Effects of Air Pollutants on Airway Diseases

Abstract

Air pollutants include toxic particles and gases emitted in large quantities from many different combustible materials. They also include particulate matter (PM) and ozone, and biological contaminants, such as viruses and bacteria, which can penetrate the human airway and reach the bloodstream, triggering airway inflammation, dysfunction, and fibrosis. Pollutants that accumulate in the lungs exacerbate symptoms of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Asthma, a heterogeneous disease with complex pathological mechanisms, is characterized by particular symptoms such as shortness of breath, a tight chest, coughing, and wheezing. Patients with COPD often experience exacerbations and worsening of symptoms, which may result in hospitalization and disease progression. PM varies in terms of composition, and can include solid and liquid particles of various sizes. PM concentrations are higher in urban areas. Ozone is one of the most toxic photochemical air pollutants. In general, air pollution decreases quality of life and life expectancy. It exacerbates acute and chronic respiratory symptoms in patients with chronic airway diseases, and increases the morbidity and risk of hospitalization associated with respiratory diseases. However, the mechanisms underlying these effects remain unclear. Therefore, we reviewed the impact of air pollutants on airway diseases such as asthma and COPD, focusing on their underlying mechanisms.

Long-Term PM2.5 Exposure Is Associated with Symptoms of Acute Respiratory Infections among Children under Five Years of Age in Kenya, 2014

“…PM is the principal component of many indoor and outdoor pollution mixtures [ 10 ]. Exposure to PM with an aerodynamic diameter <2.5 microns (PM ), also known as fine PM, has major implications for health [ 11 ].…”

“…The most visible symptoms of PM exposure are the result of the activation of the inflammasome and subsequent acute and chronic responses (e.g., asthma) [ 12 ]. Persistent exposure to PM results in a chronic inflammatory response, worsening lung tissue injury, exacerbation of respiratory disease, and can potentially result in alveolar collapse [ 10 ].…”

Current Insights on the Impact of Proteomics in Respiratory Allergies

“…The World Health Organization (WHO) estimates that around 25% of the world’s population suffers from respiratory allergic diseases [ 1 ]. Airborne allergens cause inflammation of the airways, and the most common allergens are house dust mites, pollen, proteins in animal hair, and animal urine.…”

“…Air pollutants can aggravate allergy symptoms. The most important are particulate matter (PM 10 and PM 2.5 ), ozone (O 3 ), nitrogen dioxide (NO 2 ), carbon monoxide (CO), and sulfur dioxide (SO 2 ), among others [ 1 ]. Pollutants penetrate the airways, triggering airway inflammation and exacerbating respiratory symptoms.…”

Air pollution induces Staphylococcus aureus USA300 respiratory tract colonisation mediated by specific bacterial genetic responses dependent on the global virulence gene regulators Agr and Sae

“…In seeking to explain how PM adversely affects chronic and infectious diseases, research has focused on direct damage to host tissue caused by PM exposure, including increased inflammation, and oxidative stress (Lee et al, 2021). It is also known that in infection, PM can potentiate disease by repressing the immune system (Castranova et al, 2001; Liu, J. et al, 2019; Migliaccio et al, 2013; Shears et al, 2020; Yang et al, 2001) and by disruption of epithelial function (Liu et al, 2019; Misiukiewicz-Stepien & Paplinska-Goryca, 2021).…”