**Abstract**

Air pollution with suspended particles and gaseous substances is assumed to be a possible risk factor for bronchial asthma. Bronchial asthma (BA) is one of the most common chronic non-communicable diseases in children and adults, characterized by variable respiratory symptoms and airflow limitation. Asthma is a heterogeneous disease with different underlying disease processes. The most common asthma phenotypes are allergic and non-allergic asthma, differing in the presence of atopy, the type of airway inflammation, responses to inhaled corticosteroid treatment. Meta-analyses, including cohort studies, support the role of fine particles in asthma in children. The question of whether the incidence of asthma in adults is associated with exposure to ambient particulate matter remains open. The chapter describes the effect of fine particles in the ambient air on the formation, course, and underlying mechanisms of different phenotype of bronchial asthma in adults. The role of ambient fine particles in the development of the eosinophilic non-allergic phenotype of bronchial asthma in adults (18–65 years old) has been proven. The hypothesis about different underlying mechanisms in response to exposure to particulate matter for various phenotypes of bronchial asthma was confirmed.

**Keywords:** bronchial asthma, asthma phenotypes, T2-endotype, fine particles, ambient air, epidemiological studies, adults
