Secondhand Smoke Facts

Secondhand smoke is a mixture of two forms of smoke that come from burning tobacco: side-stream smoke (the smoke from the lighted end of a cigarette) and mainstream smoke (the smoke exhaled by a smoker). Side-stream smoke is more toxic than mainstream smoke, as it has much higher concentrations of cancer-causing substances.

The dangers of secondhand smoke are immense. It is classified as a Class A carcinogen, as it has been proven to cause cancer in people. Secondhand smoke contains more than 7,000 chemicals — 250 are known to be harmful, and at least 70 cause cancer.

Approximately 2.5M nonsmokers have died since 1964 due to health issues caused by exposure to SHS.
In nonsmokers, SHS causes around 7.3K lung cancer deaths/year & nearly 34K heart disease deaths/year.

There is no safe level of exposure to secondhand smoke. Not even air-cleaning systems, ventilation systems or separate smoking sections can eliminate its risk. It causes disease and death in people who don’t smoke, including coronary heart disease, stroke and lung cancer. In fact, secondhand smoke kills nearly 50,000 nonsmokers each year.

People who die in the U.S. each year from cigarette smoking and exposure to secondhand smoke: approximately 480,000.

Secondhand Smoke and Children

Secondhand smoke is dangerous to you, but it’s especially harmful to your children. Infants and young children are particularly vulnerable, as their bodies and lungs have not yet fully developed. Exposure to secondhand smoke can lead to:

  • Sudden infant death syndrome (SIDS)
  • Ear infections
  • Asthma attacks
  • Bronchitis
  • Pneumonia
  • Low birth weight, decreased blood flow and a weaker heart, lungs, digestive system and nervous system when exposed during pregnancy
30 minutes of exposure to secondhand smoke can cause heart damage similar to that of an everyday smoker.