Asthma and the Environment

Asthma and the Environment

Asthma attacks have been linked to exposure to environmental factors such as allergens, tobacco smoke, and indoor and outdoor air pollution. Asthma attacks can be reduced by avoiding exposure to known triggers. Asthma symptoms can be managed by following directions on prescribed medications.

A number of studies have reported associations between air pollution exposures and asthma. For example, researchers have found an association between increased hospital admissions for asthma and some air pollution particles.

Air pollution, such as ozone and particle pollution, can make asthma symptoms worse and trigger attacks. Adults and children with asthma are more likely to have symptoms when ozone and particle pollution are in the air. Ozone is often found in smog and particle pollution is often found in haze, smoke, and dust.

Ozone is often worse on hot summer days, especially in the afternoons and early evenings.

Particle pollution can be bad any time of year, even in winter. It can be especially bad:

  • when the weather is calm, and air pollution can build up,
  • near busy roads, during rush hour, and around factories that produce air pollution and,
  • when smoke is in the air from wood stoves, fireplaces, or burning vegetation.

Important asthma triggers are:

  • environmental tobacco smoke, also known as secondhand smoke;
  • dust mites;
  • outdoor air pollution;
  • Smoke from burning wood and grass;
  • cockroach allergen;
  • pets;
  • mold;
  • strenuous physical exercise;
  • some medicines;
  • weather conditions, such as thunderstorms, high humidity, or cold air;
  • some foods and food additives; and
  • strong emotional states that can lead to hyperventilation and an asthma attack.