According to the WHO, particulate matter affects more people than any other component of air pollution. Inhalation of these types of particles can cause a variety of possible effects ranging from irritation, infection and discomfort to exacerbation of asthma. Smokers or individuals with pre-existing conditions, such as heart or lung disease, may experience additional or more severe symptoms. Long-term exposure has been associated with an increased risk of developing cardiovascular and respiratory disease and even lung cancer. The risks of health effects depend on the level of exposure. At this time, there are no recommendations from health authorities for the general public to wear respiratory protection to help reduce their exposures to particles from air pollution. However, certain individuals are making the choice to wear a respirator.
Q. What best explains the central idea of the passage?