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Allergies Health Center

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Environmental Illness - Toxic Chemicals in Our Environment

Indoor air pollution

Indoor air pollution can affect you at home, work, or even places you visit. It can increase your risk of a respiratory disease, such as asthma, allergies, and lung cancer. Indoor air pollution can be worse in winter, when windows are shut tight and less fresh air can circulate. A study found that three pollutants commonly found in houses have the greatest effect on health:1

  • Formaldehyde, which is released mainly by building materials.
  • Acrolein, which comes from heating cooking oil to high temperatures and from cigarette smoke.
  • Tiny particles, called respirable particulates, that can get into the lungs. A common source of respirable particulates is tobacco smoke.

See tips for reducing indoor air pollution.

Cigarette smoke

One of the most common and toxic indoor air pollutants is cigarette smoke. Experts believe about 90% of lung cancers are caused by cigarette smoke.2 Smoking, or even inhaling secondhand smoke, increases your risk of heart attack and stroke.

Tobacco smoke contains many chemicals, some of which can cause cancer. If you are a nonsmoker and household members or coworkers will not stop smoking around you, ask that they smoke only in well-ventilated or isolated areas. Never smoke around children or allow them to be exposed to cigarette smoke, especially if they have asthma or allergies.

Exposure to cigarette smoke causes wheezing, coughing, and extra mucus (phlegm) in many children. Secondhand smoke also can cause fluid to build up in the inner ear, which can cause ear infections. Lower respiratory infections, such as pneumonia and bronchitis, are also risks. Sometimes these types of infections become serious enough to require a hospital stay, especially when they develop in babies and young children.3

Babies who are exposed to secondhand smoke are at increased risk for sudden infant death syndrome (SIDS).4

Cigarette smoke may cause asthma in children.4 Also, children with asthma who are exposed to cigarette smoke have more attacks and more severe symptoms than other children with asthma.4

See information on the increased impact of environmental illnesses on children. For example, in recent years, the number of children with asthma has more than doubled, and environmental causes are suspected.

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