and NRF2 serve as therapeutic targets of AD was assessed.

Defining the Relationship between Daily Exposure to Particulate Matter and Hospital Visits by Psoriasis Patients

Background

Although particulate matter likely provokes inflammatory reactions in those with chronic skin disorders like atopic dermatitis, no study has examined the relationship between particulate matter and psoriasis exacerbation.

Objective

This study evaluated possible associations between particulate matter and hospital visits for psoriasis patients in 7 major cities in South Korea.

Methods

We investigated the relationship between psoriasis and particulate matter. To do this, we used psoriasis patient data from the Korean National Health Insurance Service database. In addition, PM₁₀ and PM_2.5 concentration data spanning a 3-year time frame were obtained from the Korea Environment Corporation.

Results

A pattern analysis generated by the sample cross-correlation function and time series regression showed a correlation between particulate matter concentration and the number of hospital visits by psoriasis patients. However, the prewhitening method, which minimizes the effects of other variables besides particulate matter, revealed no correlation between the two.

Conclusion

This study suggests that particulate matter has no impact on hospital visit frequency among psoriasis patients in South Korean urban areas.

Short-term exposure of PM2.5 and PM10 increases the number of outpatients with eczema in Guangzhou: A time-series study

Background

The worldwide prevalence of eczema has continued to rise over the past decades. This has led to the emphasis on the association between air pollution and eczema. This study investigated the relationship between daily exposure to air pollution and the number of eczema outpatient visits in Guangzhou with the overarching goal of providing novel insights on the interventions for eczema aggravation and prevention.

Methods

Daily air pollution data, meteorological data, and the number of eczema outpatients were obtained from 18 January 2013 to 31 December 2018 in Guangzhou. A generalized additive model with Poisson distribution was used to assess the association between the number of eczema outpatient visits and short-term exposure to PM_2.5 and PM₁₀. In addition, the association of PM_2.5 and PM₁₀ by age (<65 years, ≥65 years) and gender was evaluated.

Results

A total of 293,343 eczema outpatient visits were recorded. The obtained results indicated that a 10 μg/m³ increase of the same day/lag 1 day/lag 2 days PM_2.5 was associated with increments of 2.33%, 1.81%, and 0.95% in eczema outpatient risk, respectively. On the other hand, a 10 μg/m³ increase of PM₁₀ was associated with eczema outpatients risk increments of 1.97%, 1.65%, and 0.98% respectively. Furthermore, the associations of PM on the increment of eczema were similar in the male and female groups. Results obtained after age stratified analyses indicated that the strongest positive association between PM_2.5 exposure and eczema was observed at lag 0 day with the percent changes being 4.72% and 3.34% in <12 years old, ≥12 and <65 years old, and ≥65 years old groups, respectively.

Conclusion

Short-term exposure to PM_2.5 and PM₁₀ increases the number of eczema outpatients, especially among children and the elderly. The relationship between air quality trends and hospital resource arrangement should be paid attention to by hospital managers which may aid in disease prevention and lower the health burden.

Development of In Vitro Co-Culture Model to Mimic the Cell to Cell Communication in Response to Urban PM2.5

Background

Airborne particulate matter (PM), a widespread air contaminant, is a complex mixture of solids and aerosols composed of particles suspended in the air. PM is associated with inflammatory responses and may worsen inflammatory skin diseases. However, the mechanisms through which PM affects atopic dermatitis (AD) remain unclear.

Objective

To establish an in vitro model that more accurately mimics AD using human keratinocyte (HaCaT), dermal fibroblast (HDF), and mast cell (HMC-1) and using this model to investigate the mechanism through which PMs affect AD.

Methods

An AD-like in vitro model was established by seeding HaCaT, HDF, and HMC-1 cells with recombinant human interleukin (IL)-1α and polyinosinic:polycytidylic acid. We confirmed the effect of PM on the inflammatory cytokine expression of a triple-cell culture model. SRM 1649b Urban Dust, which is mainly composed of polycyclic aromatic hydrocarbons, was used as the reference PM. The effects of PM on the expression levels of proinflammatory cytokines and skin barrier markers were assessed using quantitative real-time polymerase chain reaction and western blotting. Inflammatory cytokine levels were measured using an enzyme-linked immunosorbent assay.

Results

Interactions between various skin cell types were evaluated using a co-culture system. PM treatment increased mRNA and protein levels of the inflammatory cytokines IL-6, IL-1α, tumor necrosis factor-α, IL-4, and IL-1β and decreased the expression of the skin barrier markers filaggrin and loricrin.

Conclusion

Our results suggest that an in vitro triple-cell culture model using HaCaT, HDF, and HMC-1 cells may be reliable for obtaining more physiological, functional, and reproducible data on AD and skin barriers.

Siegesbeckiae Herba Extract and Chlorogenic Acid Ameliorate the Death of HaCaT Keratinocytes Exposed to Airborne Particulate Matter by Mitigating Oxidative Stress

Airborne particulate matter with a size of 10 μm or less (PM₁₀) can cause oxidative damages and inflammatory reactions in the skin. This study was conducted to discover natural products that are potentially useful in protecting the skin from PM₁₀. Among the hot water extracts of a total of 23 medicinal plants, Siegesbeckiae Herba extract (SHE), which showed the strongest protective effect against PM₁₀ cytotoxicity, was selected, and its mechanism of action and active constituents were explored. SHE ameliorated PM₁₀-induced cell death, lactate dehydrogenase (LDH) release, lipid peroxidation, and reactive oxygen species (ROS) production in HaCaT cells. SHE decreased the expression of KEAP1, a negative regulator of NRF2, and increased the expression of NRF2 target genes, such as HMOX1 and NQO1. SHE selectively induced the enzymes involved in the synthesis of GSH (GCL-c and GCL-m), the regeneration of GSH (GSR and G6PDH), and GSH conjugation of xenobiotics (GSTκ1), rather than the enzymes that directly scavenge ROS (SOD1, CAT, and GPX1). SHE increased the cellular content of GSH and mitigated the oxidation of GSH to GSSG caused by PM₁₀ exposure. Of the solvent fractions of SHE, the n-butyl alcohol (BA) fraction ameliorated cell death in both the absence and presence of PM₁₀. The BA fraction contained a high amount of chlorogenic acid. Chlorogenic acid reduced PM₁₀-induced cell death, LDH release, and ROS production. This study suggests that SHE protects cells from PM₁₀ toxicity by increasing the cellular antioxidant capacity and that chlorogenic acid may be an active phytochemical of SHE.

Effects of Exposure to Indoor Fine Particulate Matter on Atopic Dermatitis in Children

This study aimed to investigate the short-term effect of exposure to indoor fine particulate matter (PM_2.5) on atopic dermatitis (AD) symptoms in children. Sixty-four children (40 boys and 24 girls) with moderate-to-severe AD, aged under 18 years were enrolled in the study. They were followed up from February 2019 through November 2020. Exposure to indoor PM_2.5 in each household of the enrolled children and their AD symptoms were measured daily. The generalized linear mixed model was utilized for statistical analysis. Subdivision analysis was performed by stratifying the patients by age, sex, season, severity, the presence of family allergic diseases, sensitization, and indoor environment conditions including temperature and relative humidity. A total of 9,321 person-days of AD symptom data were collected. The average PM_2.5 concentration was 28.7 ± 24.3 µg/m³, with the highest value in winter (47.1 ± 29.6 µg/m³). The overall effect of PM_2.5 on AD symptoms was not statistically significant. However, an increase of 10 µg/m³ in indoor PM_2.5 concentration increased AD symptom scores by 16.5% (95% CI: 6.5, 27.5) in spring and12.6% (95% CI: 4.3, 21.5) in winter, 6.7% (95% CI: 2.3, 11.3) at indoor temperatures of <25.5 °C, and by 15.0% (95% CI: 3.5, 27.7) with no use of an air purifier. The harmful effect of PM_2.5 in boys, in children aged ≥6 years, and in children with inhalant allergen sensitization was significant, showing an increase in AD symptoms of 4.9% (95% CI: 1.4, 8.6), 12.0% (95% CI: 5.3, 19.1), and 7.0% (95% CI: 1.9, 12.3) per 10 µg/m³ of PM_2.5, respectively. Furthermore, children with inhalant allergen sensitization plus severe symptoms (SCORing Atopic Dermatitis, SCORAD ≥ 30.7, median value) showed more harmful effects from exposure to PM_2.5 (15.7% (95% CI: 4.5, 28.1) increase in AD symptom scores per 10 µg/m³ of PM_2.5 increase). Indoor exposure to PM_2.5 exacerbated AD symptoms in children in spring, winter, and at indoor temperatures of < 25.5 °C. In particular, this harmful effect was prominent in children with inhalant allergen sensitization and severe symptoms. Minimizing exposure to indoor PM_2.5 is needed for the proper management of AD.

The Keratinocyte as a Crucial Cell in the Predisposition, Onset, Progression, Therapy and Study of the Atopic Dermatitis

The keratinocyte (KC) is the main functional and structural component of the epidermis, the most external layer of the skin that is highly specialized in defense against external agents, prevention of leakage of body fluids and retention of internal water within the cells. Altered epidermal barrier and aberrant KC differentiation are involved in the pathophysiology of several skin diseases, such as atopic dermatitis (AD). AD is a chronic inflammatory disease characterized by cutaneous and systemic immune dysregulation and skin microbiota dysbiosis. Nevertheless, the pathological mechanisms of this complex disease remain largely unknown. In this review, we summarize current knowledge about the participation of the KC in different aspects of the AD. We provide an overview of the genetic predisposing and environmental factors, inflammatory molecules and signaling pathways of the KC that participate in the physiopathology of the AD. We also analyze the link among the KC, the microbiota and the inflammatory response underlying acute and chronic skin AD lesions.

Genomic Approach to the Assessment of Adverse Effects of Particulate Matters on Skin Cancer and Other Disorders and Underlying Molecular Mechanisms

Air pollutants are in the spotlight because the human body can easily be exposed to them. Among air pollutants, the particulate matter (PM) represents one of the most serious toxicants that can enter the human body through various exposure routes. PMs have various adverse effects and classified as severe carcinogen by International Agency for Research on Cancer. Their physical and chemical characteristics are distinguished by their size. In this review, we summarized the published information on the physicochemical characteristics and adverse effects of PMs on the skin, including carcinogenicity. Through comparisons of biological networks constructed from relationships discussed in the previous scientific publications, we show it is possible to predict skin cancers and other disorders from particle-size-specific signaling alterations of PM-responsive genes. Our review not only helps to grasp the biological association between ambient PMs and skin diseases including cancer, but also provides new approaches to interpret chemical-gene-disease associations regarding the adverse effects of these heterogeneous particles.

Clinical and biological impact of the exposome on the skin

The skin exposome is defined as the totality of environmental exposures over the life course that can induce or modify various skin conditions. Here, we review the impact on the skin of solar exposure, air pollution, hormones, nutrition and psychological factors. Photoageing, photocarcinogenesis and pigmentary changes are well-established consequences of chronic exposure of the skin to solar radiation. Exposure to traffic-related air pollution contributes to skin ageing. Particulate matter and nitrogen dioxide cause skin pigmentation/lentigines, while ozone causes wrinkles and has an impact on atopic eczema. Human skin is a major target of hormones, and they exhibit a wide range of biological activities on the skin. Hormones decline with advancing age influencing skin ageing. Nutrition has an impact on numerous biochemical processes, including oxidation, inflammation and glycation, which may result in clinical effects, including modification of the course of skin ageing and photoageing. Stress and lack of sleep are known to contribute to a pro-inflammatory state, which, in turn, affects the integrity of extracellular matrix proteins, in particular collagen. Hormone dysregulation, malnutrition and stress may contribute to inflammatory skin disorders, such as atopic dermatitis, psoriasis, acne and rosacea.

Effects of Particulate Matter on Healthy Skin: A Comparative Study between High- and Low-Particulate Matter Periods

Background

The influence of airborne particulate matter (PM) on skin has primarily been studied in patients with skin diseases such as atopic dermatitis. Recently, the effect of PM on healthy human skin has gained attention.

Objective

To evaluate the relationship between PM concentration and objective skin changes in healthy subjects.

Methods

This prospective study enrolled 25 healthy volunteers without any skin disease. Data regarding daily meteorological parameters and air pollution were collected during a high-PM period and a low-PM period for 14 days. Environmental and lifestyle factors that might influence skin conditions of subjects were also collected during the study period. Biophysical parameters of the skin such as transepidermal water loss (TEWL), hydration, erythema index, and melanin index were measured. Pores, wrinkles, sebum, and skin tone were evaluated using a facial analysis system.

Results

Mean TEWL value during the high-PM period was significantly higher than that during the low-PM period (10.16 g/m²/h vs. 5.99 g/m²/h; p=0.0005). Mean erythema index was significantly higher in the high-PM period than that in the low-PM period (4.3 vs. 3.42; p=0.038). For facial analysis system indices, uniformity of skin tone was higher in the low-PM period than that in the high-PM period (p<0.0001). In addition, with increasing PM₁₀ and PM_2.5, TEWL also showed increase when other environmental components were constant (regression coefficient [RC]=0.1529, p<0.0001 for PM₁₀; RC=0.2055, p=0.0153 for PM_2.5).

Conclusion

Increased PM concentrations may contribute to disturbed barrier function, increased facial erythema, and uneven skin tone even in healthy human skin.