Asthma and air pollution
What is Asthma?
Asthma is a chronic disease that affects the air passages of the lungs. It´s characterized by recurrent attacks of wheezing and loss of breath. These episodes or attacks can happen many times a day, a week or when exposed to certain substances or in specific physical activity.
The World Health Organization estimates that around the world about 300 million people suffer asthma, the majority children. In fact it is consider the most common chronic disease among children. Asthma is not just a public health problem for high income countries: it occurs in all countries regardless of level of development. Over 80% of asthma deaths occurs in low and lower-middle income countries.
During an asthma attack, the lining of the bronchial tubes swell, causing the airways to narrow and reducing the flow of air into and out of the lungs. Recurrent asthma symptoms frequently cause sleeplessness, daytime fatigue, reduced activity levels and school and work absenteeism.
The exact cause of asthma is not completely understood. The strongest risk factors for developing asthma are a combination of genetic predisposition with environmental exposure to inhaled substances and particles that may provoke allergic reactions or irritate the airways. Triggers often bring on asthma attacks. A trigger is anything or condition that causes inflammation in the airways, which then leads to asthma symptoms. Your personal triggers can be very different from those of another person with asthma: * indoor allergens (for example house dust mites in bedding, carpets and stuffed furniture, pollution and pet dander) * outdoor allergens (such as pollens and moulds)
* tobacco smoke
* chemical irritants
* air pollution
Other triggers can include cold air, extreme emotional arousal such as anger or fear, and physical exercise. In some people, asthma can even be triggered by certain medications, such as aspirin and other...
Please join StudyMode to read the full document